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TDMS Study 05156-06 Pathology Tables

NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25

                                                           CORE STUDY




       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




































                                                              Page   1

NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 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                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Clear Cell Focus                     |                                                                          |             
      Eosinophilic Focus                   |                   2           3  3  3     X           X                  |             
      Infiltration Cellular, Lymphocyte    |                                  2     1                                 |             
      Inflammation, Chronic                |          2     2           1                                             |             
      Karyomegaly                          |          2     3                                                         |             
      Necrosis, Focal                      |                                                                2         |             
      Necrosis                             |                2                                                         |             
      Regeneration                         |                                                                          |             
      Oval Cell, Hyperplasia               |                                                                          |             
                                            __________________________________________________________________________|             
   Mesentery                               |       +              +     +                                   +     +   |             
      Angiectasis                          |                                                                          |             
      Fat, Necrosis                        |       3              3     3                                   3     3   |             
                                            __________________________________________________________________________|             
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Inflammation, Chronic                |                                                                          |             
      Acinus, Atrophy                      |                                                                          |             
      Duct, Cyst                           |                                                          2               |             
                                            __________________________________________________________________________|             
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hyperplasia, Squamous                |                                                                         2|             
                                            __________________________________________________________________________|             
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 CARDIOVASCULAR SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Mineralization                       |                                                                         2|             
      Artery, Inflammation, Chronic        |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM                          |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Angiectasis                          |                                                                         2|             
      Inflammation                         |                         1                                                |             
                                            __________________________________________________________________________|             
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Parathyroid Gland                       | +  +  M  M  M  M  +  M  M  M  +  +  +  +  +  +  +  +  M  M  +  +  M  +  +|             
                                            __________________________________________________________________________|             
   Pituitary Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  I  I  +  +  +  +  +  +  +  +  +  +|             
      Angiectasis                          |                                                                          |             
 _____________________________________________________________________________________________________________________|             
                                                             Page   2                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 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                   |                                                                          |             
                                           |                                                                          |             
      Pars Distalis, Angiectasis           |                                                                          |             
      Pars Distalis, Hyperplasia           |       4           1  2     1     1                                       |             
                                            __________________________________________________________________________|             
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Follicular Cell, Hyperplasia         |             3  3  1  2     2     1     1     1           1  1           2|             
 _____________________________________________________________________________________________________________________|             
 GENERAL BODY SYSTEM                       |                                                                          |             
                                           |                                                                          |             
    None                                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 GENITAL SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Clitoral Gland                          | +  +  +  +  +  +  +  +  M  +  +  M  +  +  +  +  +  +  M  +  +  M  M  +  M|             
      Cyst                                 |    3                                                                     |             
      Inflammation                         |    1                                                                     |             
                                            __________________________________________________________________________|             
   Ovary                                   | +  +  +  +  +  +  +  +  +  I  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Angiectasis                          |                                                                          |             
      Cyst                                 |                               2  3           3  3  2                 3   |             
                                            __________________________________________________________________________|             
   Uterus                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Angiectasis                          |                                                                          |             
      Hyperplasia, Cystic                  |    2  3     2  1  3  2  2     2  2  1  3  3  3  2  2  1  3  2  2  1  3   |             
      Thrombosis                           |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Lymph Node                              |       +  +                                                              +|             
                                            __________________________________________________________________________|             
   Lymph Node, Bronchial                   | +  M  +  M  +  M  M  +  +  +  M  M  +  +  M  +  +  +  +  +  M  +  +  +  M|             
      Hyperplasia, Lymphoid                |                                     2                                    |             
                                            __________________________________________________________________________|             
   Lymph Node, Mandibular                  | +  +  +  +  M  +  +  +  +  M  +  +  +  +  +  +  +  M  +  +  +  M  M  M  +|             
                                            __________________________________________________________________________|             
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  +  +  I  +  I  +  +  +  +  +  +  +  +  +  I  +  +|             
      Hyperplasia, Lymphoid                |                                                                          |             
      Infiltration Cellular, Histiocyte    |                                                                          |             
      Inflammation, Chronic                |                                                                          |             
                                            __________________________________________________________________________|             
   Lymph Node, Mediastinal                 | +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  M  M  +  +  +  M  +  +|             
      Hyperplasia, Lymphoid                |                                     2                                    |             
                                            __________________________________________________________________________|             
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hematopoietic Cell Proliferation     |                2  3                                                      |             
      Hyperplasia, Lymphoid                |                                                                          |             
                                            __________________________________________________________________________|             
   Thymus                                  | M  +  +  +  +  M  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hyperplasia, Lymphoid                |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 INTEGUMENTARY SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Mammary Gland                           | +  I  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M|             
      Hyperplasia                          |       3        2                                                         |             
                                            __________________________________________________________________________|             
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  I|             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM                    |                                                                          |             
                                           |                                                                          |             
 _____________________________________________________________________________________________________________________|             
                                                             Page   3                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 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|             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM - cont             |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Fibrous Osteodystrophy               |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 NERVOUS SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Spinal Cord                             |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 RESPIRATORY SYSTEM                        |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hemorrhage                           |                                                                          |             
      Infiltration Cellular, Focal,        |                                                                          |             
          Histiocyte                       |             1                                                            |             
      Alveolar Epithelium, Hyperplasia     |                                                                          |             
                                            __________________________________________________________________________|             
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Olfactory Epithelium, Degeneration,  |                                                                          |             
           Hyaline                         |                                        2        1                        |             
      Respiratory Epithelium, Degeneration,|                                                                          |             
           Hyaline                         |          1                 2  2  1              2  1  2  1  1  2  1      |             
                                            __________________________________________________________________________|             
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 SPECIAL SENSES SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Eye                                     |                                                                          |             
      Degeneration                         |                                                                          |             
                                            __________________________________________________________________________|             
   Harderian Gland                         | +                                                                        |             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Cyst                                 |       2                                                                  |             
      Infiltration Cellular, Mixed Cell    |                   2                                                      |             
      Nephropathy                          |                            1  1                                          |             
                                            __________________________________________________________________________|             
   Urinary Bladder                         | +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
                                                             Page   4                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 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        |
      Clear Cell Focus                     |                            X                             X               |      2     |
      Eosinophilic Focus                   |          X                                                     X     X   |      9  2.8|
      Infiltration Cellular, Lymphocyte    |       2                                                                  |      3  1.7|
      Inflammation, Chronic                |          1                          2                    2               |      6  1.7|
      Karyomegaly                          |                                     3                    3               |      4  2.8|
      Necrosis, Focal                      |                                           1  1                           |      3  1.3|
      Necrosis                             |                                                                          |      1  2.0|
      Regeneration                         |                                     2                                    |      1  2.0|
      Oval Cell, Hyperplasia               |                                     2                    2               |      2  2.0|
                                            __________________________________________________________________________|____________|
   Mesentery                               |                         +        +     +           +        +            |  10        |
      Angiectasis                          |                         3                                                |      1  3.0|
      Fat, Necrosis                        |                                  4     2                                 |      7  3.0|
                                            __________________________________________________________________________|____________|
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Inflammation, Chronic                |          3                                                               |      1  3.0|
      Acinus, Atrophy                      |                                  4                                       |      1  4.0|
      Duct, Cyst                           |                                                                          |      1  2.0|
                                            __________________________________________________________________________|____________|
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hyperplasia, Squamous                |                                                                          |      1  2.0|
                                            __________________________________________________________________________|____________|
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 CARDIOVASCULAR SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Mineralization                       |                                                                          |      1  2.0|
      Artery, Inflammation, Chronic        |    2                                                                     |      1  2.0|
 _____________________________________________________________________________________________________________________|            |
 ENDOCRINE SYSTEM                          |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Angiectasis                          |                                                                          |      1  2.0|
      Inflammation                         |                                                                          |      1  1.0|
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page   5                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 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                   |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Parathyroid Gland                       | M  +  M  M  +  +  +  M  +  M  +  M  M  M  +  M  M  M  +  +  M  +  M  M  M|  25        |
                                            __________________________________________________________________________|____________|
   Pituitary Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
      Angiectasis                          |                   2                                2                     |      2  2.0|
      Pars Distalis, Angiectasis           |                2                                                         |      1  2.0|
      Pars Distalis, Hyperplasia           |       1  1     2  1                    1        2              3         |     12  1.7|
                                            __________________________________________________________________________|____________|
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Follicular Cell, Hyperplasia         |          2  1     2  1     1           1     1                       1  1|     20  1.5|
 _____________________________________________________________________________________________________________________|            |
 GENERAL BODY SYSTEM                       |                                                                          |            |
                                           |                                                                          |            |
    None                                   |                                                                          |            |
 _____________________________________________________________________________________________________________________|            |
 GENITAL SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Clitoral Gland                          | +  +  +  +  +  +  M  +  +  +  M  +  +  +  +  +  M  +  +  +  +  +  +  +  +|  41        |
      Cyst                                 |                                                                          |      1  3.0|
      Inflammation                         |                                                                          |      1  1.0|
                                            __________________________________________________________________________|____________|
   Ovary                                   | +  +  +  +  +  +  I  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
      Angiectasis                          |                                                                4         |      1  4.0|
      Cyst                                 |                                        2  2  2                           |      9  2.4|
                                            __________________________________________________________________________|____________|
   Uterus                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Angiectasis                          |                                                                         2|      1  2.0|
      Hyperplasia, Cystic                  | 1  2  1  3  1  2  2  1  2                 2  2  2     3  1  3           2|     37  2.0|
      Thrombosis                           |                                                       3                  |      1  3.0|
 _____________________________________________________________________________________________________________________|            |
 HEMATOPOIETIC SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Lymph Node                              |                                                                          |   3        |
                                            __________________________________________________________________________|____________|
   Lymph Node, Bronchial                   | +  M  M  +  +  +  +  +  +  +  M  M  M  M  M  +  +  +  M  +  +  M  M  M  +|  30        |
      Hyperplasia, Lymphoid                |                                                                          |      1  2.0|
                                            __________________________________________________________________________|____________|
   Lymph Node, Mandibular                  | +  +  M  +  +  +  M  +  +  M  M  M  +  +  +  +  +  +  +  +  M  M  +  +  +|  37        |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  I  +  +  +  +  +  +  +  +  +  +|  46        |
      Hyperplasia, Lymphoid                |                                                             4            |      1  4.0|
      Infiltration Cellular, Histiocyte    |                                  4                                       |      1  4.0|
      Inflammation, Chronic                |          3                                                               |      1  3.0|
                                            __________________________________________________________________________|____________|
   Lymph Node, Mediastinal                 | M  +  +  +  M  M  M  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +|  41        |
      Hyperplasia, Lymphoid                |                         2  2                                             |      3  2.0|
                                            __________________________________________________________________________|____________|
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hematopoietic Cell Proliferation     |       3                                                                  |      3  2.7|
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page   6                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 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               |                                                                          |            |
                                           |                                                                          |            |
      Hyperplasia, Lymphoid                |                                                             4            |      1  4.0|
                                            __________________________________________________________________________|____________|
   Thymus                                  | +  +  +  M  +  +  +  +  +  +  +  +  M  M  +  +  +  +  +  M  +  M  +  +  M|  41        |
      Hyperplasia, Lymphoid                |                            2                                             |      1  2.0|
 _____________________________________________________________________________________________________________________|            |
 INTEGUMENTARY SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Mammary Gland                           | +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  47        |
      Hyperplasia                          |                                                          3               |      3  2.7|
                                            __________________________________________________________________________|____________|
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
 _____________________________________________________________________________________________________________________|            |
 MUSCULOSKELETAL SYSTEM                    |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Fibrous Osteodystrophy               |                                                 4     1                  |      2  2.5|
 _____________________________________________________________________________________________________________________|            |
 NERVOUS SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Spinal Cord                             |                                                                         +|   1        |
 _____________________________________________________________________________________________________________________|            |
 RESPIRATORY SYSTEM                        |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hemorrhage                           |                                                       2           2      |      2  2.0|
      Infiltration Cellular, Focal,        |                                                                          |            |
