National Toxicology Program

National Toxicology Program
https://ntp.niehs.nih.gov/go/2534

TDMS Study 05156-06 Pathology Tables

NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53




       Facility:  Battelle Northwest

       Chemical CAS #:  10026-24-1

       Lock Date:  07/12/94

       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: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 6| 7| 6| 7| 5| 6| 7| 6| 7| 7| 7| 7| 7| 5| 7| 7| 7| 7| 7| 6| 7| 7| 7| 6|             
                             DAY ON TEST   | 3| 1| 3| 5| 3| 9| 3| 3| 7| 3| 3| 3| 3| 3| 8| 3| 3| 3| 3| 3| 5| 3| 3| 3| 9|             
                                           | 5| 9| 6| 6| 6| 6| 9| 5| 7| 4| 4| 5| 5| 5| 3| 5| 5| 6| 4| 6| 2| 5| 6| 5| 9|             
 _____________________________________________________________________________________________________________________|             
                                           | 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|             
   B6C3F1 MICE 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                               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Gallbladder                             | +  A  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Colon                  | +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Cecum                  | +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Duodenum               | +  A  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Jejunum                | +  A  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Ileum                  | +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hemangiosarcoma                      |                                                                      X   |             
      Hepatocellular Carcinoma             |    X                       X     X     X              X                  |             
      Hepatocellular Adenoma               |             X                                   X        X               |             
      Hepatocellular Adenoma, Multiple     |                                                                X         |             
      Hepatocholangiocarcinoma             |                                                                          |             
      Histiocytic Sarcoma                  |          X              X                                               X|             
      Lymphoma Malignant                   |       X                                         X                        |             
                                            __________________________________________________________________________|             
   Mesentery                               |       +              +     +                                   +     +   |             
      Hepatocholangiocarcinoma, Metastatic,|                                                                          |             
           Liver                           |                                                                          |             
      Sarcoma                              |                                                                          |             
                                            __________________________________________________________________________|             
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Histiocytic Sarcoma                  |                                                                         X|             
      Lymphoma Malignant                   |       X                                                                  |             
                                            __________________________________________________________________________|             
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Squamous Cell Papilloma              |                                                                          |             
                                            __________________________________________________________________________|             
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Muscularis, Serosa, Sarcoma          |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 CARDIOVASCULAR SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hepatocholangiocarcinoma, Metastatic,|                                                                          |             
           Liver                           |                                                                          |             
      Lymphoma Malignant                   |       X                                                                  |             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM                          |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Lymphoma Malignant                   |       X                                                                  |             
                                            __________________________________________________________________________|             
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Adenoma                              |                                                                          |             
                                            __________________________________________________________________________|             
   Parathyroid Gland                       | +  +  M  M  M  M  +  M  M  M  +  +  +  +  +  +  +  +  M  M  +  +  M  +  +|             
                                            __________________________________________________________________________|             
   Pituitary Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  I  I  +  +  +  +  +  +  +  +  +  +|             
      Pars Distalis, Adenoma               |             X  X                             X        X                  |             
 _____________________________________________________________________________________________________________________|             

                                                             Page   2                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 6| 7| 6| 7| 5| 6| 7| 6| 7| 7| 7| 7| 7| 5| 7| 7| 7| 7| 7| 6| 7| 7| 7| 6|             
                             DAY ON TEST   | 3| 1| 3| 5| 3| 9| 3| 3| 7| 3| 3| 3| 3| 3| 8| 3| 3| 3| 3| 3| 5| 3| 3| 3| 9|             
                                           | 5| 9| 6| 6| 6| 6| 9| 5| 7| 4| 4| 5| 5| 5| 3| 5| 5| 6| 4| 6| 2| 5| 6| 5| 9|             
 _____________________________________________________________________________________________________________________|             
                                           | 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|             
   B6C3F1 MICE 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|             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM - cont                   |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Follicular Cell, Adenoma             |    X                                            X                 X      |             
      Follicular Cell, Carcinoma           |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 GENERAL BODY SYSTEM                       |                                                                          |             
                                           |                                                                          |             
    None                                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 GENITAL SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Clitoral Gland                          | +  +  +  +  +  +  +  +  M  +  +  M  +  +  +  +  +  +  M  +  +  M  M  +  M|             
                                            __________________________________________________________________________|             
   Ovary                                   | +  +  +  +  +  +  +  +  +  I  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Arrhenoblastoma Benign               |                                                                          |             
      Cystadenoma                          |                                                                X         |             
      Granulosa Cell Tumor Benign          | X                                                                        |             
      Histiocytic Sarcoma                  |                                                                         X|             
      Luteoma                              |                                                       X                  |             
      Lymphoma Malignant                   |                                           X                              |             
      Teratoma Benign                      |                                                                   X      |             
      Periovarian Tissue, Lymphoma         |                                                                          |             
          Malignant                        |       X                                                                  |             
                                            __________________________________________________________________________|             
   Uterus                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Histiocytic Sarcoma                  |                                                                         X|             
      Leiomyoma                            |                                                    X                     |             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Histiocytic Sarcoma                  |                                                                         X|             
      Lymphoma Malignant                   |       X                                                                  |             
                                            __________________________________________________________________________|             
   Lymph Node                              |       +  +                                                              +|             
      Histiocytic Sarcoma                  |                                                                         X|             
      Lymphoma Malignant                   |       X                                                                  |             
      Iliac, Lymphoma Malignant            |       X                                                                  |             
      Inguinal, Lymphoma Malignant         |       X                                                                  |             
      Lumbar, Histiocytic Sarcoma          |                                                                         X|             
      Popliteal, Lymphoma Malignant        |       X                                                                  |             
      Renal, Histiocytic Sarcoma           |          X                                                              X|             
      Renal, Lymphoma Malignant            |       X                                                                  |             
                                            __________________________________________________________________________|             
   Lymph Node, Bronchial                   | +  M  +  M  +  M  M  +  +  +  M  M  +  +  M  +  +  +  +  +  M  +  +  +  M|             
      Hepatocholangiocarcinoma, Metastatic,|                                                                          |             
           Liver                           |                                                                          |             
      Histiocytic Sarcoma                  |                         X                                                |             
      Lymphoma Malignant                   |       X                                         X                        |             
                                            __________________________________________________________________________|             
   Lymph Node, Mandibular                  | +  +  +  +  M  +  +  +  +  M  +  +  +  +  +  +  +  M  +  +  +  M  M  M  +|             
      Histiocytic Sarcoma                  |                         X                                               X|             
      Lymphoma Malignant                   |       X                                                                  |             
 _____________________________________________________________________________________________________________________|             

                                                             Page   3                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 6| 7| 6| 7| 5| 6| 7| 6| 7| 7| 7| 7| 7| 5| 7| 7| 7| 7| 7| 6| 7| 7| 7| 6|             
                             DAY ON TEST   | 3| 1| 3| 5| 3| 9| 3| 3| 7| 3| 3| 3| 3| 3| 8| 3| 3| 3| 3| 3| 5| 3| 3| 3| 9|             
                                           | 5| 9| 6| 6| 6| 6| 9| 5| 7| 4| 4| 5| 5| 5| 3| 5| 5| 6| 4| 6| 2| 5| 6| 5| 9|             
 _____________________________________________________________________________________________________________________|             
                                           | 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|             
   B6C3F1 MICE 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|             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM - cont               |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  +  +  I  +  I  +  +  +  +  +  +  +  +  +  I  +  +|             
      Histiocytic Sarcoma                  |          X              X                                               X|             
      Lymphoma Malignant                   |       X                                                                  |             
                                            __________________________________________________________________________|             
   Lymph Node, Mediastinal                 | +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  M  M  +  +  +  M  +  +|             
      Hepatocholangiocarcinoma, Metastatic,|                                                                          |             
           Liver                           |                                                                          |             
      Histiocytic Sarcoma                  |          X              X                                               X|             
      Lymphoma Malignant                   |       X                                   X     X                        |             
                                            __________________________________________________________________________|             
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Histiocytic Sarcoma                  |          X              X                                               X|             
      Lymphoma Malignant                   |       X                                         X                        |             
                                            __________________________________________________________________________|             
   Thymus                                  | M  +  +  +  +  M  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Histiocytic Sarcoma                  |                                                                         X|             
      Lymphoma Malignant                   |       X                                   X     X                        |             
 _____________________________________________________________________________________________________________________|             
 INTEGUMENTARY SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Mammary Gland                           | +  I  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M|             
      Carcinoma                            |                                                                          |             
                                            __________________________________________________________________________|             
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  I|             
      Squamous Cell Carcinoma              |                   X                                                      |             
      Subcutaneous Tissue, Lymphoma        |                                                                          |             
          Malignant                        |       X                                                                  |             
      Subcutaneous Tissue, Sarcoma         |       X              X              X                                    |             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM                    |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 NERVOUS SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Spinal Cord                             |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 RESPIRATORY SYSTEM                        |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Alveolar/Bronchiolar Adenoma         |             X                       X  X                                 |             
      Alveolar/Bronchiolar Carcinoma       |                                                                          |             
      Hepatocellular Carcinoma, Metastatic,|                                                                          |             
           Liver                           |                            X     X                                       |             
      Hepatocholangiocarcinoma, Metastatic,|                                                                          |             
           Liver                           |                                                                          |             
      Histiocytic Sarcoma                  |          X              X                                               X|             
      Lymphoma Malignant                   |       X                                   X     X                        |             
      Sarcoma, Metastatic, Skin            |                                                                          |             
                                            __________________________________________________________________________|             
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             

                                                             Page   4                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 6| 7| 6| 7| 5| 6| 7| 6| 7| 7| 7| 7| 7| 5| 7| 7| 7| 7| 7| 6| 7| 7| 7| 6|             
                             DAY ON TEST   | 3| 1| 3| 5| 3| 9| 3| 3| 7| 3| 3| 3| 3| 3| 8| 3| 3| 3| 3| 3| 5| 3| 3| 3| 9|             
                                           | 5| 9| 6| 6| 6| 6| 9| 5| 7| 4| 4| 5| 5| 5| 3| 5| 5| 6| 4| 6| 2| 5| 6| 5| 9|             
 _____________________________________________________________________________________________________________________|             
                                           | 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|             
   B6C3F1 MICE 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|             
 _____________________________________________________________________________________________________________________|             
 RESPIRATORY SYSTEM - cont                 |                                                                          |             
                                           |                                                                          |             
      Lymphoma Malignant                   |       X                                                                  |             
                                            __________________________________________________________________________|             
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 SPECIAL SENSES SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Eye                                     |                                                                          |             
                                            __________________________________________________________________________|             
   Harderian Gland                         | +                                                                        |             
      Adenoma                              | X                                                                        |             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Histiocytic Sarcoma                  |                         X                                               X|             
      Lymphoma Malignant                   |       X                                                                  |             
                                            __________________________________________________________________________|             
   Urinary Bladder                         | +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Histiocytic Sarcoma                  |                                                                         X|             
      Lymphoma Malignant                   |                                           X                              |             
 _____________________________________________________________________________________________________________________|             
 SYSTEMIC LESIONS                          |                                                                          |             
                                            __________________________________________________________________________|             
   Multiple Organs                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Histiocytic Sarcoma                  |          X              X                                               X|             
      Lymphoma Malignant                   |       X                                   X     X                        |             
 _____________________________________________________________________________________________________________________|             

                                                             Page   5                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 5| 6| 7| 7| 7| 7| 7| 7| 7| 2| 5| 7| 7| 7| 7| 7| 7| 7| 7| 6| 7| 6| 7| 6|            |
                             DAY ON TEST   | 3| 3| 4| 3| 3| 3| 3| 3| 3| 3| 2| 5| 3| 3| 3| 3| 3| 3| 3| 1| 2| 3| 0| 3| 9|            |
                                           | 5| 1| 3| 5| 6| 6| 6| 5| 6| 5| 5| 9| 6| 4| 6| 5| 6| 6| 5| 3| 0| 6| 9| 6| 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      |
   B6C3F1 MICE 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        |
                                            __________________________________________________________________________|____________|
   Gallbladder                             | +  +  +  +  +  +  M  +  +  +  M  +  +  +  +  +  +  +  +  +  A  +  A  +  A|  43        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Colon                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Cecum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Duodenum               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|  47        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Jejunum                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Ileum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +|  48        |
                                            __________________________________________________________________________|____________|
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hemangiosarcoma                      |                                                                          |          1 |
      Hepatocellular Carcinoma             | X        X              X           X     X              X        X      |         12 |
      Hepatocellular Adenoma               | X           X                                            X           X   |          7 |
      Hepatocellular Adenoma, Multiple     |                                                                          |          1 |
      Hepatocholangiocarcinoma             |                                                             X           X|          2 |
      Histiocytic Sarcoma                  |                                                                          |          3 |
      Lymphoma Malignant                   |                                                                          |          2 |
                                            __________________________________________________________________________|____________|
   Mesentery                               |                         +        +     +           +        +            |  10        |
      Hepatocholangiocarcinoma, Metastatic,|                                                                          |            |
           Liver                           |                                                             X            |          1 |
      Sarcoma                              |                                                    X                     |          1 |
                                            __________________________________________________________________________|____________|
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Histiocytic Sarcoma                  |                                                                          |          1 |
      Lymphoma Malignant                   |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Squamous Cell Papilloma              |                            X                                             |          1 |
                                            __________________________________________________________________________|____________|
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Muscularis, Serosa, Sarcoma          |                                                    X                     |          1 |
 _____________________________________________________________________________________________________________________|            |
 CARDIOVASCULAR SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hepatocholangiocarcinoma, Metastatic,|                                                                          |            |
           Liver                           |                                                                         X|          1 |
      Lymphoma Malignant                   |                                                                          |          1 |
 _____________________________________________________________________________________________________________________|            |
 ENDOCRINE SYSTEM                          |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Lymphoma Malignant                   |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  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   6                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 5| 6| 7| 7| 7| 7| 7| 7| 7| 2| 5| 7| 7| 7| 7| 7| 7| 7| 7| 6| 7| 6| 7| 6|            |
                             DAY ON TEST   | 3| 3| 4| 3| 3| 3| 3| 3| 3| 3| 2| 5| 3| 3| 3| 3| 3| 3| 3| 1| 2| 3| 0| 3| 9|            |
                                           | 5| 1| 3| 5| 6| 6| 6| 5| 6| 5| 5| 9| 6| 4| 6| 5| 6| 6| 5| 3| 0| 6| 9| 6| 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      |
   B6C3F1 MICE 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                   |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Adenoma                              |                X                                                         |          1 |
                                            __________________________________________________________________________|____________|
   Parathyroid Gland                       | M  +  M  M  +  +  +  M  +  M  +  M  M  M  +  M  M  M  +  +  M  +  M  M  M|  25        |
                                            __________________________________________________________________________|____________|
   Pituitary Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
      Pars Distalis, Adenoma               |             X        X  X  X              X              X              X|         11 |
                                            __________________________________________________________________________|____________|
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Follicular Cell, Adenoma             |                                                                          |          3 |
      Follicular Cell, Carcinoma           |                                                          X               |          1 |
 _____________________________________________________________________________________________________________________|            |
 GENERAL BODY SYSTEM                       |                                                                          |            |
                                           |                                                                          |            |
    None                                   |                                                                          |            |
 _____________________________________________________________________________________________________________________|            |
 GENITAL SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Clitoral Gland                          | +  +  +  +  +  +  M  +  +  +  M  +  +  +  +  +  M  +  +  +  +  +  +  +  +|  41        |
                                            __________________________________________________________________________|____________|
   Ovary                                   | +  +  +  +  +  +  I  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
      Arrhenoblastoma Benign               |                                                                X         |          1 |
      Cystadenoma                          |                                                       X                  |          2 |
      Granulosa Cell Tumor Benign          |                                                                          |          1 |
      Histiocytic Sarcoma                  |                                                                          |          1 |
      Luteoma                              |                                                                          |          1 |
      Lymphoma Malignant                   |                                                                          |          1 |
      Teratoma Benign                      |                                                                          |          1 |
      Periovarian Tissue, Lymphoma         |                                                                          |            |
          Malignant                        |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Uterus                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Histiocytic Sarcoma                  |                                                                          |          1 |
      Leiomyoma                            |                                                                          |          1 |
 _____________________________________________________________________________________________________________________|            |
 HEMATOPOIETIC SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Histiocytic Sarcoma                  |                                                                          |          1 |
      Lymphoma Malignant                   |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Lymph Node                              |                                                                          |   3        |
      Histiocytic Sarcoma                  |                                                                          |          1 |
      Lymphoma Malignant                   |                                                                          |          1 |
      Iliac, Lymphoma Malignant            |                                                                          |          1 |
      Inguinal, Lymphoma Malignant         |                                                                          |          1 |
      Lumbar, Histiocytic Sarcoma          |                                                                          |          1 |
      Popliteal, Lymphoma 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   7                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 5| 6| 7| 7| 7| 7| 7| 7| 7| 2| 5| 7| 7| 7| 7| 7| 7| 7| 7| 6| 7| 6| 7| 6|            |
                             DAY ON TEST   | 3| 3| 4| 3| 3| 3| 3| 3| 3| 3| 2| 5| 3| 3| 3| 3| 3| 3| 3| 1| 2| 3| 0| 3| 9|            |
                                           | 5| 1| 3| 5| 6| 6| 6| 5| 6| 5| 5| 9| 6| 4| 6| 5| 6| 6| 5| 3| 0| 6| 9| 6| 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      |
   B6C3F1 MICE 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|            |
 __________________________________________________________________________________________________________________________________ 
 HEMATOPOIETIC SYSTEM - cont               |                                                                          |            |
                                           |                                                                          |            |
      Renal, Histiocytic Sarcoma           |                                                                          |          2 |
      Renal, Lymphoma Malignant            |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Bronchial                   | +  M  M  +  +  +  +  +  +  +  M  M  M  M  M  +  +  +  M  +  +  M  M  M  +|  30        |
      Hepatocholangiocarcinoma, Metastatic,|                                                                          |            |
           Liver                           |                                                             X           X|          2 |
      Histiocytic Sarcoma                  |                                                                          |          1 |
      Lymphoma Malignant                   |          X                                                               |          3 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mandibular                  | +  +  M  +  +  +  M  +  +  M  M  M  +  +  +  +  +  +  +  +  M  M  +  +  +|  37        |
      Histiocytic Sarcoma                  |                                                                          |          2 |
      Lymphoma Malignant                   |          X                                                               |          2 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  I  +  +  +  +  +  +  +  +  +  +|  46        |
      Histiocytic Sarcoma                  |                                                                          |          3 |
      Lymphoma Malignant                   |          X                                                               |          2 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mediastinal                 | M  +  +  +  M  M  M  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +|  41        |
      Hepatocholangiocarcinoma, Metastatic,|                                                                          |            |
           Liver                           |                                                             X           X|          2 |
      Histiocytic Sarcoma                  |                                                                          |          3 |
      Lymphoma Malignant                   |          X                                                               |          4 |
                                            __________________________________________________________________________|____________|
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Histiocytic Sarcoma                  |                                                                          |          3 |
      Lymphoma Malignant                   |          X                                                               |          3 |
                                            __________________________________________________________________________|____________|
   Thymus                                  | +  +  +  M  +  +  +  +  +  +  +  +  M  M  +  +  +  +  +  M  +  M  +  +  M|  41        |
      Histiocytic Sarcoma                  |                                                                          |          1 |
      Lymphoma Malignant                   |                                                                          |          3 |
 _____________________________________________________________________________________________________________________|            |
 INTEGUMENTARY SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Mammary Gland                           | +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  47        |
      Carcinoma                            |       X                                                                  |          1 |
                                            __________________________________________________________________________|____________|
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Squamous Cell Carcinoma              |                                                                          |          1 |
      Subcutaneous Tissue, Lymphoma        |                                                                          |            |
          Malignant                        |                                                                          |          1 |
      Subcutaneous Tissue, Sarcoma         |                               X                    X     X               |          6 |
 _____________________________________________________________________________________________________________________|            |
 MUSCULOSKELETAL SYSTEM                    |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 NERVOUS SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  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   8                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 5| 6| 7| 7| 7| 7| 7| 7| 7| 2| 5| 7| 7| 7| 7| 7| 7| 7| 7| 6| 7| 6| 7| 6|            |
                             DAY ON TEST   | 3| 3| 4| 3| 3| 3| 3| 3| 3| 3| 2| 5| 3| 3| 3| 3| 3| 3| 3| 1| 2| 3| 0| 3| 9|            |
                                           | 5| 1| 3| 5| 6| 6| 6| 5| 6| 5| 5| 9| 6| 4| 6| 5| 6| 6| 5| 3| 0| 6| 9| 6| 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      |
   B6C3F1 MICE 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|            |
 __________________________________________________________________________________________________________________________________ 
 NERVOUS SYSTEM - cont                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Spinal Cord                             |                                                                         +|   1        |
 _____________________________________________________________________________________________________________________|            |
 RESPIRATORY SYSTEM                        |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Alveolar/Bronchiolar Adenoma         |                                                                          |          3 |
      Alveolar/Bronchiolar Carcinoma       | X                                                                        |          1 |
      Hepatocellular Carcinoma, Metastatic,|                                                                          |            |
           Liver                           |                                     X                                    |          3 |
      Hepatocholangiocarcinoma, Metastatic,|                                                                          |            |
           Liver                           |                                                             X           X|          2 |
      Histiocytic Sarcoma                  |                                                                          |          3 |
      Lymphoma Malignant                   |                                                                          |          3 |
      Sarcoma, Metastatic, Skin            |                               X                                          |          1 |
                                            __________________________________________________________________________|____________|
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Lymphoma Malignant                   |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 SPECIAL SENSES SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Eye                                     |                                                       +                  |   1        |
                                            __________________________________________________________________________|____________|
   Harderian Gland                         |                                                       +                  |   2        |
      Adenoma                              |                                                       X                  |          2 |
 _____________________________________________________________________________________________________________________|            |
 URINARY SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Histiocytic Sarcoma                  |                                                                          |          2 |
      Lymphoma Malignant                   |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Urinary Bladder                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +|  48        |
      Histiocytic Sarcoma                  |                                                                          |          1 |
      Lymphoma Malignant                   |                                                                          |          1 |
 __________________________________________________________________________________________________________________________________ 
 SYSTEMIC LESIONS                          |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Multiple Organs                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Histiocytic Sarcoma                  |                                                                          |          3 |
      Lymphoma Malignant                   |          X                                                               |          4 |
 __________________________________________________________________________________________________________________________________ 

