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TDMS Study 05156-05 Pathology Tables

NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09




       Facility:  Battelle Northwest

       Chemical CAS #:  10026-24-1

       Lock Date:  07/15/94

       Cage Range:  All

       Reasons For Removal:    All

       Removal Date Range:     All

       Treatment Groups:       Include All




































Note:  Animals arranged according to CID number

                                                              Page   1


NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 6| 7| 7| 7| 7| 5| 7| 7| 6| 7| 7| 7| 6| 7| 5| 7| 6| 7| 7| 7| 7| 7| 7| 7|             
                             DAY ON TEST   | 0| 7| 3| 0| 3| 3| 7| 3| 3| 6| 3| 3| 3| 1| 3| 8| 3| 0| 3| 3| 2| 2| 3| 3| 3|             
                                           | 5| 9| 5| 9| 6| 6| 2| 5| 7| 6| 7| 6| 6| 0| 5| 2| 7| 2| 6| 7| 7| 1| 3| 7| 5|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   FISCHER 344 RATS FEMALE                 | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1|             
    CONTROL                                | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
                                           | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 ALIMENTARY SYSTEM                         |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Esophagus                               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Colon                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  A  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Cecum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  A  +  +|             
      Leukemia Mononuclear                 |                      X                                                   |             
                                            __________________________________________________________________________|             
   Intestine Small, Duodenum               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Jejunum                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  A  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Ileum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
                                            __________________________________________________________________________|             
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 | X  X     X           X     X                                             |             
                                            __________________________________________________________________________|             
   Mesentery                               |       +     +  +                             +                           |             
                                            __________________________________________________________________________|             
   Oral Mucosa                             |                +                                                         |             
      Pharyngeal, Squamous Cell Papilloma  |                X                                                         |             
                                            __________________________________________________________________________|             
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
      Leukemia Mononuclear                 |                            X                                             |             
                                            __________________________________________________________________________|             
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
 _____________________________________________________________________________________________________________________|             
 CARDIOVASCULAR SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Carcinoma, Metastatic, Thyroid Gland |                                                                          |             
      Leukemia Mononuclear                 |    X                                                                     |             
      Schwannoma Benign                    |                                                             X            |             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM                          |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Carcinoma, Metastatic, Kidney        |                               X                                          |             
      Leukemia Mononuclear                 | X  X     X           X     X                                             |             
                                            __________________________________________________________________________|             
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 | X  X     X           X     X                                             |             
      Pheochromocytoma Benign              |          X                 X                                             |             
                                            __________________________________________________________________________|             
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
      Adenoma                              |                                                          X           X   |             
      Carcinoma                            |                   X                                                      |             
                                            __________________________________________________________________________|             
   Parathyroid Gland                       | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Pituitary Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 | X  X     X                 X                                             |             
      Pars Distalis, Adenoma               | X     X  X  X  X  X  X  X        X  X  X     X  X  X  X     X  X  X  X  X|             
                                            __________________________________________________________________________|             
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
      C-Cell, Adenoma                      |       X        X                                      X  X               |             
      C-Cell, Carcinoma                    |                                                                X         |             
 _____________________________________________________________________________________________________________________|             
 GENERAL BODY SYSTEM                       |                                                                          |             
                                           |                                                                          |             
 _____________________________________________________________________________________________________________________|             

                                                             Page   2                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 6| 7| 7| 7| 7| 5| 7| 7| 6| 7| 7| 7| 6| 7| 5| 7| 6| 7| 7| 7| 7| 7| 7| 7|             
                             DAY ON TEST   | 0| 7| 3| 0| 3| 3| 7| 3| 3| 6| 3| 3| 3| 1| 3| 8| 3| 0| 3| 3| 2| 2| 3| 3| 3|             
                                           | 5| 9| 5| 9| 6| 6| 2| 5| 7| 6| 7| 6| 6| 0| 5| 2| 7| 2| 6| 7| 7| 1| 3| 7| 5|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   FISCHER 344 RATS FEMALE                 | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1|             
    CONTROL                                | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
                                           | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 GENERAL BODY SYSTEM - cont                |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Peritoneum                              |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 GENITAL SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Clitoral Gland                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Adenoma                              |       X                                                     X     X      |             
      Carcinoma                            |             X  X                                                         |             
                                            __________________________________________________________________________|             
   Ovary                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Granulosa Cell Tumor Benign          |                                                                          |             
      Leukemia Mononuclear                 |                      X                                                   |             
                                            __________________________________________________________________________|             
   Uterus                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Polyp Stromal                        |                X     X                          X           X        X   |             
      Sarcoma Stromal                      |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 | X        X                 X                                             |             
                                            __________________________________________________________________________|             
   Lymph Node                              | +                          +                                             |             
      Pancreatic, Leukemia Mononuclear     | X                          X                                             |             
      Renal, Leukemia Mononuclear          |                            X                                             |             
                                            __________________________________________________________________________|             
   Lymph Node, Bronchial                   | +  M  M  +  +  +  +  +  +  +  +  M  M  M  M  M  +  +  +  +  +  +  M  +  M|             
      Leukemia Mononuclear                 | X        X           X     X                                             |             
                                            __________________________________________________________________________|             
   Lymph Node, Mandibular                  | +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  M  +  +  +  +|             
      Leukemia Mononuclear                 | X  X     X           X     X                                             |             
                                            __________________________________________________________________________|             
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
      Leukemia Mononuclear                 | X  X     X           X     X                                             |             
                                            __________________________________________________________________________|             
   Lymph Node, Mediastinal                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  M  +  M  M|             
      Leukemia Mononuclear                 | X        X           X     X                                             |             
                                            __________________________________________________________________________|             
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
      Leukemia Mononuclear                 | X  X     X           X     X     X                                       |             
                                            __________________________________________________________________________|             
   Thymus                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  M  M  +  M|             
      Leukemia Mononuclear                 |          X                                                               |             
 _____________________________________________________________________________________________________________________|             
 INTEGUMENTARY SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Mammary Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Adenoma                              |                   X                                         X            |             
      Carcinoma                            |                                                       X                  |             
      Carcinoma, Multiple                  |                                                                          |             
      Fibroadenoma                         | X  X     X                 X           X     X           X        X  X   |             
      Fibroadenoma, Multiple               |       X                 X           X                       X            |             
                                            __________________________________________________________________________|             
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Squamous Cell Papilloma              |                                                          X               |             
      Subcutaneous Tissue, Lipoma          |                                  X                                       |             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM                    |                                                                          |             
                                           |                                                                          |             
 _____________________________________________________________________________________________________________________|             

                                                             Page   3                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 6| 7| 7| 7| 7| 5| 7| 7| 6| 7| 7| 7| 6| 7| 5| 7| 6| 7| 7| 7| 7| 7| 7| 7|             
                             DAY ON TEST   | 0| 7| 3| 0| 3| 3| 7| 3| 3| 6| 3| 3| 3| 1| 3| 8| 3| 0| 3| 3| 2| 2| 3| 3| 3|             
                                           | 5| 9| 5| 9| 6| 6| 2| 5| 7| 6| 7| 6| 6| 0| 5| 2| 7| 2| 6| 7| 7| 1| 3| 7| 5|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   FISCHER 344 RATS FEMALE                 | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1|             
    CONTROL                                | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
                                           | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM - cont             |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 NERVOUS SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 RESPIRATORY SYSTEM                        |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Carcinoma, Metastatic, Mammary Gland |                                                                          |             
      Leukemia Mononuclear                 | X  X     X           X     X                                             |             
                                            __________________________________________________________________________|             
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |          X                                                               |             
                                            __________________________________________________________________________|             
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 SPECIAL SENSES SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Eye                                     |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 | X  X     X                 X                                             |             
      Lipoma                               |                                                                          |             
      Bilateral, Renal Tubule, Carcinoma,  |                                                                          |             
           Multiple                        |                               X                                          |             
                                            __________________________________________________________________________|             
   Urinary Bladder                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
 _____________________________________________________________________________________________________________________|             
 SYSTEMIC LESIONS                          |                                                                          |             
                                            __________________________________________________________________________|             
   Multiple Organs                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 | X  X     X           X     X     X                                       |             
 _____________________________________________________________________________________________________________________|             

                                                             Page   4                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 6| 7| 7| 7| 7| 6| 7| 7| 7| 7| 6| 7| 6| 7| 7| 7| 5| 7| 7| 7| 7| 7| 3| 7| 5|            |
                             DAY ON TEST   | 3| 3| 1| 3| 3| 9| 3| 3| 3| 3| 3| 3| 9| 3| 3| 2| 8| 0| 3| 3| 3| 3| 8| 3| 6|            |
                                           | 2| 5| 9| 6| 6| 2| 6| 7| 5| 6| 8| 6| 4| 6| 5| 7| 2| 9| 3| 5| 6| 7| 5| 5| 9|            |
 _____________________________________________________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     O      |
   FISCHER 344 RATS FEMALE                 | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     T      |
                               ANIMAL ID   | 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1|     A      |
    CONTROL                                | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|     L      |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 ALIMENTARY SYSTEM                         |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Esophagus                               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Colon                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Cecum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
      Leukemia Mononuclear                 |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Intestine Small, Duodenum               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Jejunum                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +|  47        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Ileum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 | X     X     X        X              X        X        X        X  X      |         14 |
                                            __________________________________________________________________________|____________|
   Mesentery                               |                                                          +               |   5        |
                                            __________________________________________________________________________|____________|
   Oral Mucosa                             |                                                                          |   1        |
      Pharyngeal, Squamous Cell Papilloma  |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Leukemia Mononuclear                 |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
 _____________________________________________________________________________________________________________________|            |
 CARDIOVASCULAR SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Carcinoma, Metastatic, Thyroid Gland |          X                                                               |          1 |
      Leukemia Mononuclear                 |                                     X                                    |          2 |
      Schwannoma Benign                    |                                                                          |          1 |
 _____________________________________________________________________________________________________________________|            |
 ENDOCRINE SYSTEM                          |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +|  49        |
      Carcinoma, Metastatic, Kidney        |                                                                          |          1 |
      Leukemia Mononuclear                 | X     X                             X                 X                  |          9 |
                                            __________________________________________________________________________|____________|
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +|  48        |
      Leukemia Mononuclear                 | X     X                             X                 X                  |          9 |
      Pheochromocytoma Benign              |                                                                          |          2 |
                                            __________________________________________________________________________|____________|
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Adenoma                              |                         X                                      X         |          4 |
      Carcinoma                            |          X                                                               |          2 |
                                            __________________________________________________________________________|____________|
   Parathyroid Gland                       | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Pituitary Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |       X                             X                                    |          6 |
      Pars Distalis, Adenoma               | X  X  X  X  X  X  X  X  X  X  X        X  X  X  X  X  X  X           X  X|         40 |
 __________________________________________________________________________________________________________________________________ 

                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  

                                                             Page   5                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 6| 7| 7| 7| 7| 6| 7| 7| 7| 7| 6| 7| 6| 7| 7| 7| 5| 7| 7| 7| 7| 7| 3| 7| 5|            |
                             DAY ON TEST   | 3| 3| 1| 3| 3| 9| 3| 3| 3| 3| 3| 3| 9| 3| 3| 2| 8| 0| 3| 3| 3| 3| 8| 3| 6|            |
                                           | 2| 5| 9| 6| 6| 2| 6| 7| 5| 6| 8| 6| 4| 6| 5| 7| 2| 9| 3| 5| 6| 7| 5| 5| 9|            |
 _____________________________________________________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     O      |
   FISCHER 344 RATS FEMALE                 | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     T      |
                               ANIMAL ID   | 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1|     A      |
    CONTROL                                | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|     L      |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 ENDOCRINE SYSTEM - cont                   |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      C-Cell, Adenoma                      |                   X                                                  X   |          6 |
      C-Cell, Carcinoma                    |          X              X                                                |          3 |
 _____________________________________________________________________________________________________________________|            |
 GENERAL BODY SYSTEM                       |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Peritoneum                              |                                              +                           |   1        |
 _____________________________________________________________________________________________________________________|            |
 GENITAL SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Clitoral Gland                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Adenoma                              |                         X                             X                  |          5 |
      Carcinoma                            |                                                                          |          2 |
                                            __________________________________________________________________________|____________|
   Ovary                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Granulosa Cell Tumor Benign          |          X                                                               |          1 |
      Leukemia Mononuclear                 | X     X                             X                                    |          4 |
                                            __________________________________________________________________________|____________|
   Uterus                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Polyp Stromal                        | X                 X                                                     X|          8 |
      Sarcoma Stromal                      |                                              X                           |          1 |
 _____________________________________________________________________________________________________________________|            |
 HEMATOPOIETIC SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +|  49        |
      Leukemia Mononuclear                 |       X                             X                 X           X      |          7 |
                                            __________________________________________________________________________|____________|
   Lymph Node                              |                                                                          |   2        |
      Pancreatic, Leukemia Mononuclear     |                                                                          |          2 |
      Renal, Leukemia Mononuclear          |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Bronchial                   | M  +  M  +  +  +  +  +  M  +  +  +  M  M  +  +  +  M  M  M  +  +  M  M  M|  30        |
      Leukemia Mononuclear                 |                                              X                 X         |          6 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mandibular                  | +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  M  M  +  +  +  +  M  +  +|  44        |
      Leukemia Mononuclear                 | X                                   X        X        X        X         |         10 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Leukemia Mononuclear                 |       X                             X        X        X           X      |         10 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mediastinal                 | +  M  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +|  43        |
      Leukemia Mononuclear                 | X     X                             X        X        X           X      |         10 |
                                            __________________________________________________________________________|____________|
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Leukemia Mononuclear                 | X     X     X        X              X        X        X        X  X      |         15 |
                                            __________________________________________________________________________|____________|
   Thymus                                  | +  M  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  M  +  +  M  +  +  +|  42        |
      Leukemia Mononuclear                 |                                                                          |          1 |
 _____________________________________________________________________________________________________________________|            |
 INTEGUMENTARY SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Mammary Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 __________________________________________________________________________________________________________________________________ 

                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  

                                                             Page   6                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 6| 7| 7| 7| 7| 6| 7| 7| 7| 7| 6| 7| 6| 7| 7| 7| 5| 7| 7| 7| 7| 7| 3| 7| 5|            |
                             DAY ON TEST   | 3| 3| 1| 3| 3| 9| 3| 3| 3| 3| 3| 3| 9| 3| 3| 2| 8| 0| 3| 3| 3| 3| 8| 3| 6|            |
                                           | 2| 5| 9| 6| 6| 2| 6| 7| 5| 6| 8| 6| 4| 6| 5| 7| 2| 9| 3| 5| 6| 7| 5| 5| 9|            |
 _____________________________________________________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     O      |
   FISCHER 344 RATS FEMALE                 | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     T      |
                               ANIMAL ID   | 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1|     A      |
    CONTROL                                | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|     L      |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 INTEGUMENTARY SYSTEM - cont               |                                                                          |            |
                                           |                                                                          |            |
      Adenoma                              |                                                                          |          2 |
      Carcinoma                            |                                                    X                     |          2 |
      Carcinoma, Multiple                  |                               X                                          |          1 |
      Fibroadenoma                         |    X           X           X     X     X           X           X     X  X|         18 |
      Fibroadenoma, Multiple               |                                                                          |          4 |
                                            __________________________________________________________________________|____________|
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Squamous Cell Papilloma              |                                                                          |          1 |
      Subcutaneous Tissue, Lipoma          |                                                    X                     |          2 |
 _____________________________________________________________________________________________________________________|            |
 MUSCULOSKELETAL SYSTEM                    |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 NERVOUS SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 RESPIRATORY SYSTEM                        |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Carcinoma, Metastatic, Mammary Gland |                               X                                          |          1 |
      Leukemia Mononuclear                 | X     X                             X        X        X        X  X      |         12 |
                                            __________________________________________________________________________|____________|
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |                                     X                                    |          2 |
                                            __________________________________________________________________________|____________|
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 SPECIAL SENSES SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Eye                                     |          +                                                               |   1        |
 _____________________________________________________________________________________________________________________|            |
 URINARY SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +|  49        |
      Leukemia Mononuclear                 |       X                             X                 X                  |          7 |
      Lipoma                               |                                           X                              |          1 |
      Bilateral, Renal Tubule, Carcinoma,  |                                                                          |            |
           Multiple                        |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Urinary Bladder                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
 __________________________________________________________________________________________________________________________________ 
 SYSTEMIC LESIONS                          |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Multiple Organs                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 | X     X     X        X              X        X        X        X  X      |         15 |
 __________________________________________________________________________________________________________________________________ 

                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  

                                                             Page   7                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 7| 6| 6| 7| 6| 6| 7| 7| 4| 5| 6| 6| 0| 6| 7| 7| 5| 7| 7| 7| 5| 7| 7| 7|             
                             DAY ON TEST   | 3| 3| 1| 5| 3| 7| 1| 0| 3| 8| 8| 1| 9| 8| 7| 3| 3| 2| 1| 3| 3| 1| 0| 3| 3|             
                                           | 1| 5| 0| 2| 7| 3| 0| 2| 6| 3| 5| 0| 4| 3| 0| 6| 7| 6| 4| 6| 7| 7| 9| 5| 5|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   FISCHER 344 RATS FEMALE                 | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3|             
    0.3                                    | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
    MG/M3                                  | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 ALIMENTARY SYSTEM                         |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Esophagus                               | +  +  +  +  +  +  +  +  +  +  +  +  +     +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Colon                  | A  +  +  +  +  +  +  +  +  +  +  +  +     +  +  +  +  A  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  +  +  +     +  +  +  +  A  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Cecum                  | A  +  +  +  +  +  +  +  +  +  +  +  +     +  +  +  +  A  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                                  X                                       |             
                                            __________________________________________________________________________|             
   Intestine Small, Duodenum               | A  +  +  +  +  +  +  +  +  +  +  +  +     +  +  +  +  A  +  +  +  +  +  I|             
      Leukemia Mononuclear                 |                                  X                                       |             
                                            __________________________________________________________________________|             
   Intestine Small, Jejunum                | A  +  +  +  +  +  +  +  +  +  +  +  +     +  +  +  +  A  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Ileum                  | A  +  +  +  +  +  +  +  +  +  +  +  +     +  +  +  +  A  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +     +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                X  X  X     X  X  X  X                    X              X|             
                                            __________________________________________________________________________|             
   Mesentery                               |                +                                      +  +           +   |             
      Sarcoma Stromal, Metastatic, Uterus  |                                                                          |             
                                            __________________________________________________________________________|             
   Oral Mucosa                             |                                                                          |             
      Pharyngeal, Squamous Cell Papilloma  |                                                                          |             
                                            __________________________________________________________________________|             
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +     +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                                                                         X|             
                                            __________________________________________________________________________|             
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +     +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +     +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +     +  +  +  +  +  +  +  +  +  +  +|             
      Carcinoid Tumor Benign               |                                           X                              |             
                                            __________________________________________________________________________|             
   Tooth                                   |          +                                                               |             
 _____________________________________________________________________________________________________________________|             
 CARDIOVASCULAR SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +     +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                X                 X                                      X|             
      Schwannoma Benign                    |                                                                X         |             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM                          |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +     +  +  +  +  +  +  +  +  +  +  +|             
      Adenoma                              |                                                       X                  |             
      Leukemia Mononuclear                 |                X     X     X     X                                       |             
                                            __________________________________________________________________________|             
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +     +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                X     X     X     X                                       |             
      Pheochromocytoma Benign              |                      X                                                   |             
                                            __________________________________________________________________________|             
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +     +  +  +  +  +  +  +  +  +  +  +|             
      Adenoma                              |                                                          X               |             
                                            __________________________________________________________________________|             
   Parathyroid Gland                       | +  +  +  +  +  +  +  +  +  +  +  +  +     +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Pituitary Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +     +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                X           X     X                                      X|             
      Pars Distalis, Adenoma               | X  X     X  X  X  X  X  X     X           X  X  X  X  X  X  X  X  X  X  X|             
                                            __________________________________________________________________________|             
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +     +  +  +  +  +  +  +  +  +  +  +|             
      C-Cell, Adenoma                      | X                                                              X         |             
      Follicular Cell, Adenoma             |                                                                          |             
 _____________________________________________________________________________________________________________________|             