          Histiocyte                       |                                                                         3|      2  2.0|
      Alveolar Epithelium, Hyperplasia     |                               1                       2                  |      2  1.5|
                                            __________________________________________________________________________|____________|
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Olfactory Epithelium, Degeneration,  |                                                                          |            |
           Hyaline                         |                                                             2            |      3  1.7|
      Respiratory Epithelium, Degeneration,|                                                                          |            |
           Hyaline                         |       2  2  2     1        1        1  1  1  2                           |     20  1.5|
                                            __________________________________________________________________________|____________|
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 SPECIAL SENSES SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Eye                                     |                                                       +                  |   1        |
      Degeneration                         |                                                       4                  |      1  4.0|
                                            __________________________________________________________________________|____________|
   Harderian Gland                         |                                                       +                  |   2        |
 _____________________________________________________________________________________________________________________|            |
 URINARY SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Cyst                                 |                                                                          |      1  2.0|
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page   7                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 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|            |
 __________________________________________________________________________________________________________________________________ 
 URINARY SYSTEM - cont                     |                                                                          |            |
                                           |                                                                          |            |
      Infiltration Cellular, Mixed Cell    |                            2              2                              |      3  2.0|
      Nephropathy                          |       1                                                  1        1      |      5  1.0|
                                            __________________________________________________________________________|____________|
   Urinary Bladder                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +|  48        |
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page   8                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 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                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Basophilic Focus                     |                               X                                          |             
      Clear Cell Focus                     |                                                                          |             
      Eosinophilic Focus                   |                X                    X                          X         |             
      Hematopoietic Cell Proliferation     |                                                                          |             
      Hemorrhage                           |          2                                                               |             
      Infiltration Cellular, Lymphocyte    |                                     4                    2               |             
      Infiltration Cellular, Mixed Cell    |                                                                          |             
      Inflammation, Chronic                |                                                                         1|             
      Karyomegaly                          |                                                                         2|             
      Necrosis, Focal                      |                                                                         1|             
      Vacuolization Cytoplasmic            |                                                                          |             
      Oval Cell, Hyperplasia               |                                                                         2|             
                                            __________________________________________________________________________|             
   Mesentery                               |       +           +  +  +        +                                +      |             
      Infiltration Cellular, Lymphocyte    |                                                                   2      |             
      Inflammation, Chronic                |                                                                          |             
      Fat, Necrosis                        |       3           4              3                                       |             
                                            __________________________________________________________________________|             
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Inflammation, Chronic                |                                                                          |             
      Acinus, Atrophy                      |                                                                   4      |             
      Duct, Cyst                           |                                                                          |             
                                            __________________________________________________________________________|             
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Cyst                                 |                                                                          |             
      Hyperplasia, Squamous                |       2                                2              3                  |             
      Inflammation                         |                                        2              2                  |             
                                            __________________________________________________________________________|             
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 CARDIOVASCULAR SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM                          |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Degeneration, Cystic, Focal          |                                                                          |             
                                            __________________________________________________________________________|             
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
                                                             Page   9                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 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|             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM - cont                   |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Parathyroid Gland                       | I  M  M  +  M  +  M  +  M  M  +  M  +  +  +  +  M  +  M  M  M  M  M  +  +|             
                                            __________________________________________________________________________|             
   Pituitary Gland                         | +  +  +  I  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Angiectasis                          |             2  2  2           2                                          |             
      Pars Distalis, Hyperplasia           |                2                                                         |             
                                            __________________________________________________________________________|             
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  I  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Follicular Cell, Hyperplasia         | 1  2  1           2                       1  1     2  2                 3|             
 _____________________________________________________________________________________________________________________|             
 GENERAL BODY SYSTEM                       |                                                                          |             
                                           |                                                                          |             
    None                                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 GENITAL SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Clitoral Gland                          | +  +  +  +  +  M  +  M  +  M  +  +  +  +  +  +  +  M  M  +  +  +  +  +  +|             
      Inflammation                         |                                                 1                        |             
                                            __________________________________________________________________________|             
   Ovary                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  I|             
      Angiectasis                          |          3                                                               |             
      Cyst                                 |       2        2     2        2                 3  3                     |             
      Thrombosis                           |                                                                          |             
                                            __________________________________________________________________________|             
   Uterus                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Angiectasis                          |                                                          3               |             
      Hydrometra                           |          3                                                           3   |             
      Hyperplasia, Cystic                  | 2  2  1  3     2  2  2  2  2  3  2     2  2  1  3  2  2     2  2  1  2   |             
      Inflammation, Suppurative            |                                                                          |             
      Cervix, Hemorrhage                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Lymph Node                              |                                              +                           |             
      Hyperplasia, Lymphoid                |                                                                          |             
      Renal, Hyperplasia, Lymphoid         |                                                                          |             
                                            __________________________________________________________________________|             
   Lymph Node, Bronchial                   | +  M  M  +  +  +  M  M  M  +  +  +  +  M  M  +  +  +  M  +  M  M  +  +  +|             
      Hyperplasia, Lymphoid                |                                                                         3|             
                                            __________________________________________________________________________|             
   Lymph Node, Mandibular                  | +  +  M  +  +  +  +  M  +  +  +  +  M  M  +  +  +  +  +  M  +  +  +  +  +|             
      Hyperplasia, Lymphoid                |                                                                3         |             
                                            __________________________________________________________________________|             
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  M  +  +  +  +  +  +  I  +  +  +  +  +  M  +  +  +  +|             
      Hyperplasia, Lymphoid                | 2              3                                         4     3         |             
      Necrosis                             |                         3                                                |             
                                            __________________________________________________________________________|             
   Lymph Node, Mediastinal                 | +  +  +  +  M  +  +  M  +  M  +  +  M  +  +  +  M  M  M  +  M  +  +  M  +|             
      Hyperplasia, Lymphoid                |    2                                                           3        3|             
                                            __________________________________________________________________________|             
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hematopoietic Cell Proliferation     | 3              2     3  3                 3  3        2                  |             
      Hyperplasia, Lymphoid                |                   2                 3                          4        3|             
                                            __________________________________________________________________________|             
   Thymus                                  | +  +  +  +  +  +  +  M  +  +  +  +  +  M  +  +  +  +  +  M  M  +  +  +  M|             
      Hyperplasia, Lymphoid                |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 INTEGUMENTARY SYSTEM                      |                                                                          |             
 _____________________________________________________________________________________________________________________|             
                                                             Page  10                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 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|             
 _____________________________________________________________________________________________________________________|             
 INTEGUMENTARY SYSTEM - cont               |                                                                          |             
                                           |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Mammary Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hyperplasia                          |                                                                         2|             
                                            __________________________________________________________________________|             
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Inflammation, Chronic                |                                                                          |             
      Ulcer                                |                      3                                                   |             
      Subcutaneous Tissue, Inflammation,   |                                                                          |             
           Chronic                         |                         3                                                |             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM                    |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Fibrous Osteodystrophy               |                                                                   3      |             
                                            __________________________________________________________________________|             
   Skeletal Muscle                         |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 NERVOUS SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 RESPIRATORY SYSTEM                        |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Larynx                                  | +  +  +  +  +  +  +  +  I  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Metaplasia, Squamous                 |    1  1  1  1        1     1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1|             
                                            __________________________________________________________________________|             
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hemorrhage                           |                         3                                                |             
      Infiltration Cellular, Focal,        |                                                                          |             
          Histiocyte                       |                                  2           2              1  3         |             
      Alveolar Epithelium, Hyperplasia     |                2                                                         |             
      Bronchus, Vacuolization Cytoplasmic  | 1                                               1                        |             
                                            __________________________________________________________________________|             
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Inflammation, Suppurative            |                                                                          |             
      Olfactory Epithelium, Atrophy        |                                                                          |             
      Olfactory Epithelium, Degeneration,  |                                                                          |             
           Hyaline                         |             1                                                            |             
      Olfactory Epithelium, Metaplasia     |                                     2                                    |             
      Respiratory Epithelium, Degeneration,|                                                                          |             
           Hyaline                         |    1     3           2     1  2  1           1           2     1         |             
                                            __________________________________________________________________________|             
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 SPECIAL SENSES SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Harderian Gland                         |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Infiltration Cellular, Mixed Cell    | 3                                                                        |             
      Inflammation, Chronic                |                                                                          |             
      Metaplasia, Osseous                  |                                                                          |             
 _____________________________________________________________________________________________________________________|             
                                                             Page  11                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 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|             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM - cont                     |                                                                          |             
                                           |                                                                          |             
      Nephropathy                          |                            1                          1     1            |             
                                            __________________________________________________________________________|             
   Urinary Bladder                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +|             
      Edema                                |                         3                                                |             
 _____________________________________________________________________________________________________________________|             
                                                             Page  12                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 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        |
                                            __________________________________________________________________________|____________|
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Basophilic Focus                     |                                                                          |      1     |
      Clear Cell Focus                     | X                                                                        |      1     |
      Eosinophilic Focus                   |                         X                 X     X                    X   |      7     |
      Hematopoietic Cell Proliferation     |                                                                      1   |      1  1.0|
      Hemorrhage                           |                                                                          |      1  2.0|
      Infiltration Cellular, Lymphocyte    |                                                                          |      2  3.0|
      Infiltration Cellular, Mixed Cell    |          3                                                               |      1  3.0|
      Inflammation, Chronic                |                                                                          |      1  1.0|
      Karyomegaly                          |                                                                      1   |      2  1.5|
      Necrosis, Focal                      |                                                                          |      1  1.0|
      Vacuolization Cytoplasmic            |                   3                                                      |      1  3.0|
      Oval Cell, Hyperplasia               |                                                                          |      1  2.0|
                                            __________________________________________________________________________|____________|
   Mesentery                               |                +     +  +              +                          +  +   |  12        |
      Infiltration Cellular, Lymphocyte    |                                                                          |      1  2.0|
      Inflammation, Chronic                |                                                                      4   |      1  4.0|
      Fat, Necrosis                        |                      3  3              3                          3  4   |      8  3.3|
                                            __________________________________________________________________________|____________|
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Inflammation, Chronic                |                                                                      3   |      1  3.0|
      Acinus, Atrophy                      |                                                       4                  |      2  4.0|
      Duct, Cyst                           |                                                       4              4   |      2  4.0|
                                            __________________________________________________________________________|____________|
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Cyst                                 |                         3                                                |      1  3.0|
      Hyperplasia, Squamous                |                                                                          |      3  2.3|
      Inflammation                         |                                                                          |      2  2.0|
                                            __________________________________________________________________________|____________|
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 CARDIOVASCULAR SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 ENDOCRINE SYSTEM                          |                                                                          |            |
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  13                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 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                   |                                                                          |            |
                                           |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Degeneration, Cystic, Focal          |                            2                                             |      1  2.0|
                                            __________________________________________________________________________|____________|
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Parathyroid Gland                       | +  +  M  M  M  +  +  M  M  M  +  +  +  +  M  +  M  M  M  +  +  M  M  M  +|  23        |
                                            __________________________________________________________________________|____________|
   Pituitary Gland                         | +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  I  +  +  +  +  +  +  +|  47        |
      Angiectasis                          |       3                                                                  |      5  2.2|
      Pars Distalis, Hyperplasia           |                                                                          |      1  2.0|
                                            __________________________________________________________________________|____________|
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Follicular Cell, Hyperplasia         |          1                 2  4  1        2           3  1  2            |     17  1.8|
 _____________________________________________________________________________________________________________________|            |
 GENERAL BODY SYSTEM                       |                                                                          |            |
                                           |                                                                          |            |
    None                                   |                                                                          |            |
 _____________________________________________________________________________________________________________________|            |
 GENITAL SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Clitoral Gland                          | +  +  +  +  M  +  +  +  +  +  +  +  M  +  M  +  +  +  +  M  +  +  +  +  M|  40        |