                         * : 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   9                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 7| 6| 7| 7| 7| 7| 6| 6| 7| 7| 7| 7| 4| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7|             
                             DAY ON TEST   | 3| 3| 6| 3| 3| 3| 3| 5| 4| 3| 3| 3| 3| 8| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3|             
                                           | 5| 6| 6| 5| 6| 5| 6| 2| 9| 5| 6| 6| 5| 1| 6| 5| 5| 6| 6| 4| 4| 5| 4| 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|             
   B6C3F1 MICE 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                               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Gallbladder                             | +  +  +  +  +  M  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Colon                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Cecum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Duodenum               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Jejunum                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Ileum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Peyer's Patch, Lymphoma Malignant    |                               X                                          |             
                                            __________________________________________________________________________|             
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hepatocellular Carcinoma             |                            X        X        X        X           X      |             
      Hepatocellular Adenoma               |       X     X  X  X                                                      |             
      Hepatocellular Adenoma, Multiple     | X                                                                        |             
      Histiocytic Sarcoma                  |          X              X                                                |             
      Lymphoma Malignant                   |                                              X                           |             
                                            __________________________________________________________________________|             
   Mesentery                               |       +           +  +  +        +                                +      |             
      Hemangiosarcoma                      |                      X                                                   |             
      Histiocytic Sarcoma                  |                         X                                                |             
      Lymphoma Malignant                   |                                                                          |             
                                            __________________________________________________________________________|             
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Lymphoma Malignant                   |                                                                          |             
                                            __________________________________________________________________________|             
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Lymphoma Malignant                   |                                                                          |             
                                            __________________________________________________________________________|             
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Squamous Cell Papilloma              |                                                                   X      |             
                                            __________________________________________________________________________|             
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Lymphoma Malignant                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 CARDIOVASCULAR SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM                          |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Histiocytic Sarcoma                  |                         X                                                |             
      Lymphoma Malignant                   |                                              X                           |             
      Capsule, Adenoma                     |                                                       X                  |             
                                            __________________________________________________________________________|             
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Pheochromocytoma Benign              |                                           X                              |             
                                            __________________________________________________________________________|             
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Parathyroid Gland                       | I  M  M  +  M  +  M  +  M  M  +  M  +  +  +  +  M  +  M  M  M  M  M  +  +|             
                                            __________________________________________________________________________|             
   Pituitary Gland                         | +  +  +  I  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Pars Distalis, Adenoma               |                                                                X        X|             
                                            __________________________________________________________________________|             
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  I  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 GENERAL BODY SYSTEM                       |                                                                          |             
                                           |                                                                          |             
    None                                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             

                                                             Page  10                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 7| 6| 7| 7| 7| 7| 6| 6| 7| 7| 7| 7| 4| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7|             
                             DAY ON TEST   | 3| 3| 6| 3| 3| 3| 3| 5| 4| 3| 3| 3| 3| 8| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3|             
                                           | 5| 6| 6| 5| 6| 5| 6| 2| 9| 5| 6| 6| 5| 1| 6| 5| 5| 6| 6| 4| 4| 5| 4| 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|             
   B6C3F1 MICE 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|             
 _____________________________________________________________________________________________________________________|             
 GENITAL SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Clitoral Gland                          | +  +  +  +  +  M  +  M  +  M  +  +  +  +  +  +  +  M  M  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Ovary                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  I|             
      Cystadenocarcinoma                   |                                                             X            |             
      Cystadenoma                          | X                                         X                              |             
      Histiocytic Sarcoma                  |          X                                                               |             
      Lymphoma Malignant                   |                                              X                           |             
      Teratoma Benign                      |                                              X                           |             
      Periovarian Tissue, Lymphoma         |                                                                          |             
          Malignant                        |                                                                          |             
                                            __________________________________________________________________________|             
   Uterus                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hemangioma                           |                                                    X                     |             
      Hemangiosarcoma                      |                                     X                                    |             
      Lymphoma Malignant                   |                                                                          |             
      Polyp Stromal                        |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Lymphoma Malignant                   |                               X                                          |             
                                            __________________________________________________________________________|             
   Lymph Node                              |                                              +                           |             
      Lymphoma Malignant                   |                                              X                           |             
      Deep Cervical, Lymphoma Malignant    |                                              X                           |             
      Iliac, Lymphoma Malignant            |                                                                          |             
      Inguinal, Lymphoma Malignant         |                                              X                           |             
      Pancreatic, Lymphoma Malignant       |                                                                          |             
      Popliteal, Lymphoma Malignant        |                                              X                           |             
      Renal, Lymphoma Malignant            |                                              X                           |             
                                            __________________________________________________________________________|             
   Lymph Node, Bronchial                   | +  M  M  +  +  +  M  M  M  +  +  +  +  M  M  +  +  +  M  +  M  M  +  +  +|             
      Histiocytic Sarcoma                  |          X                                                               |             
      Lymphoma Malignant                   |                               X              X                           |             
                                            __________________________________________________________________________|             
   Lymph Node, Mandibular                  | +  +  M  +  +  +  +  M  +  +  +  +  M  M  +  +  +  +  +  M  +  +  +  +  +|             
      Histiocytic Sarcoma                  |          X              X                                                |             
      Lymphoma Malignant                   |                               X              X                           |             
                                            __________________________________________________________________________|             
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  M  +  +  +  +  +  +  I  +  +  +  +  +  M  +  +  +  +|             
      Histiocytic Sarcoma                  |          X              X                                                |             
      Lymphoma Malignant                   |                               X              X                           |             
                                            __________________________________________________________________________|             
   Lymph Node, Mediastinal                 | +  +  +  +  M  +  +  M  +  M  +  +  M  +  +  +  M  M  M  +  M  +  +  M  +|             
      Histiocytic Sarcoma                  |          X              X                                                |             
      Lymphoma Malignant                   |                               X              X           X               |             
                                            __________________________________________________________________________|             
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Histiocytic Sarcoma                  |          X              X                                                |             
      Lymphoma Malignant                   |                               X              X           X               |             
                                            __________________________________________________________________________|             
   Thymus                                  | +  +  +  +  +  +  +  M  +  +  +  +  +  M  +  +  +  +  +  M  M  +  +  +  M|             
      Histiocytic Sarcoma                  |                         X                                                |             
      Lymphoma Malignant                   |                                              X                           |             
 _____________________________________________________________________________________________________________________|             

                                                             Page  11                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 7| 6| 7| 7| 7| 7| 6| 6| 7| 7| 7| 7| 4| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7|             
                             DAY ON TEST   | 3| 3| 6| 3| 3| 3| 3| 5| 4| 3| 3| 3| 3| 8| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3|             
                                           | 5| 6| 6| 5| 6| 5| 6| 2| 9| 5| 6| 6| 5| 1| 6| 5| 5| 6| 6| 4| 4| 5| 4| 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|             
   B6C3F1 MICE 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|             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM - cont               |                                                                          |             
                                           |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 INTEGUMENTARY SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Mammary Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Carcinoma                            |                   X                                                      |             
                                            __________________________________________________________________________|             
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Subcutaneous Tissue, Lymphoma        |                                                                          |             
          Malignant                        |                                              X                           |             
      Subcutaneous Tissue, Sarcoma         |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM                    |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Skeletal Muscle                         |                                                                          |             
      Lymphoma Malignant                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 NERVOUS SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Lymphoma Malignant                   |       X                                                                  |             
 _____________________________________________________________________________________________________________________|             
 RESPIRATORY SYSTEM                        |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Larynx                                  | +  +  +  +  +  +  +  +  I  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Alveolar/Bronchiolar Adenoma         |    X                             X                          X            |             
      Alveolar/Bronchiolar Adenoma,        |                                                                          |             
          Multiple                         |                                                          X               |             
      Alveolar/Bronchiolar Carcinoma       |                                                                X         |             
      Histiocytic Sarcoma                  |          X              X                                                |             
      Lymphoma Malignant                   |                                              X                           |             
                                            __________________________________________________________________________|             
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Lymphoma Malignant                   |       X                                                                  |             
                                            __________________________________________________________________________|             
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 SPECIAL SENSES SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Harderian Gland                         |                                                                          |             
      Adenoma                              |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Histiocytic Sarcoma                  |                         X                                                |             
      Lymphoma Malignant                   |                                              X                           |             
                                            __________________________________________________________________________|             
   Urinary Bladder                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +|             
      Lymphoma Malignant                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 SYSTEMIC LESIONS                          |                                                                          |             
                                            __________________________________________________________________________|             
   Multiple Organs                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Histiocytic Sarcoma                  |          X              X                                                |             
 _____________________________________________________________________________________________________________________|             

                                                             Page  12                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 7| 6| 7| 7| 7| 7| 6| 6| 7| 7| 7| 7| 4| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7|             
                             DAY ON TEST   | 3| 3| 6| 3| 3| 3| 3| 5| 4| 3| 3| 3| 3| 8| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3|             
                                           | 5| 6| 6| 5| 6| 5| 6| 2| 9| 5| 6| 6| 5| 1| 6| 5| 5| 6| 6| 4| 4| 5| 4| 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|             
   B6C3F1 MICE 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|             
 _____________________________________________________________________________________________________________________|             
 SYSTEMIC LESIONS - cont                   |                                                                          |             
                                           |                                                                          |             
      Lymphoma Malignant                   |       X                       X              X           X               |             
 _____________________________________________________________________________________________________________________|             

                                                             Page  13                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 6| 5| 7| 7| 7| 7| 7| 6| 5| 7| 7| 7| 7| 7| 7| 7| 7| 6| 7| 7| 7| 6| 7| 7| 7|            |
                             DAY ON TEST   | 6| 9| 3| 3| 3| 2| 2| 6| 9| 3| 3| 3| 3| 3| 3| 2| 3| 9| 3| 3| 3| 6| 3| 3| 3|            |
                                           | 4| 6| 5| 4| 5| 6| 0| 6| 3| 5| 6| 5| 4| 5| 4| 7| 5| 3| 4| 5| 6| 6| 5| 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      |
   B6C3F1 MICE 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                               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Gallbladder                             | +  A  +  +  +  M  +  M  +  +  +  +  +  +  +  A  +  A  +  +  +  +  +  +  +|  43        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Colon                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Cecum                  | +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Duodenum               | +  A  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Jejunum                | +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Ileum                  | +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  48        |
      Peyer's Patch, Lymphoma Malignant    |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hepatocellular Carcinoma             |                   X  X        X                       X                  |          9 |
      Hepatocellular Adenoma               |                         X     X                                   X      |          7 |
      Hepatocellular Adenoma, Multiple     |                            X                             X               |          3 |
      Histiocytic Sarcoma                  |                                                                          |          2 |
      Lymphoma Malignant                   |                X     X                       X                           |          4 |
                                            __________________________________________________________________________|____________|
   Mesentery                               |                +     +  +              +                          +  +   |  12        |
      Hemangiosarcoma                      |                                                                          |          1 |
      Histiocytic Sarcoma                  |                                                                          |          1 |
      Lymphoma Malignant                   |                X                                                         |          1 |
                                            __________________________________________________________________________|____________|
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Lymphoma Malignant                   |                X     X                       X                           |          3 |
                                            __________________________________________________________________________|____________|
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Lymphoma Malignant                   |                X                             X                           |          2 |
                                            __________________________________________________________________________|____________|
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Squamous Cell Papilloma              |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Lymphoma Malignant                   |                X                                                         |          1 |
 _____________________________________________________________________________________________________________________|            |
 CARDIOVASCULAR SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 ENDOCRINE SYSTEM                          |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Histiocytic Sarcoma                  |                                                                          |          1 |
      Lymphoma Malignant                   |                                              X                           |          2 |
      Capsule, Adenoma                     |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Pheochromocytoma Benign              |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  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  14                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 6| 5| 7| 7| 7| 7| 7| 6| 5| 7| 7| 7| 7| 7| 7| 7| 7| 6| 7| 7| 7| 6| 7| 7| 7|            |
                             DAY ON TEST   | 6| 9| 3| 3| 3| 2| 2| 6| 9| 3| 3| 3| 3| 3| 3| 2| 3| 9| 3| 3| 3| 6| 3| 3| 3|            |
                                           | 4| 6| 5| 4| 5| 6| 0| 6| 3| 5| 6| 5| 4| 5| 4| 7| 5| 3| 4| 5| 6| 6| 5| 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      |
   B6C3F1 MICE 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                   |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Parathyroid Gland                       | +  +  M  M  M  +  +  M  M  M  +  +  +  +  M  +  M  M  M  +  +  M  M  M  +|  23        |
                                            __________________________________________________________________________|____________|
   Pituitary Gland                         | +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  I  +  +  +  +  +  +  +|  47        |
      Pars Distalis, Adenoma               |             X                 X  X  X                 X              X   |          8 |
                                            __________________________________________________________________________|____________|
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
 _____________________________________________________________________________________________________________________|            |
 GENERAL BODY SYSTEM                       |                                                                          |            |
                                           |                                                                          |            |
    None                                   |                                                                          |            |
 _____________________________________________________________________________________________________________________|            |
 GENITAL SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Clitoral Gland                          | +  +  +  +  M  +  +  +  +  +  +  +  M  +  M  +  +  +  +  M  +  +  +  +  M|  40        |
                                            __________________________________________________________________________|____________|
   Ovary                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Cystadenocarcinoma                   |                                                                          |          1 |
      Cystadenoma                          |          X                                                               |          3 |
      Histiocytic Sarcoma                  |                                                                          |          1 |
      Lymphoma Malignant                   |                X     X                                                   |          3 |
      Teratoma Benign                      |                                                                          |          1 |
      Periovarian Tissue, Lymphoma         |                                                                          |            |
          Malignant                        |                                              X                           |          1 |
                                            __________________________________________________________________________|____________|
   Uterus                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hemangioma                           |                                                                          |          1 |
      Hemangiosarcoma                      |                                                                          |          1 |
      Lymphoma Malignant                   |                X                                                         |          1 |
      Polyp Stromal                        |                                        X     X                           |          2 |
 _____________________________________________________________________________________________________________________|            |
 HEMATOPOIETIC SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Lymphoma Malignant                   |                X     X                                                   |          3 |
                                            __________________________________________________________________________|____________|
   Lymph Node                              |       +        +     +           +           +                           |   6        |
      Lymphoma Malignant                   |                      X                                                   |          2 |
      Deep Cervical, Lymphoma Malignant    |                      X                                                   |          2 |
      Iliac, Lymphoma Malignant            |                X     X                       X                           |          3 |
      Inguinal, Lymphoma Malignant         |                                                                          |          1 |
      Pancreatic, Lymphoma Malignant       |                X                                                         |          1 |
      Popliteal, Lymphoma Malignant        |                                                                          |          1 |
      Renal, Lymphoma Malignant            |                X     X                       X                           |          4 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Bronchial                   | M  M  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  M  +  +  M  +  +  +|  34        |
      Histiocytic Sarcoma                  |                                                                          |          1 |
      Lymphoma Malignant                   |                X     X                       X                           |          5 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mandibular                  | +  M  +  M  +  +  M  +  +  +  +  M  +  M  +  M  +  +  +  +  +  +  M  +  M|  37        |
 __________________________________________________________________________________________________________________________________ 