                                                             Page   8                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 7| 6| 6| 7| 6| 6| 7| 7| 4| 5| 6| 6| 0| 6| 7| 7| 5| 7| 7| 7| 5| 7| 7| 7|             
                             DAY ON TEST   | 3| 3| 1| 5| 3| 7| 1| 0| 3| 8| 8| 1| 9| 8| 7| 3| 3| 2| 1| 3| 3| 1| 0| 3| 3|             
                                           | 1| 5| 0| 2| 7| 3| 0| 2| 6| 3| 5| 0| 4| 3| 0| 6| 7| 6| 4| 6| 7| 7| 9| 5| 5|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   FISCHER 344 RATS FEMALE                 | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3|             
    0.3                                    | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
    MG/M3                                  | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 GENERAL BODY SYSTEM                       |                                                                          |             
                                           |                                                                          |             
    None                                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 GENITAL SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Clitoral Gland                          | +  M  +  +  +  +  +  +  +  +  +  +  +     +  +  +  +  +  +  +  +  +  +  +|             
      Adenoma                              |          X     X                                                         |             
      Carcinoma                            |       X                             X                                    |             
                                            __________________________________________________________________________|             
   Ovary                                   | +  +  +  +  +  +  +  +  +  +  +  +  +     +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                X     X           X                                       |             
      Bilateral, Granulosa-Theca Tumor     |                                                                          |             
          Benign                           |                                                                          |             
                                            __________________________________________________________________________|             
   Uterus                                  | +  +  +  +  +  +  +  +  +  +  +  +  +     +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                      X           X                                      X|             
      Polyp Stromal                        |                            X     X        X  X                       X   |             
      Sarcoma Stromal                      |                   X                                                      |             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +     +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                X           X     X                                      X|             
                                            __________________________________________________________________________|             
   Lymph Node                              |                            +     +                                       |             
      Pancreatic, Leukemia Mononuclear     |                            X     X                                       |             
      Renal, Leukemia Mononuclear          |                                  X                                       |             
                                            __________________________________________________________________________|             
   Lymph Node, Bronchial                   | M  M  +  +  +  M  +  +  +  +  +  +  +     M  +  +  M  M  +  +  M  M  M  +|             
      Leukemia Mononuclear                 |                      X     X  X  X                       X              X|             
                                            __________________________________________________________________________|             
   Lymph Node, Mandibular                  | +  M  M  +  +  +  M  +  +  +  +  +  +     M  +  +  +  +  +  +  M  +  +  +|             
      Leukemia Mononuclear                 |                X     X     X     X                       X              X|             
                                            __________________________________________________________________________|             
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  +  +  +  +  +     +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                X     X     X     X                       X              X|             
                                            __________________________________________________________________________|             
   Lymph Node, Mediastinal                 | +  +  +  M  +  +  +  +  M  +  +  +  +     +  +  +  +  +  +  +  +  +  M  +|             
      Leukemia Mononuclear                 |                X     X     X     X                                      X|             
                                            __________________________________________________________________________|             
   Spleen                                  | A  +  +  +  +  +  +  +  +  +  +  +  +     +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                X  X  X     X  X  X  X                    X              X|             
                                            __________________________________________________________________________|             
   Thymus                                  | +  +  +  +  M  +  +  +  +  +  +  +  +     +  M  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                            X     X                                      X|             
 _____________________________________________________________________________________________________________________|             
 INTEGUMENTARY SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Mammary Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +     +  +  +  +  +  +  +  +  +  +  +|             
      Carcinoma                            |                                                                   X      |             
      Fibroadenoma                         | X  X     X     X  X              X              X        X  X           X|             
      Fibroadenoma, Multiple               |       X                                                           X      |             
                                            __________________________________________________________________________|             
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +     +  +  +  +  +  +  +  +  +  +  +|             
      Sebaceous Gland, Adenoma             |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM                    |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +     +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             

                                                             Page   9                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 7| 6| 6| 7| 6| 6| 7| 7| 4| 5| 6| 6| 0| 6| 7| 7| 5| 7| 7| 7| 5| 7| 7| 7|             
                             DAY ON TEST   | 3| 3| 1| 5| 3| 7| 1| 0| 3| 8| 8| 1| 9| 8| 7| 3| 3| 2| 1| 3| 3| 1| 0| 3| 3|             
                                           | 1| 5| 0| 2| 7| 3| 0| 2| 6| 3| 5| 0| 4| 3| 0| 6| 7| 6| 4| 6| 7| 7| 9| 5| 5|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   FISCHER 344 RATS FEMALE                 | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3|             
    0.3                                    | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
    MG/M3                                  | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM - cont             |                                                                          |             
                                           |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 NERVOUS SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +     +  +  +  +  +  +  +  +  +  +  +|             
      Astrocytoma Malignant                |    X                                                                     |             
      Leukemia Mononuclear                 |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 RESPIRATORY SYSTEM                        |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +     +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +     +  +  +  +  +  +  +  +  +  +  +|             
      Alveolar/Bronchiolar Adenoma         |                                                       X                  |             
      Alveolar/Bronchiolar Carcinoma       |                                                                          |             
      Leukemia Mononuclear                 |                X  X  X     X  X  X                       X              X|             
      Mesothelioma Malignant, Metastatic,  |                                                                          |             
           Pleura                          |       X                                                                  |             
      Sarcoma, Metastatic, Uncertain       |                                                                          |             
          Primary Site                     |                                                          X               |             
                                            __________________________________________________________________________|             
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +     +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                            X     X                                       |             
                                            __________________________________________________________________________|             
   Pleura                                  |       +                                                                  |             
      Mesothelioma Malignant               |       X                                                                  |             
                                            __________________________________________________________________________|             
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +     +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 SPECIAL SENSES SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Eye                                     |       +                                                                  |             
                                            __________________________________________________________________________|             
   Zymbal's Gland                          |                                  +                                       |             
      Carcinoma                            |                                  X                                       |             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +     +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                X     X     X     X                                      X|             
      Mesenchymal Tumor Benign             |                                                                          |             
                                            __________________________________________________________________________|             
   Urinary Bladder                         | +  +  +  +  +  +  +  +  +  +  +  +  +     +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                                                                         X|             
 _____________________________________________________________________________________________________________________|             
 SYSTEMIC LESIONS                          |                                                                          |             
                                            __________________________________________________________________________|             
   Multiple Organs                         | +  +  +  +  +  +  +  +  +  +  +  +  +     +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                X  X  X     X  X  X  X                    X              X|             
      Mesothelioma Malignant               |       X                                                                  |             
 _____________________________________________________________________________________________________________________|             

                                                             Page  10                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 4| 7| 7| 7| 6| 7| 7| 7| 7| 3| 7| 7| 7| 5| 7| 7| 7| 7| 7| 7| 7| 6| 7| 4|            |
                             DAY ON TEST   | 3| 2| 3| 3| 3| 8| 3| 3| 2| 0| 6| 3| 3| 3| 2| 3| 2| 3| 3| 3| 3| 3| 7| 3| 9|            |
                                           | 5| 0| 6| 7| 5| 7| 6| 6| 2| 9| 2| 5| 5| 6| 6| 5| 8| 7| 5| 6| 6| 6| 3| 5| 1|            |
 _____________________________________________________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     O      |
   FISCHER 344 RATS FEMALE                 | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     T      |
                               ANIMAL ID   | 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3|     A      |
    0.3                                    | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|     L      |
    MG/M3                                  | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 ALIMENTARY SYSTEM                         |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Esophagus                               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Colon                  | +  A  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  45        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  47        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Cecum                  | +  A  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  45        |
      Leukemia Mononuclear                 |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Intestine Small, Duodenum               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  46        |
      Leukemia Mononuclear                 |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Intestine Small, Jejunum                | +  A  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  45        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Ileum                  | +  A  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  45        |
                                            __________________________________________________________________________|____________|
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Leukemia Mononuclear                 |                         X  X           X           X           X  X     X|         16 |
                                            __________________________________________________________________________|____________|
   Mesentery                               | +                       +  +  +                                          |   8        |
      Sarcoma Stromal, Metastatic, Uterus  |                               X                                          |          1 |
                                            __________________________________________________________________________|____________|
   Oral Mucosa                             |             +        +                                                   |   2        |
      Pharyngeal, Squamous Cell Papilloma  |             X        X                                                   |          2 |
                                            __________________________________________________________________________|____________|
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Leukemia Mononuclear                 |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Carcinoid Tumor Benign               |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Tooth                                   |                                                                      +   |   2        |
 _____________________________________________________________________________________________________________________|            |
 CARDIOVASCULAR SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Leukemia Mononuclear                 |                         X  X                                             |          5 |
      Schwannoma Benign                    |                                                             X            |          2 |
 _____________________________________________________________________________________________________________________|            |
 ENDOCRINE SYSTEM                          |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Adenoma                              |                                                                          |          1 |
      Leukemia Mononuclear                 |                         X  X           X                       X  X     X|         10 |
                                            __________________________________________________________________________|____________|
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Leukemia Mononuclear                 |                         X  X           X                       X  X     X|         10 |
      Pheochromocytoma Benign              |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Adenoma                              |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Parathyroid Gland                       | +  +  +  +  +  +  +  +  +  +  M  M  +  +  +  +  +  +  +  +  +  +  +  +  +|  47        |
                                            __________________________________________________________________________|____________|
   Pituitary Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
 __________________________________________________________________________________________________________________________________ 

                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  

                                                             Page  11                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 4| 7| 7| 7| 6| 7| 7| 7| 7| 3| 7| 7| 7| 5| 7| 7| 7| 7| 7| 7| 7| 6| 7| 4|            |
                             DAY ON TEST   | 3| 2| 3| 3| 3| 8| 3| 3| 2| 0| 6| 3| 3| 3| 2| 3| 2| 3| 3| 3| 3| 3| 7| 3| 9|            |
                                           | 5| 0| 6| 7| 5| 7| 6| 6| 2| 9| 2| 5| 5| 6| 6| 5| 8| 7| 5| 6| 6| 6| 3| 5| 1|            |
 _____________________________________________________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     O      |
   FISCHER 344 RATS FEMALE                 | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     T      |
                               ANIMAL ID   | 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3|     A      |
    0.3                                    | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|     L      |
    MG/M3                                  | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 ENDOCRINE SYSTEM - cont                   |                                                                          |            |
                                           |                                                                          |            |
      Leukemia Mononuclear                 |                         X                                               X|          6 |
      Pars Distalis, Adenoma               | X  X  X  X  X  X  X  X  X        X  X  X        X  X  X  X  X  X  X      |         39 |
                                            __________________________________________________________________________|____________|
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      C-Cell, Adenoma                      |       X  X                       X        X                              |          6 |
      Follicular Cell, Adenoma             |                                           X                              |          1 |
 _____________________________________________________________________________________________________________________|            |
 GENERAL BODY SYSTEM                       |                                                                          |            |
                                           |                                                                          |            |
    None                                   |                                                                          |            |
 _____________________________________________________________________________________________________________________|            |
 GENITAL SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Clitoral Gland                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
      Adenoma                              |       X     X        X              X                             X      |          7 |
      Carcinoma                            |          X                                                               |          3 |
                                            __________________________________________________________________________|____________|
   Ovary                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Leukemia Mononuclear                 |                         X  X                                            X|          6 |
      Bilateral, Granulosa-Theca Tumor     |                                                                          |            |
          Benign                           |                                           X                              |          1 |
                                            __________________________________________________________________________|____________|
   Uterus                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Leukemia Mononuclear                 |                                                                          |          3 |
      Polyp Stromal                        |                                                             X           X|          7 |
      Sarcoma Stromal                      |                               X                                          |          2 |
 _____________________________________________________________________________________________________________________|            |
 HEMATOPOIETIC SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Leukemia Mononuclear                 |                         X  X           X                                X|          8 |
                                            __________________________________________________________________________|____________|
   Lymph Node                              |                               +                                          |   3        |
      Pancreatic, Leukemia Mononuclear     |                                                                          |          2 |
      Renal, Leukemia Mononuclear          |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Bronchial                   | +  +  +  +  +  +  +  M  +  +  M  +  M  +  M  +  M  M  +  M  +  +  M  M  M|  30        |
      Leukemia Mononuclear                 |                         X  X           X                       X         |         10 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mandibular                  | +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  M  +  +  M  +  +  +  M  +|  40        |
      Leukemia Mononuclear                 |                            X           X                       X  X      |         10 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Leukemia Mononuclear                 |                         X  X           X           X           X  X     X|         13 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mediastinal                 | +  +  M  M  +  +  M  +  +  +  M  +  M  +  M  +  M  M  +  +  +  +  +  +  +|  38        |
      Leukemia Mononuclear                 |                         X  X           X                       X  X     X|         11 |
                                            __________________________________________________________________________|____________|
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
      Leukemia Mononuclear                 |                         X  X           X           X           X  X     X|         16 |
                                            __________________________________________________________________________|____________|
   Thymus                                  | +  +  M  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  45        |
 __________________________________________________________________________________________________________________________________ 

                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  

                                                             Page  12                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 4| 7| 7| 7| 6| 7| 7| 7| 7| 3| 7| 7| 7| 5| 7| 7| 7| 7| 7| 7| 7| 6| 7| 4|            |
                             DAY ON TEST   | 3| 2| 3| 3| 3| 8| 3| 3| 2| 0| 6| 3| 3| 3| 2| 3| 2| 3| 3| 3| 3| 3| 7| 3| 9|            |
                                           | 5| 0| 6| 7| 5| 7| 6| 6| 2| 9| 2| 5| 5| 6| 6| 5| 8| 7| 5| 6| 6| 6| 3| 5| 1|            |
 _____________________________________________________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     O      |
   FISCHER 344 RATS FEMALE                 | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     T      |
                               ANIMAL ID   | 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3|     A      |
    0.3                                    | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|     L      |
    MG/M3                                  | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 HEMATOPOIETIC SYSTEM - cont               |                                                                          |            |
                                           |                                                                          |            |
      Leukemia Mononuclear                 |                                                                          |          3 |
 _____________________________________________________________________________________________________________________|            |
 INTEGUMENTARY SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Mammary Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Carcinoma                            |                                           X                              |          2 |
      Fibroadenoma                         | X        X  X     X  X           X                       X  X            |         18 |
      Fibroadenoma, Multiple               |                                     X              X                     |          4 |
                                            __________________________________________________________________________|____________|
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Sebaceous Gland, Adenoma             | X                                                                        |          1 |
 _____________________________________________________________________________________________________________________|            |
 MUSCULOSKELETAL SYSTEM                    |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
 _____________________________________________________________________________________________________________________|            |
 NERVOUS SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Astrocytoma Malignant                |                                                                          |          1 |
      Leukemia Mononuclear                 |                         X                                                |          1 |
 _____________________________________________________________________________________________________________________|            |
 RESPIRATORY SYSTEM                        |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Alveolar/Bronchiolar Adenoma         |                                                                          |          1 |
      Alveolar/Bronchiolar Carcinoma       | X                                                              X         |          2 |
      Leukemia Mononuclear                 |                         X  X           X           X           X  X     X|         15 |
      Mesothelioma Malignant, Metastatic,  |                                                                          |            |
           Pleura                          |                                                                          |          1 |
      Sarcoma, Metastatic, Uncertain       |                                                                          |            |
          Primary Site                     |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Leukemia Mononuclear                 |                         X                                                |          3 |
                                            __________________________________________________________________________|____________|
   Pleura                                  |                                                                          |   1        |
      Mesothelioma Malignant               |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
 _____________________________________________________________________________________________________________________|            |
 SPECIAL SENSES SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Eye                                     |                   +     +                    +                          +|   5        |
                                            __________________________________________________________________________|____________|
   Zymbal's Gland                          |                                                                          |   1        |
      Carcinoma                            |                                                                          |          1 |
 _____________________________________________________________________________________________________________________|            |
 URINARY SYSTEM                            |                                                                          |            |
 __________________________________________________________________________________________________________________________________ 

                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  

                                                             Page  13                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 4| 7| 7| 7| 6| 7| 7| 7| 7| 3| 7| 7| 7| 5| 7| 7| 7| 7| 7| 7| 7| 6| 7| 4|            |
                             DAY ON TEST   | 3| 2| 3| 3| 3| 8| 3| 3| 2| 0| 6| 3| 3| 3| 2| 3| 2| 3| 3| 3| 3| 3| 7| 3| 9|            |
                                           | 5| 0| 6| 7| 5| 7| 6| 6| 2| 9| 2| 5| 5| 6| 6| 5| 8| 7| 5| 6| 6| 6| 3| 5| 1|            |
 _____________________________________________________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     O      |
   FISCHER 344 RATS FEMALE                 | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     T      |
                               ANIMAL ID   | 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3|     A      |
    0.3                                    | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|     L      |
    MG/M3                                  | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 URINARY SYSTEM - cont                     |                                                                          |            |
                                           |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Leukemia Mononuclear                 |                         X  X           X                       X  X     X|         11 |
      Mesenchymal Tumor Benign             |                                  X                                       |          1 |
                                            __________________________________________________________________________|____________|
   Urinary Bladder                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Leukemia Mononuclear                 |                                                                          |          1 |
 __________________________________________________________________________________________________________________________________ 
 SYSTEMIC LESIONS                          |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Multiple Organs                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Leukemia Mononuclear                 |                         X  X           X           X           X  X     X|         16 |
      Mesothelioma Malignant               |                                                                          |          1 |
 __________________________________________________________________________________________________________________________________ 

                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  

                                                             Page  14                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 7| 6| 7| 7| 7| 6| 6| 7| 7| 7| 6| 7| 5| 7| 7| 7| 6| 5| 7| 7| 7| 6| 7| 3|             
                             DAY ON TEST   | 3| 3| 9| 3| 3| 3| 3| 9| 3| 3| 3| 9| 3| 6| 3| 3| 3| 8| 9| 3| 2| 3| 5| 3| 5|             
                                           | 7| 5| 5| 6| 6| 7| 2| 4| 7| 7| 5| 2| 6| 8| 6| 7| 5| 5| 6| 7| 2| 7| 9| 6| 5|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   FISCHER 344 RATS FEMALE                 | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5|             
    1.0                                    | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
    MG/M3                                  | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 ALIMENTARY SYSTEM                         |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Esophagus                               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Colon                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Cecum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  A  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Duodenum               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Jejunum                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  A  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Ileum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  A  +  +|             
                                            __________________________________________________________________________|             
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hemangiosarcoma                      |                                                                          |             
      Histiocytic Sarcoma                  |                                                                          |             
      Leukemia Mononuclear                 |                      X     X     X              X     X     X            |             
      Pheochromocytoma Malignant,          |                                                                          |             
          Metastatic, Adrenal Medulla      |                                                    X                     |             
                                            __________________________________________________________________________|             
   Mesentery                               |    +                          +           +                    +         |             
                                            __________________________________________________________________________|             
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                                                       X                  |             
                                            __________________________________________________________________________|             
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                                                       X                  |             
                                            __________________________________________________________________________|             
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                                                       X                  |             
 _____________________________________________________________________________________________________________________|             
 CARDIOVASCULAR SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Blood Vessel                            |                                                                          |             
                                            __________________________________________________________________________|             
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                                                       X     X            |             
      Schwannoma Benign                    |                                     X                          X         |             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM                          |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                      X           X                    X     X            |             
                                            __________________________________________________________________________|             
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                      X           X                    X     X            |             
      Pheochromocytoma Malignant           |                                                    X                     |             
      Pheochromocytoma Benign              |                      X                                                   |             
                                            __________________________________________________________________________|             
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Carcinoma                            |                                                                          |             
                                            __________________________________________________________________________|             
   Parathyroid Gland                       | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Pituitary Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                      X                                X     X            |             
      Pars Distalis, Adenoma               | X  X  X  X     X  X     X     X     X     X     X  X     X  X  X  X  X   |             
                                            __________________________________________________________________________|             
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      C-Cell, Adenoma                      |             X  X           X                                   X         |             
      C-Cell, Carcinoma                    |                                                                          |             
 _____________________________________________________________________________________________________________________|             

                                                             Page  15                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 7| 6| 7| 7| 7| 6| 6| 7| 7| 7| 6| 7| 5| 7| 7| 7| 6| 5| 7| 7| 7| 6| 7| 3|             
                             DAY ON TEST   | 3| 3| 9| 3| 3| 3| 3| 9| 3| 3| 3| 9| 3| 6| 3| 3| 3| 8| 9| 3| 2| 3| 5| 3| 5|             
                                           | 7| 5| 5| 6| 6| 7| 2| 4| 7| 7| 5| 2| 6| 8| 6| 7| 5| 5| 6| 7| 2| 7| 9| 6| 5|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   FISCHER 344 RATS FEMALE                 | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5|             
    1.0                                    | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
    MG/M3                                  | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 GENERAL BODY SYSTEM                       |                                                                          |             
                                           |                                                                          |             
    None                                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 GENITAL SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Clitoral Gland                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Adenoma                              |                                                                          |             
      Carcinoma                            |                      X                                   X               |             
      Leukemia Mononuclear                 |                                                       X                  |             
      Bilateral, Adenoma                   |                                     X                                X   |             
                                            __________________________________________________________________________|             
   Ovary                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                      X           X                    X     X            |             
                                            __________________________________________________________________________|             
   Uterus                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                                                       X                  |             
      Polyp Stromal                        |                                     X                          X  X  X   |             
      Polyp Stromal, Multiple              |          X                                                               |             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                                  X                    X     X            |             
                                            __________________________________________________________________________|             
   Lymph Node                              |                                                       +                  |             
      Leukemia Mononuclear                 |                                                                          |             
      Pancreatic, Leukemia Mononuclear     |                                                                          |             
      Renal, Leukemia Mononuclear          |                                                       X                  |             
                                            __________________________________________________________________________|             
   Lymph Node, Bronchial                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                                  X                    X     X            |             
                                            __________________________________________________________________________|             
   Lymph Node, Mandibular                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                      X           X                    X     X            |             
                                            __________________________________________________________________________|             
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                      X           X                    X     X            |             
                                            __________________________________________________________________________|             
   Lymph Node, Mediastinal                 | +  M  +  +  +  +  +  +  +  M  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                      X           X                    X     X            |             
                                            __________________________________________________________________________|             
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                      X     X  X  X              X     X     X            |             
                                            __________________________________________________________________________|             
   Thymus                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +|             
      Leukemia Mononuclear                 |                                  X                    X                  |             
 _____________________________________________________________________________________________________________________|             
 INTEGUMENTARY SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Mammary Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Carcinoma                            |       X                                                        X         |             
      Fibroadenoma                         |             X                          X     X  X        X           X   |             
      Fibroadenoma, Multiple               |                                                                   X      |             
                                            __________________________________________________________________________|             
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Subcutaneous Tissue, Fibrosarcoma    |                                        X                                 |             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM                    |                                                                          |             
                                           |                                                                          |             
 _____________________________________________________________________________________________________________________|             