      Inflammation                         |                                                                          |      1  1.0|
                                            __________________________________________________________________________|____________|
   Ovary                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Angiectasis                          |                                                                          |      1  3.0|
      Cyst                                 |    2  2                    2  3           3              2               |     12  2.3|
      Thrombosis                           |                                                             3            |      1  3.0|
                                            __________________________________________________________________________|____________|
   Uterus                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Angiectasis                          |                                                                          |      1  3.0|
      Hydrometra                           |                                                    4                     |      3  3.3|
      Hyperplasia, Cystic                  | 2  2     2     2  3  3     2  2  2  3  2  2  2     3     2  2  2  2  2  4|     41  2.1|
      Inflammation, Suppurative            |                         3                                                |      1  3.0|
      Cervix, Hemorrhage                   |                                              3                           |      1  3.0|
 _____________________________________________________________________________________________________________________|            |
 HEMATOPOIETIC SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Lymph Node                              |       +        +     +           +           +                           |   6        |
      Hyperplasia, Lymphoid                |                                  4                                       |      1  4.0|
      Renal, Hyperplasia, Lymphoid         |       4                                                                  |      1  4.0|
                                            __________________________________________________________________________|____________|
   Lymph Node, Bronchial                   | M  M  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  M  +  +  M  +  +  +|  34        |
      Hyperplasia, Lymphoid                |                                  3                                       |      2  3.0|
                                            __________________________________________________________________________|____________|
   Lymph Node, Mandibular                  | +  M  +  M  +  +  M  +  +  +  +  M  +  M  +  M  +  +  +  +  +  +  M  +  M|  37        |
      Hyperplasia, Lymphoid                |                                                                          |      1  3.0|
                                            __________________________________________________________________________|____________|
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  M  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  45        |
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  14                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 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               |                                                                          |            |
                                           |                                                                          |            |
      Hyperplasia, Lymphoid                |                                  3                                       |      5  3.0|
      Necrosis                             |                                                                          |      1  3.0|
                                            __________________________________________________________________________|____________|
   Lymph Node, Mediastinal                 | +  +  +  +  M  +  M  +  M  +  +  +  M  +  M  +  +  +  +  +  +  +  +  +  +|  36        |
      Hyperplasia, Lymphoid                |       3                                4                                 |      5  3.0|
                                            __________________________________________________________________________|____________|
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hematopoietic Cell Proliferation     |                3        3                             2              3   |     11  2.7|
      Hyperplasia, Lymphoid                |       4                                                                  |      5  3.2|
                                            __________________________________________________________________________|____________|
   Thymus                                  | +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  44        |
      Hyperplasia, Lymphoid                |          4                                                               |      1  4.0|
 _____________________________________________________________________________________________________________________|            |
 INTEGUMENTARY SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Mammary Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hyperplasia                          |             1                                   2              1         |      4  1.5|
                                            __________________________________________________________________________|____________|
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Inflammation, Chronic                |                                           1                              |      1  1.0|
      Ulcer                                |                                                                          |      1  3.0|
      Subcutaneous Tissue, Inflammation,   |                                                                          |            |
           Chronic                         |                                                                          |      1  3.0|
 _____________________________________________________________________________________________________________________|            |
 MUSCULOSKELETAL SYSTEM                    |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Fibrous Osteodystrophy               |                                                                          |      1  3.0|
                                            __________________________________________________________________________|____________|
   Skeletal Muscle                         |                +                                                         |   1        |
 _____________________________________________________________________________________________________________________|            |
 NERVOUS SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 RESPIRATORY SYSTEM                        |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Metaplasia, Squamous                 | 1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1     1  1  1  1  1  1  1  1|     45  1.0|
                                            __________________________________________________________________________|____________|
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hemorrhage                           |                                                                          |      1  3.0|
      Infiltration Cellular, Focal,        |                                                                          |            |
          Histiocyte                       |                   1                                                      |      5  1.8|
      Alveolar Epithelium, Hyperplasia     |                         1                       1                        |      3  1.3|
      Bronchus, Vacuolization Cytoplasmic  |             1                          1  1                 1            |      6  1.0|
                                            __________________________________________________________________________|____________|
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Inflammation, Suppurative            |          1                                                               |      1  1.0|
      Olfactory Epithelium, Atrophy        |                                                    2     1               |      2  1.5|
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  15                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 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                 |                                                                          |            |
                                           |                                                                          |            |
      Olfactory Epithelium, Degeneration,  |                                                                          |            |
           Hyaline                         |                                                                          |      1  1.0|
      Olfactory Epithelium, Metaplasia     |                                                                          |      1  2.0|
      Respiratory Epithelium, Degeneration,|                                                                          |            |
           Hyaline                         |                      1     1        1     1           2           1     1|     16  1.4|
                                            __________________________________________________________________________|____________|
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 SPECIAL SENSES SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Harderian Gland                         |                                     +           +                        |   2        |
 _____________________________________________________________________________________________________________________|            |
 URINARY SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Infiltration Cellular, Mixed Cell    |                                                                          |      1  3.0|
      Inflammation, Chronic                |                                                                      1   |      1  1.0|
      Metaplasia, Osseous                  |                                                          1               |      1  1.0|
      Nephropathy                          |       1           1                                   1                  |      6  1.0|
                                            __________________________________________________________________________|____________|
   Urinary Bladder                         | +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  47        |
      Edema                                |                                                                          |      1  3.0|
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  16                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 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  +  +|             
      Inflammation                         |                                                                          |             
                                            __________________________________________________________________________|             
   Intestine Small, Duodenum               | +  +  +  +  +  +  A  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Jejunum                | +  +  +  +  +  +  A  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Ileum                  | +  +  +  +  +  +  A  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
      Peyer's Patch, Hyperplasia, Lymphoid |                                                                          |             
                                            __________________________________________________________________________|             
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Clear Cell Focus                     |                                                                          |             
      Cyst                                 |                                              2                           |             
      Eosinophilic Focus                   |          X                 X  3                                         X|             
      Infiltration Cellular, Lymphocyte    |                         2                                                |             
      Inflammation, Chronic                |                                                                          |             
      Mineralization                       |                                                                          |             
      Necrosis, Focal                      |                                              2                           |             
      Vacuolization Cytoplasmic, Diffuse   |                               2                                          |             
                                            __________________________________________________________________________|             
   Mesentery                               |                               +        +           +                     |             
      Fat, Necrosis                        |                               3        4           3                     |             
                                            __________________________________________________________________________|             
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +|             
      Infiltration Cellular, Lymphocyte    |    2                                                                     |             
      Duct, Cyst                           |                                                                          |             
                                            __________________________________________________________________________|             
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
      Hyperplasia, Squamous                |                3                                                         |             
                                            __________________________________________________________________________|             
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
 _____________________________________________________________________________________________________________________|             
 CARDIOVASCULAR SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Artery, Inflammation, Chronic        |             2                                                            |             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM                          |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
      Cyst, Focal                          |                                                                          |             
      Vacuolization Cytoplasmic            |                4                                                         |             
      Capsule, Hyperplasia                 |                      3                                                   |             
                                            __________________________________________________________________________|             
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
                                            __________________________________________________________________________|             
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +|             
                                            __________________________________________________________________________|             
   Parathyroid Gland                       | M  I  +  +  M  +  M  +  +  M  +  M  M  M  +  +  +  +  M  +  +  M  A  +  +|             
                                            __________________________________________________________________________|             
   Pituitary Gland                         | +  +  +  +  +  +  +  I  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
      Angiectasis                          |                                                                          |             
      Pars Distalis, Hyperplasia           |                               2     2              2  1     1            |             
 _____________________________________________________________________________________________________________________|             
                                                             Page  17                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 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|             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM - cont                   |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
      Cyst                                 |                                                                          |             
      Infiltration Cellular, Lymphocyte    |                                                                          |             
      Follicular Cell, Hyperplasia         | 3        3              1  2              1     1                       3|             
 _____________________________________________________________________________________________________________________|             
 GENERAL BODY SYSTEM                       |                                                                          |             
                                           |                                                                          |             
    None                                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 GENITAL SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Clitoral Gland                          | +  M  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Ovary                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
      Angiectasis                          |                      2                                                   |             
      Atrophy                              |                            2              2                              |             
      Cyst                                 | 2     2                       3  2           3  2                        |             
      Bilateral, Cyst                      |                                                                          |             
                                            __________________________________________________________________________|             
   Uterus                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
      Angiectasis                          |                                                                          |             
      Hydrometra                           |                            2                                             |             
      Hyperplasia, Cystic                  | 2  2  1     1  2  2  2        2  2  3  3  1  2  1  2  2     3        3  2|             
      Thrombosis                           |          3                                                               |             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
      Inflammation, Chronic                |                               2                                          |             
                                            __________________________________________________________________________|             
   Lymph Node                              |                      +                                                   |             
      Iliac, Ectasia                       |                                                                          |             
                                            __________________________________________________________________________|             
   Lymph Node, Bronchial                   | +  +  +  M  M  +  M  +  M  M  +  +  M  +  +  +  +  M  M  +  M  +  M  M  M|             
      Hyperplasia, Lymphoid                |                                           2                              |             
                                            __________________________________________________________________________|             
   Lymph Node, Mandibular                  | +  +  M  +  +  +  +  +  M  +  M  +  M  +  +  +  +  +  I  +  M  M  +  +  +|             
                                            __________________________________________________________________________|             
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
      Hyperplasia, Lymphoid                |          3                                2                              |             
                                            __________________________________________________________________________|             
   Lymph Node, Mediastinal                 | +  +  M  +  +  +  M  +  M  +  +  M  M  +  +  +  M  +  +  M  M  +  A  +  +|             
      Hyperplasia, Lymphoid                |                                           2                              |             
                                            __________________________________________________________________________|             
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +|             
      Hematopoietic Cell Proliferation     |                                     2  3     3                 4     2   |             
      Hyperplasia, Lymphoid                |                            3                                             |             
                                            __________________________________________________________________________|             
   Thymus                                  | +  +  +  +  +  +  +  +  M  +  M  +  +  M  +  +  +  M  +  +  +  +  A  +  +|             
      Necrosis                             |                                                          3               |             
 _____________________________________________________________________________________________________________________|             
 INTEGUMENTARY SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Mammary Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hyperplasia                          |       2                                                                  |             
                                            __________________________________________________________________________|             
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Inflammation, Suppurative            |                                                       3                  |             
 _____________________________________________________________________________________________________________________|             
                                                             Page  18                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 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|             
 _____________________________________________________________________________________________________________________|             
 INTEGUMENTARY SYSTEM - cont               |                                                                          |             
                                           |                                                                          |             
      Ulcer                                |                                        3                                 |             
      Subcutaneous Tissue, Hemorrhage      |                                                          3               |             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM                    |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Fibrous Osteodystrophy               |                                     2                                    |             
      Fracture                             |                                                       X                  |             
                                            __________________________________________________________________________|             
   Skeletal Muscle                         |                                                          +               |             
      Hemorrhage                           |                                                          2               |             
 _____________________________________________________________________________________________________________________|             
 NERVOUS SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 RESPIRATORY SYSTEM                        |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  I  +  +  +  +  A  +  +|             
      Metaplasia, Squamous                 | 1     1  1  1     1  1     1  1  1  1  1  1  1  1     1  1  1  1     1  1|             
                                            __________________________________________________________________________|             
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Infiltration Cellular, Focal,        |                                                                          |             
          Histiocyte                       |                   4                       2  2                           |             
      Inflammation, Chronic                |                                              2                           |             
      Bronchus, Vacuolization Cytoplasmic  | 1  1     1  1  1  1  1     1        1     1     1  1  1        1     1  1|             
                                            __________________________________________________________________________|             
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
      Hemorrhage                           |                                                       3                  |             
      Inflammation, Suppurative            |                            2                          2                  |             
      Olfactory Epithelium, Atrophy        | 1           1        1  1  1                                             |             
      Olfactory Epithelium, Degeneration,  |                                                                          |             
           Hyaline                         |       1                                                                  |             
      Olfactory Epithelium, Metaplasia     |                                        2                                 |             