                         * : 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  15                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 6| 5| 7| 7| 7| 7| 7| 6| 5| 7| 7| 7| 7| 7| 7| 7| 7| 6| 7| 7| 7| 6| 7| 7| 7|            |
                             DAY ON TEST   | 6| 9| 3| 3| 3| 2| 2| 6| 9| 3| 3| 3| 3| 3| 3| 2| 3| 9| 3| 3| 3| 6| 3| 3| 3|            |
                                           | 4| 6| 5| 4| 5| 6| 0| 6| 3| 5| 6| 5| 4| 5| 4| 7| 5| 3| 4| 5| 6| 6| 5| 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      |
   B6C3F1 MICE 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               |                                                                          |            |
                                           |                                                                          |            |
      Histiocytic Sarcoma                  |                                                                          |          2 |
      Lymphoma Malignant                   |                X     X                                                   |          4 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  M  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  45        |
      Histiocytic Sarcoma                  |                                                                          |          2 |
      Lymphoma Malignant                   |                X     X                       X                           |          5 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mediastinal                 | +  +  +  +  M  +  M  +  M  +  +  +  M  +  M  +  +  +  +  +  +  +  +  +  +|  36        |
      Histiocytic Sarcoma                  |                                                                          |          2 |
      Lymphoma Malignant                   |                X     X                       X                           |          6 |
                                            __________________________________________________________________________|____________|
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Histiocytic Sarcoma                  |                                                                          |          2 |
      Lymphoma Malignant                   |                X     X                       X                           |          6 |
                                            __________________________________________________________________________|____________|
   Thymus                                  | +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  44        |
      Histiocytic Sarcoma                  |                                                                          |          1 |
      Lymphoma Malignant                   |                X     X                       X                           |          4 |
 _____________________________________________________________________________________________________________________|            |
 INTEGUMENTARY SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Mammary Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Carcinoma                            |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Subcutaneous Tissue, Lymphoma        |                                                                          |            |
          Malignant                        |                                                                          |          1 |
      Subcutaneous Tissue, Sarcoma         |                         X                                      X         |          2 |
 _____________________________________________________________________________________________________________________|            |
 MUSCULOSKELETAL SYSTEM                    |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Skeletal Muscle                         |                +                                                         |   1        |
      Lymphoma Malignant                   |                X                                                         |          1 |
 _____________________________________________________________________________________________________________________|            |
 NERVOUS SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Lymphoma Malignant                   |                                                                          |          1 |
 _____________________________________________________________________________________________________________________|            |
 RESPIRATORY SYSTEM                        |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Alveolar/Bronchiolar Adenoma         | X                 X                                                      |          5 |
      Alveolar/Bronchiolar Adenoma,        |                                                                          |            |
          Multiple                         |                                                                          |          1 |
      Alveolar/Bronchiolar Carcinoma       |                                                                          |          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  16                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 6| 5| 7| 7| 7| 7| 7| 6| 5| 7| 7| 7| 7| 7| 7| 7| 7| 6| 7| 7| 7| 6| 7| 7| 7|            |
                             DAY ON TEST   | 6| 9| 3| 3| 3| 2| 2| 6| 9| 3| 3| 3| 3| 3| 3| 2| 3| 9| 3| 3| 3| 6| 3| 3| 3|            |
                                           | 4| 6| 5| 4| 5| 6| 0| 6| 3| 5| 6| 5| 4| 5| 4| 7| 5| 3| 4| 5| 6| 6| 5| 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      |
   B6C3F1 MICE 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|            |
 __________________________________________________________________________________________________________________________________ 
 RESPIRATORY SYSTEM - cont                 |                                                                          |            |
                                           |                                                                          |            |
      Histiocytic Sarcoma                  |                                                                          |          2 |
      Lymphoma Malignant                   |                X     X                       X                           |          4 |
                                            __________________________________________________________________________|____________|
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Lymphoma Malignant                   |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 SPECIAL SENSES SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Harderian Gland                         |                                     +           +                        |   2        |
      Adenoma                              |                                     X           X                        |          2 |
 _____________________________________________________________________________________________________________________|            |
 URINARY SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Histiocytic Sarcoma                  |                                                                          |          1 |
      Lymphoma Malignant                   |                X     X                       X                           |          4 |
                                            __________________________________________________________________________|____________|
   Urinary Bladder                         | +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  47        |
      Lymphoma Malignant                   |                X     X                                                   |          2 |
 __________________________________________________________________________________________________________________________________ 
 SYSTEMIC LESIONS                          |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Multiple Organs                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Histiocytic Sarcoma                  |                                                                          |          2 |
      Lymphoma Malignant                   |                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  17                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 7| 7| 7| 6| 7| 4| 7| 7| 6| 7| 7| 6| 7| 7| 7| 7| 7| 5| 0| 7| 5| 7| 7| 7|             
                             DAY ON TEST   | 3| 3| 3| 3| 7| 3| 9| 3| 3| 5| 3| 3| 6| 2| 3| 3| 3| 3| 0| 0| 3| 2| 0| 3| 3|             
                                           | 5| 5| 4| 5| 4| 5| 5| 5| 3| 9| 4| 6| 6| 0| 5| 5| 6| 4| 5| 9| 5| 4| 3| 5| 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|             
   B6C3F1 MICE 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                               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
                                            __________________________________________________________________________|             
   Gallbladder                             | +  +  +  +  M  +  A  M  A  +  M  +  +  M  +  +  +  +  +  +  M  +  A  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Colon                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Cecum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
      Lymphoma Malignant                   |                                                                          |             
                                            __________________________________________________________________________|             
   Intestine Small, Duodenum               | +  +  +  +  +  +  A  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
      Peyer's Patch, Lymphoma Malignant    |                                                                          |             
                                            __________________________________________________________________________|             
   Intestine Small, Jejunum                | +  +  +  +  +  +  A  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
      Hemangiosarcoma                      |                                                                X         |             
      Peyer's Patch, Lymphoma Malignant    |                                                                          |             
                                            __________________________________________________________________________|             
   Intestine Small, Ileum                  | +  +  +  +  +  +  A  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
      Peyer's Patch, Lymphoma Malignant    |       X                                                                  |             
                                            __________________________________________________________________________|             
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hemangiosarcoma                      |                                                                X         |             
      Hepatocellular Carcinoma             |          X           X  X  X        X  X     X     X              X     X|             
      Hepatocellular Adenoma               | X  X                    X  X                       X                    X|             
      Hepatocellular Adenoma, Multiple     |       X                                                                  |             
      Lymphoma Malignant                   |                                                                          |             
                                            __________________________________________________________________________|             
   Mesentery                               |                               +        +           +                     |             
      Hemangiosarcoma                      |                                                                          |             
                                            __________________________________________________________________________|             
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +|             
      Lymphoma Malignant                   |                                                                          |             
                                            __________________________________________________________________________|             
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Lymphoma Malignant                   |                                                                          |             
                                            __________________________________________________________________________|             
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
                                            __________________________________________________________________________|             
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
 _____________________________________________________________________________________________________________________|             
 CARDIOVASCULAR SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM                          |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
                                            __________________________________________________________________________|             
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
                                            __________________________________________________________________________|             
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +|             
                                            __________________________________________________________________________|             
   Parathyroid Gland                       | M  I  +  +  M  +  M  +  +  M  +  M  M  M  +  +  +  +  M  +  +  M  A  +  +|             
                                            __________________________________________________________________________|             
   Pituitary Gland                         | +  +  +  +  +  +  +  I  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
      Pars Distalis, Adenoma               |       X  X                 X              X                             X|             
                                            __________________________________________________________________________|             
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
      Follicular Cell, Carcinoma           |                X                                                         |             
 _____________________________________________________________________________________________________________________|             
 GENERAL BODY SYSTEM                       |                                                                          |             
                                           |                                                                          |             
    None                                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 GENITAL SYSTEM                            |                                                                          |             
 _____________________________________________________________________________________________________________________|             

                                                             Page  18                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 7| 7| 7| 6| 7| 4| 7| 7| 6| 7| 7| 6| 7| 7| 7| 7| 7| 5| 0| 7| 5| 7| 7| 7|             
                             DAY ON TEST   | 3| 3| 3| 3| 7| 3| 9| 3| 3| 5| 3| 3| 6| 2| 3| 3| 3| 3| 0| 0| 3| 2| 0| 3| 3|             
                                           | 5| 5| 4| 5| 4| 5| 5| 5| 3| 9| 4| 6| 6| 0| 5| 5| 6| 4| 5| 9| 5| 4| 3| 5| 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|             
   B6C3F1 MICE 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|             
 _____________________________________________________________________________________________________________________|             
 GENITAL SYSTEM - cont                     |                                                                          |             
                                           |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Clitoral Gland                          | +  M  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Ovary                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
      Cystadenoma                          |                                                                          |             
      Granulosa Cell Tumor Benign          |                                                             X            |             
      Luteoma                              |                X                                                         |             
      Teratoma Benign                      |                               X                                          |             
      Yolk Sac Carcinoma                   |                                                                          |             
      Periovarian Tissue, Lymphoma         |                                                                          |             
          Malignant                        |                                                                          |             
                                            __________________________________________________________________________|             
   Uterus                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
      Hemangioma                           |                                                                         X|             
      Lymphoma Malignant                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
                                            __________________________________________________________________________|             
   Lymph Node                              |                      +                                                   |             
      Lymphoma Malignant                   |                      X                                                   |             
      Iliac, Lymphoma Malignant            |                                                                          |             
      Renal, Lymphoma Malignant            |                                                                          |             
                                            __________________________________________________________________________|             
   Lymph Node, Bronchial                   | +  +  +  M  M  +  M  +  M  M  +  +  M  +  +  +  +  M  M  +  M  +  M  M  M|             
      Lymphoma Malignant                   |                      X                                                   |             
                                            __________________________________________________________________________|             
   Lymph Node, Mandibular                  | +  +  M  +  +  +  +  +  M  +  M  +  M  +  +  +  +  +  I  +  M  M  +  +  +|             
      Lymphoma Malignant                   |                      X                                                   |             
                                            __________________________________________________________________________|             
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
      Lymphoma Malignant                   |       X              X                                                   |             
                                            __________________________________________________________________________|             
   Lymph Node, Mediastinal                 | +  +  M  +  +  +  M  +  M  +  +  M  M  +  +  +  M  +  +  M  M  +  A  +  +|             
      Lymphoma Malignant                   |                      X                                                   |             
                                            __________________________________________________________________________|             
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +|             
      Lymphoma Malignant                   |       X                       X                                          |             
                                            __________________________________________________________________________|             
   Thymus                                  | +  +  +  +  +  +  +  +  M  +  M  +  +  M  +  +  +  M  +  +  +  +  A  +  +|             
      Lymphoma Malignant                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 INTEGUMENTARY SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Mammary Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Carcinoma                            |                                           X                              |             
                                            __________________________________________________________________________|             
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hemangiosarcoma                      |                                                                          |             
      Subcutaneous Tissue, Mast Cell Tumor |                                                                          |             
          Benign                           |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM                    |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Skeletal Muscle                         |                                                          +               |             
 _____________________________________________________________________________________________________________________|             

                                                             Page  19                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 7| 7| 7| 6| 7| 4| 7| 7| 6| 7| 7| 6| 7| 7| 7| 7| 7| 5| 0| 7| 5| 7| 7| 7|             
                             DAY ON TEST   | 3| 3| 3| 3| 7| 3| 9| 3| 3| 5| 3| 3| 6| 2| 3| 3| 3| 3| 0| 0| 3| 2| 0| 3| 3|             
                                           | 5| 5| 4| 5| 4| 5| 5| 5| 3| 9| 4| 6| 6| 0| 5| 5| 6| 4| 5| 9| 5| 4| 3| 5| 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|             
   B6C3F1 MICE 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             |                                                                          |             
                                           |                                                                          |             
      Sarcoma                              |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 NERVOUS SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 RESPIRATORY SYSTEM                        |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  I  +  +  +  +  A  +  +|             
                                            __________________________________________________________________________|             
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Alveolar/Bronchiolar Adenoma         |    X                                   X  X                              |             
      Alveolar/Bronchiolar Adenoma,        |                                                                          |             
          Multiple                         |                                  X                                       |             
      Alveolar/Bronchiolar Carcinoma       |                   X                                                      |             
      Hepatocellular Carcinoma, Metastatic,|                                                                          |             
           Liver                           |                         X           X                             X      |             
      Lymphoma Malignant                   |                                                                          |             
                                            __________________________________________________________________________|             
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
                                            __________________________________________________________________________|             
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
 _____________________________________________________________________________________________________________________|             
 SPECIAL SENSES SYSTEM                     |                                                                          |             
                                           |                                                                          |             
    None                                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Lymphoma Malignant                   |                                                                          |             
                                            __________________________________________________________________________|             
   Urinary Bladder                         | +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  I|             
 _____________________________________________________________________________________________________________________|             
 SYSTEMIC LESIONS                          |                                                                          |             
                                            __________________________________________________________________________|             
   Multiple Organs                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Lymphoma Malignant                   |       X              X        X                                          |             
 _____________________________________________________________________________________________________________________|             