                                                             Page  16                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 7| 6| 7| 7| 7| 6| 6| 7| 7| 7| 6| 7| 5| 7| 7| 7| 6| 5| 7| 7| 7| 6| 7| 3|             
                             DAY ON TEST   | 3| 3| 9| 3| 3| 3| 3| 9| 3| 3| 3| 9| 3| 6| 3| 3| 3| 8| 9| 3| 2| 3| 5| 3| 5|             
                                           | 7| 5| 5| 6| 6| 7| 2| 4| 7| 7| 5| 2| 6| 8| 6| 7| 5| 5| 6| 7| 2| 7| 9| 6| 5|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   FISCHER 344 RATS FEMALE                 | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5|             
    1.0                                    | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
    MG/M3                                  | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM - cont             |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Skeletal Muscle                         |                                                                         +|             
      Rhabdomyosarcoma                     |                                                                         X|             
 _____________________________________________________________________________________________________________________|             
 NERVOUS SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Oligodendroglioma Benign             |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 RESPIRATORY SYSTEM                        |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Alveolar/Bronchiolar Adenoma         | X                                X           X           X     X         |             
      Alveolar/Bronchiolar Adenoma,        |                                                                          |             
          Multiple                         |                                                                      X   |             
      Alveolar/Bronchiolar Carcinoma       |                      X     X                 X                           |             
      Leukemia Mononuclear                 |                      X           X                    X     X            |             
      Pheochromocytoma Malignant,          |                                                                          |             
          Metastatic, Adrenal Medulla      |                                                    X                     |             
      Squamous Cell Carcinoma              |                                           X                              |             
                                            __________________________________________________________________________|             
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                                                       X     X            |             
                                            __________________________________________________________________________|             
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 SPECIAL SENSES SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Eye                                     |                               +  +                                       |             
                                            __________________________________________________________________________|             
   Zymbal's Gland                          |                                                                          |             
      Carcinoma                            |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                      X           X                    X     X            |             
                                            __________________________________________________________________________|             
   Urinary Bladder                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                                                       X                  |             
 _____________________________________________________________________________________________________________________|             
 SYSTEMIC LESIONS                          |                                                                          |             
                                            __________________________________________________________________________|             
   Multiple Organs                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Histiocytic Sarcoma                  |                                                                          |             
      Leukemia Mononuclear                 |                      X     X  X  X              X     X     X            |             
 _____________________________________________________________________________________________________________________|             

                                                             Page  17                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 6| 5| 7| 7| 5| 6| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 5| 6| 6| 7| 7|            |
                             DAY ON TEST   | 0| 4| 2| 3| 2| 5| 3| 3| 3| 3| 2| 2| 3| 2| 2| 0| 3| 3| 3| 3| 1| 1| 0| 3| 3|            |
                                           | 0| 1| 2| 6| 6| 2| 6| 6| 7| 2| 2| 9| 6| 3| 7| 9| 6| 6| 6| 7| 0| 9| 3| 5| 5|            |
 _____________________________________________________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     O      |
   FISCHER 344 RATS FEMALE                 | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     T      |
                               ANIMAL ID   | 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5|     A      |
    1.0                                    | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|     L      |
    MG/M3                                  | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 ALIMENTARY SYSTEM                         |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Esophagus                               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Colon                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|  48        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Cecum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|  47        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Duodenum               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|  48        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Jejunum                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|  47        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Ileum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|  47        |
                                            __________________________________________________________________________|____________|
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hemangiosarcoma                      |                                                                      X   |          1 |
      Histiocytic Sarcoma                  |          X                                                               |          1 |
      Leukemia Mononuclear                 | X     X  X  X  X  X  X     X  X              X     X           X         |         18 |
      Pheochromocytoma Malignant,          |                                                                          |            |
          Metastatic, Adrenal Medulla      |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Mesentery                               |                +                                      +                  |   6        |
                                            __________________________________________________________________________|____________|
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|  49        |
      Leukemia Mononuclear                 |                                                                          |          1 |
 _____________________________________________________________________________________________________________________|            |
 CARDIOVASCULAR SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Blood Vessel                            |                                                             +            |   1        |
                                            __________________________________________________________________________|____________|
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |             X                 X              X                           |          5 |
      Schwannoma Benign                    |                                                                          |          2 |
 _____________________________________________________________________________________________________________________|            |
 ENDOCRINE SYSTEM                          |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |       X     X                 X              X                 X         |          9 |
                                            __________________________________________________________________________|____________|
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |       X     X                                X                 X         |          8 |
      Pheochromocytoma Malignant           |                                                                          |          1 |
      Pheochromocytoma Benign              |                               X                                      X   |          3 |
                                            __________________________________________________________________________|____________|
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Carcinoma                            |                                           X                              |          1 |
                                            __________________________________________________________________________|____________|
   Parathyroid Gland                       | +  +  +  +  +  M  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
                                            __________________________________________________________________________|____________|
   Pituitary Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 __________________________________________________________________________________________________________________________________ 

                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  

                                                             Page  18                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 6| 5| 7| 7| 5| 6| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 5| 6| 6| 7| 7|            |
                             DAY ON TEST   | 0| 4| 2| 3| 2| 5| 3| 3| 3| 3| 2| 2| 3| 2| 2| 0| 3| 3| 3| 3| 1| 1| 0| 3| 3|            |
                                           | 0| 1| 2| 6| 6| 2| 6| 6| 7| 2| 2| 9| 6| 3| 7| 9| 6| 6| 6| 7| 0| 9| 3| 5| 5|            |
 _____________________________________________________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     O      |
   FISCHER 344 RATS FEMALE                 | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     T      |
                               ANIMAL ID   | 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5|     A      |
    1.0                                    | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|     L      |
    MG/M3                                  | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 ENDOCRINE SYSTEM - cont                   |                                                                          |            |
                                           |                                                                          |            |
      Leukemia Mononuclear                 |             X                                X                 X         |          6 |
      Pars Distalis, Adenoma               |    X  X  X     X  X  X  X  X  X  X     X  X  X  X  X  X  X  X  X     X  X|         38 |
                                            __________________________________________________________________________|____________|
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      C-Cell, Adenoma                      |                               X  X                                   X   |          7 |
      C-Cell, Carcinoma                    |                            X                 X                           |          2 |
 _____________________________________________________________________________________________________________________|            |
 GENERAL BODY SYSTEM                       |                                                                          |            |
                                           |                                                                          |            |
    None                                   |                                                                          |            |
 _____________________________________________________________________________________________________________________|            |
 GENITAL SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Clitoral Gland                          | +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  M  +  +|  48        |
      Adenoma                              |                      X     X              X                              |          3 |
      Carcinoma                            |                                           X                             X|          4 |
      Leukemia Mononuclear                 |                                                                          |          1 |
      Bilateral, Adenoma                   |                                                                          |          2 |
                                            __________________________________________________________________________|____________|
   Ovary                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |                                                                X         |          5 |
                                            __________________________________________________________________________|____________|
   Uterus                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |                                              X                           |          2 |
      Polyp Stromal                        | X        X           X              X              X              X      |         10 |
      Polyp Stromal, Multiple              |                                                                          |          1 |
 _____________________________________________________________________________________________________________________|            |
 HEMATOPOIETIC SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 | X                 X        X  X              X                 X         |          9 |
                                            __________________________________________________________________________|____________|
   Lymph Node                              |                                              +                 +         |   3        |
      Leukemia Mononuclear                 |                                              X                           |          1 |
      Pancreatic, Leukemia Mononuclear     |                                              X                 X         |          2 |
      Renal, Leukemia Mononuclear          |                                              X                           |          2 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Bronchial                   | +  +  +  +  +  M  +  +  M  M  +  +  M  M  M  +  M  M  +  M  M  M  +  M  M|  37        |
      Leukemia Mononuclear                 |             X     X           X              X                           |          7 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mandibular                  | +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  M  +  +  +  M|  47        |
      Leukemia Mononuclear                 |             X  X  X        X  X              X     X           X         |         12 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 | X        X  X  X  X  X     X  X              X     X           X         |         15 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mediastinal                 | +  +  +  +  +  +  +  +  M  +  +  +  M  +  +  +  +  +  +  +  +  +  M  M  +|  43        |
      Leukemia Mononuclear                 | X           X  X  X           X              X     X           X         |         12 |
                                            __________________________________________________________________________|____________|
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 | X     X  X  X  X  X  X     X  X              X     X           X         |         19 |
 __________________________________________________________________________________________________________________________________ 

                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  

                                                             Page  19                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 6| 5| 7| 7| 5| 6| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 5| 6| 6| 7| 7|            |
                             DAY ON TEST   | 0| 4| 2| 3| 2| 5| 3| 3| 3| 3| 2| 2| 3| 2| 2| 0| 3| 3| 3| 3| 1| 1| 0| 3| 3|            |
                                           | 0| 1| 2| 6| 6| 2| 6| 6| 7| 2| 2| 9| 6| 3| 7| 9| 6| 6| 6| 7| 0| 9| 3| 5| 5|            |
 _____________________________________________________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     O      |
   FISCHER 344 RATS FEMALE                 | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     T      |
                               ANIMAL ID   | 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5|     A      |
    1.0                                    | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|     L      |
    MG/M3                                  | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 HEMATOPOIETIC SYSTEM - cont               |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Thymus                                  | +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  M  M  +  +  +  +  M  +  +  +|  45        |
      Leukemia Mononuclear                 |                X                                                         |          3 |
 _____________________________________________________________________________________________________________________|            |
 INTEGUMENTARY SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Mammary Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Carcinoma                            |       X           X                    X                                 |          5 |
      Fibroadenoma                         |       X  X                    X                    X        X     X     X|         13 |
      Fibroadenoma, Multiple               |                      X              X     X     X     X        X         |          7 |
                                            __________________________________________________________________________|____________|
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Subcutaneous Tissue, Fibrosarcoma    |                                                                          |          1 |
 _____________________________________________________________________________________________________________________|            |
 MUSCULOSKELETAL SYSTEM                    |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Skeletal Muscle                         |                                                                          |   1        |
      Rhabdomyosarcoma                     |                                                                          |          1 |
 _____________________________________________________________________________________________________________________|            |
 NERVOUS SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Oligodendroglioma Benign             |                                        X                                 |          1 |
 _____________________________________________________________________________________________________________________|            |
 RESPIRATORY SYSTEM                        |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Alveolar/Bronchiolar Adenoma         |          X           X  X                          X                     |          9 |
      Alveolar/Bronchiolar Adenoma,        |                                                                          |            |
          Multiple                         |                                                                          |          1 |
      Alveolar/Bronchiolar Carcinoma       |                                              X        X                 X|          6 |
      Leukemia Mononuclear                 | X     X  X  X  X  X        X  X              X     X           X         |         15 |
      Pheochromocytoma Malignant,          |                                                                          |            |
          Metastatic, Adrenal Medulla      |                                                                          |          1 |
      Squamous Cell Carcinoma              |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |                                                                          |          2 |
                                            __________________________________________________________________________|____________|
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 SPECIAL SENSES SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Eye                                     |                   +                                                      |   3        |
                                            __________________________________________________________________________|____________|
   Zymbal's Gland                          |                                           +                              |   1        |
      Carcinoma                            |                                           X                              |          1 |
 __________________________________________________________________________________________________________________________________ 

                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  

                                                             Page  20                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 6| 5| 7| 7| 5| 6| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 5| 6| 6| 7| 7|            |
                             DAY ON TEST   | 0| 4| 2| 3| 2| 5| 3| 3| 3| 3| 2| 2| 3| 2| 2| 0| 3| 3| 3| 3| 1| 1| 0| 3| 3|            |
                                           | 0| 1| 2| 6| 6| 2| 6| 6| 7| 2| 2| 9| 6| 3| 7| 9| 6| 6| 6| 7| 0| 9| 3| 5| 5|            |
 _____________________________________________________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     O      |
   FISCHER 344 RATS FEMALE                 | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     T      |
                               ANIMAL ID   | 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5|     A      |
    1.0                                    | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|     L      |
    MG/M3                                  | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 SPECIAL SENSES SYSTEM - cont              |                                                                          |            |
                                           |                                                                          |            |
 _____________________________________________________________________________________________________________________|            |
 URINARY SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |       X  X  X  X  X        X  X              X     X           X         |         14 |
                                            __________________________________________________________________________|____________|
   Urinary Bladder                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |                               X              X                           |          3 |
 __________________________________________________________________________________________________________________________________ 
 SYSTEMIC LESIONS                          |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Multiple Organs                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Histiocytic Sarcoma                  |          X                                                               |          1 |
      Leukemia Mononuclear                 | X     X  X  X  X  X  X     X  X              X     X           X         |         19 |
 __________________________________________________________________________________________________________________________________ 

                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  

                                                             Page  21                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 5| 7| 7| 6| 7| 7| 6| 6| 6| 7| 6| 7| 7| 7| 7| 7| 6| 7| 7| 7| 6| 7| 7| 7| 7|             
                             DAY ON TEST   | 8| 3| 3| 9| 3| 3| 5| 8| 9| 0| 7| 3| 3| 3| 3| 3| 4| 3| 3| 3| 1| 3| 3| 3| 3|             
                                           | 5| 6| 6| 2| 6| 6| 0| 6| 3| 9| 9| 5| 7| 7| 6| 5| 2| 5| 5| 6| 1| 7| 6| 6| 6|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   FISCHER 344 RATS FEMALE                 | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7|             
    3.0                                    | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
    MG/M3                                  | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 ALIMENTARY SYSTEM                         |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Esophagus                               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Colon                  | A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                                                                          |             
                                            __________________________________________________________________________|             
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Cecum                  | A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                                                                          |             
                                            __________________________________________________________________________|             
   Intestine Small, Duodenum               | A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Jejunum                | A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Ileum                  | A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                                     X                                    |             
                                            __________________________________________________________________________|             
   Liver                                   | A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                      X  X           X                 X     X            |             
                                            __________________________________________________________________________|             
   Mesentery                               | +     +                       +           +        +              +      |             
                                            __________________________________________________________________________|             
   Pancreas                                | A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                      X              X                                    |             
                                            __________________________________________________________________________|             
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Adenoma                              |                                                                          |             
      Sarcoma, Metastatic, Eye             |                                                 X                        |             
                                            __________________________________________________________________________|             
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leiomyoma                            |                                                                          |             
      Leukemia Mononuclear                 |                                     X                                    |             
                                            __________________________________________________________________________|             
   Stomach, Glandular                      | A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Tooth                                   |                                              +                           |             
 _____________________________________________________________________________________________________________________|             
 CARDIOVASCULAR SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Carcinoma, Metastatic, Lung          |                                                                          |             
      Leukemia Mononuclear                 |                                                                          |             
      Schwannoma Benign                    |                                                       X                  |             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM                          |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Adrenal Cortex                          | A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Adenoma                              |                                                                          |             
      Leukemia Mononuclear                 |                      X              X                                    |             
                                            __________________________________________________________________________|             
   Adrenal Medulla                         | A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +|             
      Leukemia Mononuclear                 |                      X              X                                    |             
      Pheochromocytoma Malignant           |                                                                          |             
      Pheochromocytoma Complex             |                                                                          |             
      Pheochromocytoma Benign              |                X                    X                    X               |             
      Bilateral, Pheochromocytoma Benign   |                                                                          |             
                                            __________________________________________________________________________|             
   Islets, Pancreatic                      | A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Parathyroid Gland                       | A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Pituitary Gland                         | A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                      X              X                                    |             
 _____________________________________________________________________________________________________________________|             

                                                             Page  22                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 5| 7| 7| 6| 7| 7| 6| 6| 6| 7| 6| 7| 7| 7| 7| 7| 6| 7| 7| 7| 6| 7| 7| 7| 7|             
                             DAY ON TEST   | 8| 3| 3| 9| 3| 3| 5| 8| 9| 0| 7| 3| 3| 3| 3| 3| 4| 3| 3| 3| 1| 3| 3| 3| 3|             
                                           | 5| 6| 6| 2| 6| 6| 0| 6| 3| 9| 9| 5| 7| 7| 6| 5| 2| 5| 5| 6| 1| 7| 6| 6| 6|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   FISCHER 344 RATS FEMALE                 | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7|             
    3.0                                    | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
    MG/M3                                  | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM - cont                   |                                                                          |             
                                           |                                                                          |             
      Pars Distalis, Adenoma               |    X     X     X  X  X  X  X  X     X  X     X  X  X  X  X  X  X  X  X  X|             
                                            __________________________________________________________________________|             
   Thyroid Gland                           | A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +|             
      C-Cell, Adenoma                      |                            X                                X            |             
      C-Cell, Carcinoma                    |                X     X                                            X      |             
      Follicular Cell, Adenoma             |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 GENERAL BODY SYSTEM                       |                                                                          |             
                                           |                                                                          |             
    None                                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 GENITAL SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Clitoral Gland                          | +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Adenoma                              |                                                                          |             
      Carcinoma                            |                                                                          |             
                                            __________________________________________________________________________|             
   Ovary                                   | A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                                     X                                    |             
                                            __________________________________________________________________________|             
   Uterus                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Histiocytic Sarcoma                  |                      X                                                   |             
      Leiomyoma                            |                                                                          |             
      Polyp Stromal                        |                                  X           X                           |             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                      X              X                                    |             
                                            __________________________________________________________________________|             
   Lymph Node                              |                                                                          |             
      Pancreatic, Leukemia Mononuclear     |                                                                          |             
                                            __________________________________________________________________________|             
   Lymph Node, Bronchial                   | +  M  +  +  +  +  +  +  M  +  +  M  +  M  +  M  M  +  +  +  +  M  +  +  +|             
      Leukemia Mononuclear                 |                      X                                                   |             
                                            __________________________________________________________________________|             
   Lymph Node, Mandibular                  | +  M  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  M  M  +  +  +  +  +|             
      Leukemia Mononuclear                 |                                     X                                    |             
      Sarcoma, Metastatic, Eye             |                                                 X                        |             
      Sarcoma, Metastatic, Skin            |                                                                          |             
                                            __________________________________________________________________________|             
   Lymph Node, Mesenteric                  | A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                      X              X                                    |             
                                            __________________________________________________________________________|             
   Lymph Node, Mediastinal                 | +  +  +  +  +  +  +  +  M  +  +  M  M  +  +  M  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                      X                                                   |             
                                            __________________________________________________________________________|             
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Histiocytic Sarcoma                  |                      X                                                   |             
      Leukemia Mononuclear                 |                      X  X           X                 X     X            |             
                                            __________________________________________________________________________|             
   Thymus                                  | A  M  +  +  +  +  +  +  +  +  +  +  M  +  +  M  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                      X                                                   |             
      Lymphoma Malignant                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 INTEGUMENTARY SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Mammary Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             

                                                             Page  23                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 5| 7| 7| 6| 7| 7| 6| 6| 6| 7| 6| 7| 7| 7| 7| 7| 6| 7| 7| 7| 6| 7| 7| 7| 7|             
                             DAY ON TEST   | 8| 3| 3| 9| 3| 3| 5| 8| 9| 0| 7| 3| 3| 3| 3| 3| 4| 3| 3| 3| 1| 3| 3| 3| 3|             
                                           | 5| 6| 6| 2| 6| 6| 0| 6| 3| 9| 9| 5| 7| 7| 6| 5| 2| 5| 5| 6| 1| 7| 6| 6| 6|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   FISCHER 344 RATS FEMALE                 | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7|             
    3.0                                    | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
    MG/M3                                  | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 INTEGUMENTARY SYSTEM - cont               |                                                                          |             
                                           |                                                                          |             
      Carcinoma                            |    X                                                                     |             
      Carcinoma, Multiple                  |                         X                                                |             
      Fibroadenoma                         |    X  X           X        X        X  X        X  X  X  X               |             
      Fibroadenoma, Multiple               |          X     X                 X        X                              |             
                                            __________________________________________________________________________|             
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Basal Cell Adenoma                   |                                                                          |             
      Sebaceous Gland, Adenoma             |                                                                          |             
      Subcutaneous Tissue, Fibroma         |                                                                          |             
      Subcutaneous Tissue, Sarcoma         |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM                    |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Sarcoma, Metastatic, Eye             |                                                 X                        |             
                                            __________________________________________________________________________|             
   Skeletal Muscle                         |                                                                          |             
      Carcinoma, Metastatic, Lung          |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 NERVOUS SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Astrocytoma Benign                   |                   X                                                      |             
      Leukemia Mononuclear                 |                                     X                                    |             
 _____________________________________________________________________________________________________________________|             
 RESPIRATORY SYSTEM                        |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Alveolar/Bronchiolar Adenoma         |                                                    X              X     X|             
      Alveolar/Bronchiolar Adenoma,        |                                                                          |             
          Multiple                         |                                  X  X                                    |             
      Alveolar/Bronchiolar Carcinoma       |    X                                                           X         |             
      Histiocytic Sarcoma                  |                      X                                                   |             
      Leukemia Mononuclear                 |                      X  X           X                                    |             
      Sarcoma, Metastatic, Eye             |                                                 X                        |             
      Sarcoma, Metastatic, Skin            |                                                                          |             
      Squamous Cell Carcinoma              |                                                                          |             
      Mediastinum, Alveolar/Bronchiolar    |                                                                          |             
          Carcinoma, Metastatic, Lung      |                                                                          |             
                                            __________________________________________________________________________|             
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                      X              X                                    |             
                                            __________________________________________________________________________|             
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 SPECIAL SENSES SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Eye                                     |    +                                            +                        |             
      Sarcoma                              |                                                 X                        |             
                                            __________________________________________________________________________|             
   Lacrimal Gland                          |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM                            |                                                                          |             
 _____________________________________________________________________________________________________________________|             