      Respiratory Epithelium, Degeneration,|                                                                          |             
           Hyaline                         |    1        1  2     2     2     1           1                           |             
                                            __________________________________________________________________________|             
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
 _____________________________________________________________________________________________________________________|             
 SPECIAL SENSES SYSTEM                     |                                                                          |             
                                           |                                                                          |             
    None                                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Infiltration Cellular, Mixed Cell    |                                                    2                     |             
      Inflammation, Chronic                |             1                                                            |             
      Metaplasia, Osseous                  |                                                                          |             
      Nephropathy                          | 1                       2           1     1  2                           |             
                                            __________________________________________________________________________|             
   Urinary Bladder                         | +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  I|             
 _____________________________________________________________________________________________________________________|             
                                                             Page  19                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 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        |
      Inflammation                         |                                     3                                    |      1  3.0|
                                            __________________________________________________________________________|____________|
   Intestine Small, Duodenum               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  47        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Jejunum                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  47        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Ileum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  47        |
      Peyer's Patch, Hyperplasia, Lymphoid |                                                                4         |      1  4.0|
                                            __________________________________________________________________________|____________|
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Clear Cell Focus                     |                                           X                              |      1     |
      Cyst                                 |                                                                          |      1  2.0|
      Eosinophilic Focus                   |                      X  X                       X     X                  |      8  3.0|
      Infiltration Cellular, Lymphocyte    |                                                                          |      1  2.0|
      Inflammation, Chronic                |                                                       1                  |      1  1.0|
      Mineralization                       |                                     3                                    |      1  3.0|
      Necrosis, Focal                      |                                     4                                    |      2  3.0|
      Vacuolization Cytoplasmic, Diffuse   |                                                                          |      1  2.0|
                                            __________________________________________________________________________|____________|
   Mesentery                               |                +        +           +        +                       +   |   8        |
      Fat, Necrosis                        |                3        3                    2                       3   |      7  3.0|
                                            __________________________________________________________________________|____________|
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Infiltration Cellular, Lymphocyte    |                                                                          |      1  2.0|
      Duct, Cyst                           |                                        3                                 |      1  3.0|
                                            __________________________________________________________________________|____________|
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Hyperplasia, Squamous                |                                                                          |      1  3.0|
                                            __________________________________________________________________________|____________|
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
 _____________________________________________________________________________________________________________________|            |
 CARDIOVASCULAR SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Artery, Inflammation, Chronic        |                                                                          |      1  2.0|
 _____________________________________________________________________________________________________________________|            |
 ENDOCRINE SYSTEM                          |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Cyst, Focal                          |                         4                                                |      1  4.0|
      Vacuolization Cytoplasmic            |                                                                          |      1  4.0|
      Capsule, Hyperplasia                 |                                                                          |      1  3.0|
                                            __________________________________________________________________________|____________|
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  20                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 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                   |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Parathyroid Gland                       | +  +  +  +  +  +  +  M  M  +  +  +  M  M  M  M  +  M  M  +  M  M  +  +  M|  28        |
                                            __________________________________________________________________________|____________|
   Pituitary Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +|  47        |
      Angiectasis                          |                                                                2         |      1  2.0|
      Pars Distalis, Hyperplasia           |    3                                   1                                 |      7  1.7|
                                            __________________________________________________________________________|____________|
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Cyst                                 |                      3                                                   |      1  3.0|
      Infiltration Cellular, Lymphocyte    |                      2                                                   |      1  2.0|
      Follicular Cell, Hyperplasia         |    2           2     3        2           2  2                 2         |     14  2.1|
 _____________________________________________________________________________________________________________________|            |
 GENERAL BODY SYSTEM                       |                                                                          |            |
                                           |                                                                          |            |
    None                                   |                                                                          |            |
 _____________________________________________________________________________________________________________________|            |
 GENITAL SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Clitoral Gland                          | +  +  +  +  +  +  M  M  M  +  +  M  +  M  +  +  +  +  +  +  +  +  +  +  +|  43        |
                                            __________________________________________________________________________|____________|
   Ovary                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Angiectasis                          |                                                                          |      1  2.0|
      Atrophy                              |                                                                          |      2  2.0|
      Cyst                                 |          3  3     2  2     3                 3  3  2        2           3|     16  2.5|
      Bilateral, Cyst                      |                               3                                          |      1  3.0|
                                            __________________________________________________________________________|____________|
   Uterus                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Angiectasis                          |                                              4                           |      1  4.0|
      Hydrometra                           |                                     3                                3   |      3  2.7|
      Hyperplasia, Cystic                  | 1  3  1        2  2  1     2  2  1     2  1  3  2  3     3  2  2  2     1|     38  1.9|
      Thrombosis                           |                                                                          |      1  3.0|
 _____________________________________________________________________________________________________________________|            |
 HEMATOPOIETIC SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Inflammation, Chronic                |                                                                          |      1  2.0|
                                            __________________________________________________________________________|____________|
   Lymph Node                              |             +                                                  +         |   3        |
      Iliac, Ectasia                       |                                                                2         |      1  2.0|
                                            __________________________________________________________________________|____________|
   Lymph Node, Bronchial                   | M  M  M  M  +  M  +  +  +  +  +  M  M  +  +  +  +  M  M  +  +  +  M  M  +|  27        |
      Hyperplasia, Lymphoid                |                                                                         2|      2  2.0|
                                            __________________________________________________________________________|____________|
   Lymph Node, Mandibular                  | +  M  +  M  +  +  +  +  +  +  +  M  M  +  +  +  +  M  +  +  M  +  +  +  M|  36        |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  M  +  +  +  +  M  +|  46        |
      Hyperplasia, Lymphoid                |                                                                          |      2  2.5|
                                            __________________________________________________________________________|____________|
   Lymph Node, Mediastinal                 | M  +  M  M  +  +  M  M  M  M  +  M  M  +  +  M  +  +  +  M  M  M  +  +  +|  28        |
      Hyperplasia, Lymphoid                |                                                                          |      1  2.0|
                                            __________________________________________________________________________|____________|
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  21                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 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|            |
 __________________________________________________________________________________________________________________________________ 
 HEMATOPOIETIC SYSTEM - cont               |                                                                          |            |
                                           |                                                                          |            |
      Hematopoietic Cell Proliferation     |    3                                3        3                    2      |      9  2.8|
      Hyperplasia, Lymphoid                |                                                                          |      1  3.0|
                                            __________________________________________________________________________|____________|
   Thymus                                  | +  +  +  M  M  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  M  +|  41        |
      Necrosis                             |                                                                          |      1  3.0|
 _____________________________________________________________________________________________________________________|            |
 INTEGUMENTARY SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Mammary Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hyperplasia                          |                            2                                             |      2  2.0|
                                            __________________________________________________________________________|____________|
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Inflammation, Suppurative            |                                                                          |      1  3.0|
      Ulcer                                |                                                                          |      1  3.0|
      Subcutaneous Tissue, Hemorrhage      |                                                                          |      1  3.0|
 _____________________________________________________________________________________________________________________|            |
 MUSCULOSKELETAL SYSTEM                    |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Fibrous Osteodystrophy               |                                                                          |      1  2.0|
      Fracture                             |                                                                          |      1     |
                                            __________________________________________________________________________|____________|
   Skeletal Muscle                         |                      +                                                   |   2        |
      Hemorrhage                           |                                                                          |      1  2.0|
 _____________________________________________________________________________________________________________________|            |
 NERVOUS SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 RESPIRATORY SYSTEM                        |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  I  +  +|  47        |
      Metaplasia, Squamous                 | 1     1  1     1  1  1  1  1  1  1  1  1  1  1  1  1  1        1     1  1|     40  1.0|
                                            __________________________________________________________________________|____________|
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Infiltration Cellular, Focal,        |                                                                          |            |
          Histiocyte                       |                                  3                 2  4                 3|      7  2.9|
      Inflammation, Chronic                |                                                                          |      1  2.0|
      Bronchus, Vacuolization Cytoplasmic  | 1  1  1  1  1  1        1     1     1  1     1     1     1     1     1   |     31  1.0|
                                            __________________________________________________________________________|____________|
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Hemorrhage                           |                                                                          |      1  3.0|
      Inflammation, Suppurative            |                                  1              1  2                     |      5  1.6|
      Olfactory Epithelium, Atrophy        |          1                 1     1  1                    1        1     1|     12  1.0|
      Olfactory Epithelium, Degeneration,  |                                                                          |            |
           Hyaline                         |                                                                         2|      2  1.5|
      Olfactory Epithelium, Metaplasia     |                                                                          |      1  2.0|
      Respiratory Epithelium, Degeneration,|                                                                          |            |
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  22                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 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|            |
 __________________________________________________________________________________________________________________________________ 
 RESPIRATORY SYSTEM - cont                 |                                                                          |            |
                                           |                                                                          |            |
           Hyaline                         |       1     1     1                       1  1                    2     2|     14  1.4|
                                            __________________________________________________________________________|____________|
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
 _____________________________________________________________________________________________________________________|            |
 SPECIAL SENSES SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
    None                                   |                                                                          |            |
 _____________________________________________________________________________________________________________________|            |
 URINARY SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Infiltration Cellular, Mixed Cell    |                                                                          |      1  2.0|
      Inflammation, Chronic                |                                                                          |      1  1.0|
      Metaplasia, Osseous                  |             2                                                            |      1  2.0|
      Nephropathy                          |                                  1                    1                  |      7  1.3|
                                            __________________________________________________________________________|____________|
   Urinary Bladder                         | +  +  +  +  +  +  +  +  +  I  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|  45        |
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  23                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 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  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Colon                  | +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Cecum                  | +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Duodenum               | +  +  +  +  +  +  +  +  +  A  A  +  A  +  +  +  A  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Jejunum                | +  +  +  +  +  +  +  +  +  A  A  +  A  +  +  +  A  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Ileum                  | +  +  +  +  +  +  +  +  +  A  A  +  A  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Clear Cell Focus                     |                X                                                         |             
      Clear Cell Focus, Multiple           |                      X                                                   |             
      Cyst                                 |                                                                      4   |             
      Eosinophilic Focus                   |             X  X                    X        X                           |             
      Eosinophilic Focus, Multiple         |                                                                          |             
      Hematopoietic Cell Proliferation     |                   2                                                      |             
      Infiltration Cellular, Lymphocyte    |                                                                   1      |             
      Inflammation, Chronic                |                            2                                             |             
      Karyomegaly                          |          2                                                               |             
      Necrosis, Focal                      |                                                                          |             
      Thrombosis                           |                                                                          |             
      Vacuolization Cytoplasmic, Diffuse   |    2                                                                     |             
      Serosa, Fibrosis                     |                                                                          |             
                                            __________________________________________________________________________|             
   Mesentery                               |                +  +                                   +                  |             
      Hemorrhage                           |                                                                          |             
      Fat, Necrosis                        |                4                                      3                  |             
                                            __________________________________________________________________________|             
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Acinus, Atrophy                      |             3                                            1               |             
                                            __________________________________________________________________________|             
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hyperplasia, Squamous                |                                  1                          3            |             
                                            __________________________________________________________________________|             
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 CARDIOVASCULAR SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Epicardium, Fibrosis                 |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM                          |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Accessory Adrenal Cortical Nodule    |    2                                                                     |             
      Inflammation                         |                                                                          |             
      Vacuolization Cytoplasmic            |                                                                          |             
                                            __________________________________________________________________________|             
   Adrenal Medulla                         | +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Parathyroid Gland                       | M  +  +  +  M  +  +  M  M  +  +  I  +  +  M  M  M  I  M  M  +  +  +  M  M|             
 _____________________________________________________________________________________________________________________|             
                                                             Page  24                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 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|             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM - cont                   |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Pituitary Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  I  +  +  +  +  +  +  +  +  +  +  +  +|             
      Angiectasis                          |                                                                          |             
      Pars Distalis, Hyperplasia           |                               2           2                 2            |             
                                            __________________________________________________________________________|             
   Thyroid Gland                           | +  +  +  +  +  +  +  I  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Inflammation                         |                                                                          |             
      Follicular Cell, Hyperplasia         |    2        2           2  2                                2            |             
 _____________________________________________________________________________________________________________________|             
 GENERAL BODY SYSTEM                       |                                                                          |             
                                           |                                                                          |             
    None                                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 GENITAL SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Clitoral Gland                          | +  M  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  M  M  +  M  +  +  M  +|             
                                            __________________________________________________________________________|             
   Ovary                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  I  +  +  +  +  +  +  +  +|             