                                                             Page  20                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 7| 7| 7| 6| 7| 7| 7| 7| 6| 7| 5| 6| 7| 7| 7| 7| 6| 5| 7| 7| 7| 6| 7| 7|            |
                             DAY ON TEST   | 3| 3| 3| 0| 6| 3| 3| 3| 3| 6| 3| 4| 2| 3| 3| 3| 3| 4| 6| 3| 3| 3| 4| 3| 3|            |
                                           | 6| 6| 6| 9| 7| 5| 6| 6| 6| 6| 5| 8| 2| 4| 6| 5| 5| 9| 9| 6| 6| 6| 0| 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      |
   B6C3F1 MICE 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                               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Gallbladder                             | +  M  +  +  M  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  A  +  +|  38        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Colon                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Cecum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|  48        |
      Lymphoma Malignant                   |                X                                                         |          1 |
                                            __________________________________________________________________________|____________|
   Intestine Small, Duodenum               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  47        |
      Peyer's Patch, Lymphoma Malignant    |                X                                   X                     |          2 |
                                            __________________________________________________________________________|____________|
   Intestine Small, Jejunum                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  47        |
      Hemangiosarcoma                      |                                                                          |          1 |
      Peyer's Patch, Lymphoma Malignant    |                                                    X                     |          1 |
                                            __________________________________________________________________________|____________|
   Intestine Small, Ileum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  47        |
      Peyer's Patch, Lymphoma Malignant    |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hemangiosarcoma                      |       X                             X                                    |          3 |
      Hepatocellular Carcinoma             |    X        X  X  X                    X                          X      |         16 |
      Hepatocellular Adenoma               |                            X  X     X  X           X                     |         11 |
      Hepatocellular Adenoma, Multiple     |                                                                      X   |          2 |
      Lymphoma Malignant                   |             X                                      X                     |          2 |
                                            __________________________________________________________________________|____________|
   Mesentery                               |                +        +           +        +                       +   |   8        |
      Hemangiosarcoma                      |                                     X                                    |          1 |
                                            __________________________________________________________________________|____________|
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Lymphoma Malignant                   |                                                    X                     |          1 |
                                            __________________________________________________________________________|____________|
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Lymphoma Malignant                   |             X                                                            |          1 |
                                            __________________________________________________________________________|____________|
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
 _____________________________________________________________________________________________________________________|            |
 CARDIOVASCULAR SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 ENDOCRINE SYSTEM                          |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Parathyroid Gland                       | +  +  +  +  +  +  +  M  M  +  +  +  M  M  M  M  +  M  M  +  M  M  +  +  M|  28        |
                                            __________________________________________________________________________|____________|
   Pituitary Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +|  47        |
      Pars Distalis, Adenoma               |                      X     X                                             |          7 |
                                            __________________________________________________________________________|____________|
   Thyroid 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  21                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 7| 7| 7| 6| 7| 7| 7| 7| 6| 7| 5| 6| 7| 7| 7| 7| 6| 5| 7| 7| 7| 6| 7| 7|            |
                             DAY ON TEST   | 3| 3| 3| 0| 6| 3| 3| 3| 3| 6| 3| 4| 2| 3| 3| 3| 3| 4| 6| 3| 3| 3| 4| 3| 3|            |
                                           | 6| 6| 6| 9| 7| 5| 6| 6| 6| 6| 5| 8| 2| 4| 6| 5| 5| 9| 9| 6| 6| 6| 0| 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      |
   B6C3F1 MICE 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                   |                                                                          |            |
                                           |                                                                          |            |
      Follicular Cell, Carcinoma           |                                                          X               |          2 |
 _____________________________________________________________________________________________________________________|            |
 GENERAL BODY SYSTEM                       |                                                                          |            |
                                           |                                                                          |            |
    None                                   |                                                                          |            |
 _____________________________________________________________________________________________________________________|            |
 GENITAL SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Clitoral Gland                          | +  +  +  +  +  +  M  M  M  +  +  M  +  M  +  +  +  +  +  +  +  +  +  +  +|  43        |
                                            __________________________________________________________________________|____________|
   Ovary                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Cystadenoma                          |                         X     X           X                              |          3 |
      Granulosa Cell Tumor Benign          |                                                                          |          1 |
      Luteoma                              |                                                                          |          1 |
      Teratoma Benign                      |                                                                          |          1 |
      Yolk Sac Carcinoma                   |       X                                                                  |          1 |
      Periovarian Tissue, Lymphoma         |                                                                          |            |
          Malignant                        |                X                                                         |          1 |
                                            __________________________________________________________________________|____________|
   Uterus                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Hemangioma                           |          X                                                               |          2 |
      Lymphoma Malignant                   |             X                                                            |          1 |
 _____________________________________________________________________________________________________________________|            |
 HEMATOPOIETIC SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Lymph Node                              |             +                                                  +         |   3        |
      Lymphoma Malignant                   |                                                                          |          1 |
      Iliac, Lymphoma Malignant            |             X                                                            |          1 |
      Renal, Lymphoma Malignant            |             X                                                            |          1 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Bronchial                   | M  M  M  M  +  M  +  +  +  +  +  M  M  +  +  +  +  M  M  +  +  +  M  M  +|  27        |
      Lymphoma Malignant                   |             X                                                            |          2 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mandibular                  | +  M  +  M  +  +  +  +  +  +  +  M  M  +  +  +  +  M  +  +  M  +  +  +  M|  36        |
      Lymphoma Malignant                   |             X                                                            |          2 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  M  +  +  +  +  M  +|  46        |
      Lymphoma Malignant                   |             X  X                                   X                     |          5 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mediastinal                 | M  +  M  M  +  +  M  M  M  M  +  M  M  +  +  M  +  +  +  M  M  M  +  +  +|  28        |
      Lymphoma Malignant                   |             X                                      X                     |          3 |
                                            __________________________________________________________________________|____________|
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Lymphoma Malignant                   |    X        X  X                                   X                     |          6 |
                                            __________________________________________________________________________|____________|
   Thymus                                  | +  +  +  M  M  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  M  +|  41        |
      Lymphoma Malignant                   |                                                    X                     |          1 |
 _____________________________________________________________________________________________________________________|            |
 INTEGUMENTARY 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  22                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 7| 7| 7| 6| 7| 7| 7| 7| 6| 7| 5| 6| 7| 7| 7| 7| 6| 5| 7| 7| 7| 6| 7| 7|            |
                             DAY ON TEST   | 3| 3| 3| 0| 6| 3| 3| 3| 3| 6| 3| 4| 2| 3| 3| 3| 3| 4| 6| 3| 3| 3| 4| 3| 3|            |
                                           | 6| 6| 6| 9| 7| 5| 6| 6| 6| 6| 5| 8| 2| 4| 6| 5| 5| 9| 9| 6| 6| 6| 0| 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      |
   B6C3F1 MICE 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|            |
 __________________________________________________________________________________________________________________________________ 
 INTEGUMENTARY SYSTEM - cont               |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Mammary Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Carcinoma                            |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hemangiosarcoma                      |                                              X                           |          1 |
      Subcutaneous Tissue, Mast Cell Tumor |                                                                          |            |
          Benign                           |                      X                                                   |          1 |
 _____________________________________________________________________________________________________________________|            |
 MUSCULOSKELETAL SYSTEM                    |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Skeletal Muscle                         |                      +                                                   |   2        |
      Sarcoma                              |                      X                                                   |          1 |
 _____________________________________________________________________________________________________________________|            |
 NERVOUS SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 RESPIRATORY SYSTEM                        |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  I  +  +|  47        |
                                            __________________________________________________________________________|____________|
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Alveolar/Bronchiolar Adenoma         | X        X     X                                   X           X         |          8 |
      Alveolar/Bronchiolar Adenoma,        |                                                                          |            |
          Multiple                         |                                                                          |          1 |
      Alveolar/Bronchiolar Carcinoma       |                                  X                    X                 X|          4 |
      Hepatocellular Carcinoma, Metastatic,|                                                                          |            |
           Liver                           |             X                                                     X      |          5 |
      Lymphoma Malignant                   |             X                                                            |          1 |
                                            __________________________________________________________________________|____________|
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
 _____________________________________________________________________________________________________________________|            |
 SPECIAL SENSES SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
    None                                   |                                                                          |            |
 _____________________________________________________________________________________________________________________|            |
 URINARY SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Lymphoma Malignant                   |             X                                      X                     |          2 |
                                            __________________________________________________________________________|____________|
   Urinary Bladder                         | +  +  +  +  +  +  +  +  +  I  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|  45        |
 __________________________________________________________________________________________________________________________________ 
 SYSTEMIC LESIONS                          |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Multiple Organs                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Lymphoma Malignant                   |    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  23                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 6| 5| 7| 7| 7| 3| 6| 7| 7| 6| 7| 4| 7| 7| 7| 7| 6| 7| 4| 7| 4| 7| 7| 7|             
                             DAY ON TEST   | 3| 8| 3| 0| 3| 3| 5| 0| 3| 3| 9| 3| 4| 3| 3| 3| 1| 8| 3| 6| 3| 8| 1| 3| 3|             
                                           | 6| 0| 9| 6| 6| 5| 6| 6| 5| 2| 2| 6| 3| 4| 5| 6| 2| 6| 5| 2| 5| 4| 9| 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|             
   B6C3F1 MICE 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                               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Gallbladder                             | +  +  +  +  +  +  +  +  +  M  +  +  A  +  +  +  A  M  +  +  +  +  +  +  +|             
      Lymphoma Malignant                   |                                                                          |             
                                            __________________________________________________________________________|             
   Intestine Large, Colon                  | +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Cecum                  | +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +|             
      Leiomyoma                            |          X                                                               |             
                                            __________________________________________________________________________|             
   Intestine Small, Duodenum               | +  +  +  +  +  +  +  +  +  A  A  +  A  +  +  +  A  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Jejunum                | +  +  +  +  +  +  +  +  +  A  A  +  A  +  +  +  A  +  +  +  +  +  +  +  +|             
      Peyer's Patch, Lymphoma Malignant    |          X                                                               |             
                                            __________________________________________________________________________|             
   Intestine Small, Ileum                  | +  +  +  +  +  +  +  +  +  A  A  +  A  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hepatocellular Carcinoma             |                            X                       X                     |             
      Hepatocellular Adenoma               |    X  X                 X              X                                 |             
      Hepatocellular Adenoma, Multiple     |                      X                                                   |             
      Histiocytic Sarcoma                  |                                                 X                        |             
      Lymphoma Malignant                   |          X                                                               |             
                                            __________________________________________________________________________|             
   Mesentery                               |                +  +                                   +                  |             
      Hemangioma                           |                                                                          |             
      Lymphoma Malignant                   |                   X                                                      |             
                                            __________________________________________________________________________|             
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Lymphoma Malignant                   |                                                                          |             
                                            __________________________________________________________________________|             
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Lymphoma Malignant                   |                                                                          |             
                                            __________________________________________________________________________|             
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Squamous Cell Papilloma              |                                                                          |             
      Serosa, Lymphoma Malignant           |                                                                          |             
                                            __________________________________________________________________________|             
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 CARDIOVASCULAR SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM                          |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Capsule, Lymphoma Malignant          |                                                                          |             
                                            __________________________________________________________________________|             
   Adrenal Medulla                         | +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Adenoma                              |                                                                          |             
                                            __________________________________________________________________________|             
   Parathyroid Gland                       | M  +  +  +  M  +  +  M  M  +  +  I  +  +  M  M  M  I  M  M  +  +  +  M  M|             
                                            __________________________________________________________________________|             
   Pituitary Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  I  +  +  +  +  +  +  +  +  +  +  +  +|             
      Pars Distalis, Adenoma               |                                        X           X              X  X   |             
                                            __________________________________________________________________________|             
   Thyroid Gland                           | +  +  +  +  +  +  +  I  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Follicular Cell, Adenoma             |                                              X     X                 X   |             
 _____________________________________________________________________________________________________________________|             
 GENERAL BODY SYSTEM                       |                                                                          |             
                                           |                                                                          |             
    None                                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             

                                                             Page  24                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 6| 5| 7| 7| 7| 3| 6| 7| 7| 6| 7| 4| 7| 7| 7| 7| 6| 7| 4| 7| 4| 7| 7| 7|             
                             DAY ON TEST   | 3| 8| 3| 0| 3| 3| 5| 0| 3| 3| 9| 3| 4| 3| 3| 3| 1| 8| 3| 6| 3| 8| 1| 3| 3|             
                                           | 6| 0| 9| 6| 6| 5| 6| 6| 5| 2| 2| 6| 3| 4| 5| 6| 2| 6| 5| 2| 5| 4| 9| 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|             
   B6C3F1 MICE 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|             
 _____________________________________________________________________________________________________________________|             
 GENITAL SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Clitoral Gland                          | +  M  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  M  M  +  M  +  +  M  +|             
                                            __________________________________________________________________________|             
   Ovary                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  I  +  +  +  +  +  +  +  +|             
      Cystadenoma                          |                                                                          |             
      Histiocytic Sarcoma                  |                                                                          |             
      Lymphoma Malignant                   |          X                                                               |             
                                            __________________________________________________________________________|             
   Uterus                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Histiocytic Sarcoma                  |                                                                          |             
      Leiomyosarcoma                       |                                                                          |             
      Lymphoma Malignant                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Histiocytic Sarcoma                  |                                                 X                        |             
      Lymphoma Malignant                   |                                                                          |             
                                            __________________________________________________________________________|             
   Lymph Node                              |          +                                                               |             
      Lymphoma Malignant                   |                                                                          |             
      Iliac, Lymphoma Malignant            |                                                                          |             
      Lumbar, Lymphoma Malignant           |          X                                                               |             
      Pancreatic, Lymphoma Malignant       |                                                                          |             
      Renal, Lymphoma Malignant            |          X                                                               |             
                                            __________________________________________________________________________|             
   Lymph Node, Bronchial                   | +  +  M  M  +  +  +  M  +  M  M  +  +  +  +  +  +  M  +  M  +  +  M  +  +|             
      Histiocytic Sarcoma                  |                                                 X                        |             
      Lymphoma Malignant                   |                                                                          |             
                                            __________________________________________________________________________|             
   Lymph Node, Mandibular                  | M  +  +  +  I  +  M  M  M  +  +  +  +  M  M  M  +  M  +  +  +  +  +  +  +|             
      Histiocytic Sarcoma                  |                                                 X                        |             
      Lymphoma Malignant                   |          X                                                               |             
                                            __________________________________________________________________________|             
   Lymph Node, Mesenteric                  | +  +  M  +  +  +  +  +  +  I  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +|             
      Histiocytic Sarcoma                  |                                                 X                        |             
      Lymphoma Malignant                   |          X        X                                                      |             
                                            __________________________________________________________________________|             
   Lymph Node, Mediastinal                 | M  +  +  +  M  +  +  +  M  M  +  +  +  +  M  M  +  +  M  +  M  +  +  +  M|             
      Alveolar/Bronchiolar Carcinoma,      |                                                                          |             
          Metastatic, Lung                 |                                                                          |             
      Histiocytic Sarcoma                  |                                                 X                        |             
      Lymphoma Malignant                   |          X                                                               |             
                                            __________________________________________________________________________|             
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Histiocytic Sarcoma                  |                                                 X                        |             
      Lymphoma Malignant                   |                                                                          |             
                                            __________________________________________________________________________|             
   Thymus                                  | +  +  +  +  +  +  +  M  +  M  +  +  M  +  +  +  +  M  +  +  +  +  +  +  +|             
      Lymphoma Malignant                   |          X                                                               |             
 _____________________________________________________________________________________________________________________|             
 INTEGUMENTARY SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Mammary Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Adenoma                              |                                                                          |             
      Carcinoma                            |                               X                                          |             
 _____________________________________________________________________________________________________________________|             

                                                             Page  25                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 6| 5| 7| 7| 7| 3| 6| 7| 7| 6| 7| 4| 7| 7| 7| 7| 6| 7| 4| 7| 4| 7| 7| 7|             
                             DAY ON TEST   | 3| 8| 3| 0| 3| 3| 5| 0| 3| 3| 9| 3| 4| 3| 3| 3| 1| 8| 3| 6| 3| 8| 1| 3| 3|             
                                           | 6| 0| 9| 6| 6| 5| 6| 6| 5| 2| 2| 6| 3| 4| 5| 6| 2| 6| 5| 2| 5| 4| 9| 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|             
   B6C3F1 MICE 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               |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Histiocytic Sarcoma                  |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM                    |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Skeletal Muscle                         |                                  +                                       |             
      Sarcoma                              |                                  X                                       |             
 _____________________________________________________________________________________________________________________|             
 NERVOUS SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Spinal Cord                             |       +                                                                  |             
 _____________________________________________________________________________________________________________________|             
 RESPIRATORY SYSTEM                        |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Alveolar/Bronchiolar Adenoma         | X        X     X        X                                            X   |             
      Alveolar/Bronchiolar Adenoma,        |                                                                          |             
          Multiple                         |                                                 X                        |             
      Alveolar/Bronchiolar Carcinoma       |                X                       X                          X      |             
      Hepatocellular Carcinoma, Metastatic,|                                                                          |             
           Liver                           |                                                    X                     |             
      Histiocytic Sarcoma                  |                                                 X                        |             
      Lymphoma Malignant                   |                                                                          |             
                                            __________________________________________________________________________|             
   Nose                                    | +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 SPECIAL SENSES SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Harderian Gland                         |                                                                      +   |             
      Adenoma                              |                                                                      X   |             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Histiocytic Sarcoma                  |                                                 X                        |             
      Lymphoma Malignant                   |                                                                          |             
                                            __________________________________________________________________________|             
   Urinary Bladder                         | +  +  +  +  +  +  +  +  +  A  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +|             
      Lymphoma Malignant                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 SYSTEMIC LESIONS                          |                                                                          |             
                                            __________________________________________________________________________|             
   Multiple Organs                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Histiocytic Sarcoma                  |                                                 X                        |             
      Lymphoma Malignant                   |          X        X                                                      |             
 _____________________________________________________________________________________________________________________|             

                                                             Page  26                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 5| 6| 7| 7| 7| 4| 7| 6| 7| 7| 7| 7| 7| 7| 6| 7| 7| 7| 7| 7| 6| 7| 7| 6| 7|            |
                             DAY ON TEST   | 3| 0| 3| 3| 3| 2| 3| 7| 3| 3| 3| 3| 3| 3| 1| 3| 2| 1| 3| 3| 3| 3| 3| 6| 3|            |
                                           | 6| 9| 6| 6| 4| 9| 5| 5| 6| 5| 5| 5| 4| 6| 1| 6| 6| 7| 6| 6| 9| 6| 6| 7| 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      |
   B6C3F1 MICE 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        |
                                            __________________________________________________________________________|____________|
   Gallbladder                             | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  M  +|  43        |
      Lymphoma Malignant                   |                                                 X                        |          1 |
                                            __________________________________________________________________________|____________|
   Intestine Large, Colon                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  47        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Cecum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  47        |
      Leiomyoma                            |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Intestine Small, Duodenum               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  45        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Jejunum                | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  44        |
      Peyer's Patch, Lymphoma Malignant    |                                                          X               |          2 |
                                            __________________________________________________________________________|____________|
   Intestine Small, Ileum                  | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  45        |
                                            __________________________________________________________________________|____________|
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  49        |
      Hepatocellular Carcinoma             |                                                                      X  X|          4 |
      Hepatocellular Adenoma               |                                     X     X  X        X        X         |          9 |
      Hepatocellular Adenoma, Multiple     |       X                 X                                                |          3 |
      Histiocytic Sarcoma                  |                                                                      X   |          2 |
      Lymphoma Malignant                   |    X                                            X                        |          3 |
                                            __________________________________________________________________________|____________|
   Mesentery                               |                            +                 +        +                 +|   7        |
      Hemangioma                           |                                                                         X|          1 |
      Lymphoma Malignant                   |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  49        |
      Lymphoma Malignant                   |                                                 X        X               |          2 |
                                            __________________________________________________________________________|____________|
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Lymphoma Malignant                   |                                                 X                        |          1 |
                                            __________________________________________________________________________|____________|
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Squamous Cell Papilloma              |       X                                                                  |          1 |
      Serosa, Lymphoma Malignant           |                                                 X                        |          1 |
                                            __________________________________________________________________________|____________|
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 CARDIOVASCULAR SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 ENDOCRINE SYSTEM                          |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Capsule, Lymphoma Malignant          |                                                 X                        |          1 |
                                            __________________________________________________________________________|____________|
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  49        |
      Adenoma                              |       X                                                                  |          1 |
                                            __________________________________________________________________________|____________|
   Parathyroid Gland                       | M  +  +  +  I  +  M  M  +  M  +  +  M  +  +  +  +  +  M  +  I  +  M  M  M|  26        |
 __________________________________________________________________________________________________________________________________ 

                         * : 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: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 5| 6| 7| 7| 7| 4| 7| 6| 7| 7| 7| 7| 7| 7| 6| 7| 7| 7| 7| 7| 6| 7| 7| 6| 7|            |
                             DAY ON TEST   | 3| 0| 3| 3| 3| 2| 3| 7| 3| 3| 3| 3| 3| 3| 1| 3| 2| 1| 3| 3| 3| 3| 3| 6| 3|            |
                                           | 6| 9| 6| 6| 4| 9| 5| 5| 6| 5| 5| 5| 4| 6| 1| 6| 6| 7| 6| 6| 9| 6| 6| 7| 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      |
   B6C3F1 MICE 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                   |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Pituitary Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  48        |
      Pars Distalis, Adenoma               |                      X              X  X              X                  |          8 |
                                            __________________________________________________________________________|____________|
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Follicular Cell, Adenoma             |                                     X        X                           |          5 |
 _____________________________________________________________________________________________________________________|            |
 GENERAL BODY SYSTEM                       |                                                                          |            |
                                           |                                                                          |            |
    None                                   |                                                                          |            |
 _____________________________________________________________________________________________________________________|            |
 GENITAL SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Clitoral Gland                          | +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  M  +  +  +  +  +  +  M  +  M|  40        |
                                            __________________________________________________________________________|____________|
   Ovary                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  48        |
      Cystadenoma                          |                               X     X                             X      |          3 |
      Histiocytic Sarcoma                  |                                                             X            |          1 |
      Lymphoma Malignant                   |    X                                            X                        |          3 |
                                            __________________________________________________________________________|____________|
   Uterus                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  49        |
      Histiocytic Sarcoma                  |                                                             X            |          1 |
      Leiomyosarcoma                       |                                                                         X|          1 |
      Lymphoma Malignant                   |                                                 X                        |          1 |
 _____________________________________________________________________________________________________________________|            |
 HEMATOPOIETIC SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Histiocytic Sarcoma                  |                                                             X            |          2 |
      Lymphoma Malignant                   |                                                 X                        |          1 |
                                            __________________________________________________________________________|____________|
   Lymph Node                              |    +                                            +        +               |   4        |
      Lymphoma Malignant                   |                                                          X               |          1 |
      Iliac, Lymphoma Malignant            |                                                 X                        |          1 |
      Lumbar, Lymphoma Malignant           |                                                          X               |          2 |
      Pancreatic, Lymphoma Malignant       |    X                                                                     |          1 |
      Renal, Lymphoma Malignant            |                                                 X                        |          2 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Bronchial                   | +  +  +  +  +  M  +  M  +  +  +  +  +  +  M  +  +  M  +  M  M  +  +  M  +|  35        |
      Histiocytic Sarcoma                  |                                                                          |          1 |
      Lymphoma Malignant                   |    X                                            X                        |          2 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mandibular                  | +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  M  M  +  +  +  M  +  +  +  M|  36        |
      Histiocytic Sarcoma                  |                                                                          |          1 |
      Lymphoma Malignant                   |    X                                                     X               |          3 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  A  +  +  M  +  +  +  +|  44        |
      Histiocytic Sarcoma                  |                                                                          |          1 |
      Lymphoma Malignant                   |    X                                            X        X               |          5 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mediastinal                 | +  +  +  +  M  +  +  +  +  +  +  M  M  M  M  M  +  +  +  +  M  +  +  +  +|  34        |
 __________________________________________________________________________________________________________________________________ 