                                                             Page  24                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 5| 7| 7| 6| 7| 7| 6| 6| 6| 7| 6| 7| 7| 7| 7| 7| 6| 7| 7| 7| 6| 7| 7| 7| 7|             
                             DAY ON TEST   | 8| 3| 3| 9| 3| 3| 5| 8| 9| 0| 7| 3| 3| 3| 3| 3| 4| 3| 3| 3| 1| 3| 3| 3| 3|             
                                           | 5| 6| 6| 2| 6| 6| 0| 6| 3| 9| 9| 5| 7| 7| 6| 5| 2| 5| 5| 6| 1| 7| 6| 6| 6|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   FISCHER 344 RATS FEMALE                 | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7|             
    3.0                                    | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
    MG/M3                                  | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM - cont                     |                                                                          |             
                                           |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Kidney                                  | A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Histiocytic Sarcoma                  |                      X                                                   |             
      Leukemia Mononuclear                 |                      X              X                                    |             
      Lipoma                               |                                                          X               |             
                                            __________________________________________________________________________|             
   Urinary Bladder                         | A  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 SYSTEMIC LESIONS                          |                                                                          |             
                                            __________________________________________________________________________|             
   Multiple Organs                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Histiocytic Sarcoma                  |                      X                                                   |             
      Leukemia Mononuclear                 |                      X  X           X                 X     X            |             
      Lymphoma Malignant                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             

                                                             Page  25                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 6| 7| 7| 7| 3| 7| 7| 6| 7| 7| 6| 7| 7| 7| 7| 7| 4| 0| 6| 7| 7| 6| 7| 6| 7|            |
                             DAY ON TEST   | 5| 3| 3| 2| 8| 3| 3| 7| 3| 3| 3| 3| 3| 0| 3| 3| 7| 0| 8| 3| 3| 6| 3| 1| 3|            |
                                           | 2| 7| 5| 2| 6| 6| 6| 3| 7| 5| 2| 7| 5| 9| 7| 7| 0| 6| 0| 6| 6| 3| 7| 0| 6|            |
 _____________________________________________________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     O      |
   FISCHER 344 RATS FEMALE                 | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     T      |
                               ANIMAL ID   | 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7|     A      |
    3.0                                    | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|     L      |
    MG/M3                                  | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 ALIMENTARY SYSTEM                         |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Esophagus                               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Colon                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  48        |
      Leukemia Mononuclear                 |          X                                                               |          1 |
                                            __________________________________________________________________________|____________|
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Cecum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  47        |
      Leukemia Mononuclear                 |          X                                                               |          1 |
                                            __________________________________________________________________________|____________|
   Intestine Small, Duodenum               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  48        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Jejunum                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  47        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Ileum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  47        |
      Leukemia Mononuclear                 |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Leukemia Mononuclear                 |          X                             X     X  X              X         |         10 |
                                            __________________________________________________________________________|____________|
   Mesentery                               |    +              +              +           +        +     +        +   |  13        |
                                            __________________________________________________________________________|____________|
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  48        |
      Leukemia Mononuclear                 |                                                                          |          2 |
                                            __________________________________________________________________________|____________|
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Adenoma                              |                                              X                           |          1 |
      Sarcoma, Metastatic, Eye             |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leiomyoma                            |                                                             X            |          1 |
      Leukemia Mononuclear                 |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  48        |
                                            __________________________________________________________________________|____________|
   Tooth                                   |                                                                          |   1        |
 _____________________________________________________________________________________________________________________|            |
 CARDIOVASCULAR SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Carcinoma, Metastatic, Lung          |                                                                      X   |          1 |
      Leukemia Mononuclear                 |                                                                X         |          1 |
      Schwannoma Benign                    |                                                                          |          1 |
 _____________________________________________________________________________________________________________________|            |
 ENDOCRINE SYSTEM                          |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Adenoma                              |                                     X                                    |          1 |
      Leukemia Mononuclear                 |          X                             X                       X         |          5 |
                                            __________________________________________________________________________|____________|
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
      Leukemia Mononuclear                 |          X                             X                       X         |          5 |
      Pheochromocytoma Malignant           |                                                                X         |          1 |
      Pheochromocytoma Complex             |                   X                                                      |          1 |
      Pheochromocytoma Benign              |    X  X                                X  X                              |          7 |
 __________________________________________________________________________________________________________________________________ 

                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  

                                                             Page  26                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 6| 7| 7| 7| 3| 7| 7| 6| 7| 7| 6| 7| 7| 7| 7| 7| 4| 0| 6| 7| 7| 6| 7| 6| 7|            |
                             DAY ON TEST   | 5| 3| 3| 2| 8| 3| 3| 7| 3| 3| 3| 3| 3| 0| 3| 3| 7| 0| 8| 3| 3| 6| 3| 1| 3|            |
                                           | 2| 7| 5| 2| 6| 6| 6| 3| 7| 5| 2| 7| 5| 9| 7| 7| 0| 6| 0| 6| 6| 3| 7| 0| 6|            |
 _____________________________________________________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     O      |
   FISCHER 344 RATS FEMALE                 | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     T      |
                               ANIMAL ID   | 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7|     A      |
    3.0                                    | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|     L      |
    MG/M3                                  | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 ENDOCRINE SYSTEM - cont                   |                                                                          |            |
                                           |                                                                          |            |
      Bilateral, Pheochromocytoma Benign   |                                  X                                       |          1 |
                                            __________________________________________________________________________|____________|
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  48        |
                                            __________________________________________________________________________|____________|
   Parathyroid Gland                       | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +|  47        |
                                            __________________________________________________________________________|____________|
   Pituitary Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Leukemia Mononuclear                 |          X                                                               |          3 |
      Pars Distalis, Adenoma               | X  X  X  X  X  X  X     X  X  X  X  X     X  X        X  X  X  X  X     X|         40 |
                                            __________________________________________________________________________|____________|
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
      C-Cell, Adenoma                      |                   X                                                      |          3 |
      C-Cell, Carcinoma                    |                                                                          |          3 |
      Follicular Cell, Adenoma             | X                                                                        |          1 |
 _____________________________________________________________________________________________________________________|            |
 GENERAL BODY SYSTEM                       |                                                                          |            |
                                           |                                                                          |            |
    None                                   |                                                                          |            |
 _____________________________________________________________________________________________________________________|            |
 GENITAL SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Clitoral Gland                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Adenoma                              |                   X                    X              X                  |          3 |
      Carcinoma                            |                                     X                       X           X|          3 |
                                            __________________________________________________________________________|____________|
   Ovary                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Leukemia Mononuclear                 |          X                             X                                 |          3 |
                                            __________________________________________________________________________|____________|
   Uterus                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  49        |
      Histiocytic Sarcoma                  |                                                                          |          1 |
      Leiomyoma                            |                                                             X            |          1 |
      Polyp Stromal                        |       X                          X                                       |          4 |
 _____________________________________________________________________________________________________________________|            |
 HEMATOPOIETIC SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |                                        X        X                        |          4 |
                                            __________________________________________________________________________|____________|
   Lymph Node                              |          +                             +                                 |   2        |
      Pancreatic, Leukemia Mononuclear     |          X                             X                                 |          2 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Bronchial                   | +  +  +  +  +  M  +  +  +  +  +  +  +  M  +  +  +  M  M  +  +  M  M  +  +|  37        |
      Leukemia Mononuclear                 |          X                                                               |          2 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mandibular                  | +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +|  45        |
      Leukemia Mononuclear                 |          X                             X                       X         |          4 |
      Sarcoma, Metastatic, Eye             |                                                                          |          1 |
      Sarcoma, Metastatic, Skin            |                               X                                          |          1 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  48        |
      Leukemia Mononuclear                 |          X                             X                       X         |          5 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mediastinal                 | +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +|  45        |
 __________________________________________________________________________________________________________________________________ 

                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  

                                                             Page  27                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 6| 7| 7| 7| 3| 7| 7| 6| 7| 7| 6| 7| 7| 7| 7| 7| 4| 0| 6| 7| 7| 6| 7| 6| 7|            |
                             DAY ON TEST   | 5| 3| 3| 2| 8| 3| 3| 7| 3| 3| 3| 3| 3| 0| 3| 3| 7| 0| 8| 3| 3| 6| 3| 1| 3|            |
                                           | 2| 7| 5| 2| 6| 6| 6| 3| 7| 5| 2| 7| 5| 9| 7| 7| 0| 6| 0| 6| 6| 3| 7| 0| 6|            |
 _____________________________________________________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     O      |
   FISCHER 344 RATS FEMALE                 | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     T      |
                               ANIMAL ID   | 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7|     A      |
    3.0                                    | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|     L      |
    MG/M3                                  | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 HEMATOPOIETIC SYSTEM - cont               |                                                                          |            |
                                           |                                                                          |            |
      Leukemia Mononuclear                 |          X                                      X              X         |          4 |
                                            __________________________________________________________________________|____________|
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  49        |
      Histiocytic Sarcoma                  |                                                                          |          1 |
      Leukemia Mononuclear                 |          X                             X     X  X              X         |         10 |
                                            __________________________________________________________________________|____________|
   Thymus                                  | +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +|  44        |
      Leukemia Mononuclear                 |                                        X                       X         |          3 |
      Lymphoma Malignant                   |       X                                                                  |          1 |
 _____________________________________________________________________________________________________________________|            |
 INTEGUMENTARY SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Mammary Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +|  49        |
      Carcinoma                            |                   X              X        X                              |          4 |
      Carcinoma, Multiple                  |                                                                          |          1 |
      Fibroadenoma                         | X     X  X  X     X     X              X  X              X        X      |         20 |
      Fibroadenoma, Multiple               |                            X                                X           X|          7 |
                                            __________________________________________________________________________|____________|
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Basal Cell Adenoma                   |          X                                                               |          1 |
      Sebaceous Gland, Adenoma             |       X                                                                  |          1 |
      Subcutaneous Tissue, Fibroma         |                X                                                         |          1 |
      Subcutaneous Tissue, Sarcoma         |                               X                                          |          1 |
 _____________________________________________________________________________________________________________________|            |
 MUSCULOSKELETAL SYSTEM                    |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Sarcoma, Metastatic, Eye             |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Skeletal Muscle                         |                                                                      +   |   1        |
      Carcinoma, Metastatic, Lung          |                                                                      X   |          1 |
 _____________________________________________________________________________________________________________________|            |
 NERVOUS SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Astrocytoma Benign                   |                                                                          |          1 |
      Leukemia Mononuclear                 |                                                                          |          1 |
 _____________________________________________________________________________________________________________________|            |
 RESPIRATORY SYSTEM                        |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Alveolar/Bronchiolar Adenoma         |       X                          X           X                    X      |          7 |
      Alveolar/Bronchiolar Adenoma,        |                                                                          |            |
          Multiple                         |                                                                          |          2 |
      Alveolar/Bronchiolar Carcinoma       |                            X                          X              X  X|          6 |
      Histiocytic Sarcoma                  |                                                                          |          1 |
 __________________________________________________________________________________________________________________________________ 

                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  

                                                             Page  28                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 6| 7| 7| 7| 3| 7| 7| 6| 7| 7| 6| 7| 7| 7| 7| 7| 4| 0| 6| 7| 7| 6| 7| 6| 7|            |
                             DAY ON TEST   | 5| 3| 3| 2| 8| 3| 3| 7| 3| 3| 3| 3| 3| 0| 3| 3| 7| 0| 8| 3| 3| 6| 3| 1| 3|            |
                                           | 2| 7| 5| 2| 6| 6| 6| 3| 7| 5| 2| 7| 5| 9| 7| 7| 0| 6| 0| 6| 6| 3| 7| 0| 6|            |
 _____________________________________________________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     O      |
   FISCHER 344 RATS FEMALE                 | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     T      |
                               ANIMAL ID   | 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7|     A      |
    3.0                                    | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|     L      |
    MG/M3                                  | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 RESPIRATORY SYSTEM - cont                 |                                                                          |            |
                                           |                                                                          |            |
      Leukemia Mononuclear                 |          X                             X        X              X         |          7 |
      Sarcoma, Metastatic, Eye             |                                                                          |          1 |
      Sarcoma, Metastatic, Skin            |                               X                                          |          1 |
      Squamous Cell Carcinoma              |                         X                                                |          1 |
      Mediastinum, Alveolar/Bronchiolar    |                                                                          |            |
          Carcinoma, Metastatic, Lung      |                                                                      X   |          1 |
                                            __________________________________________________________________________|____________|
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |                                                                          |          2 |
                                            __________________________________________________________________________|____________|
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 SPECIAL SENSES SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Eye                                     |                                                                      +   |   3        |
      Sarcoma                              |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Lacrimal Gland                          |    +                                      +                              |   2        |
 _____________________________________________________________________________________________________________________|            |
 URINARY SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  48        |
      Histiocytic Sarcoma                  |                                                                          |          1 |
      Leukemia Mononuclear                 |          X                             X        X              X         |          6 |
      Lipoma                               |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Urinary Bladder                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  47        |
      Leukemia Mononuclear                 |          X                                                               |          1 |
 __________________________________________________________________________________________________________________________________ 
 SYSTEMIC LESIONS                          |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Multiple Organs                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Histiocytic Sarcoma                  |                                                                          |          1 |
      Leukemia Mononuclear                 |          X                             X     X  X              X         |         10 |
      Lymphoma Malignant                   |       X                                                                  |          1 |
 __________________________________________________________________________________________________________________________________ 

                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  

                                                             Page  29                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 7| 6| 5| 7| 7| 7| 6| 7| 7| 7| 5| 7| 5| 4| 5| 6| 6| 7| 7| 6| 4| 6| 6| 7|             
                             DAY ON TEST   | 3| 3| 3| 8| 3| 3| 3| 9| 3| 3| 3| 8| 3| 3| 5| 2| 3| 7| 3| 3| 0| 3| 8| 0| 3|             
                                           | 4| 5| 1| 2| 4| 4| 4| 1| 4| 4| 4| 9| 5| 4| 3| 7| 2| 9| 4| 4| 2| 5| 0| 3| 5|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   FISCHER 344 RATS MALE                   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
    CONTROL                                | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
                                           | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 ALIMENTARY SYSTEM                         |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Esophagus                               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Colon                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Cecum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Duodenum               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Jejunum                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Ileum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hepatocellular Adenoma               |                X                                                         |             
      Leukemia Mononuclear                 |    X  X  X  X  X        X                 X  X  X  X     X  X     X  X   |             
                                            __________________________________________________________________________|             
   Mesentery                               | +        +     +              +     +     +              +              +|             
      Leukemia Mononuclear                 |                                           X                              |             
                                            __________________________________________________________________________|             
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |       X                                                                  |             
                                            __________________________________________________________________________|             
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                                           X        X                     |             
                                            __________________________________________________________________________|             
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                                           X                              |             
                                            __________________________________________________________________________|             
   Tongue                                  |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 CARDIOVASCULAR SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |       X  X     X                          X                          X   |             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM                          |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |    X  X  X              X                 X  X  X  X     X  X        X   |             
                                            __________________________________________________________________________|             
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |       X  X              X                 X     X  X     X  X        X   |             
      Pheochromocytoma Complex             |                                                                          |             
      Pheochromocytoma Benign              |          X              X  X     X  X  X        X        X        X     X|             
      Bilateral, Pheochromocytoma Benign   |                                                                          |             
                                            __________________________________________________________________________|             
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Adenoma                              |                                                    X                     |             
      Adenoma, Multiple                    |                         X                                                |             
      Carcinoma                            |                                                                          |             
                                            __________________________________________________________________________|             
   Parathyroid Gland                       | +  +  +  +  +  +  +  +  +  +  M  +  M  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Pituitary Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |       X  X     X                          X        X     X  X        X   |             
      Pars Distalis, Adenoma               | X  X     X  X  X  X  X  X  X  X  X  X  X  X  X  X  X  X  X  X  X  X     X|             
                                            __________________________________________________________________________|             
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +|             
      C-Cell, Adenoma                      |                   X     X                                                |             
      C-Cell, Carcinoma                    |                      X        X                                X         |             
 _____________________________________________________________________________________________________________________|             

                                                             Page  30                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 7| 6| 5| 7| 7| 7| 6| 7| 7| 7| 5| 7| 5| 4| 5| 6| 6| 7| 7| 6| 4| 6| 6| 7|             
                             DAY ON TEST   | 3| 3| 3| 8| 3| 3| 3| 9| 3| 3| 3| 8| 3| 3| 5| 2| 3| 7| 3| 3| 0| 3| 8| 0| 3|             
                                           | 4| 5| 1| 2| 4| 4| 4| 1| 4| 4| 4| 9| 5| 4| 3| 7| 2| 9| 4| 4| 2| 5| 0| 3| 5|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   FISCHER 344 RATS MALE                   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
    CONTROL                                | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
                                           | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM - cont                   |                                                                          |             
                                           |                                                                          |             
      Follicular Cell, Carcinoma           |                                     X                                    |             
 _____________________________________________________________________________________________________________________|             
 GENERAL BODY SYSTEM                       |                                                                          |             
                                           |                                                                          |             
    None                                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 GENITAL SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Epididymis                              | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Mesothelioma Malignant               |       X                          X                                       |             
                                            __________________________________________________________________________|             
   Penis                                   |       +                                   +                              |             
                                            __________________________________________________________________________|             
   Preputial Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Carcinoma                            |                      X                             X                     |             
      Leukemia Mononuclear                 |          X                                                               |             
      Bilateral, Carcinoma                 |                                                                          |             
                                            __________________________________________________________________________|             
   Prostate                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Adenoma                              |                               X                                          |             
                                            __________________________________________________________________________|             
   Seminal Vesicle                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |       X  X     X                                                     X   |             
                                            __________________________________________________________________________|             
   Testes                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Mesothelioma Malignant               |       X                          X                                       |             
      Bilateral, Interstitial Cell, Adenoma| X  X     X     X  X  X  X  X  X     X              X     X  X           X|             
      Interstitial Cell, Adenoma           |             X                                         X              X   |             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |       X  X     X        X                 X     X  X     X  X        X   |             
                                            __________________________________________________________________________|             
   Lymph Node                              |       +                                   +                          +   |             
      Leukemia Mononuclear                 |       X                                                                  |             
      Deep Cervical, Leukemia Mononuclear  |       X                                                                  |             
      Iliac, Leukemia Mononuclear          |       X                                                                  |             
      Pancreatic, Leukemia Mononuclear     |       X                                   X                          X   |             
      Renal, Leukemia Mononuclear          |       X                                   X                              |             
                                            __________________________________________________________________________|             
   Lymph Node, Bronchial                   | +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |       X  X     X        X                 X  X  X  X     X  X     X  X   |             
                                            __________________________________________________________________________|             
   Lymph Node, Mandibular                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |       X  X     X        X                 X  X  X        X  X        X   |             
                                            __________________________________________________________________________|             
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |       X  X     X        X                 X  X  X  X     X  X     X  X   |             
                                            __________________________________________________________________________|             
   Lymph Node, Mediastinal                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |       X  X     X        X                 X  X  X  X     X  X     X  X   |             
                                            __________________________________________________________________________|             
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Fibroma                              |                                                                      X   |             
      Leukemia Mononuclear                 |    X  X  X  X  X        X                 X  X  X  X     X  X     X  X   |             
                                            __________________________________________________________________________|             
   Thymus                                  | +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  M  M  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |       X                                   X              X               |             
 _____________________________________________________________________________________________________________________|             

                                                             Page  31                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 7| 6| 5| 7| 7| 7| 6| 7| 7| 7| 5| 7| 5| 4| 5| 6| 6| 7| 7| 6| 4| 6| 6| 7|             
                             DAY ON TEST   | 3| 3| 3| 8| 3| 3| 3| 9| 3| 3| 3| 8| 3| 3| 5| 2| 3| 7| 3| 3| 0| 3| 8| 0| 3|             
                                           | 4| 5| 1| 2| 4| 4| 4| 1| 4| 4| 4| 9| 5| 4| 3| 7| 2| 9| 4| 4| 2| 5| 0| 3| 5|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   FISCHER 344 RATS MALE                   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
    CONTROL                                | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
                                           | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM - cont               |                                                                          |             
                                           |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 INTEGUMENTARY SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Mammary Gland                           | +  +  M  +  +  +  M  M  +  +  +  M  +  +  +  M  +  +  +  +  +  M  +  M  +|             
      Fibroadenoma                         |                X              X     X                                    |             
                                            __________________________________________________________________________|             
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Basal Cell Adenoma                   |                                                       X  X               |             
      Keratoacanthoma                      |                X                                                         |             
      Sebaceous Gland, Adenoma             |                            X                                             |             
      Subcutaneous Tissue, Schwannoma      |                                                                          |             
          Malignant                        |                                                                X         |             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM                    |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Chordoma                             |                            X                                             |             
 _____________________________________________________________________________________________________________________|             
 NERVOUS SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Astrocytoma Malignant                |                                     X                                    |             
      Leukemia Mononuclear                 |       X        X                          X                              |             
 _____________________________________________________________________________________________________________________|             
 RESPIRATORY SYSTEM                        |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Alveolar/Bronchiolar Adenoma         |                                                                          |             
      Chordoma, Metastatic, Bone           |                            X                                             |             
      Leukemia Mononuclear                 |    X  X  X     X        X                 X  X  X  X     X  X     X  X   |             
                                            __________________________________________________________________________|             
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |       X                                   X                          X   |             
                                            __________________________________________________________________________|             
   Pleura                                  |                                                    +                     |             
      Mesothelioma Malignant               |                                                    X                     |             
                                            __________________________________________________________________________|             
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 SPECIAL SENSES SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Eye                                     |             +                          +                          +      |             
                                            __________________________________________________________________________|             
   Zymbal's Gland                          |                                              +                           |             
      Carcinoma                            |                                              X                           |             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |       X  X     X        X                 X  X  X  X     X  X     X  X   |             
      Renal Tubule, Adenoma                |                                                                      X   |             
                                            __________________________________________________________________________|             
   Urinary Bladder                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |       X  X                                X        X     X               |             
 _____________________________________________________________________________________________________________________|             
 SYSTEMIC LESIONS                          |                                                                          |             
                                            __________________________________________________________________________|             
   Multiple Organs                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             