      Cyst                                 | 2  2     3        2     3        3                 2     2  2            |             
                                            __________________________________________________________________________|             
   Uterus                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hydrometra                           |                                                                         3|             
      Hyperplasia, Cystic                  | 2  2  3  1  2  1  1  2  3     2  1     2  2  2     2  2     2  2     2   |             
      Inflammation                         |                                                 1                        |             
      Thrombosis                           |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Lymph Node                              |          +                                                               |             
                                            __________________________________________________________________________|             
   Lymph Node, Bronchial                   | +  +  M  M  +  +  +  M  +  M  M  +  +  +  +  +  +  M  +  M  +  +  M  +  +|             
      Hyperplasia, Lymphoid                |                                                                          |             
      Infiltration Cellular, Histiocyte    |                                                                          |             
                                            __________________________________________________________________________|             
   Lymph Node, Mandibular                  | M  +  +  +  I  +  M  M  M  +  +  +  +  M  M  M  +  M  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Lymph Node, Mesenteric                  | +  +  M  +  +  +  +  +  +  I  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Lymph Node, Mediastinal                 | M  +  +  +  M  +  +  +  M  M  +  +  +  +  M  M  +  +  M  +  M  +  +  +  M|             
      Hemorrhage                           |                   2                                                      |             
      Hyperplasia, Lymphoid                |                                                                   3      |             
                                            __________________________________________________________________________|             
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hematopoietic Cell Proliferation     |                   3                                                      |             
      Hyperplasia, Lymphoid                |                                                                          |             
                                            __________________________________________________________________________|             
   Thymus                                  | +  +  +  +  +  +  +  M  +  M  +  +  M  +  +  +  +  M  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 INTEGUMENTARY SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Mammary Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Ulcer                                |                                                                   3      |             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM                    |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Fibrous Osteodystrophy               |    2                             1           1        2                 4|             
 _____________________________________________________________________________________________________________________|             
                                                             Page  25                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 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|             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM - cont             |                                                                          |             
                                           |                                                                          |             
      Fracture                             |                                           X                              |             
      Maxilla, Inflammation, Chronic       |                                                          4               |             
                                            __________________________________________________________________________|             
   Skeletal Muscle                         |                                  +                                       |             
 _____________________________________________________________________________________________________________________|             
 NERVOUS SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hemorrhage                           |                                                                          |             
                                            __________________________________________________________________________|             
   Spinal Cord                             |       +                                                                  |             
      Degeneration                         |       2                                                                  |             
 _____________________________________________________________________________________________________________________|             
 RESPIRATORY SYSTEM                        |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Inflammation, Chronic                |                                                                          |             
      Metaplasia, Squamous                 | 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|             
                                            __________________________________________________________________________|             
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hemorrhage                           |                            4                       2                     |             
      Infiltration Cellular, Diffuse,      |                                                                          |             
          Histiocyte                       |                                                                   4      |             
      Infiltration Cellular, Focal,        |                                                                          |             
          Histiocyte                       | 3        2     2                       3     2  3        2               |             
      Inflammation, Chronic                |                               2                                          |             
      Alveolar Epithelium, Hyperplasia     | 2                                                        2        2      |             
      Bronchus, Vacuolization Cytoplasmic  | 2  1  1  1  1  1  1  1  1     1  1        1  1  1  1  1     1  1     1  1|             
      Capillary, Thrombosis, Diffuse       |                               2                                          |             
                                            __________________________________________________________________________|             
   Nose                                    | +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Inflammation, Chronic                |                                                                          |             
      Inflammation, Suppurative            |    2     1     2                                      1                  |             
      Olfactory Epithelium, Atrophy        | 1  1  1  2  1  2  2  1  1     2  1     2  2  1  1     1  1  1  1  2  1  1|             
      Olfactory Epithelium, Degeneration,  |                                                                          |             
           Hyaline                         |                                  1                                       |             
      Olfactory Epithelium, Hyperplasia    | 1  1     1  1     1     1     1  1  3     2     1  1     2  1        1  1|             
      Respiratory Epithelium, Degeneration,|                                                                          |             
           Hyaline                         |                1                                               1  1  2   |             
      Respiratory Epithelium, Metaplasia,  |                                                                          |             
           Squamous                        |                                                          4        1      |             
                                            __________________________________________________________________________|             
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 SPECIAL SENSES SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Harderian Gland                         |                                                                      +   |             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Cyst                                 |                                  3                                      2|             
      Infarct                              |                   3                                                      |             
 _____________________________________________________________________________________________________________________|             
                                                             Page  26                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 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|             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM - cont                     |                                                                          |             
                                           |                                                                          |             
      Infiltration Cellular, Mixed Cell    |                                                                          |             
      Mineralization                       |                                     2                                    |             
      Nephropathy                          |                                                    1        1            |             
      Pigmentation, Hemosiderin            |                                                                          |             
                                            __________________________________________________________________________|             
   Urinary Bladder                         | +  +  +  +  +  +  +  +  +  A  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
                                                             Page  27                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 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        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Colon                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  47        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Cecum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  47        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Duodenum               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  45        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Jejunum                | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  44        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Ileum                  | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  45        |
                                            __________________________________________________________________________|____________|
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  49        |
      Clear Cell Focus                     |                                                                          |      1     |
      Clear Cell Focus, Multiple           |                                                                          |      1     |
      Cyst                                 |                                                                          |      1  4.0|
      Eosinophilic Focus                   |       X     X     X                       X           X                  |      9     |
      Eosinophilic Focus, Multiple         |                            X                                             |      1     |
      Hematopoietic Cell Proliferation     |                                                                          |      1  2.0|
      Infiltration Cellular, Lymphocyte    |                                                                          |      1  1.0|
      Inflammation, Chronic                |                                  2                                       |      2  2.0|
      Karyomegaly                          |                                                                          |      1  2.0|
      Necrosis, Focal                      |                2     3                                                   |      2  2.5|
      Thrombosis                           |                4                                                         |      1  4.0|
      Vacuolization Cytoplasmic, Diffuse   |                                                                          |      1  2.0|
      Serosa, Fibrosis                     |                                                 2                        |      1  2.0|
                                            __________________________________________________________________________|____________|
   Mesentery                               |                            +                 +        +                 +|   7        |
      Hemorrhage                           |                                                       3                  |      1  3.0|
      Fat, Necrosis                        |                            4                 3                          4|      5  3.6|
                                            __________________________________________________________________________|____________|
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  49        |
      Acinus, Atrophy                      |                                        1                                 |      3  1.7|
                                            __________________________________________________________________________|____________|
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hyperplasia, Squamous                |                                           1                              |      3  1.7|
                                            __________________________________________________________________________|____________|
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 CARDIOVASCULAR SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Epicardium, Fibrosis                 |                                                 2                        |      1  2.0|
 _____________________________________________________________________________________________________________________|            |
 ENDOCRINE SYSTEM                          |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Accessory Adrenal Cortical Nodule    |                                                                          |      1  2.0|
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  28                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 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                   |                                                                          |            |
                                           |                                                                          |            |
      Inflammation                         |                                                             2            |      1  2.0|
      Vacuolization Cytoplasmic            |                      3                                                   |      1  3.0|
                                            __________________________________________________________________________|____________|
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Parathyroid Gland                       | M  +  +  +  I  +  M  M  +  M  +  +  M  +  +  +  +  +  M  +  I  +  M  M  M|  26        |
                                            __________________________________________________________________________|____________|
   Pituitary Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  48        |
      Angiectasis                          |                                           1  2                           |      2  1.5|
      Pars Distalis, Hyperplasia           |                                                                2  2  1   |      6  1.8|
                                            __________________________________________________________________________|____________|
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Inflammation                         |                                  2                                       |      1  2.0|
      Follicular Cell, Hyperplasia         |          2  1     1  3     1  2  2     4  2           1  1     1  1  4   |     19  1.9|
 _____________________________________________________________________________________________________________________|            |
 GENERAL BODY SYSTEM                       |                                                                          |            |
                                           |                                                                          |            |
    None                                   |                                                                          |            |
 _____________________________________________________________________________________________________________________|            |
 GENITAL SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Clitoral Gland                          | +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  M  +  +  +  +  +  +  M  +  M|  40        |
                                            __________________________________________________________________________|____________|
   Ovary                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  48        |
      Cyst                                 |          2        3  2           2                    1        1         |     15  2.1|
                                            __________________________________________________________________________|____________|
   Uterus                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  49        |
      Hydrometra                           |          4                                                               |      2  3.5|
      Hyperplasia, Cystic                  | 3  2  2     3  4  3  3     3  2  1  2  1  2  2        2  1        3     1|     37  2.1|
      Inflammation                         |                                                                3         |      2  2.0|
      Thrombosis                           |                4                                                         |      1  4.0|
 _____________________________________________________________________________________________________________________|            |
 HEMATOPOIETIC SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Lymph Node                              |    +                                            +        +               |   4        |
                                            __________________________________________________________________________|____________|
   Lymph Node, Bronchial                   | +  +  +  +  +  M  +  M  +  +  +  +  +  +  M  +  +  M  +  M  M  +  +  M  +|  35        |
      Hyperplasia, Lymphoid                | 3                                                     2           2      |      3  2.3|
      Infiltration Cellular, Histiocyte    | 3                                                                        |      1  3.0|
                                            __________________________________________________________________________|____________|
   Lymph Node, Mandibular                  | +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  M  M  +  +  +  M  +  +  +  M|  36        |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  A  +  +  M  +  +  +  +|  44        |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mediastinal                 | +  +  +  +  M  +  +  +  +  +  +  M  M  M  M  M  +  +  +  +  M  +  +  +  +|  34        |
      Hemorrhage                           |                                                                          |      1  2.0|
      Hyperplasia, Lymphoid                | 3                                                                 3      |      3  3.0|
                                            __________________________________________________________________________|____________|
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  49        |
      Hematopoietic Cell Proliferation     |                3                                                     3   |      3  3.0|
      Hyperplasia, Lymphoid                |                                        2                          3      |      2  2.5|
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  29                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 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               |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Thymus                                  | +  M  +  +  +  M  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  M  +|  41        |
 _____________________________________________________________________________________________________________________|            |
 INTEGUMENTARY SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Mammary Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Ulcer                                |                                                                          |      1  3.0|
 _____________________________________________________________________________________________________________________|            |
 MUSCULOSKELETAL SYSTEM                    |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Fibrous Osteodystrophy               |                                                                          |      5  2.0|
      Fracture                             |                                                                          |      1     |
      Maxilla, Inflammation, Chronic       |                                                                          |      1  4.0|
                                            __________________________________________________________________________|____________|
   Skeletal Muscle                         |                                                                          |   1        |
 _____________________________________________________________________________________________________________________|            |
 NERVOUS SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hemorrhage                           |                                                    3                     |      1  3.0|
                                            __________________________________________________________________________|____________|
   Spinal Cord                             |                                                                          |   1        |
      Degeneration                         |                                                                          |      1  2.0|
 _____________________________________________________________________________________________________________________|            |
 RESPIRATORY SYSTEM                        |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Inflammation, Chronic                |                2                                                         |      1  2.0|
      Metaplasia, Squamous                 | 1  1  1  1  1  2  1  1  1  1  1  1  1  1  1  1  1  1  2  1  1  1  2  1  1|     50  1.1|
                                            __________________________________________________________________________|____________|
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hemorrhage                           |                                                    3                 2   |      4  2.8|
      Infiltration Cellular, Diffuse,      |                                                                          |            |
          Histiocyte                       | 3  4                       2                                             |      4  3.3|
      Infiltration Cellular, Focal,        |                                                                          |            |
          Histiocyte                       |                                                    3     2              2|     10  2.4|
      Inflammation, Chronic                |                                                                          |      1  2.0|
      Alveolar Epithelium, Hyperplasia     |          2                                                              2|      5  2.0|
      Bronchus, Vacuolization Cytoplasmic  | 1     1  1  1  1  1  1  1  1  1  1  1  1  1  1  1     1  1  1  1  1  1  1|     43  1.0|
      Capillary, Thrombosis, Diffuse       |                                                                          |      1  2.0|
                                            __________________________________________________________________________|____________|
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  48        |
      Inflammation, Chronic                |                                           1                              |      1  1.0|
      Inflammation, Suppurative            |                                                                          |      4  1.5|
      Olfactory Epithelium, Atrophy        | 2  1  1  1  1  1  1  2  1  2  2  2  2  2  2  2  2     2  2  1  2  2  1  2|     46  1.5|
      Olfactory Epithelium, Degeneration,  |                                                                          |            |
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  30                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 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                 |                                                                          |            |
                                           |                                                                          |            |