                         * : 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: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 5| 6| 7| 7| 7| 4| 7| 6| 7| 7| 7| 7| 7| 7| 6| 7| 7| 7| 7| 7| 6| 7| 7| 6| 7|            |
                             DAY ON TEST   | 3| 0| 3| 3| 3| 2| 3| 7| 3| 3| 3| 3| 3| 3| 1| 3| 2| 1| 3| 3| 3| 3| 3| 6| 3|            |
                                           | 6| 9| 6| 6| 4| 9| 5| 5| 6| 5| 5| 5| 4| 6| 1| 6| 6| 7| 6| 6| 9| 6| 6| 7| 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      |
   B6C3F1 MICE 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               |                                                                          |            |
                                           |                                                                          |            |
      Alveolar/Bronchiolar Carcinoma,      |                                                                          |            |
          Metastatic, Lung                 |                                                    X                     |          1 |
      Histiocytic Sarcoma                  |                                                                          |          1 |
      Lymphoma Malignant                   |    X                                            X        X               |          4 |
                                            __________________________________________________________________________|____________|
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  49        |
      Histiocytic Sarcoma                  |                                                                          |          1 |
      Lymphoma Malignant                   |    X                                            X        X               |          3 |
                                            __________________________________________________________________________|____________|
   Thymus                                  | +  M  +  +  +  M  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  M  +|  41        |
      Lymphoma Malignant                   |                                                 X                        |          2 |
 _____________________________________________________________________________________________________________________|            |
 INTEGUMENTARY SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Mammary Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Adenoma                              |                                                       X                  |          1 |
      Carcinoma                            |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Histiocytic Sarcoma                  |                                                                      X   |          1 |
 _____________________________________________________________________________________________________________________|            |
 MUSCULOSKELETAL SYSTEM                    |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Skeletal Muscle                         |                                                                          |   1        |
      Sarcoma                              |                                                                          |          1 |
 _____________________________________________________________________________________________________________________|            |
 NERVOUS SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Spinal Cord                             |                                                                          |   1        |
 _____________________________________________________________________________________________________________________|            |
 RESPIRATORY SYSTEM                        |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Alveolar/Bronchiolar Adenoma         |          X                                   X           X               |          8 |
      Alveolar/Bronchiolar Adenoma,        |                                                                          |            |
          Multiple                         |                                        X                                 |          2 |
      Alveolar/Bronchiolar Carcinoma       | X  X                 X     X     X                 X                     |          9 |
      Hepatocellular Carcinoma, Metastatic,|                                                                          |            |
           Liver                           |                                                                      X   |          2 |
      Histiocytic Sarcoma                  |                                                                          |          1 |
      Lymphoma Malignant                   |                                                 X                        |          1 |
                                            __________________________________________________________________________|____________|
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  48        |
                                            __________________________________________________________________________|____________|
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  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  29                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 5| 6| 7| 7| 7| 4| 7| 6| 7| 7| 7| 7| 7| 7| 6| 7| 7| 7| 7| 7| 6| 7| 7| 6| 7|            |
                             DAY ON TEST   | 3| 0| 3| 3| 3| 2| 3| 7| 3| 3| 3| 3| 3| 3| 1| 3| 2| 1| 3| 3| 3| 3| 3| 6| 3|            |
                                           | 6| 9| 6| 6| 4| 9| 5| 5| 6| 5| 5| 5| 4| 6| 1| 6| 6| 7| 6| 6| 9| 6| 6| 7| 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      |
   B6C3F1 MICE 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                 |                                                                          |            |
                                           |                                                                          |            |
 _____________________________________________________________________________________________________________________|            |
 SPECIAL SENSES SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Harderian Gland                         |                                                                          |   1        |
      Adenoma                              |                                                                          |          1 |
 _____________________________________________________________________________________________________________________|            |
 URINARY SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Histiocytic Sarcoma                  |                                                                          |          1 |
      Lymphoma Malignant                   |    X                                            X                        |          2 |
                                            __________________________________________________________________________|____________|
   Urinary Bladder                         | I  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  46        |
      Lymphoma Malignant                   |                                                 X                        |          1 |
 __________________________________________________________________________________________________________________________________ 
 SYSTEMIC LESIONS                          |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Multiple Organs                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Histiocytic Sarcoma                  |                                                             X        X   |          3 |
      Lymphoma Malignant                   |    X                                            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  30                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 6| 7| 7| 6| 6| 7| 4| 7| 5| 6| 7| 6| 6| 7| 4| 5| 7| 7| 5| 7| 7| 7| 7| 7| 6|             
                             DAY ON TEST   | 5| 3| 3| 0| 8| 3| 7| 3| 7| 0| 3| 8| 5| 3| 4| 4| 3| 3| 4| 3| 3| 0| 3| 3| 8|             
                                           | 2| 4| 4| 0| 0| 4| 0| 3| 5| 0| 3| 6| 1| 3| 9| 1| 4| 3| 1| 3| 3| 8| 3| 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|             
   B6C3F1 MICE 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                               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Gallbladder                             | +  +  M  +  +  M  +  +  M  +  +  +  A  +  +  A  +  +  +  +  +  +  +  +  M|             
                                            __________________________________________________________________________|             
   Intestine Large, Colon                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Cecum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  A|             
      Lymphoma Malignant                   |                                                                          |             
                                            __________________________________________________________________________|             
   Intestine Small, Duodenum               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Jejunum                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Ileum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +|             
      Lymphoma Malignant                   |                                                                          |             
                                            __________________________________________________________________________|             
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hemangiosarcoma                      |                      X                                                   |             
      Hepatoblastoma                       | X                             X                                          |             
      Hepatocellular Carcinoma             |             X           X  X                 X                 X        X|             
      Hepatocellular Carcinoma, Multiple   |       X        X                 X              X     X  X           X   |             
      Hepatocellular Adenoma               |    X                                   X        X           X        X   |             
      Hepatocellular Adenoma, Multiple     |          X  X     X           X                          X        X      |             
      Hepatocholangiocarcinoma             |                                              X                           |             
      Histiocytic Sarcoma                  |                                                                          |             
                                            __________________________________________________________________________|             
   Mesentery                               |                                              +  +              +         |             
      Hepatocholangiocarcinoma, Metastatic,|                                                                          |             
           Liver                           |                                              X                           |             
                                            __________________________________________________________________________|             
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +|             
      Histiocytic Sarcoma                  |                                                                          |             
                                            __________________________________________________________________________|             
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +     +  +  +     +     +  +|             
                                            __________________________________________________________________________|             
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Histiocytic Sarcoma                  |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 CARDIOVASCULAR SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM                          |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hepatocholangiocarcinoma, Metastatic,|                                                                          |             
           Liver                           |                                              X                           |             
                                            __________________________________________________________________________|             
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +|             
      Hepatocholangiocarcinoma, Metastatic,|                                                                          |             
           Liver                           |                                              X                           |             
      Pheochromocytoma Benign              |                                                          X               |             
                                            __________________________________________________________________________|             
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Parathyroid Gland                       | +  M  M  +  M  +  I  M  M  M  M  M  +  +  M  M  +  M  M  M  M  M  +  +  +|             
                                            __________________________________________________________________________|             
   Pituitary Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             

                                                             Page  31                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 6| 7| 7| 6| 6| 7| 4| 7| 5| 6| 7| 6| 6| 7| 4| 5| 7| 7| 5| 7| 7| 7| 7| 7| 6|             
                             DAY ON TEST   | 5| 3| 3| 0| 8| 3| 7| 3| 7| 0| 3| 8| 5| 3| 4| 4| 3| 3| 4| 3| 3| 0| 3| 3| 8|             
                                           | 2| 4| 4| 0| 0| 4| 0| 3| 5| 0| 3| 6| 1| 3| 9| 1| 4| 3| 1| 3| 3| 8| 3| 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|             
   B6C3F1 MICE 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                   |                                                                          |             
                                           |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 GENERAL BODY SYSTEM                       |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Peritoneum                              |                                              +                           |             
      Hepatocholangiocarcinoma, Metastatic,|                                                                          |             
           Liver                           |                                              X                           |             
                                            __________________________________________________________________________|             
   Tissue NOS                              |                                                                          |             
      Hemangioma                           |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 GENITAL SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Epididymis                              | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Penis                                   |                            +                                             |             
                                            __________________________________________________________________________|             
   Preputial Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Prostate                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Seminal Vesicle                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Testes                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Lymph Node                              |                                                                          |             
      Renal, Histiocytic Sarcoma           |                                                                          |             
                                            __________________________________________________________________________|             
   Lymph Node, Bronchial                   | +  M  M  +  M  M  +  I  M  M  M  M  +  M  +  M  M  M  M  +  +  +  +  M  M|             
      Histiocytic Sarcoma                  |                                                                          |             
      Lymphoma Malignant                   |                                                                          |             
                                            __________________________________________________________________________|             
   Lymph Node, Mandibular                  | +  M  M  +  +  +  M  +  M  +  +  +  M  +  +  M  M  +  +  +  +  M  M  +  M|             
                                            __________________________________________________________________________|             
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hepatoblastoma, Metastatic, Liver    | X                                                                        |             
      Histiocytic Sarcoma                  |                                                                          |             
      Lymphoma Malignant                   |                                                                          |             
                                            __________________________________________________________________________|             
   Lymph Node, Mediastinal                 | +  M  +  M  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +|             
      Hepatocellular Carcinoma, Metastatic,|                                                                          |             
           Liver                           |                                                                          |             
      Hepatocholangiocarcinoma, Metastatic,|                                                                          |             
           Liver                           |                                              X                           |             
      Histiocytic Sarcoma                  |                                                                          |             
      Lymphoma Malignant                   |                                                                          |             
                                            __________________________________________________________________________|             
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hemangiosarcoma                      |                                     X                                    |             
      Histiocytic Sarcoma                  |                                                                          |             
                                            __________________________________________________________________________|             
   Thymus                                  | +  M  +  +  I  I  +  +  M  +  M  M  +  +  M  +  M  M  M  +  +  +  +  M  M|             
 _____________________________________________________________________________________________________________________|             
 INTEGUMENTARY SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Mammary Gland                           | M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M|             
                                            __________________________________________________________________________|             
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hemangioma                           |                               X                                          |             
 _____________________________________________________________________________________________________________________|             

                                                             Page  32                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 6| 7| 7| 6| 6| 7| 4| 7| 5| 6| 7| 6| 6| 7| 4| 5| 7| 7| 5| 7| 7| 7| 7| 7| 6|             
                             DAY ON TEST   | 5| 3| 3| 0| 8| 3| 7| 3| 7| 0| 3| 8| 5| 3| 4| 4| 3| 3| 4| 3| 3| 0| 3| 3| 8|             
                                           | 2| 4| 4| 0| 0| 4| 0| 3| 5| 0| 3| 6| 1| 3| 9| 1| 4| 3| 1| 3| 3| 8| 3| 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|             
   B6C3F1 MICE 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|             
 _____________________________________________________________________________________________________________________|             
 INTEGUMENTARY SYSTEM - cont               |                                                                          |             
                                           |                                                                          |             
      Hemangiosarcoma                      |                                     X                                    |             
      Subcutaneous Tissue, Sarcoma         |                         X                                                |             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM                    |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Skeletal Muscle                         |                                              +                           |             
      Hepatocholangiocarcinoma, Metastatic,|                                                                          |             
           Liver                           |                                              X                           |             
 _____________________________________________________________________________________________________________________|             
 NERVOUS SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 RESPIRATORY SYSTEM                        |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Alveolar/Bronchiolar Adenoma         |          X                                         X           X        X|             
      Alveolar/Bronchiolar Carcinoma       |                                           X                              |             
      Alveolar/Bronchiolar Carcinoma,      |                                                                          |             
          Multiple                         |          X                                                               |             
      Hepatoblastoma, Metastatic, Liver    | X                                                                        |             
      Hepatocellular Carcinoma, Metastatic,|                                                                          |             
           Liver                           |                X        X                                                |             
      Histiocytic Sarcoma                  |                                                                          |             
                                            __________________________________________________________________________|             
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 SPECIAL SENSES SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Eye                                     |                            +                                             |             
                                            __________________________________________________________________________|             
   Harderian Gland                         |                            +                                             |             
      Adenoma                              |                            X                                             |             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Urinary Bladder                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 SYSTEMIC LESIONS                          |                                                                          |             
                                            __________________________________________________________________________|             
   Multiple Organs                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Histiocytic Sarcoma                  |                                                                          |             
      Lymphoma Malignant                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             