                                                             Page  32                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 7| 6| 5| 7| 7| 7| 6| 7| 7| 7| 5| 7| 5| 4| 5| 6| 6| 7| 7| 6| 4| 6| 6| 7|             
                             DAY ON TEST   | 3| 3| 3| 8| 3| 3| 3| 9| 3| 3| 3| 8| 3| 3| 5| 2| 3| 7| 3| 3| 0| 3| 8| 0| 3|             
                                           | 4| 5| 1| 2| 4| 4| 4| 1| 4| 4| 4| 9| 5| 4| 3| 7| 2| 9| 4| 4| 2| 5| 0| 3| 5|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   FISCHER 344 RATS MALE                   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
    CONTROL                                | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
                                           | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 SYSTEMIC LESIONS - cont                   |                                                                          |             
                                           |                                                                          |             
      Leukemia Mononuclear                 |    X  X  X  X  X        X                 X  X  X  X     X  X     X  X   |             
      Mesothelioma Malignant               |       X                          X                 X                     |             
 _____________________________________________________________________________________________________________________|             

                                                             Page  33                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 6| 6| 6| 6| 6| 7| 7| 5| 7| 6| 6| 5| 5| 7| 6| 6| 7| 6| 5| 5| 6| 5| 5| 6| 7|            |
                             DAY ON TEST   | 6| 4| 7| 1| 4| 3| 3| 4| 3| 1| 1| 7| 6| 3| 9| 0| 2| 4| 2| 2| 1| 9| 7| 0| 3|            |
                                           | 4| 9| 3| 0| 5| 4| 4| 8| 5| 9| 0| 9| 8| 4| 2| 2| 7| 3| 6| 6| 0| 3| 6| 5| 5|            |
 _____________________________________________________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     O      |
   FISCHER 344 RATS MALE                   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     T      |
                               ANIMAL ID   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     A      |
    CONTROL                                | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|     L      |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 ALIMENTARY SYSTEM                         |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Esophagus                               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Colon                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  M  +  +|  47        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Cecum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +|  48        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Duodenum               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Jejunum                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Ileum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hepatocellular Adenoma               |                                                                          |          1 |
      Leukemia Mononuclear                 |    X  X     X  X  X  X     X  X     X  X  X  X  X  X              X     X|         30 |
                                            __________________________________________________________________________|____________|
   Mesentery                               |    +  +  +                    +  +  +  +              +  +  +  +  +  +   |  21        |
      Leukemia Mononuclear                 |                                        X                                 |          2 |
                                            __________________________________________________________________________|____________|
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |       X     X                                                            |          3 |
                                            __________________________________________________________________________|____________|
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |       X     X                             X     X                        |          6 |
                                            __________________________________________________________________________|____________|
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |       X     X                             X     X                        |          5 |
                                            __________________________________________________________________________|____________|
   Tongue                                  |       +                                                                  |   1        |
 _____________________________________________________________________________________________________________________|            |
 CARDIOVASCULAR SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |       X     X                             X  X  X                        |         10 |
 _____________________________________________________________________________________________________________________|            |
 ENDOCRINE SYSTEM                          |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |       X     X  X     X     X  X        X  X  X  X  X                     |         22 |
                                            __________________________________________________________________________|____________|
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |       X     X  X     X     X  X        X  X  X  X  X                     |         20 |
      Pheochromocytoma Complex             |                                     X                                    |          1 |
      Pheochromocytoma Benign              |                            X           X  X                              |         13 |
      Bilateral, Pheochromocytoma Benign   |                               X                                          |          1 |
                                            __________________________________________________________________________|____________|
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Adenoma                              |                                                                          |          1 |
      Adenoma, Multiple                    |                                                                          |          1 |
      Carcinoma                            |             X           X                             X                  |          3 |
                                            __________________________________________________________________________|____________|
   Parathyroid Gland                       | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
                                            __________________________________________________________________________|____________|
   Pituitary Gland                         | +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
 __________________________________________________________________________________________________________________________________ 

                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  

                                                             Page  34                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 6| 6| 6| 6| 6| 7| 7| 5| 7| 6| 6| 5| 5| 7| 6| 6| 7| 6| 5| 5| 6| 5| 5| 6| 7|            |
                             DAY ON TEST   | 6| 4| 7| 1| 4| 3| 3| 4| 3| 1| 1| 7| 6| 3| 9| 0| 2| 4| 2| 2| 1| 9| 7| 0| 3|            |
                                           | 4| 9| 3| 0| 5| 4| 4| 8| 5| 9| 0| 9| 8| 4| 2| 2| 7| 3| 6| 6| 0| 3| 6| 5| 5|            |
 _____________________________________________________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     O      |
   FISCHER 344 RATS MALE                   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     T      |
                               ANIMAL ID   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     A      |
    CONTROL                                | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|     L      |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 ENDOCRINE SYSTEM - cont                   |                                                                          |            |
                                           |                                                                          |            |
      Leukemia Mononuclear                 |       X     X        X     X              X  X  X                        |         15 |
      Pars Distalis, Adenoma               | X     X  X  X        X  X  X  X  X  X  X  X        X  X  X  X  X  X  X  X|         43 |
                                            __________________________________________________________________________|____________|
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      C-Cell, Adenoma                      |       X     X                                                            |          4 |
      C-Cell, Carcinoma                    |                                                                          |          3 |
      Follicular Cell, Carcinoma           |                                                                          |          1 |
 _____________________________________________________________________________________________________________________|            |
 GENERAL BODY SYSTEM                       |                                                                          |            |
                                           |                                                                          |            |
    None                                   |                                                                          |            |
 _____________________________________________________________________________________________________________________|            |
 GENITAL SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Epididymis                              | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Mesothelioma Malignant               |                                                                          |          2 |
                                            __________________________________________________________________________|____________|
   Penis                                   |                                  +                                       |   3        |
                                            __________________________________________________________________________|____________|
   Preputial Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Carcinoma                            |                                                                          |          2 |
      Leukemia Mononuclear                 |                                                 X                        |          2 |
      Bilateral, Carcinoma                 |                   X                                                      |          1 |
                                            __________________________________________________________________________|____________|
   Prostate                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Adenoma                              |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Seminal Vesicle                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |             X                                   X                        |          6 |
                                            __________________________________________________________________________|____________|
   Testes                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Mesothelioma Malignant               |                                                                          |          2 |
      Bilateral, Interstitial Cell, Adenoma|    X  X     X  X           X        X  X  X  X  X              X        X|         26 |
      Interstitial Cell, Adenoma           | X        X                       X                 X        X     X      |          9 |
 _____________________________________________________________________________________________________________________|            |
 HEMATOPOIETIC SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |    X  X     X  X     X     X  X     X  X  X  X  X                 X     X|         24 |
                                            __________________________________________________________________________|____________|
   Lymph Node                              |       +                       +              +  +                 +      |   8        |
      Leukemia Mononuclear                 |                               X                                          |          2 |
      Deep Cervical, Leukemia Mononuclear  |                                                                          |          1 |
      Iliac, Leukemia Mononuclear          |                                                                          |          1 |
      Pancreatic, Leukemia Mononuclear     |       X                                         X                 X      |          6 |
      Renal, Leukemia Mononuclear          |                               X              X  X                        |          5 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Bronchial                   | +  +  M  M  +  +  +  +  +  +  +  M  +  +  +  +  +  +  M  +  +  +  +  +  +|  45        |
      Leukemia Mononuclear                 |    X        X  X     X     X  X     X  X  X  X  X  X              X     X|         26 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mandibular                  | +  +  +  M  +  +  +  +  +  +  M  +  +  +  +  +  +  +  M  +  +  +  M  +  +|  46        |
 __________________________________________________________________________________________________________________________________ 

                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  

                                                             Page  35                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 6| 6| 6| 6| 6| 7| 7| 5| 7| 6| 6| 5| 5| 7| 6| 6| 7| 6| 5| 5| 6| 5| 5| 6| 7|            |
                             DAY ON TEST   | 6| 4| 7| 1| 4| 3| 3| 4| 3| 1| 1| 7| 6| 3| 9| 0| 2| 4| 2| 2| 1| 9| 7| 0| 3|            |
                                           | 4| 9| 3| 0| 5| 4| 4| 8| 5| 9| 0| 9| 8| 4| 2| 2| 7| 3| 6| 6| 0| 3| 6| 5| 5|            |
 _____________________________________________________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     O      |
   FISCHER 344 RATS MALE                   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     T      |
                               ANIMAL ID   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     A      |
    CONTROL                                | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|     L      |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 HEMATOPOIETIC SYSTEM - cont               |                                                                          |            |
                                           |                                                                          |            |
      Leukemia Mononuclear                 |    X  X     X  X           X        X  X  X  X  X  X                    X|         22 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |    X  X     X  X  X  X     X  X     X  X  X  X  X  X              X     X|         28 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mediastinal                 | +  +  +  +  +  +  +  +  +  +  +  M  +  +  M  +  +  +  +  +  +  M  +  +  +|  47        |
      Leukemia Mononuclear                 |    X  X     X  X     X     X  X     X  X     X  X  X              X     X|         26 |
                                            __________________________________________________________________________|____________|
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Fibroma                              |                                                                          |          1 |
      Leukemia Mononuclear                 |    X  X     X  X  X  X     X  X     X  X  X  X  X  X              X     X|         30 |
                                            __________________________________________________________________________|____________|
   Thymus                                  | +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +|  45        |
      Leukemia Mononuclear                 |    X                                      X     X                        |          6 |
 _____________________________________________________________________________________________________________________|            |
 INTEGUMENTARY SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Mammary Gland                           | +  +  +  M  M  +  M  M  M  M  M  +  M  +  M  +  +  +  M  M  +  M  +  +  M|  30        |
      Fibroadenoma                         |                                                                          |          3 |
                                            __________________________________________________________________________|____________|
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Basal Cell Adenoma                   |                                                                          |          2 |
      Keratoacanthoma                      |                                                 X                        |          2 |
      Sebaceous Gland, Adenoma             |                                                                          |          1 |
      Subcutaneous Tissue, Schwannoma      |                                                                          |            |
          Malignant                        |                                                                          |          1 |
 _____________________________________________________________________________________________________________________|            |
 MUSCULOSKELETAL SYSTEM                    |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Chordoma                             |                                                                          |          1 |
 _____________________________________________________________________________________________________________________|            |
 NERVOUS SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Astrocytoma Malignant                |                                                                          |          1 |
      Leukemia Mononuclear                 |       X                                                                  |          4 |
 _____________________________________________________________________________________________________________________|            |
 RESPIRATORY SYSTEM                        |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Alveolar/Bronchiolar Adenoma         |                                     X                                    |          1 |
      Chordoma, Metastatic, Bone           |                                                                          |          1 |
      Leukemia Mononuclear                 |    X  X     X  X     X     X  X     X  X  X  X  X  X              X     X|         28 |
                                            __________________________________________________________________________|____________|
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |    X  X                                   X     X                        |          7 |
                                            __________________________________________________________________________|____________|
   Pleura                                  |                                                                          |   1        |
 __________________________________________________________________________________________________________________________________ 

                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  

                                                             Page  36                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 6| 6| 6| 6| 6| 7| 7| 5| 7| 6| 6| 5| 5| 7| 6| 6| 7| 6| 5| 5| 6| 5| 5| 6| 7|            |
                             DAY ON TEST   | 6| 4| 7| 1| 4| 3| 3| 4| 3| 1| 1| 7| 6| 3| 9| 0| 2| 4| 2| 2| 1| 9| 7| 0| 3|            |
                                           | 4| 9| 3| 0| 5| 4| 4| 8| 5| 9| 0| 9| 8| 4| 2| 2| 7| 3| 6| 6| 0| 3| 6| 5| 5|            |
 _____________________________________________________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     O      |
   FISCHER 344 RATS MALE                   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     T      |
                               ANIMAL ID   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     A      |
    CONTROL                                | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|     L      |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 RESPIRATORY SYSTEM - cont                 |                                                                          |            |
                                           |                                                                          |            |
      Mesothelioma Malignant               |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 SPECIAL SENSES SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Eye                                     |                                     +  +                                 |   5        |
                                            __________________________________________________________________________|____________|
   Zymbal's Gland                          |                                                                          |   1        |
      Carcinoma                            |                                                                          |          1 |
 _____________________________________________________________________________________________________________________|            |
 URINARY SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |    X  X     X  X  X  X     X  X        X  X  X  X  X              X     X|         27 |
      Renal Tubule, Adenoma                |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Urinary Bladder                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |       X     X                                   X                        |          8 |
 __________________________________________________________________________________________________________________________________ 
 SYSTEMIC LESIONS                          |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Multiple Organs                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |    X  X     X  X  X  X     X  X     X  X  X  X  X  X              X     X|         30 |
      Mesothelioma Malignant               |                                                                          |          3 |
 __________________________________________________________________________________________________________________________________ 

                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  

                                                             Page  37                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 7| 7| 6| 5| 5| 4| 7| 7| 6| 6| 7| 6| 7| 6| 7| 7| 7| 6| 4| 7| 6| 7| 6| 6|             
                             DAY ON TEST   | 3| 3| 3| 4| 7| 5| 7| 3| 3| 7| 3| 3| 8| 3| 6| 1| 2| 0| 3| 7| 3| 2| 3| 8| 9|             
                                           | 5| 4| 5| 6| 9| 4| 5| 4| 5| 1| 8| 4| 0| 4| 3| 9| 2| 1| 2| 1| 4| 9| 4| 0| 1|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   FISCHER 344 RATS MALE                   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2|             
    0.3                                    | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
    MG/M3                                  | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 ALIMENTARY SYSTEM                         |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Esophagus                               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Colon                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Cecum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Duodenum               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Jejunum                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Ileum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                                                    X                     |             
                                            __________________________________________________________________________|             
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Carcinoma, Metastatic, Seminal       |                                                                          |             
          Vesicle                          |                                                                          |             
      Hepatocellular Carcinoma             |                                                                          |             
      Leukemia Mononuclear                 |       X     X     X        X  X  X     X  X  X  X  X  X        X        X|             
      Sarcoma, Metastatic, Uncertain       |                                                                          |             
          Primary Site                     |                                                                          |             
                                            __________________________________________________________________________|             
   Mesentery                               |    +                    +           +  +                    +        +   |             
      Carcinoma, Metastatic, Seminal       |                                                                          |             
          Vesicle                          |                                                                          |             
      Leukemia Mononuclear                 |                                                                          |             
      Sarcoma, Metastatic, Uncertain       |                                                                          |             
          Primary Site                     |                                                                          |             
                                            __________________________________________________________________________|             
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Carcinoma, Metastatic, Seminal       |                                                                          |             
          Vesicle                          |                                                                          |             
      Leukemia Mononuclear                 |             X                                         X                  |             
      Sarcoma, Metastatic, Uncertain       |                                                                          |             
          Primary Site                     |                                                                          |             
                                            __________________________________________________________________________|             
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                                                                          |             
                                            __________________________________________________________________________|             
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |             X                                                            |             
                                            __________________________________________________________________________|             
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |             X                                                            |             
 _____________________________________________________________________________________________________________________|             
 CARDIOVASCULAR SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Carcinoma, Metastatic, Seminal       |                                                                          |             
          Vesicle                          |                                                                          |             
      Leukemia Mononuclear                 |             X              X              X     X                        |             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM                          |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Carcinoma                            |                                                                          |             
      Leukemia Mononuclear                 |             X              X  X  X        X  X  X  X  X        X        X|             
 _____________________________________________________________________________________________________________________|             

                                                             Page  38                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 7| 7| 6| 5| 5| 4| 7| 7| 6| 6| 7| 6| 7| 6| 7| 7| 7| 6| 4| 7| 6| 7| 6| 6|             
                             DAY ON TEST   | 3| 3| 3| 4| 7| 5| 7| 3| 3| 7| 3| 3| 8| 3| 6| 1| 2| 0| 3| 7| 3| 2| 3| 8| 9|             
                                           | 5| 4| 5| 6| 9| 4| 5| 4| 5| 1| 8| 4| 0| 4| 3| 9| 2| 1| 2| 1| 4| 9| 4| 0| 1|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   FISCHER 344 RATS MALE                   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2|             
    0.3                                    | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
    MG/M3                                  | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM - cont                   |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |             X                 X  X        X  X  X  X  X        X        X|             
      Pheochromocytoma Malignant           |    X                                            X                        |             
      Pheochromocytoma Benign              | X  X                       X  X        X        X                 X      |             
      Bilateral, Pheochromocytoma Benign   |       X                          X           X                           |             
                                            __________________________________________________________________________|             
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Adenoma                              |                            X                             X               |             
      Adenoma, Multiple                    |                                                             X            |             
      Carcinoma                            |                                     X  X     X                       X   |             
                                            __________________________________________________________________________|             
   Parathyroid Gland                       | +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Pituitary Gland                         | +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |             X                 X           X     X  X  X                 X|             
      Pars Distalis, Adenoma               | X  X  X  X     X  X  X  X        X  X  X  X  X  X        X  X  X  X  X  X|             
                                            __________________________________________________________________________|             
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      C-Cell, Adenoma                      | X                                                                        |             
      C-Cell, Carcinoma                    |       X                                                                  |             
      Follicular Cell, Adenoma             |                                                                      X   |             
      Follicular Cell, Carcinoma           |                                              X                           |             
 _____________________________________________________________________________________________________________________|             
 GENERAL BODY SYSTEM                       |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Peritoneum                              |                                                                          |             
      Mesothelioma Malignant               |                                                                          |             
      Sarcoma, Metastatic, Uncertain       |                                                                          |             
          Primary Site                     |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 GENITAL SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Epididymis                              | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                                                                          |             
      Mesothelioma Malignant               |                                                             X            |             
                                            __________________________________________________________________________|             
   Preputial Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Carcinoma                            |                                              X     X                     |             
                                            __________________________________________________________________________|             
   Prostate                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Adenoma                              |                      X                                               X   |             
                                            __________________________________________________________________________|             
   Seminal Vesicle                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Carcinoma                            |                                                                          |             
      Leukemia Mononuclear                 |             X                                                            |             
      Sarcoma, Metastatic, Uncertain       |                                                                          |             
          Primary Site                     |                                                                          |             
                                            __________________________________________________________________________|             
   Testes                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Mesothelioma Malignant               |                                                             X            |             
      Bilateral, Interstitial Cell, Adenoma|    X  X                       X  X  X     X  X              X           X|             
      Interstitial Cell, Adenoma           | X                 X  X  X                       X     X              X   |             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM                      |                                                                          |             
                                           |                                                                          |             
 _____________________________________________________________________________________________________________________|             

                                                             Page  39                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 7| 7| 6| 5| 5| 4| 7| 7| 6| 6| 7| 6| 7| 6| 7| 7| 7| 6| 4| 7| 6| 7| 6| 6|             
                             DAY ON TEST   | 3| 3| 3| 4| 7| 5| 7| 3| 3| 7| 3| 3| 8| 3| 6| 1| 2| 0| 3| 7| 3| 2| 3| 8| 9|             
                                           | 5| 4| 5| 6| 9| 4| 5| 4| 5| 1| 8| 4| 0| 4| 3| 9| 2| 1| 2| 1| 4| 9| 4| 0| 1|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   FISCHER 344 RATS MALE                   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2|             
    0.3                                    | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
    MG/M3                                  | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM - cont               |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |             X     X        X  X  X        X  X  X  X  X        X        X|             
                                            __________________________________________________________________________|             
   Lymph Node                              |                   +           +              +  +  +                     |             
      Leukemia Mononuclear                 |                                                                          |             
      Pancreatic, Leukemia Mononuclear     |                   X           X              X  X  X                     |             
                                            __________________________________________________________________________|             
   Lymph Node, Bronchial                   | +  +  M  +  +  M  +  M  +  M  M  M  +  +  M  +  M  M  +  +  +  +  M  +  M|             
      Leukemia Mononuclear                 |             X     X                    X     X        X        X         |             
                                            __________________________________________________________________________|             
   Lymph Node, Mandibular                  | +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M|             
      Leukemia Mononuclear                 |       X     X     X        X  X  X     X  X  X  X  X  X        X         |             
                                            __________________________________________________________________________|             
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |       X     X     X        X  X  X     X  X  X  X  X  X        X         |             
                                            __________________________________________________________________________|             
   Lymph Node, Mediastinal                 | +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +|             
      Carcinoma, Metastatic, Seminal       |                                                                          |             
          Vesicle                          |                                                                          |             
      Leukemia Mononuclear                 |       X     X     X        X  X  X     X  X  X  X  X  X        X         |             
                                            __________________________________________________________________________|             
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Carcinoma, Metastatic, Seminal       |                                                                          |             
          Vesicle                          |                                                                          |             
      Leukemia Mononuclear                 |       X     X     X        X  X  X     X  X  X  X  X  X        X        X|             
      Sarcoma, Metastatic, Uncertain       |                                                                          |             
          Primary Site                     |                                                                          |             
                                            __________________________________________________________________________|             
   Thymus                                  | +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  M  +  +  +  +  +  +  +  M  +|             
      Leukemia Mononuclear                 |             X                             X     X     X                  |             
 _____________________________________________________________________________________________________________________|             
 INTEGUMENTARY SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Mammary Gland                           | +  +  +  M  M  +  M  +  +  +  +  +  +  +  M  +  +  M  M  M  M  +  M  +  M|             
      Fibroadenoma                         |                                                                          |             
                                            __________________________________________________________________________|             
   Skin                                    | +  +  +  +  I  +  +  +  +  +  +  +  +  +  I  +  +  +  +  +  +  +  +  +  +|             
      Keratoacanthoma                      |                         X           X                 X                  |             
      Sarcoma, Metastatic, Uncertain       |                                                                          |             
          Primary Site                     |                                                                          |             
      Sebaceous Gland, Adenoma             |                                     X                                    |             
      Subcutaneous Tissue, Fibroma         |                                                 X                        |             
      Subcutaneous Tissue, Fibrosarcoma    | X        X                                                               |             
      Subcutaneous Tissue, Lipoma          |                                        X                                 |             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM                    |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Chordoma                             |                                                                          |             
      Osteosarcoma                         |                                     X                                    |             
                                            __________________________________________________________________________|             
   Skeletal Muscle                         |                                                                          |             
      Carcinoma, Metastatic, Seminal       |                                                                          |             
          Vesicle                          |                                                                          |             
      Sarcoma, Metastatic, Uncertain       |                                                                          |             
 _____________________________________________________________________________________________________________________|             