           Hyaline                         |                                                             1            |      2  1.0|
      Olfactory Epithelium, Hyperplasia    |             1  1  2  1  1        1        1  2  2     1  2     1  1     1|     30  1.3|
      Respiratory Epithelium, Degeneration,|                                                                          |            |
           Hyaline                         |    1                          1     1  1        2              1     2   |     11  1.3|
      Respiratory Epithelium, Metaplasia,  |                                                                          |            |
           Squamous                        | 2     1                                                                  |      4  2.0|
                                            __________________________________________________________________________|____________|
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  49        |
 _____________________________________________________________________________________________________________________|            |
 SPECIAL SENSES SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Harderian Gland                         |                                                                          |   1        |
 _____________________________________________________________________________________________________________________|            |
 URINARY SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Cyst                                 |                                                                          |      2  2.5|
      Infarct                              |                                                                          |      1  3.0|
      Infiltration Cellular, Mixed Cell    |          2                          1                 2                  |      3  1.7|
      Mineralization                       |                                                                          |      1  2.0|
      Nephropathy                          |                                                                      1   |      3  1.0|
      Pigmentation, Hemosiderin            |                3                                                         |      1  3.0|
                                            __________________________________________________________________________|____________|
   Urinary Bladder                         | I  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +|  46        |
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  31                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 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|             
      Degeneration, Hyaline                |                                                                          |             
                                            __________________________________________________________________________|             
   Intestine Large, Colon                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Cecum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  A|             
                                            __________________________________________________________________________|             
   Intestine Small, Duodenum               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Jejunum                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Ileum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Basophilic Focus                     |                                                                          |             
      Eosinophilic Focus                   |                                  X              2        2           X   |             
      Eosinophilic Focus, Multiple         |                                                                   2      |             
      Infiltration Cellular, Lymphocyte    |                                                                          |             
      Inflammation, Chronic                | 1  1     1  1  1  1  2  1     1        1     2  1     1  2  2  3  2  2  1|             
      Karyomegaly                          | 3  3  3  3  3  2  2  2  3  2  2        2     3  2     3  2  1  3  3  2  2|             
      Mineralization                       |                                                                3         |             
      Necrosis, Focal                      |                      2                                                   |             
      Regeneration                         | 3  3  3  3  2  1  1  3  2     3        2     3        2  3  3  3  3     1|             
      Oval Cell, Hyperplasia               | 3  3  2  3  3  2  3  3  3  2  3        2     2  2     3  2  3  3  3  2  3|             
                                            __________________________________________________________________________|             
   Mesentery                               |                                              +  +              +         |             
      Inflammation, Chronic                |                                                 3                        |             
      Artery, Fibrosis                     |                                                                3         |             
      Fat, Necrosis                        |                                                 2                        |             
                                            __________________________________________________________________________|             
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +     +  +  +     +     +  +|             
                                            __________________________________________________________________________|             
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hyperplasia, Squamous                |             3                                                  2         |             
                                            __________________________________________________________________________|             
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 CARDIOVASCULAR SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Cardiomyopathy                       |                                                                          |             
      Atrium, Thrombosis                   |                4                                                         |             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM                          |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hyperplasia                          |                                                    1        2            |             
                                            __________________________________________________________________________|             
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +|             
      Hyperplasia                          |                                                                2         |             
                                            __________________________________________________________________________|             
   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  32                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 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                   |                                                                          |             
                                           |                                                                          |             
      Follicular Cell, Hyperplasia         |    1                 1                                                   |             
 _____________________________________________________________________________________________________________________|             
 GENERAL BODY SYSTEM                       |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Peritoneum                              |                                              +                           |             
                                            __________________________________________________________________________|             
   Tissue NOS                              |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 GENITAL SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Epididymis                              | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Granuloma Sperm                      |                                     3                                    |             
                                            __________________________________________________________________________|             
   Penis                                   |                            +                                             |             
      Inflammation, Chronic                |                            2                                             |             
                                            __________________________________________________________________________|             
   Preputial Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Cyst                                 |                                  3                                       |             
      Inflammation, Chronic                |          1              1     1           1                              |             
                                            __________________________________________________________________________|             
   Prostate                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +|             
      Inflammation                         |                                                                3         |             
                                            __________________________________________________________________________|             
   Seminal Vesicle                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Testes                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Lymph Node                              |                                                                          |             
                                            __________________________________________________________________________|             
   Lymph Node, Bronchial                   | +  M  M  +  M  M  +  I  M  M  M  M  +  M  +  M  M  M  M  +  +  +  +  M  M|             
      Infiltration Cellular, Histiocyte    |                                                                          |             
                                            __________________________________________________________________________|             
   Lymph Node, Mandibular                  | +  M  M  +  +  +  M  +  M  +  +  +  M  +  +  M  M  +  +  +  +  M  M  +  M|             
                                            __________________________________________________________________________|             
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hemorrhage                           |                                  3                                       |             
      Inflammation, Chronic                |                2                                                         |             
                                            __________________________________________________________________________|             
   Lymph Node, Mediastinal                 | +  M  +  M  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +|             
      Infiltration Cellular, Plasma Cell   |                                           3                              |             
      Infiltration Cellular, Histiocyte    |                                                                          |             
                                            __________________________________________________________________________|             
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Angiectasis                          |                                                                          |             
      Hematopoietic Cell Proliferation     |                      3                                3                  |             
                                            __________________________________________________________________________|             
   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                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Prepuce, Ulcer                       |                   4        3                                             |             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM                    |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Skeletal Muscle                         |                                              +                           |             
 _____________________________________________________________________________________________________________________|             
                                                             Page  33                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 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|             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM - cont             |                                                                          |             
                                           |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 NERVOUS SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 RESPIRATORY SYSTEM                        |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Foreign Body                         |                                                                          |             
                                            __________________________________________________________________________|             
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hemorrhage                           |             1                                                            |             
      Infiltration Cellular, Diffuse,      |                                                                          |             
          Histiocyte                       |                3                                                         |             
      Infiltration Cellular, Focal,        |                                                                          |             
          Histiocyte                       | 3        3                                3                    2        2|             
                                            __________________________________________________________________________|             
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Inflammation, Chronic                |          1                                                               |             
 _____________________________________________________________________________________________________________________|             
 SPECIAL SENSES SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Eye                                     |                            +                                             |             
      Degeneration                         |                            4                                             |             
                                            __________________________________________________________________________|             
   Harderian Gland                         |                            +                                             |             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Infiltration Cellular, Mixed Cell    |                                                             2  1        2|             
      Inflammation, Chronic                |                                                                          |             
      Nephropathy                          | 1              2     1           4           1        3  3               |             
                                            __________________________________________________________________________|             
   Urinary Bladder                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +|             
      Inflammation                         |                                                                3         |             
 _____________________________________________________________________________________________________________________|             
                                                             Page  34                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 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        |
      Degeneration, Hyaline                |                                              2                           |      1  2.0|
                                            __________________________________________________________________________|____________|
   Intestine Large, Colon                  | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Cecum                  | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  A  +  +  +  A  +  +|  45        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Duodenum               | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  A  A  +  +  +  A  +  +|  45        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Jejunum                | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  A  A  +  +  +  A  +  +|  45        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Ileum                  | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  A  A  +  +  +  A  +  +|  45        |
                                            __________________________________________________________________________|____________|
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Basophilic Focus                     |                                                 1                        |      1  1.0|
      Eosinophilic Focus                   |                   X              X              X                    X   |      8  2.0|
      Eosinophilic Focus, Multiple         |                                                                          |      1  2.0|
      Infiltration Cellular, Lymphocyte    |       3                                                                  |      1  3.0|
      Inflammation, Chronic                | 1  1     1              1  1     1  2        2  1  1        1  2  1  1   |     33  1.3|
      Karyomegaly                          | 3  1  2  3  1  1  2     3  3     3           2  3  3        1  2  3  3  1|     39  2.3|
      Mineralization                       |                                                                          |      1  3.0|
      Necrosis, Focal                      |                                     2     4                              |      3  2.7|
      Regeneration                         | 3  1  1  3              2  1     3  3        1  2  2           3  3  3   |     32  2.3|
      Oval Cell, Hyperplasia               | 3  2  3  3  1     2     3  3     3           3  3  3        1  2  3  3  1|     38  2.6|
                                            __________________________________________________________________________|____________|
   Mesentery                               |                                                                          |   3        |
      Inflammation, Chronic                |                                                                          |      1  3.0|
      Artery, Fibrosis                     |                                                                          |      1  3.0|
      Fat, Necrosis                        |                                                                          |      1  2.0|
                                            __________________________________________________________________________|____________|
   Pancreas                                | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
                                            __________________________________________________________________________|____________|
   Salivary Glands                         | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  46        |
                                            __________________________________________________________________________|____________|
   Stomach, Forestomach                    | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Hyperplasia, Squamous                |                                                 3        2               |      4  2.5|
                                            __________________________________________________________________________|____________|
   Stomach, Glandular                      | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +|  48        |
 _____________________________________________________________________________________________________________________|            |
 CARDIOVASCULAR SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Cardiomyopathy                       |                                                                         1|      1  1.0|
      Atrium, Thrombosis                   |                                                                          |      1  4.0|
 _____________________________________________________________________________________________________________________|            |
 ENDOCRINE SYSTEM                          |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Adrenal Cortex                          | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Hyperplasia                          |                         3                                                |      3  2.0|
                                            __________________________________________________________________________|____________|
   Adrenal Medulla                         | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  35                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 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                   |                                                                          |            |
                                           |                                                                          |            |
      Hyperplasia                          |                                                                          |      1  2.0|
                                            __________________________________________________________________________|____________|
   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        |
      Follicular Cell, Hyperplasia         |                                                                         2|      3  1.3|
 _____________________________________________________________________________________________________________________|            |
 GENERAL BODY SYSTEM                       |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Peritoneum                              |                                                                          |   1        |
                                            __________________________________________________________________________|____________|
   Tissue NOS                              |                                                          +               |   1        |
 _____________________________________________________________________________________________________________________|            |
 GENITAL SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Epididymis                              | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Granuloma Sperm                      |                                                                          |      1  3.0|
                                            __________________________________________________________________________|____________|
   Penis                                   |                                                                          |   1        |
      Inflammation, Chronic                |                                                                          |      1  2.0|
                                            __________________________________________________________________________|____________|
   Preputial Gland                         | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Cyst                                 |                                                                          |      1  3.0|
      Inflammation, Chronic                |       1  2  2                    3  3                    1  2     3     3|     13  1.8|
                                            __________________________________________________________________________|____________|
   Prostate                                | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  I  +  +  A  +  +|  46        |
      Inflammation                         |                                                                         3|      2  3.0|
                                            __________________________________________________________________________|____________|
   Seminal Vesicle                         | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
                                            __________________________________________________________________________|____________|
   Testes                                  | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
 _____________________________________________________________________________________________________________________|            |
 HEMATOPOIETIC SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone Marrow                             | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Lymph Node                              |                               +                                          |   1        |
                                            __________________________________________________________________________|____________|
   Lymph Node, Bronchial                   | +  +  M  M  M  +  M  M  M  +  +  +  M  +  M  I  M  +  +  +  +  +  M  M  I|  21        |
      Infiltration Cellular, Histiocyte    |                                  3                                       |      1  3.0|
                                            __________________________________________________________________________|____________|
   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        |
      Hemorrhage                           |                                  2                                       |      2  2.5|