                                                             Page  33                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 6| 6| 6| 5| 7| 7| 6| 4| 7| 7| 7| 7| 6| 7| 7| 7| 5| 5| 4| 7| 7| 5| 6| 7| 6|            |
                             DAY ON TEST   | 7| 4| 4| 5| 3| 3| 5| 8| 3| 3| 1| 3| 8| 3| 2| 3| 1| 3| 8| 3| 3| 7| 4| 3| 1|            |
                                           | 6| 0| 9| 5| 3| 4| 2| 2| 4| 3| 1| 4| 6| 4| 5| 3| 6| 3| 6| 3| 4| 9| 3| 4| 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      |
   B6C3F1 MICE 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                               | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Gallbladder                             | +  +  +  +  +  +  M  A  +  +  +  +  +  +  M  +  +  A  A  +  +  M  A  +  +|  37        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Colon                  | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Cecum                  | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  A  +  +  +  A  +  +|  45        |
      Lymphoma Malignant                   | X                                                                        |          1 |
                                            __________________________________________________________________________|____________|
   Intestine Small, Duodenum               | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  A  A  +  +  +  A  +  +|  45        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Jejunum                | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  A  A  +  +  +  A  +  +|  45        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Ileum                  | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  A  A  +  +  +  A  +  +|  45        |
      Lymphoma Malignant                   | X                                                                        |          1 |
                                            __________________________________________________________________________|____________|
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hemangiosarcoma                      |             X                                                            |          2 |
      Hepatoblastoma                       |                                                    X           X         |          4 |
      Hepatocellular Carcinoma             |    X     X  X        X           X  X        X  X                 X  X   |         16 |
      Hepatocellular Carcinoma, Multiple   |                                                                          |          7 |
      Hepatocellular Adenoma               |                X        X        X  X  X  X           X        X     X   |         14 |
      Hepatocellular Adenoma, Multiple     |       X                    X                                             |          8 |
      Hepatocholangiocarcinoma             |                                                                          |          1 |
      Histiocytic Sarcoma                  |                               X                                          |          1 |
                                            __________________________________________________________________________|____________|
   Mesentery                               |                                                                          |   3        |
      Hepatocholangiocarcinoma, Metastatic,|                                                                          |            |
           Liver                           |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Pancreas                                | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
      Histiocytic Sarcoma                  |                               X                                          |          1 |
                                            __________________________________________________________________________|____________|
   Salivary Glands                         | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  46        |
                                            __________________________________________________________________________|____________|
   Stomach, Forestomach                    | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Stomach, Glandular                      | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +|  48        |
      Histiocytic Sarcoma                  |                               X                                          |          1 |
 _____________________________________________________________________________________________________________________|            |
 CARDIOVASCULAR SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 ENDOCRINE SYSTEM                          |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Adrenal Cortex                          | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Hepatocholangiocarcinoma, Metastatic,|                                                                          |            |
           Liver                           |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Adrenal Medulla                         | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
      Hepatocholangiocarcinoma, Metastatic,|                                                                          |            |
           Liver                           |                                                                          |          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  34                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 6| 6| 6| 5| 7| 7| 6| 4| 7| 7| 7| 7| 6| 7| 7| 7| 5| 5| 4| 7| 7| 5| 6| 7| 6|            |
                             DAY ON TEST   | 7| 4| 4| 5| 3| 3| 5| 8| 3| 3| 1| 3| 8| 3| 2| 3| 1| 3| 8| 3| 3| 7| 4| 3| 1|            |
                                           | 6| 0| 9| 5| 3| 4| 2| 2| 4| 3| 1| 4| 6| 4| 5| 3| 6| 3| 6| 3| 4| 9| 3| 4| 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      |
   B6C3F1 MICE 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                   |                                                                          |            |
                                           |                                                                          |            |
      Pheochromocytoma Benign              |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Islets, Pancreatic                      | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
                                            __________________________________________________________________________|____________|
   Parathyroid Gland                       | +  M  M  M  M  +  M  A  M  M  M  +  +  +  M  +  M  I  M  +  M  M  +  +  +|  19        |
                                            __________________________________________________________________________|____________|
   Pituitary Gland                         | +  M  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
                                            __________________________________________________________________________|____________|
   Thyroid Gland                           | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
 _____________________________________________________________________________________________________________________|            |
 GENERAL BODY SYSTEM                       |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Peritoneum                              |                                                                          |   1        |
      Hepatocholangiocarcinoma, Metastatic,|                                                                          |            |
           Liver                           |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Tissue NOS                              |                                                          +               |   1        |
      Hemangioma                           |                                                          X               |          1 |
 _____________________________________________________________________________________________________________________|            |
 GENITAL SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Epididymis                              | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Penis                                   |                                                                          |   1        |
                                            __________________________________________________________________________|____________|
   Preputial Gland                         | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Prostate                                | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  I  +  +  A  +  +|  46        |
                                            __________________________________________________________________________|____________|
   Seminal Vesicle                         | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
                                            __________________________________________________________________________|____________|
   Testes                                  | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
 _____________________________________________________________________________________________________________________|            |
 HEMATOPOIETIC SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone Marrow                             | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Lymph Node                              |                               +                                          |   1        |
      Renal, Histiocytic Sarcoma           |                               X                                          |          1 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Bronchial                   | +  +  M  M  M  +  M  M  M  +  +  +  M  +  M  I  M  +  +  +  +  +  M  M  I|  21        |
      Histiocytic Sarcoma                  |                               X                                          |          1 |
      Lymphoma Malignant                   | X                                                                        |          1 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mandibular                  | M  M  M  M  M  M  M  A  M  +  M  +  +  +  +  M  M  M  M  M  M  M  +  +  M|  22        |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Hepatoblastoma, Metastatic, Liver    |                                                                          |          1 |
      Histiocytic Sarcoma                  |                               X                                          |          1 |
      Lymphoma Malignant                   | X                                                                        |          1 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mediastinal                 | +  +  +  +  +  +  +  A  +  +  +  +  +  +  M  +  +  +  M  +  +  +  +  +  +|  43        |
      Hepatocellular Carcinoma, Metastatic,|                                                                          |            |
           Liver                           |                                                 X                        |          1 |
      Hepatocholangiocarcinoma, Metastatic,|                                                                          |            |
           Liver                           |                                                                          |          1 |
      Histiocytic Sarcoma                  |                               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  35                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 6| 6| 6| 5| 7| 7| 6| 4| 7| 7| 7| 7| 6| 7| 7| 7| 5| 5| 4| 7| 7| 5| 6| 7| 6|            |
                             DAY ON TEST   | 7| 4| 4| 5| 3| 3| 5| 8| 3| 3| 1| 3| 8| 3| 2| 3| 1| 3| 8| 3| 3| 7| 4| 3| 1|            |
                                           | 6| 0| 9| 5| 3| 4| 2| 2| 4| 3| 1| 4| 6| 4| 5| 3| 6| 3| 6| 3| 4| 9| 3| 4| 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      |
   B6C3F1 MICE 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               |                                                                          |            |
                                           |                                                                          |            |
      Lymphoma Malignant                   | X                                                                        |          1 |
                                            __________________________________________________________________________|____________|
   Spleen                                  | +  +  +  +  +  +  +  A  +  +  +  +  +  +  M  +  +  +  A  +  +  +  +  +  +|  47        |
      Hemangiosarcoma                      |                                                                          |          1 |
      Histiocytic Sarcoma                  |                               X                                          |          1 |
                                            __________________________________________________________________________|____________|
   Thymus                                  | M  +  M  +  M  +  +  A  +  +  M  +  M  M  +  I  M  +  +  +  +  +  M  +  +|  28        |
 _____________________________________________________________________________________________________________________|            |
 INTEGUMENTARY SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Mammary Gland                           | M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M|            |
                                            __________________________________________________________________________|____________|
   Skin                                    | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Hemangioma                           |                                                                          |          1 |
      Hemangiosarcoma                      |                                                                          |          1 |
      Subcutaneous Tissue, Sarcoma         |                                                                          |          1 |
 _____________________________________________________________________________________________________________________|            |
 MUSCULOSKELETAL SYSTEM                    |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Skeletal Muscle                         |                                                                          |   1        |
      Hepatocholangiocarcinoma, Metastatic,|                                                                          |            |
           Liver                           |                                                                          |          1 |
 _____________________________________________________________________________________________________________________|            |
 NERVOUS SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 RESPIRATORY SYSTEM                        |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Larynx                                  | +  +  +  +  +  M  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
                                            __________________________________________________________________________|____________|
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Alveolar/Bronchiolar Adenoma         |    X  X                 X  X     X                                       |          9 |
      Alveolar/Bronchiolar Carcinoma       |                                  X                                   X   |          3 |
      Alveolar/Bronchiolar Carcinoma,      |                                                                          |            |
          Multiple                         |                                                                          |          1 |
      Hepatoblastoma, Metastatic, Liver    |                                                                          |          1 |
      Hepatocellular Carcinoma, Metastatic,|                                                                          |            |
           Liver                           |          X                                      X                 X      |          5 |
      Histiocytic Sarcoma                  |                               X                                          |          1 |
                                            __________________________________________________________________________|____________|
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Trachea                                 | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
 _____________________________________________________________________________________________________________________|            |
 SPECIAL SENSES SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Eye                                     |                                                                          |   1        |
                                            __________________________________________________________________________|____________|
   Harderian Gland                         |                   +                 +                       +            |   4        |
 __________________________________________________________________________________________________________________________________ 

                         * : 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: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 6| 6| 6| 5| 7| 7| 6| 4| 7| 7| 7| 7| 6| 7| 7| 7| 5| 5| 4| 7| 7| 5| 6| 7| 6|            |
                             DAY ON TEST   | 7| 4| 4| 5| 3| 3| 5| 8| 3| 3| 1| 3| 8| 3| 2| 3| 1| 3| 8| 3| 3| 7| 4| 3| 1|            |
                                           | 6| 0| 9| 5| 3| 4| 2| 2| 4| 3| 1| 4| 6| 4| 5| 3| 6| 3| 6| 3| 4| 9| 3| 4| 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      |
   B6C3F1 MICE 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|            |
 __________________________________________________________________________________________________________________________________ 
 SPECIAL SENSES SYSTEM - cont              |                                                                          |            |
                                           |                                                                          |            |
      Adenoma                              |                   X                 X                       X            |          4 |
 _____________________________________________________________________________________________________________________|            |
 URINARY SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Kidney                                  | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Urinary Bladder                         | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  A  +  +  +  A  +  +|  46        |
 __________________________________________________________________________________________________________________________________ 
 SYSTEMIC LESIONS                          |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Multiple Organs                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Histiocytic Sarcoma                  |                               X                                          |          1 |
      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  37                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 5| 7| 7| 7| 6| 7| 7| 7| 6| 6| 7| 7| 4| 7| 7| 5| 7| 7| 6| 7| 7| 7| 7| 6| 5|             
                             DAY ON TEST   | 4| 3| 3| 3| 1| 3| 2| 3| 6| 1| 3| 3| 6| 3| 3| 8| 3| 3| 9| 3| 2| 3| 3| 8| 0|             
                                           | 1| 3| 3| 3| 1| 3| 0| 4| 6| 7| 3| 4| 0| 4| 3| 3| 4| 4| 0| 4| 6| 4| 3| 7| 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|             
   B6C3F1 MICE 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                               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Gallbladder                             | +  +  +  +  +  +  M  +  M  M  +  +  +  +  +  M  +  +  +  +  +  M  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Colon                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Cecum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Duodenum               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Polyp Adenomatous                    |                                                                          |             
                                            __________________________________________________________________________|             
   Intestine Small, Jejunum                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Carcinoma                            |                                                                          |             
                                            __________________________________________________________________________|             
   Intestine Small, Ileum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hemangiosarcoma                      |                                                                      X   |             
      Hepatocellular Carcinoma             | X  X        X  X     X  X  X  X  X  X  X  X  X  X     X     X           X|             
      Hepatocellular Carcinoma, Multiple   |       X                                                                  |             
      Hepatocellular Adenoma               |          X     X  X        X     X     X           X                     |             
      Hepatocellular Adenoma, Multiple     |    X                    X                                X     X         |             
      Lymphoma Malignant                   |                                                             X            |             
                                            __________________________________________________________________________|             
   Mesentery                               |                                              +                       +   |             
      Hemangiosarcoma                      |                                                                      X   |             
                                            __________________________________________________________________________|             
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Squamous Cell Carcinoma              |                                                                          |             
                                            __________________________________________________________________________|             
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Serosa, Hepatocellular Carcinoma,    |                                                                          |             
           Metastatic, Liver               |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 CARDIOVASCULAR SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hemangiosarcoma                      |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM                          |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Adenoma                              |                                                    X                     |             
                                            __________________________________________________________________________|             
   Parathyroid Gland                       | M  +  +  +  M  +  +  +  M  +  +  +  +  +  +  M  M  +  +  +  +  +  M  +  +|             
                                            __________________________________________________________________________|             
   Pituitary Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 GENERAL BODY SYSTEM                       |                                                                          |             
                                           |                                                                          |             
    None                                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 GENITAL SYSTEM                            |                                                                          |             
                                           |                                                                          |             
 _____________________________________________________________________________________________________________________|             

                                                             Page  38                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 5| 7| 7| 7| 6| 7| 7| 7| 6| 6| 7| 7| 4| 7| 7| 5| 7| 7| 6| 7| 7| 7| 7| 6| 5|             
                             DAY ON TEST   | 4| 3| 3| 3| 1| 3| 2| 3| 6| 1| 3| 3| 6| 3| 3| 8| 3| 3| 9| 3| 2| 3| 3| 8| 0|             
                                           | 1| 3| 3| 3| 1| 3| 0| 4| 6| 7| 3| 4| 0| 4| 3| 3| 4| 4| 0| 4| 6| 4| 3| 7| 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|             
   B6C3F1 MICE 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|             
 _____________________________________________________________________________________________________________________|             
 GENITAL SYSTEM - cont                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Epididymis                              | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Preputial Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Prostate                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Seminal Vesicle                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Testes                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Interstitial Cell, Adenoma           |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hemangiosarcoma                      |                                                                      X   |             
      Lymphoma Malignant                   |                                                             X            |             
                                            __________________________________________________________________________|             
   Lymph Node                              |                            +                                             |             
                                            __________________________________________________________________________|             
   Lymph Node, Bronchial                   | +  M  M  M  +  M  +  M  +  +  M  +  M  M  +  +  M  M  M  +  +  M  +  +  M|             
      Lymphoma Malignant                   |                                                             X            |             
                                            __________________________________________________________________________|             
   Lymph Node, Mandibular                  | M  +  +  M  +  M  +  M  +  M  +  M  M  M  M  M  M  +  M  +  M  M  M  M  M|             
                                            __________________________________________________________________________|             
   Lymph Node, Mesenteric                  | +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hemangiosarcoma                      |                                                                          |             
      Lymphoma Malignant                   |                                                             X            |             
                                            __________________________________________________________________________|             
   Lymph Node, Mediastinal                 | +  +  +  M  M  +  M  +  +  +  +  +  M  +  +  +  M  M  +  M  M  +  M  M  +|             
                                            __________________________________________________________________________|             
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hemangiosarcoma                      |                                                                      X   |             
      Lymphoma Malignant                   |                                                             X            |             
                                            __________________________________________________________________________|             
   Thymus                                  | I  +  +  +  M  +  +  M  +  +  +  +  M  M  +  +  +  +  M  +  M  M  M  M  M|             
 _____________________________________________________________________________________________________________________|             
 INTEGUMENTARY SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Mammary Gland                           | M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M|             
                                            __________________________________________________________________________|             
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hemangiosarcoma                      |                                  X                                       |             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM                    |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 NERVOUS SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 RESPIRATORY SYSTEM                        |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Alveolar/Bronchiolar Adenoma         |             X                       X  X                    X            |             
      Alveolar/Bronchiolar Adenoma,        |                                                                          |             
          Multiple                         |                   X                                X                     |             
      Alveolar/Bronchiolar Carcinoma       |       X                                X                                 |             
      Hepatocellular Carcinoma, Metastatic,|                                                                          |             
           Liver                           |                X                                                         |             
 _____________________________________________________________________________________________________________________|             

                                                             Page  39                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 5| 7| 7| 7| 6| 7| 7| 7| 6| 6| 7| 7| 4| 7| 7| 5| 7| 7| 6| 7| 7| 7| 7| 6| 5|             
                             DAY ON TEST   | 4| 3| 3| 3| 1| 3| 2| 3| 6| 1| 3| 3| 6| 3| 3| 8| 3| 3| 9| 3| 2| 3| 3| 8| 0|             
                                           | 1| 3| 3| 3| 1| 3| 0| 4| 6| 7| 3| 4| 0| 4| 3| 3| 4| 4| 0| 4| 6| 4| 3| 7| 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|             
   B6C3F1 MICE 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|             
 _____________________________________________________________________________________________________________________|             
 RESPIRATORY SYSTEM - cont                 |                                                                          |             
                                           |                                                                          |             
      Lymphoma Malignant                   |                                                             X            |             
                                            __________________________________________________________________________|             
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 SPECIAL SENSES SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Ear                                     |                                                                      +   |             
                                            __________________________________________________________________________|             
   Harderian Gland                         |       +                                                                 +|             
      Adenoma                              |       X                                                                  |             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Lymphoma Malignant                   |                                                             X            |             
      Renal Tubule, Adenoma                |                                                                          |             
                                            __________________________________________________________________________|             
   Urinary Bladder                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 SYSTEMIC LESIONS                          |                                                                          |             
                                            __________________________________________________________________________|             
   Multiple Organs                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Lymphoma Malignant                   |                                                             X            |             
 _____________________________________________________________________________________________________________________|             