                                                             Page  40                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 7| 7| 6| 5| 5| 4| 7| 7| 6| 6| 7| 6| 7| 6| 7| 7| 7| 6| 4| 7| 6| 7| 6| 6|             
                             DAY ON TEST   | 3| 3| 3| 4| 7| 5| 7| 3| 3| 7| 3| 3| 8| 3| 6| 1| 2| 0| 3| 7| 3| 2| 3| 8| 9|             
                                           | 5| 4| 5| 6| 9| 4| 5| 4| 5| 1| 8| 4| 0| 4| 3| 9| 2| 1| 2| 1| 4| 9| 4| 0| 1|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   FISCHER 344 RATS MALE                   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2|             
    0.3                                    | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
    MG/M3                                  | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM - cont             |                                                                          |             
                                           |                                                                          |             
          Primary Site                     |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 NERVOUS SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                                                 X     X                  |             
 _____________________________________________________________________________________________________________________|             
 RESPIRATORY SYSTEM                        |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Alveolar/Bronchiolar Adenoma         |                         X              X                                 |             
      Carcinoma, Metastatic, Seminal       |                                                                          |             
          Vesicle                          |                                                                          |             
      Leukemia Mononuclear                 |       X     X     X        X  X  X     X  X  X  X  X  X        X        X|             
      Osteosarcoma, Metastatic, Bone       |                                                                          |             
                                            __________________________________________________________________________|             
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |             X                 X  X        X  X  X     X                  |             
                                            __________________________________________________________________________|             
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 SPECIAL SENSES SYSTEM                     |                                                                          |             
                                           |                                                                          |             
    None                                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |             X     X        X  X  X        X  X  X  X  X        X        X|             
      Sarcoma, Metastatic, Uncertain       |                                                                          |             
          Primary Site                     |                                                                          |             
                                            __________________________________________________________________________|             
   Urinary Bladder                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |             X                                                            |             
 _____________________________________________________________________________________________________________________|             
 SYSTEMIC LESIONS                          |                                                                          |             
                                            __________________________________________________________________________|             
   Multiple Organs                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |       X     X     X        X  X  X     X  X  X  X  X  X        X        X|             
      Mesothelioma Malignant               |                                                             X            |             
 _____________________________________________________________________________________________________________________|             

                                                             Page  41                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 6| 5| 6| 5| 6| 6| 6| 4| 7| 7| 6| 5| 7| 6| 6| 7| 6| 7| 7| 6| 4| 6| 6| 5| 6|            |
                             DAY ON TEST   | 2| 8| 9| 7| 1| 7| 4| 0| 3| 3| 0| 4| 3| 3| 3| 3| 8| 3| 3| 5| 9| 3| 6| 8| 4|            |
                                           | 9| 9| 4| 6| 0| 8| 9| 8| 5| 4| 0| 1| 4| 1| 1| 5| 1| 4| 4| 2| 5| 8| 9| 9| 5|            |
 _____________________________________________________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     O      |
   FISCHER 344 RATS MALE                   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     T      |
                               ANIMAL ID   | 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2|     A      |
    0.3                                    | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|     L      |
    MG/M3                                  | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 ALIMENTARY SYSTEM                         |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Esophagus                               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Colon                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Cecum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Duodenum               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Jejunum                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Ileum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|  49        |
      Leukemia Mononuclear                 |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Carcinoma, Metastatic, Seminal       |                                                                          |            |
          Vesicle                          |                      X                                                   |          1 |
      Hepatocellular Carcinoma             |                                           X                              |          1 |
      Leukemia Mononuclear                 | X  X  X  X        X     X  X  X        X  X  X  X  X  X  X     X  X     X|         32 |
      Sarcoma, Metastatic, Uncertain       |                                                                          |            |
          Primary Site                     |                                  X                                       |          1 |
                                            __________________________________________________________________________|____________|
   Mesentery                               | +  +                 +           +  +  +           +              +      |  14        |
      Carcinoma, Metastatic, Seminal       |                                                                          |            |
          Vesicle                          |                      X                                                   |          1 |
      Leukemia Mononuclear                 |                                                                   X      |          1 |
      Sarcoma, Metastatic, Uncertain       |                                                                          |            |
          Primary Site                     |                                  X                                       |          1 |
                                            __________________________________________________________________________|____________|
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Carcinoma, Metastatic, Seminal       |                                                                          |            |
          Vesicle                          |                      X                                                   |          1 |
      Leukemia Mononuclear                 |    X                                                           X        X|          5 |
      Sarcoma, Metastatic, Uncertain       |                                                                          |            |
          Primary Site                     |                                  X                                       |          1 |
                                            __________________________________________________________________________|____________|
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |                                                                   X      |          1 |
                                            __________________________________________________________________________|____________|
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |                                                          X              X|          3 |
                                            __________________________________________________________________________|____________|
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |                                                          X              X|          3 |
 _____________________________________________________________________________________________________________________|            |
 CARDIOVASCULAR SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Carcinoma, Metastatic, Seminal       |                                                                          |            |
          Vesicle                          |                      X                                                   |          1 |
      Leukemia Mononuclear                 |    X  X                 X     X           X              X              X|         11 |
 __________________________________________________________________________________________________________________________________ 

                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  

                                                             Page  42                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 6| 5| 6| 5| 6| 6| 6| 4| 7| 7| 6| 5| 7| 6| 6| 7| 6| 7| 7| 6| 4| 6| 6| 5| 6|            |
                             DAY ON TEST   | 2| 8| 9| 7| 1| 7| 4| 0| 3| 3| 0| 4| 3| 3| 3| 3| 8| 3| 3| 5| 9| 3| 6| 8| 4|            |
                                           | 9| 9| 4| 6| 0| 8| 9| 8| 5| 4| 0| 1| 4| 1| 1| 5| 1| 4| 4| 2| 5| 8| 9| 9| 5|            |
 _____________________________________________________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     O      |
   FISCHER 344 RATS MALE                   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     T      |
                               ANIMAL ID   | 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2|     A      |
    0.3                                    | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|     L      |
    MG/M3                                  | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 CARDIOVASCULAR SYSTEM - cont              |                                                                          |            |
                                           |                                                                          |            |
 _____________________________________________________________________________________________________________________|            |
 ENDOCRINE SYSTEM                          |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Carcinoma                            |                   X                                                      |          1 |
      Leukemia Mononuclear                 |    X  X  X        X     X     X        X  X                       X     X|         21 |
                                            __________________________________________________________________________|____________|
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |    X     X        X     X     X        X  X                       X     X|         19 |
      Pheochromocytoma Malignant           |                                                                          |          2 |
      Pheochromocytoma Benign              |    X  X                          X  X     X  X  X        X               |         15 |
      Bilateral, Pheochromocytoma Benign   |                                                                X         |          4 |
                                            __________________________________________________________________________|____________|
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Adenoma                              |                   X                 X                                    |          4 |
      Adenoma, Multiple                    |                                                                          |          1 |
      Carcinoma                            |                                                                          |          4 |
                                            __________________________________________________________________________|____________|
   Parathyroid Gland                       | +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
                                            __________________________________________________________________________|____________|
   Pituitary Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Leukemia Mononuclear                 | X  X  X  X        X     X     X        X  X              X              X|         18 |
      Pars Distalis, Adenoma               |    X  X  X  X  X  X     X  X  X  X  X  X  X  X  X  X  X  X  X        X   |         40 |
                                            __________________________________________________________________________|____________|
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      C-Cell, Adenoma                      |                                              X                           |          2 |
      C-Cell, Carcinoma                    |       X  X                                                               |          3 |
      Follicular Cell, Adenoma             |                                                                          |          1 |
      Follicular Cell, Carcinoma           |                                     X                                    |          2 |
 _____________________________________________________________________________________________________________________|            |
 GENERAL BODY SYSTEM                       |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Peritoneum                              |                                  +              +                        |   2        |
      Mesothelioma Malignant               |                                                 X                        |          1 |
      Sarcoma, Metastatic, Uncertain       |                                                                          |            |
          Primary Site                     |                                  X                                       |          1 |
 _____________________________________________________________________________________________________________________|            |
 GENITAL SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Epididymis                              | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |                         X                                                |          1 |
      Mesothelioma Malignant               |                                                 X                        |          2 |
                                            __________________________________________________________________________|____________|
   Preputial Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Carcinoma                            |                                                                          |          2 |
                                            __________________________________________________________________________|____________|
   Prostate                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Adenoma                              |                                                                          |          2 |
                                            __________________________________________________________________________|____________|
   Seminal Vesicle                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 __________________________________________________________________________________________________________________________________ 

                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  

                                                             Page  43                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 6| 5| 6| 5| 6| 6| 6| 4| 7| 7| 6| 5| 7| 6| 6| 7| 6| 7| 7| 6| 4| 6| 6| 5| 6|            |
                             DAY ON TEST   | 2| 8| 9| 7| 1| 7| 4| 0| 3| 3| 0| 4| 3| 3| 3| 3| 8| 3| 3| 5| 9| 3| 6| 8| 4|            |
                                           | 9| 9| 4| 6| 0| 8| 9| 8| 5| 4| 0| 1| 4| 1| 1| 5| 1| 4| 4| 2| 5| 8| 9| 9| 5|            |
 _____________________________________________________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     O      |
   FISCHER 344 RATS MALE                   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     T      |
                               ANIMAL ID   | 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2|     A      |
    0.3                                    | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|     L      |
    MG/M3                                  | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 GENITAL SYSTEM - cont                     |                                                                          |            |
                                           |                                                                          |            |
      Carcinoma                            |                      X                                                   |          1 |
      Leukemia Mononuclear                 |                         X                                               X|          3 |
      Sarcoma, Metastatic, Uncertain       |                                                                          |            |
          Primary Site                     |                                  X                                       |          1 |
                                            __________________________________________________________________________|____________|
   Testes                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Mesothelioma Malignant               |                                                 X                        |          2 |
      Bilateral, Interstitial Cell, Adenoma|    X              X        X        X  X  X        X           X  X      |         18 |
      Interstitial Cell, Adenoma           | X     X                                      X  X     X  X               |         13 |
 _____________________________________________________________________________________________________________________|            |
 HEMATOPOIETIC SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 | X  X     X        X     X     X        X  X              X     X  X     X|         24 |
                                            __________________________________________________________________________|____________|
   Lymph Node                              |    +              +                                      +              +|   9        |
      Leukemia Mononuclear                 |                                                                         X|          1 |
      Pancreatic, Leukemia Mononuclear     |    X              X                                      X              X|          9 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Bronchial                   | +  M  M  +  M  +  M  M  M  +  +  M  M  +  +  +  +  M  +  +  +  +  +  +  +|  30        |
      Leukemia Mononuclear                 | X        X                    X        X  X           X  X        X     X|         15 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mandibular                  | +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  47        |
      Leukemia Mononuclear                 | X  X  X                 X     X        X  X           X  X     X  X     X|         25 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 | X  X  X  X        X     X  X  X        X  X        X  X  X     X  X     X|         29 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mediastinal                 | +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +|  46        |
      Carcinoma, Metastatic, Seminal       |                                                                          |            |
          Vesicle                          |                      X                                                   |          1 |
      Leukemia Mononuclear                 | X  X  X  X        X     X     X        X  X        X  X  X        X     X|         27 |
                                            __________________________________________________________________________|____________|
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Carcinoma, Metastatic, Seminal       |                                                                          |            |
          Vesicle                          |                      X                                                   |          1 |
      Leukemia Mononuclear                 | X  X  X  X        X     X  X  X        X  X  X  X  X  X  X     X  X     X|         32 |
      Sarcoma, Metastatic, Uncertain       |                                                                          |            |
          Primary Site                     |                                  X                                       |          1 |
                                            __________________________________________________________________________|____________|
   Thymus                                  | +  +  +  +  +  M  +  +  M  +  +  +  +  M  +  M  +  +  M  +  +  +  +  +  +|  42        |
      Leukemia Mononuclear                 |    X  X                                                        X        X|          8 |
 _____________________________________________________________________________________________________________________|            |
 INTEGUMENTARY SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Mammary Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  M  M  M  M  +  +  +  +  M  +  M  +|  34        |
      Fibroadenoma                         |                            X                                             |          1 |
                                            __________________________________________________________________________|____________|
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
      Keratoacanthoma                      |    X                                      X                              |          5 |
 __________________________________________________________________________________________________________________________________ 

                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  

                                                             Page  44                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 6| 5| 6| 5| 6| 6| 6| 4| 7| 7| 6| 5| 7| 6| 6| 7| 6| 7| 7| 6| 4| 6| 6| 5| 6|            |
                             DAY ON TEST   | 2| 8| 9| 7| 1| 7| 4| 0| 3| 3| 0| 4| 3| 3| 3| 3| 8| 3| 3| 5| 9| 3| 6| 8| 4|            |
                                           | 9| 9| 4| 6| 0| 8| 9| 8| 5| 4| 0| 1| 4| 1| 1| 5| 1| 4| 4| 2| 5| 8| 9| 9| 5|            |
 _____________________________________________________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     O      |
   FISCHER 344 RATS MALE                   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     T      |
                               ANIMAL ID   | 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2|     A      |
    0.3                                    | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|     L      |
    MG/M3                                  | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 INTEGUMENTARY SYSTEM - cont               |                                                                          |            |
                                           |                                                                          |            |
      Sarcoma, Metastatic, Uncertain       |                                                                          |            |
          Primary Site                     |                                  X                                       |          1 |
      Sebaceous Gland, Adenoma             |                                                                          |          1 |
      Subcutaneous Tissue, Fibroma         |                                                                          |          1 |
      Subcutaneous Tissue, Fibrosarcoma    |                                                                          |          2 |
      Subcutaneous Tissue, Lipoma          |                                                                          |          1 |
 _____________________________________________________________________________________________________________________|            |
 MUSCULOSKELETAL SYSTEM                    |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Chordoma                             |                                                                      X   |          1 |
      Osteosarcoma                         |                                           X     X                        |          3 |
                                            __________________________________________________________________________|____________|
   Skeletal Muscle                         |                      +           +                                       |   2        |
      Carcinoma, Metastatic, Seminal       |                                                                          |            |
          Vesicle                          |                      X                                                   |          1 |
      Sarcoma, Metastatic, Uncertain       |                                                                          |            |
          Primary Site                     |                                  X                                       |          1 |
 _____________________________________________________________________________________________________________________|            |
 NERVOUS SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |                                                                   X     X|          4 |
 _____________________________________________________________________________________________________________________|            |
 RESPIRATORY SYSTEM                        |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Alveolar/Bronchiolar Adenoma         |                                           X                          X   |          4 |
      Carcinoma, Metastatic, Seminal       |                                                                          |            |
          Vesicle                          |                      X                                                   |          1 |
      Leukemia Mononuclear                 | X  X  X  X        X     X  X  X        X  X  X  X  X  X  X     X  X     X|         32 |
      Osteosarcoma, Metastatic, Bone       |                                           X                              |          1 |
                                            __________________________________________________________________________|____________|
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |    X     X        X           X        X  X                       X     X|         15 |
                                            __________________________________________________________________________|____________|
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 SPECIAL SENSES SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
    None                                   |                                                                          |            |
 _____________________________________________________________________________________________________________________|            |
 URINARY SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 | X  X  X  X        X     X     X        X  X        X  X  X     X  X     X|         27 |
 __________________________________________________________________________________________________________________________________ 

                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  

                                                             Page  45                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 6| 5| 6| 5| 6| 6| 6| 4| 7| 7| 6| 5| 7| 6| 6| 7| 6| 7| 7| 6| 4| 6| 6| 5| 6|            |
                             DAY ON TEST   | 2| 8| 9| 7| 1| 7| 4| 0| 3| 3| 0| 4| 3| 3| 3| 3| 8| 3| 3| 5| 9| 3| 6| 8| 4|            |
                                           | 9| 9| 4| 6| 0| 8| 9| 8| 5| 4| 0| 1| 4| 1| 1| 5| 1| 4| 4| 2| 5| 8| 9| 9| 5|            |
 _____________________________________________________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     O      |
   FISCHER 344 RATS MALE                   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     T      |
                               ANIMAL ID   | 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2|     A      |
    0.3                                    | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|     L      |
    MG/M3                                  | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 URINARY SYSTEM - cont                     |                                                                          |            |
                                           |                                                                          |            |
      Sarcoma, Metastatic, Uncertain       |                                                                          |            |
          Primary Site                     |                                  X                                       |          1 |
                                            __________________________________________________________________________|____________|
   Urinary Bladder                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |                         X              X                 X              X|          5 |
 __________________________________________________________________________________________________________________________________ 
 SYSTEMIC LESIONS                          |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Multiple Organs                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 | X  X  X  X        X     X  X  X        X  X  X  X  X  X  X     X  X     X|         32 |
      Mesothelioma Malignant               |                                                 X                        |          2 |
 __________________________________________________________________________________________________________________________________ 

                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  

                                                             Page  46                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 5| 7| 5| 7| 7| 4| 6| 7| 6| 7| 6| 5| 6| 7| 7| 7| 6| 7| 7| 2| 5| 5| 7| 6| 6|             
                             DAY ON TEST   | 8| 3| 8| 3| 1| 3| 9| 3| 1| 3| 5| 3| 5| 3| 3| 3| 5| 0| 3| 7| 0| 2| 3| 7| 7|             
                                           | 2| 4| 1| 4| 3| 5| 4| 4| 1| 4| 2| 4| 7| 4| 4| 5| 4| 9| 4| 2| 9| 6| 5| 8| 3|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   FISCHER 344 RATS MALE                   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4|             
    1.0                                    | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
    MG/M3                                  | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 ALIMENTARY SYSTEM                         |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Esophagus                               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Colon                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |             X                                                        X   |             
      Mesothelioma Malignant               |                                                                          |             
                                            __________________________________________________________________________|             
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Cecum                  | +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |             X                                                        X   |             
      Mesothelioma Malignant               |                                                                          |             
                                            __________________________________________________________________________|             
   Intestine Small, Duodenum               | +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |             X                                                        X   |             
      Mesothelioma Malignant               |                                                                          |             
                                            __________________________________________________________________________|             
   Intestine Small, Jejunum                | +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +|             
      Leukemia Mononuclear                 |             X                                                        X   |             
                                            __________________________________________________________________________|             
   Intestine Small, Ileum                  | +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +|             
      Leukemia Mononuclear                 |             X                                                        X   |             
                                            __________________________________________________________________________|             
   Liver                                   | +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hepatocellular Adenoma               |                                                                X         |             
      Leukemia Mononuclear                 |             X  X     X  X        X           X  X  X  X     X     X  X  X|             
      Mesothelioma Malignant               |                                                                          |             
                                            __________________________________________________________________________|             
   Mesentery                               |    +  +           +                 +        +                          +|             
      Fat, Lipoma                          |                   X                                                      |             
                                            __________________________________________________________________________|             
   Pancreas                                | +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Adenoma                              |                                                                      X   |             
      Carcinoma                            |                      X                                                   |             
      Leukemia Mononuclear                 |             X                                                        X   |             
      Mesothelioma Malignant               |                                                                          |             
                                            __________________________________________________________________________|             
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                                                                          |             
                                            __________________________________________________________________________|             
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |             X                                                            |             
      Mesothelioma Malignant               |                                                                          |             
                                            __________________________________________________________________________|             
   Stomach, Glandular                      | +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |             X                                                        X   |             
                                            __________________________________________________________________________|             
   Tooth                                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 CARDIOVASCULAR SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                X                 X                                       |             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM                          |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Adrenal Cortex                          | +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Adenoma                              |                                                 X                        |             
      Carcinoma                            |                                                                          |             
      Leukemia Mononuclear                 |             X  X     X                             X                 X   |             
 _____________________________________________________________________________________________________________________|             