      Inflammation, Chronic                |                                                                          |      1  2.0|
                                            __________________________________________________________________________|____________|
   Lymph Node, Mediastinal                 | +  +  +  +  +  +  +  A  +  +  +  +  +  +  M  +  +  +  M  +  +  +  +  +  +|  43        |
      Infiltration Cellular, Plasma Cell   |                                                                          |      1  3.0|
      Infiltration Cellular, Histiocyte    |       2                                      3                           |      2  2.5|
                                            __________________________________________________________________________|____________|
   Spleen                                  | +  +  +  +  +  +  +  A  +  +  +  +  +  +  M  +  +  +  A  +  +  +  +  +  +|  47        |
      Angiectasis                          |                               2                                          |      1  2.0|
      Hematopoietic Cell Proliferation     |       3  3  3                                3  3  3              3     3|     10  3.0|
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  36                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 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               |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   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        |
      Prepuce, Ulcer                       |                   3                                                     4|      4  3.5|
 _____________________________________________________________________________________________________________________|            |
 MUSCULOSKELETAL SYSTEM                    |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Skeletal Muscle                         |                                                                          |   1        |
 _____________________________________________________________________________________________________________________|            |
 NERVOUS SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 RESPIRATORY SYSTEM                        |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Larynx                                  | +  +  +  +  +  M  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
      Foreign Body                         |                                                          X               |      1     |
                                            __________________________________________________________________________|____________|
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hemorrhage                           |                                                                          |      1  1.0|
      Infiltration Cellular, Diffuse,      |                                                                          |            |
          Histiocyte                       |                                                                          |      1  3.0|
      Infiltration Cellular, Focal,        |                                                                          |            |
          Histiocyte                       |       3  2                       3              3                    3   |     10  2.7|
                                            __________________________________________________________________________|____________|
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Trachea                                 | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Inflammation, Chronic                |                                                                          |      1  1.0|
 _____________________________________________________________________________________________________________________|            |
 SPECIAL SENSES SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Eye                                     |                                                                          |   1        |
      Degeneration                         |                                                                          |      1  4.0|
                                            __________________________________________________________________________|____________|
   Harderian Gland                         |                   +                 +                       +            |   4        |
 _____________________________________________________________________________________________________________________|            |
 URINARY SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Kidney                                  | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Infiltration Cellular, Mixed Cell    |                   1              1                                       |      5  1.4|
      Inflammation, Chronic                |                                                                         4|      1  4.0|
      Nephropathy                          |       2     1                                1                       3   |     11  2.0|
                                            __________________________________________________________________________|____________|
   Urinary Bladder                         | +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  A  +  +  +  A  +  +|  46        |
      Inflammation                         |    4                                                                    4|      3  3.7|
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  37                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 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  +  +  +|             
      Degeneration, Hyaline                |                                                                          |             
                                            __________________________________________________________________________|             
   Intestine Large, Colon                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Cecum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Duodenum               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Jejunum                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Ileum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Clear Cell Focus                     |                   X                       X  X                           |             
      Eosinophilic Focus                   |             X                 X                                X         |             
      Eosinophilic Focus, Multiple         |                                                                          |             
      Inflammation, Chronic                | 1  1  1     1  2  2     1  1  2     1  1  2  3        2  2     1     2  1|             
      Karyomegaly                          | 3  2  2     3  3  3     3  3  3     3  2  3  2        3  4     3     3  3|             
      Necrosis, Focal                      | 2                                                     2              3   |             
      Regeneration                         |       2     2  2  3     2  3  3     2     2           2  3     3     3   |             
      Vacuolization Cytoplasmic, Diffuse   |                                                 3              2  2      |             
      Bile Duct, Hyperplasia               |                   1                 1                                    |             
      Oval Cell, Hyperplasia               | 3  2  2     3  3  3     3  3  3     3  2  3  2        3  3     3     3  3|             
                                            __________________________________________________________________________|             
   Mesentery                               |                                              +                       +   |             
      Artery, Inflammation, Chronic        |                                              3                           |             
      Fat, Necrosis                        |                                                                          |             
                                            __________________________________________________________________________|             
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Acinus, Atrophy                      |                         4                                                |             
                                            __________________________________________________________________________|             
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hyperplasia, Squamous                |                      1                                                   |             
                                            __________________________________________________________________________|             
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 CARDIOVASCULAR SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Cardiomyopathy                       |                                                                          |             
      Atrium, Thrombosis                   |                                                                         3|             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM                          |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hyperplasia                          |                                  1     1                                 |             
      Inflammation                         |                                              3                           |             
      Necrosis                             |                                              3                           |             
                                            __________________________________________________________________________|             
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Parathyroid Gland                       | M  +  +  +  M  +  +  +  M  +  +  +  +  +  +  M  M  +  +  +  +  +  M  +  +|             
                                            __________________________________________________________________________|             
   Pituitary Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
                                                             Page  38                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 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|             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM - cont                   |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Follicular Cell, Hyperplasia         |    3           3     1  1  1  1           2     1        1           1   |             
 _____________________________________________________________________________________________________________________|             
 GENERAL BODY SYSTEM                       |                                                                          |             
                                           |                                                                          |             
    None                                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 GENITAL SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Epididymis                              | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Mineralization                       |                                                                          |             
                                            __________________________________________________________________________|             
   Preputial Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Cyst                                 |                                              3                           |             
      Inflammation, Chronic                |       1                    2                    2     1        1        1|             
      Inflammation, Suppurative            |                                                                          |             
                                            __________________________________________________________________________|             
   Prostate                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Seminal Vesicle                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Testes                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Atrophy                              |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Lymph Node                              |                            +                                             |             
      Iliac, Hyperplasia, Lymphoid         |                            3                                             |             
      Renal, Hyperplasia, Lymphoid         |                            3                                             |             
                                            __________________________________________________________________________|             
   Lymph Node, Bronchial                   | +  M  M  M  +  M  +  M  +  +  M  +  M  M  +  +  M  M  M  +  +  M  +  +  M|             
      Infiltration Cellular, Plasma Cell   |                                                                          |             
                                            __________________________________________________________________________|             
   Lymph Node, Mandibular                  | M  +  +  M  +  M  +  M  +  M  +  M  M  M  M  M  M  +  M  +  M  M  M  M  M|             
                                            __________________________________________________________________________|             
   Lymph Node, Mesenteric                  | +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hemorrhage                           |                                                                          |             
      Hyperplasia, Lymphoid                |                                                                          |             
                                            __________________________________________________________________________|             
   Lymph Node, Mediastinal                 | +  +  +  M  M  +  M  +  +  +  +  +  M  +  +  +  M  M  +  M  M  +  M  M  +|             
      Hyperplasia, Lymphoid                |       3                                                                  |             
      Infiltration Cellular, Plasma Cell   |                                                                          |             
                                            __________________________________________________________________________|             
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hematopoietic Cell Proliferation     |                               3              3                           |             
      Hyperplasia, Lymphoid                |                   2        3                                             |             
                                            __________________________________________________________________________|             
   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                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Inflammation, Chronic                |                            3                                             |             
      Inflammation, Suppurative            |                                                                          |             
      Ulcer                                |                                                                          |             
      Prepuce, Inflammation, Chronic       |                         3                                                |             
 _____________________________________________________________________________________________________________________|             
                                                             Page  39                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 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|             
 _____________________________________________________________________________________________________________________|             
 INTEGUMENTARY SYSTEM - cont               |                                                                          |             
                                           |                                                                          |             
      Prepuce, Ulcer                       |                            3                                             |             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM                    |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 NERVOUS SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 RESPIRATORY SYSTEM                        |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Metaplasia, Squamous                 |    1  1        1  1  1  1  1  1  1     1  1  1  1        1  1  1  1  1  1|             
                                            __________________________________________________________________________|             
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Infiltration Cellular, Diffuse,      |                                                                          |             
          Histiocyte                       |                                                                         3|             
      Infiltration Cellular, Focal,        |                                                                          |             
          Histiocyte                       |       3     2                          3           2                     |             
      Inflammation, Chronic                |                                                                          |             
      Alveolar Epithelium, Hyperplasia     |    2                                                              2  2   |             
      Alveolar Epithelium, Goblet Cell,    |                                                                          |             
           Metaplasia, Focal               |                                                                          |             
      Bronchus, Vacuolization Cytoplasmic  |          1     1  1  1  1  1  1                 1     1  1               |             
                                            __________________________________________________________________________|             
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Inflammation, Suppurative            |                                     3                                    |             
                                            __________________________________________________________________________|             
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 SPECIAL SENSES SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Ear                                     |                                                                      +   |             
                                            __________________________________________________________________________|             
   Harderian Gland                         |       +                                                                 +|             
      Inflammation, Acute                  |                                                                         1|             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Cyst                                 |                                                                          |             
      Infiltration Cellular, Mixed Cell    |                                                                          |             
      Nephropathy                          | 3           3        2              1        2                          4|             
      Glomerulus, Amyloid Deposition       |                                                                          |             
                                            __________________________________________________________________________|             
   Urinary Bladder                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
                                                             Page  40                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 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        |
      Degeneration, Hyaline                |                                                             2            |      1  2.0|
                                            __________________________________________________________________________|____________|
   Intestine Large, Colon                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Cecum                  | +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Duodenum               | +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Jejunum                | +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +|  48        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Ileum                  | +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Clear Cell Focus                     |                                                                          |      3     |
      Eosinophilic Focus                   |                         X                    X                    X     X|      7     |
      Eosinophilic Focus, Multiple         |                                                                      X   |      1     |
      Inflammation, Chronic                | 2  2  2  1  1  1     1     2  2              2  1     1  1  2  2  2  2  2|     36  1.6|
      Karyomegaly                          | 3  3  3  3  2        2     3  3              3  2     3  3  3  3  3  3  3|     35  2.8|
      Necrosis, Focal                      |                                                                          |      3  2.3|
      Regeneration                         | 3  3  3  2  3        3     2  3              3  3     2  3  3  3  2  4  3|     30  2.7|
      Vacuolization Cytoplasmic, Diffuse   |                                                                          |      3  2.3|
      Bile Duct, Hyperplasia               |    2                                                                     |      3  1.3|
      Oval Cell, Hyperplasia               | 3  3  3  3  2  1     2     3  3              3  3     3  3  3  3  3  3  3|     36  2.8|
                                            __________________________________________________________________________|____________|
   Mesentery                               |                               +  +                                       |   4        |
      Artery, Inflammation, Chronic        |                                                                          |      1  3.0|
      Fat, Necrosis                        |                               2  2                                       |      2  2.0|
                                            __________________________________________________________________________|____________|
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Acinus, Atrophy                      |                                                                          |      1  4.0|
                                            __________________________________________________________________________|____________|
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hyperplasia, Squamous                |                                              4                           |      2  2.5|
                                            __________________________________________________________________________|____________|
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 CARDIOVASCULAR SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Cardiomyopathy                       |                   1     1           1                    1               |      4  1.0|
      Atrium, Thrombosis                   |                                                                3         |      2  3.0|
 _____________________________________________________________________________________________________________________|            |
 ENDOCRINE SYSTEM                          |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hyperplasia                          |                                                             1           1|      4  1.0|
      Inflammation                         |                                                                          |      1  3.0|
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  41                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 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|            |
 __________________________________________________________________________________________________________________________________ 
 ENDOCRINE SYSTEM - cont                   |                                                                          |            |
                                           |                                                                          |            |
      Necrosis                             |                                                                          |      1  3.0|
                                            __________________________________________________________________________|____________|
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Parathyroid Gland                       | +  +  M  +  +  M  +  M  +  +  +  +  M  M  +  M  +  +  +  +  +  M  I  +  +|  36        |
                                            __________________________________________________________________________|____________|
   Pituitary Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Follicular Cell, Hyperplasia         | 1  1  1                             3     2              1              4|     17  1.6|
 _____________________________________________________________________________________________________________________|            |
 GENERAL BODY SYSTEM                       |                                                                          |            |
                                           |                                                                          |            |
    None                                   |                                                                          |            |
 _____________________________________________________________________________________________________________________|            |
 GENITAL SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Epididymis                              | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Mineralization                       | 1                                                                       1|      2  1.0|