                                                             Page  40                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 7| 7| 7| 6| 7| 6| 7| 7| 7| 7| 6| 7| 7| 7| 6| 5| 7| 7| 7| 7| 6| 6| 7| 7|            |
                             DAY ON TEST   | 0| 3| 3| 3| 4| 3| 8| 3| 3| 3| 3| 6| 3| 3| 3| 1| 9| 3| 3| 3| 3| 5| 5| 3| 3|            |
                                           | 9| 4| 3| 3| 9| 3| 5| 3| 3| 3| 4| 6| 3| 4| 3| 4| 9| 4| 4| 3| 4| 3| 2| 3| 3|            |
 _____________________________________________________________________________________________________________________|     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      |
   B6C3F1 MICE 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        |
                                            __________________________________________________________________________|____________|
   Gallbladder                             | +  +  +  +  M  +  +  M  +  +  +  +  +  +  +  +  A  +  M  +  +  +  +  +  +|  41        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Colon                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Cecum                  | +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Duodenum               | +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Polyp Adenomatous                    |                                                                      X   |          1 |
                                            __________________________________________________________________________|____________|
   Intestine Small, Jejunum                | +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +|  48        |
      Carcinoma                            |                X                                                         |          1 |
                                            __________________________________________________________________________|____________|
   Intestine Small, Ileum                  | +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hemangiosarcoma                      |    X              X        X                                             |          4 |
      Hepatocellular Carcinoma             | X  X     X  X     X  X              X        X  X     X     X  X  X  X  X|         32 |
      Hepatocellular Carcinoma, Multiple   |                                                                          |          1 |
      Hepatocellular Adenoma               |          X                    X                             X  X        X|         12 |
      Hepatocellular Adenoma, Multiple     |       X              X                       X           X           X   |          9 |
      Lymphoma Malignant                   |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Mesentery                               |                               +  +                                       |   4        |
      Hemangiosarcoma                      |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Squamous Cell Carcinoma              |                      X           X                                       |          2 |
                                            __________________________________________________________________________|____________|
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Serosa, Hepatocellular Carcinoma,    |                                                                          |            |
           Metastatic, Liver               |                   X                                                      |          1 |
 _____________________________________________________________________________________________________________________|            |
 CARDIOVASCULAR SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hemangiosarcoma                      |                            X                                             |          1 |
 _____________________________________________________________________________________________________________________|            |
 ENDOCRINE SYSTEM                          |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Adenoma                              |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Parathyroid Gland                       | +  +  M  +  +  M  +  M  +  +  +  +  M  M  +  M  +  +  +  +  +  M  I  +  +|  36        |
                                            __________________________________________________________________________|____________|
   Pituitary Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Thyroid 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  41                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 7| 7| 7| 6| 7| 6| 7| 7| 7| 7| 6| 7| 7| 7| 6| 5| 7| 7| 7| 7| 6| 6| 7| 7|            |
                             DAY ON TEST   | 0| 3| 3| 3| 4| 3| 8| 3| 3| 3| 3| 6| 3| 3| 3| 1| 9| 3| 3| 3| 3| 5| 5| 3| 3|            |
                                           | 9| 4| 3| 3| 9| 3| 5| 3| 3| 3| 4| 6| 3| 4| 3| 4| 9| 4| 4| 3| 4| 3| 2| 3| 3|            |
 _____________________________________________________________________________________________________________________|     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      |
   B6C3F1 MICE 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|            |
 __________________________________________________________________________________________________________________________________ 
 GENERAL BODY SYSTEM                       |                                                                          |            |
                                           |                                                                          |            |
    None                                   |                                                                          |            |
 _____________________________________________________________________________________________________________________|            |
 GENITAL SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Epididymis                              | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Preputial Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Prostate                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Seminal Vesicle                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Testes                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Interstitial Cell, Adenoma           |                                                          X               |          1 |
 _____________________________________________________________________________________________________________________|            |
 HEMATOPOIETIC SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hemangiosarcoma                      |                            X                                             |          2 |
      Lymphoma Malignant                   |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Lymph Node                              |                                                                          |   1        |
                                            __________________________________________________________________________|____________|
   Lymph Node, Bronchial                   | M  M  M  +  +  M  M  M  M  +  +  +  +  M  M  +  +  +  I  +  M  +  M  M  +|  24        |
      Lymphoma Malignant                   |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mandibular                  | +  M  M  +  M  +  M  +  +  +  +  M  +  +  +  M  M  +  M  M  M  M  +  M  +|  21        |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
      Hemangiosarcoma                      |                      X                                                   |          1 |
      Lymphoma Malignant                   |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mediastinal                 | M  +  M  +  M  M  M  M  +  M  +  +  M  +  +  +  +  +  +  M  +  M  +  M  M|  28        |
                                            __________________________________________________________________________|____________|
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hemangiosarcoma                      |                   X        X                                             |          3 |
      Lymphoma Malignant                   |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Thymus                                  | M  +  +  +  M  +  M  +  M  M  +  +  +  I  +  +  +  +  M  +  +  +  +  +  M|  31        |
 _____________________________________________________________________________________________________________________|            |
 INTEGUMENTARY SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Mammary Gland                           | M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M|            |
                                            __________________________________________________________________________|____________|
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hemangiosarcoma                      |                                                                          |          1 |
 _____________________________________________________________________________________________________________________|            |
 MUSCULOSKELETAL SYSTEM                    |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 NERVOUS SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 RESPIRATORY 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  42                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 7| 7| 7| 6| 7| 6| 7| 7| 7| 7| 6| 7| 7| 7| 6| 5| 7| 7| 7| 7| 6| 6| 7| 7|            |
                             DAY ON TEST   | 0| 3| 3| 3| 4| 3| 8| 3| 3| 3| 3| 6| 3| 3| 3| 1| 9| 3| 3| 3| 3| 5| 5| 3| 3|            |
                                           | 9| 4| 3| 3| 9| 3| 5| 3| 3| 3| 4| 6| 3| 4| 3| 4| 9| 4| 4| 3| 4| 3| 2| 3| 3|            |
 _____________________________________________________________________________________________________________________|     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      |
   B6C3F1 MICE 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|            |
 __________________________________________________________________________________________________________________________________ 
 RESPIRATORY SYSTEM - cont                 |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Larynx                                  | +  +  +  +  +  +  +  I  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Alveolar/Bronchiolar Adenoma         |                         X  X                       X           X  X      |          9 |
      Alveolar/Bronchiolar Adenoma,        |                                                                          |            |
          Multiple                         |                                        X                                 |          3 |
      Alveolar/Bronchiolar Carcinoma       |                                        X           X                 X   |          5 |
      Hepatocellular Carcinoma, Metastatic,|                                                                          |            |
           Liver                           |    X                                                  X     X  X         |          5 |
      Lymphoma Malignant                   |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 SPECIAL SENSES SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Ear                                     |                                                                          |   1        |
                                            __________________________________________________________________________|____________|
   Harderian Gland                         |             +                                               +            |   4        |
      Adenoma                              |                                                             X            |          2 |
 _____________________________________________________________________________________________________________________|            |
 URINARY SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Lymphoma Malignant                   |                                                                          |          1 |
      Renal Tubule, Adenoma                |                                                    X                     |          1 |
                                            __________________________________________________________________________|____________|
   Urinary Bladder                         | +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
 __________________________________________________________________________________________________________________________________ 
 SYSTEMIC LESIONS                          |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Multiple Organs                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Lymphoma 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  43                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 7| 7| 5| 7| 6| 7| 5| 5| 7| 7| 7| 6| 7| 7| 5| 7| 7| 7| 7| 7| 7| 7| 5| 7|             
                             DAY ON TEST   | 3| 3| 3| 1| 3| 7| 3| 0| 3| 3| 0| 3| 8| 3| 3| 4| 3| 3| 0| 3| 3| 3| 0| 5| 3|             
                                           | 3| 3| 4| 0| 3| 0| 4| 5| 4| 3| 9| 3| 1| 3| 4| 8| 3| 4| 8| 3| 3| 3| 5| 5| 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|             
   B6C3F1 MICE 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                               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Gallbladder                             | +  M  +  +  M  A  +  +  M  +  +  +  A  +  +  A  +  +  +  +  +  +  M  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Colon                  | +  +  +  +  +  A  +  +  +  +  +  +  A  +  +  A  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Rectum                 | +  +  +  +  +  A  +  +  +  +  +  +  A  +  +  A  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Cecum                  | +  +  +  +  +  A  +  +  +  +  +  +  A  +  +  A  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Duodenum               | +  +  +  +  +  A  +  +  +  +  +  +  A  +  +  A  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Jejunum                | +  +  +  +  +  A  +  +  +  +  +  +  A  +  +  A  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Ileum                  | +  +  +  +  +  A  +  +  +  +  +  +  A  +  +  A  +  +  +  +  +  +  +  +  +|             
      Lymphoma Malignant                   |                                                                          |             
                                            __________________________________________________________________________|             
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hemangiosarcoma                      |                               X     X           X  X                     |             
      Hepatoblastoma                       |    X                                                              X      |             
      Hepatocellular Carcinoma             |    X        X  X  X  X  X     X        X     X        X  X  X        X   |             
      Hepatocellular Carcinoma, Multiple   |                                                                          |             
      Hepatocellular Adenoma               | X              X     X     X           X  X        X           X        X|             
      Hepatocellular Adenoma, Multiple     |             X     X           X                 X                        |             
                                            __________________________________________________________________________|             
   Mesentery                               | +        +                                                               |             
      Hepatocellular Carcinoma, Metastatic,|                                                                          |             
           Liver                           |                                                                          |             
                                            __________________________________________________________________________|             
   Pancreas                                | +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Squamous Cell Papilloma              |                                                                X         |             
                                            __________________________________________________________________________|             
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 CARDIOVASCULAR SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Blood Vessel                            |                            +                                             |             
                                            __________________________________________________________________________|             
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM                          |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Islets, Pancreatic                      | +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Parathyroid Gland                       | M  +  M  +  +  +  M  M  M  M  +  +  +  +  +  M  +  +  M  +  M  M  +  M  +|             
                                            __________________________________________________________________________|             
   Pituitary Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Follicular Cell, Carcinoma           |                                                                X         |             
 _____________________________________________________________________________________________________________________|             
 GENERAL BODY SYSTEM                       |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Tissue NOS                              |                                              +                           |             
 _____________________________________________________________________________________________________________________|             
 GENITAL SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Epididymis                              | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leiomyoma                            |                      X                                                   |             
 _____________________________________________________________________________________________________________________|             

                                                             Page  44                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 7| 7| 5| 7| 6| 7| 5| 5| 7| 7| 7| 6| 7| 7| 5| 7| 7| 7| 7| 7| 7| 7| 5| 7|             
                             DAY ON TEST   | 3| 3| 3| 1| 3| 7| 3| 0| 3| 3| 0| 3| 8| 3| 3| 4| 3| 3| 0| 3| 3| 3| 0| 5| 3|             
                                           | 3| 3| 4| 0| 3| 0| 4| 5| 4| 3| 9| 3| 1| 3| 4| 8| 3| 4| 8| 3| 3| 3| 5| 5| 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|             
   B6C3F1 MICE 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|             
 _____________________________________________________________________________________________________________________|             
 GENITAL SYSTEM - cont                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Preputial Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Prostate                                | +  +  +  +  M  +  +  +  +  +  +  +  A  +  +  +  M  +  +  +  +  +  +  M  +|             
                                            __________________________________________________________________________|             
   Seminal Vesicle                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Testes                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Lymph Node                              |                                                                          |             
      Renal, Lymphoma Malignant            |                                                                          |             
                                            __________________________________________________________________________|             
   Lymph Node, Bronchial                   | M  +  M  M  +  A  +  M  +  M  M  M  +  +  +  M  +  +  M  +  +  +  +  M  M|             
      Lymphoma Malignant                   |                                                                          |             
                                            __________________________________________________________________________|             
   Lymph Node, Mandibular                  | M  M  M  M  +  +  M  M  M  +  +  +  M  +  +  M  +  M  +  +  +  +  M  +  +|             
                                            __________________________________________________________________________|             
   Lymph Node, Mesenteric                  | M  +  +  M  +  A  +  +  M  +  +  +  A  +  +  A  +  +  +  +  +  +  +  +  +|             
      Lymphoma Malignant                   |                                                                          |             
                                            __________________________________________________________________________|             
   Lymph Node, Mediastinal                 | +  +  I  +  +  +  M  +  +  +  +  M  +  +  +  +  +  +  M  M  +  M  M  M  M|             
      Lymphoma Malignant                   |                                                                          |             
                                            __________________________________________________________________________|             
   Spleen                                  | +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hemangiosarcoma                      |                                     X                                    |             
      Lymphoma Malignant                   |                                                                          |             
                                            __________________________________________________________________________|             
   Thymus                                  | M  +  +  M  +  +  +  M  M  +  +  +  M  +  +  M  M  M  M  +  +  +  +  +  +|             
      Lymphoma Malignant                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 INTEGUMENTARY SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Mammary Gland                           | M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M|             
                                            __________________________________________________________________________|             
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM                    |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 NERVOUS SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 RESPIRATORY SYSTEM                        |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Larynx                                  | +  +  +  +  +  A  +  +  +  +  +  I  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Alveolar/Bronchiolar Adenoma         |                X                    X     X  X        X           X  X  X|             
      Alveolar/Bronchiolar Adenoma,        |                                                                          |             
          Multiple                         |                                                                X         |             
      Alveolar/Bronchiolar Carcinoma       |       X                    X              X                              |             
      Alveolar/Bronchiolar Carcinoma,      |                                                                          |             
          Multiple                         |                               X                                          |             
      Hepatocellular Carcinoma, Metastatic,|                                                                          |             
           Liver                           |                                              X        X                  |             
      Lymphoma Malignant                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             

                                                             Page  45                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 7| 7| 5| 7| 6| 7| 5| 5| 7| 7| 7| 6| 7| 7| 5| 7| 7| 7| 7| 7| 7| 7| 5| 7|             
                             DAY ON TEST   | 3| 3| 3| 1| 3| 7| 3| 0| 3| 3| 0| 3| 8| 3| 3| 4| 3| 3| 0| 3| 3| 3| 0| 5| 3|             
                                           | 3| 3| 4| 0| 3| 0| 4| 5| 4| 3| 9| 3| 1| 3| 4| 8| 3| 4| 8| 3| 3| 3| 5| 5| 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|             
   B6C3F1 MICE 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                 |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Nose                                    | +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 SPECIAL SENSES SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Eye                                     | +                                                                        |             
                                            __________________________________________________________________________|             
   Harderian Gland                         | +                             +                 +  +                     |             
      Adenoma                              | X                                               X                        |             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Ureter                                  |    +                                                                     |             
                                            __________________________________________________________________________|             
   Urinary Bladder                         | +  +  +  +  +  A  +  +  +  +  +  +  A  +  +  A  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 SYSTEMIC LESIONS                          |                                                                          |             
                                            __________________________________________________________________________|             
   Multiple Organs                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Lymphoma Malignant                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             

                                                             Page  46                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 7| 6| 7| 6| 7| 6| 7| 6| 6| 6| 4| 6| 7| 6| 5| 4| 7| 7| 5| 5| 5| 6| 7| 7|            |
                             DAY ON TEST   | 3| 3| 1| 3| 8| 0| 4| 3| 4| 5| 8| 4| 3| 3| 5| 6| 8| 3| 3| 2| 6| 9| 9| 3| 3|            |
                                           | 3| 3| 0| 4| 1| 6| 5| 3| 5| 2| 7| 0| 9| 4| 3| 0| 3| 3| 4| 3| 1| 7| 9| 4| 3|            |
 _____________________________________________________________________________________________________________________|     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      |
   B6C3F1 MICE 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        |
                                            __________________________________________________________________________|____________|
   Gallbladder                             | +  +  +  +  +  +  +  +  +  +  +  A  +  +  A  +  A  +  +  A  +  +  +  M  +|  38        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Colon                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +|  46        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  I  +  +  +  +  +  M  +  +  +  +  +  +  +  +|  45        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Cecum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  A  +  +  +  +  +  +  +  +|  45        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Duodenum               | +  +  +  +  A  +  +  +  +  +  +  A  +  +  A  +  A  +  +  M  +  +  +  +  +|  42        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Jejunum                | +  +  +  +  A  +  +  +  +  +  +  A  +  +  A  +  A  +  +  A  +  +  +  +  +|  42        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Ileum                  | +  +  +  +  A  +  +  +  +  +  +  +  +  +  A  +  A  +  +  A  +  +  +  +  +|  43        |
      Lymphoma Malignant                   |                            X                                             |          1 |
                                            __________________________________________________________________________|____________|
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hemangiosarcoma                      |       X                       X     X                    X               |          8 |
      Hepatoblastoma                       |                                                                          |          2 |
      Hepatocellular Carcinoma             |    X  X  X  X     X     X     X  X  X     X  X  X           X  X  X  X   |         29 |
      Hepatocellular Carcinoma, Multiple   |                                                    X                     |          1 |
      Hepatocellular Adenoma               |                X                 X     X     X        X        X     X   |         16 |
      Hepatocellular Adenoma, Multiple     |          X           X              X                    X              X|          9 |
                                            __________________________________________________________________________|____________|
   Mesentery                               |                +                                   +                 +   |   5        |
      Hepatocellular Carcinoma, Metastatic,|                                                                          |            |
           Liver                           |                                                    X                     |          1 |
                                            __________________________________________________________________________|____________|
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Squamous Cell Papilloma              |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 CARDIOVASCULAR SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Blood Vessel                            | +                                                        +               |   3        |
                                            __________________________________________________________________________|____________|
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 ENDOCRINE SYSTEM                          |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Parathyroid Gland                       | M  M  +  +  M  M  M  M  +  M  +  M  M  +  M  +  M  M  +  +  M  M  +  +  M|  24        |
                                            __________________________________________________________________________|____________|
   Pituitary Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +|  48        |
                                            __________________________________________________________________________|____________|
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Follicular Cell, Carcinoma           |                                                                          |          1 |
 _____________________________________________________________________________________________________________________|            |
 GENERAL BODY 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  47                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 7| 6| 7| 6| 7| 6| 7| 6| 6| 6| 4| 6| 7| 6| 5| 4| 7| 7| 5| 5| 5| 6| 7| 7|            |
                             DAY ON TEST   | 3| 3| 1| 3| 8| 0| 4| 3| 4| 5| 8| 4| 3| 3| 5| 6| 8| 3| 3| 2| 6| 9| 9| 3| 3|            |
                                           | 3| 3| 0| 4| 1| 6| 5| 3| 5| 2| 7| 0| 9| 4| 3| 0| 3| 3| 4| 3| 1| 7| 9| 4| 3|            |
 _____________________________________________________________________________________________________________________|     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      |
   B6C3F1 MICE 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|            |
 __________________________________________________________________________________________________________________________________ 
 GENERAL BODY SYSTEM - cont                |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Tissue NOS                              |                                                                          |   1        |
 _____________________________________________________________________________________________________________________|            |
 GENITAL SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Epididymis                              | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Leiomyoma                            |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Preputial Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Prostate                                | +  +  I  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  44        |
                                            __________________________________________________________________________|____________|
   Seminal Vesicle                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Testes                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 HEMATOPOIETIC SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Lymph Node                              |                            +        +                                    |   2        |
      Renal, Lymphoma Malignant            |                            X                                             |          1 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Bronchial                   | +  +  +  +  +  +  +  M  +  +  +  M  +  +  +  M  M  M  M  M  +  +  M  M  M|  28        |
      Lymphoma Malignant                   |                            X                                             |          1 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mandibular                  | M  M  M  +  +  +  M  +  +  M  M  +  M  +  +  +  M  +  +  M  +  +  M  +  +|  29        |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +|  43        |
      Lymphoma Malignant                   |                            X                                             |          1 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mediastinal                 | +  M  +  M  M  M  +  M  M  +  +  +  +  +  +  M  +  +  +  M  M  +  +  +  M|  31        |
      Lymphoma Malignant                   |                            X                                             |          1 |
                                            __________________________________________________________________________|____________|
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Hemangiosarcoma                      |                                                                          |          1 |
      Lymphoma Malignant                   |                            X                                             |          1 |
                                            __________________________________________________________________________|____________|
   Thymus                                  | +  +  M  +  +  M  +  +  +  +  +  M  +  +  M  M  M  +  +  +  M  +  I  +  +|  33        |
      Lymphoma Malignant                   |                            X                                             |          1 |
 _____________________________________________________________________________________________________________________|            |
 INTEGUMENTARY SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Mammary Gland                           | M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M|            |
                                            __________________________________________________________________________|____________|
   Skin                                    | +  +  +  +  +  +  +  +  +  I  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
 _____________________________________________________________________________________________________________________|            |
 MUSCULOSKELETAL SYSTEM                    |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 NERVOUS SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 RESPIRATORY SYSTEM                        |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
 __________________________________________________________________________________________________________________________________ 