                                                             Page  47                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 5| 7| 5| 7| 7| 4| 6| 7| 6| 7| 6| 5| 6| 7| 7| 7| 6| 7| 7| 2| 5| 5| 7| 6| 6|             
                             DAY ON TEST   | 8| 3| 8| 3| 1| 3| 9| 3| 1| 3| 5| 3| 5| 3| 3| 3| 5| 0| 3| 7| 0| 2| 3| 7| 7|             
                                           | 2| 4| 1| 4| 3| 5| 4| 4| 1| 4| 2| 4| 7| 4| 4| 5| 4| 9| 4| 2| 9| 6| 5| 8| 3|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   FISCHER 344 RATS MALE                   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4|             
    1.0                                    | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
    MG/M3                                  | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM - cont                   |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                X                                   X                     |             
      Pheochromocytoma Malignant           |                      X                                                  X|             
      Pheochromocytoma Complex             |                                                                          |             
      Pheochromocytoma Benign              |    X  X              X              X        X                           |             
      Bilateral, Pheochromocytoma Benign   |                                        X                       X         |             
                                            __________________________________________________________________________|             
   Islets, Pancreatic                      | +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Adenoma                              |                                              X        X     X            |             
      Carcinoma                            |                                     X                                X   |             
                                            __________________________________________________________________________|             
   Parathyroid Gland                       | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Pituitary Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |             X  X                                   X  X                  |             
      Pars Distalis, Adenoma               | X  X  X     X     X  X  X  X  X  X  X  X  X  X  X  X  X     X        X  X|             
                                            __________________________________________________________________________|             
   Thyroid Gland                           | +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                                                                          |             
      C-Cell, Adenoma                      |                            X                                             |             
      C-Cell, Carcinoma                    | X           X                                                            |             
 _____________________________________________________________________________________________________________________|             
 GENERAL BODY SYSTEM                       |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Peritoneum                              |                                                                          |             
      Mesothelioma Malignant               |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 GENITAL SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Epididymis                              | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                                                                          |             
      Mesothelioma Malignant               |                                                                          |             
                                            __________________________________________________________________________|             
   Preputial Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Adenoma                              |                                                 X                        |             
      Bilateral, Adenoma                   |                   X                                                      |             
                                            __________________________________________________________________________|             
   Prostate                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Adenoma                              |                                                       X                  |             
      Leukemia Mononuclear                 |             X                                                            |             
      Mesothelioma Malignant               |                                                                          |             
                                            __________________________________________________________________________|             
   Seminal Vesicle                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |             X                                                        X   |             
      Mesothelioma Malignant               |                                                                          |             
                                            __________________________________________________________________________|             
   Testes                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Mesothelioma Malignant               |                                                                          |             
      Bilateral, Interstitial Cell, Adenoma|          X        X     X              X  X     X     X           X  X  X|             
      Interstitial Cell, Adenoma           |    X        X                 X  X           X                           |             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone Marrow                             | +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |             X  X                 X                 X        X            |             
 _____________________________________________________________________________________________________________________|             

                                                             Page  48                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 5| 7| 5| 7| 7| 4| 6| 7| 6| 7| 6| 5| 6| 7| 7| 7| 6| 7| 7| 2| 5| 5| 7| 6| 6|             
                             DAY ON TEST   | 8| 3| 8| 3| 1| 3| 9| 3| 1| 3| 5| 3| 5| 3| 3| 3| 5| 0| 3| 7| 0| 2| 3| 7| 7|             
                                           | 2| 4| 1| 4| 3| 5| 4| 4| 1| 4| 2| 4| 7| 4| 4| 5| 4| 9| 4| 2| 9| 6| 5| 8| 3|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   FISCHER 344 RATS MALE                   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4|             
    1.0                                    | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
    MG/M3                                  | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM - cont               |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Lymph Node                              |             +                    +                 +                 +   |             
      Leukemia Mononuclear                 |                                                                          |             
      Iliac, Leukemia Mononuclear          |                                                                          |             
      Pancreatic, Leukemia Mononuclear     |             X                    X                 X                 X   |             
      Renal, Leukemia Mononuclear          |                                                                      X   |             
                                            __________________________________________________________________________|             
   Lymph Node, Bronchial                   | +  +  +  +  +  +  M  +  +  M  +  +  M  +  +  +  M  +  M  M  +  +  +  +  +|             
      Leukemia Mononuclear                 |             X  X     X                             X        X            |             
                                            __________________________________________________________________________|             
   Lymph Node, Mandibular                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  M|             
      Leukemia Mononuclear                 |       X     X  X     X           X                 X  X     X            |             
                                            __________________________________________________________________________|             
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |       X     X  X     X           X                 X  X     X     X  X   |             
                                            __________________________________________________________________________|             
   Lymph Node, Mediastinal                 | +  +  A  +  +  +  M  +  +  +  +  +  M  +  +  +  +  +  +  +  +  M  +  +  +|             
      Leukemia Mononuclear                 |             X  X     X           X              X  X  X     X        X   |             
                                            __________________________________________________________________________|             
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |       X     X  X     X  X        X           X  X  X  X     X     X  X  X|             
      Mesothelioma Malignant               |                                                                          |             
                                            __________________________________________________________________________|             
   Thymus                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +|             
      Leukemia Mononuclear                 |             X  X                                   X  X                  |             
      Thymoma Benign                       |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 INTEGUMENTARY SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Mammary Gland                           | +  M  M  +  M  +  +  +  M  M  +  M  +  +  +  +  +  +  +  +  +  +  +  +  M|             
      Fibroadenoma                         |                               X                                   X      |             
                                            __________________________________________________________________________|             
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Subcutaneous Tissue, Fibroma         |                                                                          |             
      Subcutaneous Tissue, Fibrosarcoma    |                                                                          |             
      Subcutaneous Tissue, Lipoma          |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM                    |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Skeletal Muscle                         |                                                                      +   |             
      Leukemia Mononuclear                 |                                                                      X   |             
 _____________________________________________________________________________________________________________________|             
 NERVOUS SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Astrocytoma Malignant                |                                                          X               |             
      Leukemia Mononuclear                 |             X  X                                                         |             
                                            __________________________________________________________________________|             
   Spinal Cord                             |                +                                                         |             
      Leukemia Mononuclear                 |                X                                                         |             
 _____________________________________________________________________________________________________________________|             
 RESPIRATORY SYSTEM                        |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Larynx                                  | +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  I  +  +  +  +  +|             
      Leukemia Mononuclear                 |             X                                                            |             
                                            __________________________________________________________________________|             
   Lung                                    | +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             

                                                             Page  49                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 5| 7| 5| 7| 7| 4| 6| 7| 6| 7| 6| 5| 6| 7| 7| 7| 6| 7| 7| 2| 5| 5| 7| 6| 6|             
                             DAY ON TEST   | 8| 3| 8| 3| 1| 3| 9| 3| 1| 3| 5| 3| 5| 3| 3| 3| 5| 0| 3| 7| 0| 2| 3| 7| 7|             
                                           | 2| 4| 1| 4| 3| 5| 4| 4| 1| 4| 2| 4| 7| 4| 4| 5| 4| 9| 4| 2| 9| 6| 5| 8| 3|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   FISCHER 344 RATS MALE                   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4|             
    1.0                                    | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
    MG/M3                                  | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 RESPIRATORY SYSTEM - cont                 |                                                                          |             
                                           |                                                                          |             
      Alveolar/Bronchiolar Adenoma         |                         X                                                |             
      Alveolar/Bronchiolar Carcinoma       |                               X                                          |             
      Leukemia Mononuclear                 |             X  X     X           X           X  X  X  X     X        X  X|             
                                            __________________________________________________________________________|             
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |             X  X                                   X                     |             
                                            __________________________________________________________________________|             
   Trachea                                 | +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 SPECIAL SENSES SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Eye                                     |                                                       +                  |             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Kidney                                  | +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |             X  X     X                       X  X  X  X     X        X   |             
      Mesothelioma Malignant               |                                                                          |             
      Renal Tubule, Adenoma                |                   X                                                      |             
                                            __________________________________________________________________________|             
   Urinary Bladder                         | +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |             X  X                                      X              X   |             
      Mesothelioma Malignant               |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 SYSTEMIC LESIONS                          |                                                                          |             
                                            __________________________________________________________________________|             
   Multiple Organs                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |       X     X  X     X  X        X           X  X  X  X     X     X  X  X|             
      Mesothelioma Malignant               |                                                                          |             
 _____________________________________________________________________________________________________________________|             

                                                             Page  50                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 6| 7| 7| 7| 7| 7| 6| 6| 7| 7| 6| 4| 6| 6| 6| 7| 7| 5| 7| 6| 7| 6| 7| 6|            |
                             DAY ON TEST   | 3| 7| 3| 3| 3| 3| 2| 3| 8| 3| 3| 3| 6| 7| 9| 4| 3| 3| 1| 3| 1| 3| 3| 3| 4|            |
                                           | 4| 3| 5| 4| 4| 4| 9| 2| 1| 4| 4| 1| 7| 1| 9| 2| 4| 4| 8| 4| 1| 5| 0| 4| 9|            |
 _____________________________________________________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     O      |
   FISCHER 344 RATS MALE                   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     T      |
                               ANIMAL ID   | 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4|     A      |
    1.0                                    | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|     L      |
    MG/M3                                  | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 ALIMENTARY SYSTEM                         |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Esophagus                               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Colon                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +|  49        |
      Leukemia Mononuclear                 |                                                                          |          2 |
      Mesothelioma Malignant               |                                                                         X|          1 |
                                            __________________________________________________________________________|____________|
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Cecum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +|  48        |
      Leukemia Mononuclear                 |                                                                          |          2 |
      Mesothelioma Malignant               |                                                                         X|          1 |
                                            __________________________________________________________________________|____________|
   Intestine Small, Duodenum               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +|  48        |
      Leukemia Mononuclear                 |                                                                          |          2 |
      Mesothelioma Malignant               |                                                                         X|          1 |
                                            __________________________________________________________________________|____________|
   Intestine Small, Jejunum                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +|  47        |
      Leukemia Mononuclear                 |                                                                          |          2 |
                                            __________________________________________________________________________|____________|
   Intestine Small, Ileum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +|  47        |
      Leukemia Mononuclear                 |                                                                          |          2 |
                                            __________________________________________________________________________|____________|
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +|  48        |
      Hepatocellular Adenoma               |                                                                          |          1 |
      Leukemia Mononuclear                 | X  X           X  X     X  X  X  X     X     X  X        X  X  X     X   |         28 |
      Mesothelioma Malignant               |                                                                         X|          1 |
                                            __________________________________________________________________________|____________|
   Mesentery                               |                            +  +  +        +           +                  |  11        |
      Fat, Lipoma                          |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +|  48        |
      Adenoma                              |                                                                          |          1 |
      Carcinoma                            |                                                                          |          1 |
      Leukemia Mononuclear                 |                X                                                         |          3 |
      Mesothelioma Malignant               |                                                                         X|          1 |
                                            __________________________________________________________________________|____________|
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |                X                                                         |          1 |
                                            __________________________________________________________________________|____________|
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +|  49        |
      Leukemia Mononuclear                 |                X                             X                           |          3 |
      Mesothelioma Malignant               |                                                                         X|          1 |
                                            __________________________________________________________________________|____________|
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +|  48        |
      Leukemia Mononuclear                 |                                              X                           |          3 |
                                            __________________________________________________________________________|____________|
   Tooth                                   |                            +                                             |   1        |
 _____________________________________________________________________________________________________________________|            |
 CARDIOVASCULAR SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |                X                                                         |          3 |
 _____________________________________________________________________________________________________________________|            |
 ENDOCRINE SYSTEM                          |                                                                          |            |
 __________________________________________________________________________________________________________________________________ 

                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  

                                                             Page  51                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 6| 7| 7| 7| 7| 7| 6| 6| 7| 7| 6| 4| 6| 6| 6| 7| 7| 5| 7| 6| 7| 6| 7| 6|            |
                             DAY ON TEST   | 3| 7| 3| 3| 3| 3| 2| 3| 8| 3| 3| 3| 6| 7| 9| 4| 3| 3| 1| 3| 1| 3| 3| 3| 4|            |
                                           | 4| 3| 5| 4| 4| 4| 9| 2| 1| 4| 4| 1| 7| 1| 9| 2| 4| 4| 8| 4| 1| 5| 0| 4| 9|            |
 _____________________________________________________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     O      |
   FISCHER 344 RATS MALE                   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     T      |
                               ANIMAL ID   | 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4|     A      |
    1.0                                    | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|     L      |
    MG/M3                                  | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 ENDOCRINE SYSTEM - cont                   |                                                                          |            |
                                           |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +|  48        |
      Adenoma                              |                                                                          |          1 |
      Carcinoma                            |                                        X                                 |          1 |
      Leukemia Mononuclear                 |    X           X        X  X                 X              X            |         11 |
                                            __________________________________________________________________________|____________|
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +|  49        |
      Leukemia Mononuclear                 |                X        X  X                 X              X            |          7 |
      Pheochromocytoma Malignant           |                                                                          |          2 |
      Pheochromocytoma Complex             |                   X                                                      |          1 |
      Pheochromocytoma Benign              |    X  X              X  X  X  X        X  X  X     X     X           X   |         17 |
      Bilateral, Pheochromocytoma Benign   | X        X                                                     X  X      |          6 |
                                            __________________________________________________________________________|____________|
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +|  48        |
      Adenoma                              |                                                    X              X      |          5 |
      Carcinoma                            | X                       X                                                |          4 |
                                            __________________________________________________________________________|____________|
   Parathyroid Gland                       | +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Pituitary Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |                X  X                                         X            |          7 |
      Pars Distalis, Adenoma               | X  X     X  X     X  X  X  X  X  X  X  X  X  X     X  X  X  X  X  X  X  X|         42 |
                                            __________________________________________________________________________|____________|
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +|  48        |
      Leukemia Mononuclear                 |                X                                                         |          1 |
      C-Cell, Adenoma                      |             X                                                           X|          3 |
      C-Cell, Carcinoma                    |                                                          X              X|          4 |
 _____________________________________________________________________________________________________________________|            |
 GENERAL BODY SYSTEM                       |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Peritoneum                              |                                                                         +|   1        |
      Mesothelioma Malignant               |                                                                         X|          1 |
 _____________________________________________________________________________________________________________________|            |
 GENITAL SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Epididymis                              | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |                X                                                         |          1 |
      Mesothelioma Malignant               |                                                                         X|          1 |
                                            __________________________________________________________________________|____________|
   Preputial Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +|  49        |
      Adenoma                              |                                                                          |          1 |
      Bilateral, Adenoma                   |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Prostate                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +|  49        |
      Adenoma                              |    X        X                 X                                          |          4 |
      Leukemia Mononuclear                 |                                                                          |          1 |
      Mesothelioma Malignant               |                                                                         X|          1 |
                                            __________________________________________________________________________|____________|
   Seminal Vesicle                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +|  49        |
 __________________________________________________________________________________________________________________________________ 

                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  

                                                             Page  52                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 6| 7| 7| 7| 7| 7| 6| 6| 7| 7| 6| 4| 6| 6| 6| 7| 7| 5| 7| 6| 7| 6| 7| 6|            |
                             DAY ON TEST   | 3| 7| 3| 3| 3| 3| 2| 3| 8| 3| 3| 3| 6| 7| 9| 4| 3| 3| 1| 3| 1| 3| 3| 3| 4|            |
                                           | 4| 3| 5| 4| 4| 4| 9| 2| 1| 4| 4| 1| 7| 1| 9| 2| 4| 4| 8| 4| 1| 5| 0| 4| 9|            |
 _____________________________________________________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     O      |
   FISCHER 344 RATS MALE                   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     T      |
                               ANIMAL ID   | 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4|     A      |
    1.0                                    | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|     L      |
    MG/M3                                  | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 GENITAL SYSTEM - cont                     |                                                                          |            |
                                           |                                                                          |            |
      Leukemia Mononuclear                 |                X                                                         |          3 |
      Mesothelioma Malignant               |                                                                         X|          1 |
                                            __________________________________________________________________________|____________|
   Testes                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Mesothelioma Malignant               |                         X                                               X|          2 |
      Bilateral, Interstitial Cell, Adenoma| X  X  X  X        X        X  X        X  X  X  X        X  X  X  X     X|         26 |
      Interstitial Cell, Adenoma           |             X                                      X                     |          7 |
 _____________________________________________________________________________________________________________________|            |
 HEMATOPOIETIC SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +|  48        |
      Leukemia Mononuclear                 |                X        X  X                 X              X            |         10 |
                                            __________________________________________________________________________|____________|
   Lymph Node                              |    +           +           +                             +        +      |   9        |
      Leukemia Mononuclear                 |                X                                                         |          1 |
      Iliac, Leukemia Mononuclear          |                X                                                         |          1 |
      Pancreatic, Leukemia Mononuclear     |                X           X                                             |          6 |
      Renal, Leukemia Mononuclear          |    X           X                                                         |          3 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Bronchial                   | +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  A  +  +  +  +  +  +|  41        |
      Leukemia Mononuclear                 |    X           X  X     X  X     X     X     X              X        X   |         15 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mandibular                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +|  47        |
      Leukemia Mononuclear                 |    X           X  X     X  X     X           X  X           X        X   |         18 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +|  48        |
      Leukemia Mononuclear                 |    X           X  X     X  X     X     X     X  X           X  X     X   |         22 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mediastinal                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  A  +  +  +  +  +  +|  44        |
      Leukemia Mononuclear                 |    X           X  X     X  X     X     X     X  X           X        X   |         20 |
                                            __________________________________________________________________________|____________|
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +|  49        |
      Leukemia Mononuclear                 | X  X           X  X     X  X  X  X     X     X  X        X  X  X     X   |         29 |
      Mesothelioma Malignant               |                                                                         X|          1 |
                                            __________________________________________________________________________|____________|
   Thymus                                  | +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +|  47        |
      Leukemia Mononuclear                 |                X           X                                             |          6 |
      Thymoma Benign                       |                                                          X               |          1 |
 _____________________________________________________________________________________________________________________|            |
 INTEGUMENTARY SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Mammary Gland                           | +  +  +  M  M  +  +  +  M  +  M  M  +  +  +  +  +  +  +  +  M  M  +  +  +|  36        |
      Fibroadenoma                         |                                                                          |          2 |
                                            __________________________________________________________________________|____________|
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Subcutaneous Tissue, Fibroma         |    X                                            X                        |          2 |
      Subcutaneous Tissue, Fibrosarcoma    |    X                                                                     |          1 |
      Subcutaneous Tissue, Lipoma          |                                        X                                 |          1 |
 _____________________________________________________________________________________________________________________|            |
 MUSCULOSKELETAL SYSTEM                    |                                                                          |            |
                                           |                                                                          |            |
 __________________________________________________________________________________________________________________________________ 

                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  

                                                             Page  53                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 6| 7| 7| 7| 7| 7| 6| 6| 7| 7| 6| 4| 6| 6| 6| 7| 7| 5| 7| 6| 7| 6| 7| 6|            |
                             DAY ON TEST   | 3| 7| 3| 3| 3| 3| 2| 3| 8| 3| 3| 3| 6| 7| 9| 4| 3| 3| 1| 3| 1| 3| 3| 3| 4|            |
                                           | 4| 3| 5| 4| 4| 4| 9| 2| 1| 4| 4| 1| 7| 1| 9| 2| 4| 4| 8| 4| 1| 5| 0| 4| 9|            |
 _____________________________________________________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     O      |
   FISCHER 344 RATS MALE                   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     T      |
                               ANIMAL ID   | 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4|     A      |
    1.0                                    | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|     L      |
    MG/M3                                  | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 MUSCULOSKELETAL SYSTEM - cont             |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Skeletal Muscle                         |                                                                          |   1        |
      Leukemia Mononuclear                 |                                                                          |          1 |
 _____________________________________________________________________________________________________________________|            |
 NERVOUS SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Astrocytoma Malignant                |                                                                          |          1 |
      Leukemia Mononuclear                 |                                              X                           |          3 |
                                            __________________________________________________________________________|____________|
   Spinal Cord                             |                                                                          |   1        |
      Leukemia Mononuclear                 |                                                                          |          1 |
 _____________________________________________________________________________________________________________________|            |
 RESPIRATORY SYSTEM                        |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
      Leukemia Mononuclear                 |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +|  48        |
      Alveolar/Bronchiolar Adenoma         |                                                                          |          1 |
      Alveolar/Bronchiolar Carcinoma       |                                           X              X               |          3 |
      Leukemia Mononuclear                 | X  X           X  X     X  X     X     X     X  X           X        X   |         23 |
                                            __________________________________________________________________________|____________|
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +|  49        |
      Leukemia Mononuclear                 |                X        X                                                |          5 |
                                            __________________________________________________________________________|____________|
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +|  48        |
 _____________________________________________________________________________________________________________________|            |
 SPECIAL SENSES SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Eye                                     |                                                                          |   1        |
 _____________________________________________________________________________________________________________________|            |
 URINARY SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +|  48        |
      Leukemia Mononuclear                 |    X           X  X     X  X     X           X  X           X            |         18 |
      Mesothelioma Malignant               |                                                                         X|          1 |
      Renal Tubule, Adenoma                |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Urinary Bladder                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +|  48        |
      Leukemia Mononuclear                 |                X                             X                           |          6 |
      Mesothelioma Malignant               |                                                                         X|          1 |
 __________________________________________________________________________________________________________________________________ 
 SYSTEMIC LESIONS                          |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Multiple Organs                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 | X  X           X  X     X  X  X  X     X     X  X        X  X  X     X   |         29 |
      Mesothelioma Malignant               |                         X                                               X|          2 |
 __________________________________________________________________________________________________________________________________ 