                         * : 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  48                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 7| 6| 7| 6| 7| 6| 7| 6| 6| 6| 4| 6| 7| 6| 5| 4| 7| 7| 5| 5| 5| 6| 7| 7|            |
                             DAY ON TEST   | 3| 3| 1| 3| 8| 0| 4| 3| 4| 5| 8| 4| 3| 3| 5| 6| 8| 3| 3| 2| 6| 9| 9| 3| 3|            |
                                           | 3| 3| 0| 4| 1| 6| 5| 3| 5| 2| 7| 0| 9| 4| 3| 0| 3| 3| 4| 3| 1| 7| 9| 4| 3|            |
 _____________________________________________________________________________________________________________________|     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      |
   B6C3F1 MICE 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|            |
 __________________________________________________________________________________________________________________________________ 
 RESPIRATORY SYSTEM - cont                 |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Alveolar/Bronchiolar Adenoma         |          X                             X              X                  |         11 |
      Alveolar/Bronchiolar Adenoma,        |                                                                          |            |
          Multiple                         |                                                                      X   |          2 |
      Alveolar/Bronchiolar Carcinoma       |                               X                                         X|          5 |
      Alveolar/Bronchiolar Carcinoma,      |                                                                          |            |
          Multiple                         |                                                                   X      |          2 |
      Hepatocellular Carcinoma, Metastatic,|                                                                          |            |
           Liver                           |       X     X                                   X                 X      |          6 |
      Lymphoma Malignant                   |                            X                                             |          1 |
                                            __________________________________________________________________________|____________|
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +|  48        |
                                            __________________________________________________________________________|____________|
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 SPECIAL SENSES SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Eye                                     |                                                                          |   1        |
                                            __________________________________________________________________________|____________|
   Harderian Gland                         |                                                                          |   4        |
      Adenoma                              |                                                                          |          2 |
 _____________________________________________________________________________________________________________________|            |
 URINARY SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Ureter                                  |                                                                          |   1        |
                                            __________________________________________________________________________|____________|
   Urinary Bladder                         | +  +  I  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +|  45        |
 __________________________________________________________________________________________________________________________________ 
 SYSTEMIC LESIONS                          |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Multiple Organs                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      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  49                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 5| 7| 6| 6| 4| 7| 7| 7| 7| 7| 5| 5| 5| 7| 5| 7| 5| 7| 7| 5| 5| 7| 6| 7|             
                             DAY ON TEST   | 3| 3| 3| 1| 1| 1| 3| 3| 3| 3| 3| 4| 6| 2| 3| 2| 3| 5| 3| 3| 5| 3| 1| 5| 3|             
                                           | 3| 3| 3| 1| 3| 4| 3| 4| 3| 3| 4| 1| 0| 7| 4| 4| 4| 5| 4| 3| 2| 6| 3| 3| 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|             
   B6C3F1 MICE 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                               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Gallbladder                             | M  +  +  A  +  +  M  +  +  +  +  +  A  +  +  M  +  M  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Colon                  | +  +  +  A  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Rectum                 | +  +  +  A  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Cecum                  | +  +  +  A  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Duodenum               | +  +  +  A  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Jejunum                | +  +  +  A  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Ileum                  | +  +  +  A  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hemangiosarcoma                      |                      X                                               X   |             
      Hepatoblastoma                       |                            X                             X               |             
      Hepatocellular Carcinoma             | X                 X     X           X  X     X  X           X  X  X  X   |             
      Hepatocellular Carcinoma, Multiple   |                            X  X  X                 X                     |             
      Hepatocellular Adenoma               |    X  X  X           X                                                   |             
      Hepatocellular Adenoma, Multiple     |                                                 X     X     X        X   |             
      Histiocytic Sarcoma                  |                                                                          |             
      Sarcoma                              |                                              X                           |             
                                            __________________________________________________________________________|             
   Mesentery                               |       +              +              +        +                           |             
      Hemangiosarcoma                      |                      X                                                   |             
      Sarcoma, Metastatic, Liver           |                                              X                           |             
                                            __________________________________________________________________________|             
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Sarcoma, Metastatic, Liver           |                                              X                           |             
                                            __________________________________________________________________________|             
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Sarcoma, Metastatic, Liver           |                                              X                           |             
                                            __________________________________________________________________________|             
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Tooth                                   |                                           +                              |             
 _____________________________________________________________________________________________________________________|             
 CARDIOVASCULAR SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Alveolar/Bronchiolar Carcinoma,      |                                                                          |             
          Metastatic, Lung                 |                                                             X            |             
      Sarcoma, Metastatic, Liver           |                                              X                           |             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM                          |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Pheochromocytoma Benign              |                                                                          |             
                                            __________________________________________________________________________|             
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Parathyroid Gland                       | +  +  +  +  M  M  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  M  M  +|             
                                            __________________________________________________________________________|             
   Pituitary Gland                         | +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Follicular Cell, Adenoma             |                      X                                                   |             
 _____________________________________________________________________________________________________________________|             
 GENERAL BODY SYSTEM                       |                                                                          |             
                                           |                                                                          |             
    None                                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             

                                                             Page  50                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 5| 7| 6| 6| 4| 7| 7| 7| 7| 7| 5| 5| 5| 7| 5| 7| 5| 7| 7| 5| 5| 7| 6| 7|             
                             DAY ON TEST   | 3| 3| 3| 1| 1| 1| 3| 3| 3| 3| 3| 4| 6| 2| 3| 2| 3| 5| 3| 3| 5| 3| 1| 5| 3|             
                                           | 3| 3| 3| 1| 3| 4| 3| 4| 3| 3| 4| 1| 0| 7| 4| 4| 4| 5| 4| 3| 2| 6| 3| 3| 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|             
   B6C3F1 MICE 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|             
 _____________________________________________________________________________________________________________________|             
 GENITAL SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Epididymis                              | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Preputial Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Prostate                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Seminal Vesicle                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Testes                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hemangiosarcoma                      | X                                                                        |             
                                            __________________________________________________________________________|             
   Lymph Node                              |                                        +     +                           |             
      Iliac, Sarcoma, Metastatic, Liver    |                                              X                           |             
                                            __________________________________________________________________________|             
   Lymph Node, Bronchial                   | M  +  +  +  M  +  +  +  +  M  +  +  M  M  M  +  M  M  +  M  +  +  M  I  +|             
      Alveolar/Bronchiolar Carcinoma,      |                                                                          |             
          Metastatic, Lung                 |                                                             X            |             
      Sarcoma, Metastatic, Liver           |                                              X                           |             
                                            __________________________________________________________________________|             
   Lymph Node, Mandibular                  | +  +  +  +  +  M  M  +  M  M  +  M  M  A  +  +  +  +  M  +  M  +  M  +  +|             
                                            __________________________________________________________________________|             
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Sarcoma, Metastatic, Liver           |                                              X                           |             
                                            __________________________________________________________________________|             
   Lymph Node, Mediastinal                 | +  +  +  I  +  M  M  +  +  M  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +|             
      Alveolar/Bronchiolar Carcinoma,      |                                                                          |             
          Metastatic, Lung                 |                                                             X            |             
      Sarcoma, Metastatic, Liver           |                                              X                           |             
                                            __________________________________________________________________________|             
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hemangiosarcoma                      | X                                                                        |             
      Histiocytic Sarcoma                  |                                                                          |             
                                            __________________________________________________________________________|             
   Thymus                                  | M  +  +  +  M  M  +  +  +  +  +  +  A  M  M  M  +  +  M  M  M  M  +  M  +|             
 _____________________________________________________________________________________________________________________|             
 INTEGUMENTARY SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Mammary Gland                           | M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M|             
                                            __________________________________________________________________________|             
   Skin                                    | +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hemangiosarcoma                      | X                                                  X                     |             
      Subcutaneous Tissue, Carcinoma       |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM                    |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hemangiosarcoma                      | X                                                                        |             
                                            __________________________________________________________________________|             
   Skeletal Muscle                         |                                                             +            |             
      Alveolar/Bronchiolar Carcinoma,      |                                                                          |             
          Metastatic, Lung                 |                                                             X            |             
 _____________________________________________________________________________________________________________________|             
 NERVOUS SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Spinal Cord                             |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 RESPIRATORY SYSTEM                        |                                                                          |             
 _____________________________________________________________________________________________________________________|             

                                                             Page  51                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 5| 7| 6| 6| 4| 7| 7| 7| 7| 7| 5| 5| 5| 7| 5| 7| 5| 7| 7| 5| 5| 7| 6| 7|             
                             DAY ON TEST   | 3| 3| 3| 1| 1| 1| 3| 3| 3| 3| 3| 4| 6| 2| 3| 2| 3| 5| 3| 3| 5| 3| 1| 5| 3|             
                                           | 3| 3| 3| 1| 3| 4| 3| 4| 3| 3| 4| 1| 0| 7| 4| 4| 4| 5| 4| 3| 2| 6| 3| 3| 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|             
   B6C3F1 MICE 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                 |                                                                          |             
                                           |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  I  +  +|             
                                            __________________________________________________________________________|             
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Alveolar/Bronchiolar Adenoma         |          X        X                    X     X  X        X     X     X   |             
      Alveolar/Bronchiolar Adenoma,        |                                                                          |             
          Multiple                         |                      X  X                 X                              |             
      Alveolar/Bronchiolar Carcinoma       | X     X     X     X           X                             X            |             
      Alveolar/Bronchiolar Carcinoma,      |                                                                          |             
          Multiple                         |                                                       X                  |             
      Hemangiosarcoma, Metastatic, Liver   |                                                                          |             
      Hepatocellular Carcinoma, Metastatic,|                                                                          |             
           Liver                           |                               X     X        X                           |             
                                            __________________________________________________________________________|             
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 SPECIAL SENSES SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Eye                                     |                                                                          |             
                                            __________________________________________________________________________|             
   Harderian Gland                         |                                                                          |             
      Adenoma                              |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Alveolar/Bronchiolar Carcinoma,      |                                                                          |             
          Metastatic, Lung                 |                                                             X            |             
      Histiocytic Sarcoma                  |                                                                          |             
      Renal Tubule, Adenoma                |                         X                                                |             
                                            __________________________________________________________________________|             
   Ureter                                  |                               +                                          |             
                                            __________________________________________________________________________|             
   Urinary Bladder                         | +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 SYSTEMIC LESIONS                          |                                                                          |             
                                            __________________________________________________________________________|             
   Multiple Organs                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Histiocytic Sarcoma                  |                                                                          |             
 _____________________________________________________________________________________________________________________|             

                                                             Page  52                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 5| 7| 7| 7| 6| 6| 6| 6| 6| 7| 6| 7| 6| 5| 6| 5| 7| 6| 5| 5| 6| 3| 5| 7| 7|            |
                             DAY ON TEST   | 0| 3| 3| 3| 5| 4| 1| 7| 8| 3| 1| 3| 7| 5| 2| 5| 3| 0| 6| 6| 3| 9| 6| 3| 3|            |
                                           | 2| 4| 3| 4| 2| 9| 8| 3| 6| 3| 8| 3| 8| 5| 2| 5| 3| 8| 6| 1| 9| 9| 1| 3| 4|            |
 _____________________________________________________________________________________________________________________|     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      |
   B6C3F1 MICE 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        |
                                            __________________________________________________________________________|____________|
   Gallbladder                             | +  +  +  +  +  A  +  +  +  +  A  +  +  +  +  M  +  M  +  +  M  +  M  +  +|  38        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Colon                  | +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  47        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  47        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Cecum                  | +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  A  +  +  +  +  +  +  +  +  +|  46        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Duodenum               | +  +  +  +  +  A  +  +  +  +  A  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  45        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Jejunum                | +  +  +  +  +  A  +  +  +  +  A  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  45        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Ileum                  | +  +  +  +  +  A  +  +  +  +  A  +  +  +  +  A  +  A  +  +  +  +  +  +  +|  44        |
                                            __________________________________________________________________________|____________|
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hemangiosarcoma                      | X        X        X        X                       X                     |          7 |
      Hepatoblastoma                       |                                                                          |          2 |
      Hepatocellular Carcinoma             | X  X           X  X     X  X  X     X  X     X  X  X  X     X     X      |         26 |
      Hepatocellular Carcinoma, Multiple   |                                                                          |          4 |
      Hepatocellular Adenoma               |                X                                      X                  |          6 |
      Hepatocellular Adenoma, Multiple     |                      X                    X                          X   |          7 |
      Histiocytic Sarcoma                  |                         X                                                |          1 |
      Sarcoma                              |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Mesentery                               |                                                                          |   4        |
      Hemangiosarcoma                      |                                                                          |          1 |
      Sarcoma, Metastatic, Liver           |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Sarcoma, Metastatic, Liver           |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Sarcoma, Metastatic, Liver           |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Tooth                                   |                                                                          |   1        |
 _____________________________________________________________________________________________________________________|            |
 CARDIOVASCULAR SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Alveolar/Bronchiolar Carcinoma,      |                                                                          |            |
          Metastatic, Lung                 |                                                                          |          1 |
      Sarcoma, Metastatic, Liver           |                                                                          |          1 |
 _____________________________________________________________________________________________________________________|            |
 ENDOCRINE SYSTEM                          |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Pheochromocytoma Benign              |    X                                                                     |          1 |
                                            __________________________________________________________________________|____________|
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  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  53                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 5| 7| 7| 7| 6| 6| 6| 6| 6| 7| 6| 7| 6| 5| 6| 5| 7| 6| 5| 5| 6| 3| 5| 7| 7|            |
                             DAY ON TEST   | 0| 3| 3| 3| 5| 4| 1| 7| 8| 3| 1| 3| 7| 5| 2| 5| 3| 0| 6| 6| 3| 9| 6| 3| 3|            |
                                           | 2| 4| 3| 4| 2| 9| 8| 3| 6| 3| 8| 3| 8| 5| 2| 5| 3| 8| 6| 1| 9| 9| 1| 3| 4|            |
 _____________________________________________________________________________________________________________________|     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      |
   B6C3F1 MICE 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                   |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Parathyroid Gland                       | M  M  M  +  +  M  +  M  M  M  M  M  M  +  M  M  +  M  +  +  +  +  M  M  +|  30        |
                                            __________________________________________________________________________|____________|
   Pituitary Gland                         | +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  47        |
                                            __________________________________________________________________________|____________|
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Follicular Cell, Adenoma             |                                                                          |          1 |
 _____________________________________________________________________________________________________________________|            |
 GENERAL BODY SYSTEM                       |                                                                          |            |
                                           |                                                                          |            |
    None                                   |                                                                          |            |
 _____________________________________________________________________________________________________________________|            |
 GENITAL SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Epididymis                              | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Preputial Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Prostate                                | +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Seminal Vesicle                         | +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Testes                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 HEMATOPOIETIC SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hemangiosarcoma                      |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Lymph Node                              |                                                                          |   2        |
      Iliac, Sarcoma, Metastatic, Liver    |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Bronchial                   | M  M  +  +  M  M  M  M  M  +  +  +  +  M  M  M  +  M  M  +  +  M  M  +  +|  25        |
      Alveolar/Bronchiolar Carcinoma,      |                                                                          |            |
          Metastatic, Lung                 |                                                                          |          1 |
      Sarcoma, Metastatic, Liver           |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mandibular                  | +  M  +  +  M  +  +  M  +  M  +  I  +  +  +  M  M  +  +  +  M  +  M  +  +|  31        |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  M  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  47        |
      Sarcoma, Metastatic, Liver           |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mediastinal                 | +  +  +  +  M  +  +  +  I  M  +  +  M  +  M  M  M  +  M  +  +  +  +  M  M|  35        |
      Alveolar/Bronchiolar Carcinoma,      |                                                                          |            |
          Metastatic, Lung                 |                                                                          |          1 |
      Sarcoma, Metastatic, Liver           |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hemangiosarcoma                      |                            X                                             |          2 |
      Histiocytic Sarcoma                  |                         X                                                |          1 |
                                            __________________________________________________________________________|____________|
   Thymus                                  | M  M  M  M  M  +  +  M  +  +  +  +  +  +  M  +  +  M  +  +  M  +  +  M  +|  28        |
 _____________________________________________________________________________________________________________________|            |
 INTEGUMENTARY SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Mammary Gland                           | M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M|            |
                                            __________________________________________________________________________|____________|
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  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  54                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 5| 7| 7| 7| 6| 6| 6| 6| 6| 7| 6| 7| 6| 5| 6| 5| 7| 6| 5| 5| 6| 3| 5| 7| 7|            |
                             DAY ON TEST   | 0| 3| 3| 3| 5| 4| 1| 7| 8| 3| 1| 3| 7| 5| 2| 5| 3| 0| 6| 6| 3| 9| 6| 3| 3|            |
                                           | 2| 4| 3| 4| 2| 9| 8| 3| 6| 3| 8| 3| 8| 5| 2| 5| 3| 8| 6| 1| 9| 9| 1| 3| 4|            |
 _____________________________________________________________________________________________________________________|     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      |
   B6C3F1 MICE 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|            |
 __________________________________________________________________________________________________________________________________ 
 INTEGUMENTARY SYSTEM - cont               |                                                                          |            |
                                           |                                                                          |            |
      Hemangiosarcoma                      |                                                                          |          2 |
      Subcutaneous Tissue, Carcinoma       |                      X                                                   |          1 |
 _____________________________________________________________________________________________________________________|            |
 MUSCULOSKELETAL SYSTEM                    |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hemangiosarcoma                      |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Skeletal Muscle                         |                                                          +               |   2        |
      Alveolar/Bronchiolar Carcinoma,      |                                                                          |            |
          Metastatic, Lung                 |                                                                          |          1 |
 _____________________________________________________________________________________________________________________|            |
 NERVOUS SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Spinal Cord                             |                   +                                                      |   1        |
 _____________________________________________________________________________________________________________________|            |
 RESPIRATORY SYSTEM                        |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Alveolar/Bronchiolar Adenoma         |                X              X  X                       X  X            |         13 |
      Alveolar/Bronchiolar Adenoma,        |                                                                          |            |
          Multiple                         |             X           X                                                |          5 |
      Alveolar/Bronchiolar Carcinoma       |                      X     X        X                                    |          9 |
      Alveolar/Bronchiolar Carcinoma,      |                                                                          |            |
          Multiple                         |                                                                         X|          2 |
      Hemangiosarcoma, Metastatic, Liver   |          X                                                               |          1 |
      Hepatocellular Carcinoma, Metastatic,|                                                                          |            |
           Liver                           |                            X           X        X                 X      |          7 |
                                            __________________________________________________________________________|____________|
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 SPECIAL SENSES SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Eye                                     |                                                                +         |   1        |
                                            __________________________________________________________________________|____________|
   Harderian Gland                         |                      +  +                             +     +  +        +|   6        |
      Adenoma                              |                         X                                                |          1 |
 _____________________________________________________________________________________________________________________|            |
 URINARY SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Alveolar/Bronchiolar Carcinoma,      |                                                                          |            |
          Metastatic, Lung                 |                                                                          |          1 |
      Histiocytic Sarcoma                  |                         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  55                                                               
NTP Experiment-Test: 05156-06                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 03/19/97  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 17:33:53  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 5| 7| 7| 7| 6| 6| 6| 6| 6| 7| 6| 7| 6| 5| 6| 5| 7| 6| 5| 5| 6| 3| 5| 7| 7|            |
                             DAY ON TEST   | 0| 3| 3| 3| 5| 4| 1| 7| 8| 3| 1| 3| 7| 5| 2| 5| 3| 0| 6| 6| 3| 9| 6| 3| 3|            |
                                           | 2| 4| 3| 4| 2| 9| 8| 3| 6| 3| 8| 3| 8| 5| 2| 5| 3| 8| 6| 1| 9| 9| 1| 3| 4|            |
 _____________________________________________________________________________________________________________________|     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      |
   B6C3F1 MICE 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|            |
 __________________________________________________________________________________________________________________________________ 
 URINARY SYSTEM - cont                     |                                                                          |            |
                                           |                                                                          |            |
      Renal Tubule, Adenoma                |                                                                          |          1 |
                                            __________________________________________________________________________|____________|
   Ureter                                  |                                                                          |   1        |
                                            __________________________________________________________________________|____________|
   Urinary Bladder                         | +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
 __________________________________________________________________________________________________________________________________ 
 SYSTEMIC LESIONS                          |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Multiple Organs                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Histiocytic Sarcoma                  |                         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  56                                                               
                                  ------------------------------------------------------------                                      
                                  ----------              END OF REPORT             ----------                                      
                                  ------------------------------------------------------------                                      
NTP is located at the National Institute of Environmental Health Sciences, part of the National Institutes of Health.