                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  

                                                             Page  54                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 5| 7| 7| 5| 6| 7| 5| 6| 7| 6| 7| 4| 6| 6| 4| 7| 7| 5| 5| 5| 5| 7| 6| 6| 5|             
                             DAY ON TEST   | 8| 3| 3| 4| 9| 0| 1| 6| 3| 8| 3| 6| 4| 3| 6| 3| 3| 2| 7| 6| 3| 2| 4| 3| 9|             
                                           | 9| 5| 5| 5| 4| 6| 1| 9| 4| 0| 4| 3| 6| 2| 3| 4| 4| 6| 9| 2| 4| 0| 3| 8| 3|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   FISCHER 344 RATS MALE                   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6|             
    3.0                                    | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
    MG/M3                                  | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 ALIMENTARY SYSTEM                         |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Esophagus                               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Colon                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Cecum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Duodenum               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Jejunum                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Ileum                  | +  +  +  +  +  +  +  +  +  I  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hepatocellular Adenoma               |                                                                          |             
      Leukemia Mononuclear                 | X           X     X  X  X              X  X     X  X  X  X  X        X   |             
                                            __________________________________________________________________________|             
   Mesentery                               |             +                       +     +  +           +        +     +|             
      Leukemia Mononuclear                 |                                           X                              |             
                                            __________________________________________________________________________|             
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Adenoma                              |                                                                          |             
      Leukemia Mononuclear                 | X                                      X           X        X            |             
      Mixed Tumor Malignant                |                                                                          |             
                                            __________________________________________________________________________|             
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 | X                                      X                    X            |             
                                            __________________________________________________________________________|             
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 | X                                      X                    X            |             
      Schwannoma Malignant                 |                                                                X         |             
                                            __________________________________________________________________________|             
   Tongue                                  |    +                          +                                          |             
                                            __________________________________________________________________________|             
   Tooth                                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 CARDIOVASCULAR SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Blood Vessel                            |                                                                          |             
                                            __________________________________________________________________________|             
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 | X                                      X           X        X            |             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM                          |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Adenoma                              |                                                                          |             
      Leukemia Mononuclear                 | X                    X                 X  X        X  X  X  X        X   |             
                                            __________________________________________________________________________|             
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 | X                    X                 X  X        X  X     X        X   |             
      Pheochromocytoma Malignant           |                X                                                         |             
      Pheochromocytoma Benign              |          X     X     X  X  X                 X                 X  X  X   |             
      Bilateral, Pheochromocytoma Benign   |    X  X                                            X                     |             
                                            __________________________________________________________________________|             
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Adenoma                              |                               X                                      X   |             
      Carcinoma                            |    X           X                                               X         |             
                                            __________________________________________________________________________|             
   Parathyroid Gland                       | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Pituitary Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             

                                                             Page  55                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 5| 7| 7| 5| 6| 7| 5| 6| 7| 6| 7| 4| 6| 6| 4| 7| 7| 5| 5| 5| 5| 7| 6| 6| 5|             
                             DAY ON TEST   | 8| 3| 3| 4| 9| 0| 1| 6| 3| 8| 3| 6| 4| 3| 6| 3| 3| 2| 7| 6| 3| 2| 4| 3| 9|             
                                           | 9| 5| 5| 5| 4| 6| 1| 9| 4| 0| 4| 3| 6| 2| 3| 4| 4| 6| 9| 2| 4| 0| 3| 8| 3|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   FISCHER 344 RATS MALE                   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6|             
    3.0                                    | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
    MG/M3                                  | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM - cont                   |                                                                          |             
                                           |                                                                          |             
      Leukemia Mononuclear                 | X                                      X           X  X     X        X   |             
      Pars Distalis, Adenoma               |       X     X  X  X  X     X  X  X  X        X  X  X  X  X     X  X     X|             
                                            __________________________________________________________________________|             
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Bilateral, C-Cell, Adenoma           |             X                                                            |             
      C-Cell, Adenoma                      |                                                 X                        |             
      C-Cell, Carcinoma                    |                         X                                                |             
      Follicular Cell, Adenoma             |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 GENERAL BODY SYSTEM                       |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Peritoneum                              |                                                 +                        |             
      Mesothelioma Malignant               |                                                 X                        |             
 _____________________________________________________________________________________________________________________|             
 GENITAL SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Epididymis                              | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Mesothelioma Malignant               |                                                 X                        |             
                                            __________________________________________________________________________|             
   Penis                                   | +                                                                        |             
                                            __________________________________________________________________________|             
   Preputial Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Adenoma                              |                                                                      X   |             
      Carcinoma                            |                   X                                                      |             
      Leukemia Mononuclear                 | X                                                                        |             
                                            __________________________________________________________________________|             
   Prostate                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Adenoma                              |                                                                          |             
                                            __________________________________________________________________________|             
   Seminal Vesicle                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 | X                                      X                    X        X   |             
                                            __________________________________________________________________________|             
   Testes                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Mesothelioma Malignant               |                                                                          |             
      Bilateral, Interstitial Cell, Adenoma|       X  X              X     X              X  X           X        X  X|             
      Interstitial Cell, Adenoma           | X           X  X           X                       X     X               |             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 | X                                      X  X        X  X  X  X        X   |             
                                            __________________________________________________________________________|             
   Lymph Node                              | +                    +                 +           +     +  +            |             
      Leukemia Mononuclear                 |                                        X                    X            |             
      Deep Cervical, Leukemia Mononuclear  |                                                             X            |             
      Iliac, Leukemia Mononuclear          |                                        X                    X            |             
      Pancreatic, Leukemia Mononuclear     | X                                      X                 X  X            |             
      Renal, Leukemia Mononuclear          |                      X                 X           X        X            |             
                                            __________________________________________________________________________|             
   Lymph Node, Bronchial                   | +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 | X           X                          X           X  X  X  X        X   |             
                                            __________________________________________________________________________|             
   Lymph Node, Mandibular                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +|             
      Leukemia Mononuclear                 | X                                      X  X        X  X  X  X        X   |             
                                            __________________________________________________________________________|             
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 | X                                      X  X        X  X  X  X        X   |             
 _____________________________________________________________________________________________________________________|             

                                                             Page  56                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 5| 7| 7| 5| 6| 7| 5| 6| 7| 6| 7| 4| 6| 6| 4| 7| 7| 5| 5| 5| 5| 7| 6| 6| 5|             
                             DAY ON TEST   | 8| 3| 3| 4| 9| 0| 1| 6| 3| 8| 3| 6| 4| 3| 6| 3| 3| 2| 7| 6| 3| 2| 4| 3| 9|             
                                           | 9| 5| 5| 5| 4| 6| 1| 9| 4| 0| 4| 3| 6| 2| 3| 4| 4| 6| 9| 2| 4| 0| 3| 8| 3|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   FISCHER 344 RATS MALE                   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6|             
    3.0                                    | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
    MG/M3                                  | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM - cont               |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Lymph Node, Mediastinal                 | +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 | X                                      X  X        X  X  X  X        X   |             
                                            __________________________________________________________________________|             
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 | X           X     X  X  X              X  X     X  X  X  X  X        X   |             
                                            __________________________________________________________________________|             
   Thymus                                  | +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 | X                                      X  X        X  X     X            |             
 _____________________________________________________________________________________________________________________|             
 INTEGUMENTARY SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Mammary Gland                           | M  +  +  M  +  M  M  +  M  +  +  M  M  M  M  +  +  +  +  M  +  +  +  +  +|             
      Fibroadenoma                         |                                                                          |             
      Fibroadenoma, Multiple               |                                                                X         |             
                                            __________________________________________________________________________|             
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Basal Cell Carcinoma                 |                                                                          |             
      Keratoacanthoma                      |    X                                                                     |             
      Keratoacanthoma, Multiple            |                                                                          |             
      Squamous Cell Papilloma              |                                                 X                        |             
      Subcutaneous Tissue, Fibroma         |                                                                          |             
      Subcutaneous Tissue, Fibrosarcoma    |                                                                X         |             
      Subcutaneous Tissue, Lipoma          |       X                                                                  |             
      Subcutaneous Tissue, Sarcoma         |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM                    |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Skeletal Muscle                         |                                                                          |             
      Sarcoma                              |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 NERVOUS SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 | X                                      X  X        X        X            |             
 _____________________________________________________________________________________________________________________|             
 RESPIRATORY SYSTEM                        |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Alveolar/Bronchiolar Adenoma         |                X           X                                         X   |             
      Alveolar/Bronchiolar Adenoma,        |                                                                          |             
          Multiple                         |                                                                          |             
      Alveolar/Bronchiolar Carcinoma       |    X                                                                     |             
      Leukemia Mononuclear                 | X           X        X  X              X  X     X  X  X  X  X        X   |             
      Sarcoma, Metastatic, Skeletal Muscle |                                                                          |             
                                            __________________________________________________________________________|             
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 | X                                      X           X     X  X            |             
      Nasopharyngeal Duct, Squamous Cell   |                                                                          |             
          Carcinoma                        |          X                                                               |             
                                            __________________________________________________________________________|             
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             

                                                             Page  57                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 5| 7| 7| 5| 6| 7| 5| 6| 7| 6| 7| 4| 6| 6| 4| 7| 7| 5| 5| 5| 5| 7| 6| 6| 5|             
                             DAY ON TEST   | 8| 3| 3| 4| 9| 0| 1| 6| 3| 8| 3| 6| 4| 3| 6| 3| 3| 2| 7| 6| 3| 2| 4| 3| 9|             
                                           | 9| 5| 5| 5| 4| 6| 1| 9| 4| 0| 4| 3| 6| 2| 3| 4| 4| 6| 9| 2| 4| 0| 3| 8| 3|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   FISCHER 344 RATS MALE                   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6|             
    3.0                                    | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
    MG/M3                                  | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 RESPIRATORY SYSTEM - cont                 |                                                                          |             
                                           |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 SPECIAL SENSES SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Eye                                     |                                                                          |             
                                            __________________________________________________________________________|             
   Zymbal's Gland                          |                                                                          |             
      Carcinoma                            |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 | X           X     X  X                 X  X     X  X  X  X  X        X   |             
                                            __________________________________________________________________________|             
   Urinary Bladder                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 | X                                      X  X                 X            |             
 _____________________________________________________________________________________________________________________|             
 SYSTEMIC LESIONS                          |                                                                          |             
                                            __________________________________________________________________________|             
   Multiple Organs                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 | X           X     X  X  X              X  X     X  X  X  X  X        X   |             
      Mesothelioma Malignant               |                                                 X                        |             
 _____________________________________________________________________________________________________________________|             

                                                             Page  58                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 7| 4| 7| 5| 6| 7| 6| 5| 6| 7| 5| 7| 6| 7| 5| 7| 6| 6| 6| 7| 6| 6| 6| 6|            |
                             DAY ON TEST   | 3| 3| 0| 3| 6| 6| 3| 0| 8| 0| 3| 7| 3| 3| 3| 6| 3| 6| 7| 1| 3| 1| 9| 1| 9|            |
                                           | 5| 5| 1| 4| 2| 6| 4| 4| 6| 3| 5| 4| 4| 8| 4| 7| 4| 3| 3| 1| 4| 1| 3| 1| 2|            |
 _____________________________________________________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     O      |
   FISCHER 344 RATS MALE                   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     T      |
                               ANIMAL ID   | 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6|     A      |
    3.0                                    | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|     L      |
    MG/M3                                  | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 ALIMENTARY SYSTEM                         |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Esophagus                               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Colon                  | +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Cecum                  | +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Duodenum               | +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Jejunum                | +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Ileum                  | +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
                                            __________________________________________________________________________|____________|
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hepatocellular Adenoma               |                                                       X                  |          1 |
      Leukemia Mononuclear                 |    X           X  X  X        X        X     X  X  X  X  X  X  X     X   |         27 |
                                            __________________________________________________________________________|____________|
   Mesentery                               | +                 +           +     +                    +           +  +|  14        |
      Leukemia Mononuclear                 |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Adenoma                              |                                                                   X      |          1 |
      Leukemia Mononuclear                 |                                                                X         |          5 |
      Mixed Tumor Malignant                |                                                             X            |          1 |
                                            __________________________________________________________________________|____________|
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |                                                                      X   |          4 |
                                            __________________________________________________________________________|____________|
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |                                                                      X   |          4 |
      Schwannoma Malignant                 |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Tongue                                  |                                                                          |   2        |
                                            __________________________________________________________________________|____________|
   Tooth                                   | +                                                                        |   1        |
 _____________________________________________________________________________________________________________________|            |
 CARDIOVASCULAR SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Blood Vessel                            |                                  +                                       |   1        |
                                            __________________________________________________________________________|____________|
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |                X                                               X     X   |          7 |
 _____________________________________________________________________________________________________________________|            |
 ENDOCRINE SYSTEM                          |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Adenoma                              |                         X                                                |          1 |
      Leukemia Mononuclear                 |                X              X                                X     X   |         13 |
                                            __________________________________________________________________________|____________|
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |                               X                                X     X   |         11 |
      Pheochromocytoma Malignant           |                                                    X                     |          2 |
      Pheochromocytoma Benign              | X  X     X                    X                    X                 X   |         15 |
      Bilateral, Pheochromocytoma Benign   |                                        X              X                  |          5 |
 __________________________________________________________________________________________________________________________________ 

                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  

                                                             Page  59                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 7| 4| 7| 5| 6| 7| 6| 5| 6| 7| 5| 7| 6| 7| 5| 7| 6| 6| 6| 7| 6| 6| 6| 6|            |
                             DAY ON TEST   | 3| 3| 0| 3| 6| 6| 3| 0| 8| 0| 3| 7| 3| 3| 3| 6| 3| 6| 7| 1| 3| 1| 9| 1| 9|            |
                                           | 5| 5| 1| 4| 2| 6| 4| 4| 6| 3| 5| 4| 4| 8| 4| 7| 4| 3| 3| 1| 4| 1| 3| 1| 2|            |
 _____________________________________________________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     O      |
   FISCHER 344 RATS MALE                   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     T      |
                               ANIMAL ID   | 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6|     A      |
    3.0                                    | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|     L      |
    MG/M3                                  | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 ENDOCRINE SYSTEM - cont                   |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Adenoma                              |                                                    X           X  X      |          5 |
      Carcinoma                            | X                                      X              X           X      |          7 |
                                            __________________________________________________________________________|____________|
   Parathyroid Gland                       | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Pituitary Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Leukemia Mononuclear                 |                X              X                                X     X   |         10 |
      Pars Distalis, Adenoma               | X  X  X  X  X     X  X  X  X  X  X  X  X  X  X  X  X  X  X  X  X  X  X  X|         41 |
                                            __________________________________________________________________________|____________|
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Bilateral, C-Cell, Adenoma           |                                                                          |          1 |
      C-Cell, Adenoma                      |    X                    X                                                |          3 |
      C-Cell, Carcinoma                    |             X                 X                                          |          3 |
      Follicular Cell, Adenoma             |                                           X                              |          1 |
 _____________________________________________________________________________________________________________________|            |
 GENERAL BODY SYSTEM                       |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Peritoneum                              |                                                                          |   1        |
      Mesothelioma Malignant               |                                                                          |          1 |
 _____________________________________________________________________________________________________________________|            |
 GENITAL SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Epididymis                              | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Mesothelioma Malignant               |                            X                                             |          2 |
                                            __________________________________________________________________________|____________|
   Penis                                   |                                                                      +   |   2        |
                                            __________________________________________________________________________|____________|
   Preputial Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Adenoma                              |                                                                          |          1 |
      Carcinoma                            | X                                                     X                  |          3 |
      Leukemia Mononuclear                 |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Prostate                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Adenoma                              |          X                                                               |          1 |
                                            __________________________________________________________________________|____________|
   Seminal Vesicle                         | +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Leukemia Mononuclear                 |                                                                          |          4 |
                                            __________________________________________________________________________|____________|
   Testes                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Mesothelioma Malignant               |                            X                                             |          1 |
      Bilateral, Interstitial Cell, Adenoma|    X     X     X              X     X     X     X     X        X        X|         19 |
      Interstitial Cell, Adenoma           | X                 X     X                                         X      |         10 |
 _____________________________________________________________________________________________________________________|            |
 HEMATOPOIETIC SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |                X                       X           X  X        X     X   |         14 |
                                            __________________________________________________________________________|____________|
   Lymph Node                              |                   +           +           +                              |   9        |
      Leukemia Mononuclear                 |                                                                          |          2 |
 __________________________________________________________________________________________________________________________________ 

                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  

                                                             Page  60                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 7| 4| 7| 5| 6| 7| 6| 5| 6| 7| 5| 7| 6| 7| 5| 7| 6| 6| 6| 7| 6| 6| 6| 6|            |
                             DAY ON TEST   | 3| 3| 0| 3| 6| 6| 3| 0| 8| 0| 3| 7| 3| 3| 3| 6| 3| 6| 7| 1| 3| 1| 9| 1| 9|            |
                                           | 5| 5| 1| 4| 2| 6| 4| 4| 6| 3| 5| 4| 4| 8| 4| 7| 4| 3| 3| 1| 4| 1| 3| 1| 2|            |
 _____________________________________________________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     O      |
   FISCHER 344 RATS MALE                   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     T      |
                               ANIMAL ID   | 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6|     A      |
    3.0                                    | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|     L      |
    MG/M3                                  | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 HEMATOPOIETIC SYSTEM - cont               |                                                                          |            |
                                           |                                                                          |            |
      Deep Cervical, Leukemia Mononuclear  |                                                                          |          1 |
      Iliac, Leukemia Mononuclear          |                                                                          |          2 |
      Pancreatic, Leukemia Mononuclear     |                                                                          |          4 |
      Renal, Leukemia Mononuclear          |                               X                                          |          5 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Bronchial                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Leukemia Mononuclear                 |                X              X        X           X     X     X     X   |         15 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mandibular                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Leukemia Mononuclear                 |                X              X        X           X           X     X   |         14 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |                X              X        X           X  X  X     X     X   |         16 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mediastinal                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Leukemia Mononuclear                 |                X  X  X        X        X           X           X     X   |         16 |
                                            __________________________________________________________________________|____________|
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |    X           X  X  X        X        X  X  X  X  X  X  X  X  X     X   |         28 |
                                            __________________________________________________________________________|____________|
   Thymus                                  | +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
      Leukemia Mononuclear                 |                X              X                                X     X   |         10 |
 _____________________________________________________________________________________________________________________|            |
 INTEGUMENTARY SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Mammary Gland                           | +  +  +  +  +  +  +  +  +  +  M  M  +  +  +  +  +  +  +  +  +  +  +  +  +|  38        |
      Fibroadenoma                         |          X                          X                                X   |          3 |
      Fibroadenoma, Multiple               |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Basal Cell Carcinoma                 |                   X                                                      |          1 |
      Keratoacanthoma                      |          X                                                               |          2 |
      Keratoacanthoma, Multiple            |                                     X                                    |          1 |
      Squamous Cell Papilloma              |                                                                          |          1 |
      Subcutaneous Tissue, Fibroma         |    X                                               X                     |          2 |
      Subcutaneous Tissue, Fibrosarcoma    |                                                             X            |          2 |
      Subcutaneous Tissue, Lipoma          |                                                                          |          1 |
      Subcutaneous Tissue, Sarcoma         |                                                                         X|          1 |
 _____________________________________________________________________________________________________________________|            |
 MUSCULOSKELETAL SYSTEM                    |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Skeletal Muscle                         |                                                                +         |   1        |
      Sarcoma                              |                                                                X         |          1 |
 _____________________________________________________________________________________________________________________|            |
 NERVOUS SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |                                                                      X   |          6 |
 __________________________________________________________________________________________________________________________________ 

                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  

                                                             Page  61                                                               
NTP Experiment-Test: 05156-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/17/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:39:09  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 7| 4| 7| 5| 6| 7| 6| 5| 6| 7| 5| 7| 6| 7| 5| 7| 6| 6| 6| 7| 6| 6| 6| 6|            |
                             DAY ON TEST   | 3| 3| 0| 3| 6| 6| 3| 0| 8| 0| 3| 7| 3| 3| 3| 6| 3| 6| 7| 1| 3| 1| 9| 1| 9|            |
                                           | 5| 5| 1| 4| 2| 6| 4| 4| 6| 3| 5| 4| 4| 8| 4| 7| 4| 3| 3| 1| 4| 1| 3| 1| 2|            |
 _____________________________________________________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     O      |
   FISCHER 344 RATS MALE                   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|     T      |
                               ANIMAL ID   | 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6|     A      |
    3.0                                    | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|     L      |
    MG/M3                                  | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 NERVOUS SYSTEM - cont                     |                                                                          |            |
                                           |                                                                          |            |
 _____________________________________________________________________________________________________________________|            |
 RESPIRATORY SYSTEM                        |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Alveolar/Bronchiolar Adenoma         |          X                                                  X            |          5 |
      Alveolar/Bronchiolar Adenoma,        |                                                                          |            |
          Multiple                         |                                                       X                  |          1 |
      Alveolar/Bronchiolar Carcinoma       |                                                                          |          1 |
      Leukemia Mononuclear                 |                X     X        X        X     X     X  X  X     X     X   |         22 |
      Sarcoma, Metastatic, Skeletal Muscle |                                                                X         |          1 |
                                            __________________________________________________________________________|____________|
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |                               X        X                                 |          7 |
      Nasopharyngeal Duct, Squamous Cell   |                                                                          |            |
          Carcinoma                        |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 SPECIAL SENSES SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Eye                                     |                                                 +                        |   1        |
                                            __________________________________________________________________________|____________|
   Zymbal's Gland                          |       +                                      +                           |   2        |
      Carcinoma                            |       X                                      X                           |          2 |
 _____________________________________________________________________________________________________________________|            |
 URINARY SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |                X     X        X        X           X           X     X   |         19 |
                                            __________________________________________________________________________|____________|
   Urinary Bladder                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |                                                                X     X   |          6 |
 __________________________________________________________________________________________________________________________________ 
 SYSTEMIC LESIONS                          |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Multiple Organs                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leukemia Mononuclear                 |    X           X  X  X        X        X  X  X  X  X  X  X  X  X     X   |         28 |
      Mesothelioma Malignant               |                            X                                             |          2 |
 __________________________________________________________________________________________________________________________________ 

                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  

                                                             Page  62                                                               
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