                                            __________________________________________________________________________|____________|
   Preputial Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Cyst                                 |    3                                                                     |      2  3.0|
      Inflammation, Chronic                |          2                 1  2        1  1           2                  |     12  1.4|
      Inflammation, Suppurative            |                3                 3                                       |      2  3.0|
                                            __________________________________________________________________________|____________|
   Prostate                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Seminal Vesicle                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Testes                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Atrophy                              | 2                                   2                                    |      2  2.0|
 _____________________________________________________________________________________________________________________|            |
 HEMATOPOIETIC SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Lymph Node                              |                                                                          |   1        |
      Iliac, Hyperplasia, Lymphoid         |                                                                          |      1  3.0|
      Renal, Hyperplasia, Lymphoid         |                                                                          |      1  3.0|
                                            __________________________________________________________________________|____________|
   Lymph Node, Bronchial                   | M  M  M  +  +  M  M  M  M  +  +  +  +  M  M  +  +  +  I  +  M  +  M  M  +|  24        |
      Infiltration Cellular, Plasma Cell   |                                  3                                       |      1  3.0|
                                            __________________________________________________________________________|____________|
   Lymph Node, Mandibular                  | +  M  M  +  M  +  M  +  +  +  +  M  +  +  +  M  M  +  M  M  M  M  +  M  +|  21        |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
      Hemorrhage                           |    2                                                                 2   |      2  2.0|
      Hyperplasia, Lymphoid                |                                                                      2   |      1  2.0|
                                            __________________________________________________________________________|____________|
   Lymph Node, Mediastinal                 | M  +  M  +  M  M  M  M  +  M  +  +  M  +  +  +  +  +  +  M  +  M  +  M  M|  28        |
      Hyperplasia, Lymphoid                |                                                                          |      1  3.0|
      Infiltration Cellular, Plasma Cell   |                                  3                                       |      1  3.0|
                                            __________________________________________________________________________|____________|
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hematopoietic Cell Proliferation     |    3           3           3                                      3      |      6  3.0|
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  42                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 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|            |
 __________________________________________________________________________________________________________________________________ 
 HEMATOPOIETIC SYSTEM - cont               |                                                                          |            |
                                           |                                                                          |            |
      Hyperplasia, Lymphoid                |             2                                            3               |      4  2.5|
                                            __________________________________________________________________________|____________|
   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        |
      Inflammation, Chronic                |                                                                          |      1  3.0|
      Inflammation, Suppurative            |             3                                                            |      1  3.0|
      Ulcer                                |                                  2                                       |      1  2.0|
      Prepuce, Inflammation, Chronic       |                                                                          |      1  3.0|
      Prepuce, Ulcer                       |                                                                          |      1  3.0|
 _____________________________________________________________________________________________________________________|            |
 MUSCULOSKELETAL SYSTEM                    |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 NERVOUS SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 RESPIRATORY SYSTEM                        |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Larynx                                  | +  +  +  +  +  +  +  I  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Metaplasia, Squamous                 |    1  1  1  1  1  1     1  1     1  1  1     1     1  1  1  1  1  1      |     37  1.0|
                                            __________________________________________________________________________|____________|
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Infiltration Cellular, Diffuse,      |                                                                          |            |
          Histiocyte                       |                                                                3         |      2  3.0|
      Infiltration Cellular, Focal,        |                                                                          |            |
          Histiocyte                       |                                        3                                 |      5  2.6|
      Inflammation, Chronic                |                                                                2         |      1  2.0|
      Alveolar Epithelium, Hyperplasia     |                         3                                                |      4  2.3|
      Alveolar Epithelium, Goblet Cell,    |                                                                          |            |
           Metaplasia, Focal               |                                                                   3      |      1  3.0|
      Bronchus, Vacuolization Cytoplasmic  |          1           1                 1  1     1     1     1        1   |     18  1.0|
                                            __________________________________________________________________________|____________|
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Inflammation, Suppurative            |                                                                          |      1  3.0|
                                            __________________________________________________________________________|____________|
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 SPECIAL SENSES SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Ear                                     |                                                                          |   1        |
                                            __________________________________________________________________________|____________|
   Harderian Gland                         |             +                                               +            |   4        |
      Inflammation, Acute                  |                                                                          |      1  1.0|
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  43                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 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|            |
 __________________________________________________________________________________________________________________________________ 
 SPECIAL SENSES SYSTEM - cont              |                                                                          |            |
                                           |                                                                          |            |
 _____________________________________________________________________________________________________________________|            |
 URINARY SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Cyst                                 | 2                                                                        |      1  2.0|
      Infiltration Cellular, Mixed Cell    |                            2                                             |      1  2.0|
      Nephropathy                          |          1        2     1           2                 2     3  1         |     13  2.1|
      Glomerulus, Amyloid Deposition       |                                              2                           |      1  2.0|
                                            __________________________________________________________________________|____________|
   Urinary Bladder                         | +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  44                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 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  +  +|             
      Degeneration, Hyaline                |                                                                          |             
      Infiltration Cellular, Lymphocyte    |                                                                          |             
                                            __________________________________________________________________________|             
   Intestine Large, Colon                  | +  +  +  +  +  A  +  +  +  +  +  +  A  +  +  A  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Rectum                 | +  +  +  +  +  A  +  +  +  +  +  +  A  +  +  A  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Cecum                  | +  +  +  +  +  A  +  +  +  +  +  +  A  +  +  A  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Duodenum               | +  +  +  +  +  A  +  +  +  +  +  +  A  +  +  A  +  +  +  +  +  +  +  +  +|             
      Hyperplasia, Lymphoid                |                      3                                                   |             
      Inflammation, Chronic                |       2                                                                  |             
      Necrosis, Focal                      |                                                                   2      |             
                                            __________________________________________________________________________|             
   Intestine Small, Jejunum                | +  +  +  +  +  A  +  +  +  +  +  +  A  +  +  A  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Ileum                  | +  +  +  +  +  A  +  +  +  +  +  +  A  +  +  A  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Clear Cell Focus                     |                                                                          |             
      Clear Cell Focus, Multiple           |                                                                          |             
      Eosinophilic Focus                   |             X                    X        X              X     X     X   |             
      Eosinophilic Focus, Multiple         |    X                                                                     |             
      Inflammation, Chronic                | 1  1     2  2     1  2  1     2     2  2  2  2     2  2  2  1  2  1  2  1|             
      Karyomegaly                          | 1  3        3     3  2  3     3     3     3  3     3  3  3  3  3  3  3  2|             
      Necrosis, Focal                      |                      3                 2     3                           |             
      Regeneration                         | 2  2        3        2  3     3     2     2  2  3  3  3  3  2  1  2  3   |             
      Vacuolization Cytoplasmic, Diffuse   | 2                                                                        |             
      Vacuolization Cytoplasmic, Focal     |                                                          1               |             
      Bile Duct, Hyperplasia               |                                                    2                     |             
      Oval Cell, Hyperplasia               | 1  3        3     3  3  3     3     3  1  3  2     3  3  3  3  3  3  3  1|             
                                            __________________________________________________________________________|             
   Mesentery                               | +        +                                                               |             
      Mineralization                       |                                                                          |             
      Fat, Necrosis                        |          3                                                               |             
                                            __________________________________________________________________________|             
   Pancreas                                | +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Cyst                                 |                                                                          |             
                                            __________________________________________________________________________|             
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 CARDIOVASCULAR SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Blood Vessel                            |                            +                                             |             
                                            __________________________________________________________________________|             
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Cardiomyopathy                       | 1                                                                        |             
      Inflammation, Chronic                |                         2                                                |             
      Artery, Inflammation, Chronic        |                                                                          |             
      Atrium, Thrombosis                   |                                                                      3   |             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM                          |                                                                          |             
                                           |                                                                          |             
 _____________________________________________________________________________________________________________________|             
                                                             Page  45                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 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|             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM - cont                   |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +|             
      Accessory Adrenal Cortical Nodule    |    1                                                                     |             
      Hyperplasia                          | 2        1                                1                              |             
      Necrosis, Diffuse                    |                                              4                           |             
                                            __________________________________________________________________________|             
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +|             
      Necrosis, Diffuse                    |                                              4                           |             
                                            __________________________________________________________________________|             
   Islets, Pancreatic                      | +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Parathyroid Gland                       | M  +  M  +  +  +  M  M  M  M  +  +  +  +  +  M  +  +  M  +  M  M  +  M  +|             
                                            __________________________________________________________________________|             
   Pituitary Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Follicular Cell, Hyperplasia         |             4              1                       1  1           1      |             
 _____________________________________________________________________________________________________________________|             
 GENERAL BODY SYSTEM                       |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Tissue NOS                              |                                              +                           |             
      Inflammation, Chronic                |                                              2                           |             
 _____________________________________________________________________________________________________________________|             
 GENITAL SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Epididymis                              | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Inflammation, Chronic                |          2                                                               |             
      Mineralization                       |                                                                          |             
                                            __________________________________________________________________________|             
   Preputial Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Cyst                                 |       3        3                                      3                  |             
      Inflammation, Chronic                |             2     1                                               1      |             
      Inflammation, Suppurative            |                                                 4                        |             
                                            __________________________________________________________________________|             
   Prostate                                | +  +  +  +  M  +  +  +  +  +  +  +  A  +  +  +  M  +  +  +  +  +  +  M  +|             
      Inflammation                         |                                                                          |             
                                            __________________________________________________________________________|             
   Seminal Vesicle                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +|             
      Inflammation, Chronic                |          2                                                               |             
                                            __________________________________________________________________________|             
   Testes                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Degeneration, Focal                  |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Lymph Node                              |                                                                          |             
      Iliac, Infiltration Cellular,        |                                                                          |             
          Histiocyte                       |                                                                          |             
                                            __________________________________________________________________________|             
   Lymph Node, Bronchial                   | M  +  M  M  +  A  +  M  +  M  M  M  +  +  +  M  +  +  M  +  +  +  +  M  M|             
                                            __________________________________________________________________________|             
   Lymph Node, Mandibular                  | M  M  M  M  +  +  M  M  M  +  +  +  M  +  +  M  +  M  +  +  +  +  M  +  +|             
                                            __________________________________________________________________________|             
   Lymph Node, Mesenteric                  | M  +  +  M  +  A  +  +  M  +  +  +  A  +  +  A  +  +  +  +  +  +  +  +  +|             
      Hematopoietic Cell Proliferation     |                                                                          |             
      Hemorrhage                           |    2                                                              3      |             
      Inflammation, Chronic                |                                                    2  1                  |             
                                            __________________________________________________________________________|             
   Lymph Node, Mediastinal                 | +  +  I  +  +  +  M  +  +  +  +  M  +  +  +  +  +  +  M  M  +  M  M  M  M|             
      Hyperplasia, Lymphoid                |                            3                                             |             
 _____________________________________________________________________________________________________________________|             
                                                             Page  46                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 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|             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM - cont               |                                                                          |             
                                           |                                                                          |             
      Infiltration Cellular, Histiocyte    |                      3                                                   |             
      Inflammation, Chronic                |                                                                          |             
                                            __________________________________________________________________________|             
   Spleen                                  | +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hematopoietic Cell Proliferation     |       3  3           3                                               3   |             
                                            __________________________________________________________________________|             
   Thymus                                  | 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                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Ulcer                                |                                                                          |             
      Epidermis, Hyperplasia               |                                                                          |             
      Prepuce, Ulcer                       |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM                    |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 NERVOUS SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 RESPIRATORY SYSTEM                        |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Larynx                                  | +  +  +  +  +  A  +  +  +  +  +  I  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Metaplasia, Squamous                 | 1  1  1  1  1     1  1  1  1  1     1  1  1  1  1  1  1  1  1  1  1  1  1|             
                                            __________________________________________________________________________|             
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hemorrhage                           |                                                                   2      |             
      Infiltration Cellular, Diffuse,      |                                                                          |             
          Histiocyte                       |       1           2     3                                                |             
      Infiltration Cellular, Focal,        |                                                                          |             
          Histiocyte                       |       3        3           4  4           2                              |             
      Inflammation, Chronic                |                                        3                                 |             
      Alveolar Epithelium, Hyperplasia     |                                                    1                     |             
      Artery, Thrombosis                   |                                                                          |             
      Bronchus, Hyperplasia                |                               3                                          |             
      Bronchus, Vacuolization Cytoplasmic  | 1  1  1  1  1     1  1     1  1  1                    1  1  1  1  1     1|             
                                            __________________________________________________________________________|             
   Nose                                    | +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Olfactory Epithelium, Atrophy        | 1  2  1              1     1  2  1  2     2  2           1     1  1  1   |             
      Olfactory Epithelium, Degeneration,  |                                                                          |             
           Hyaline                         |       2                                                        2         |             
                                            __________________________________________________________________________|             
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 SPECIAL SENSES SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Eye                                     | +                                                                        |             
      Cornea, Inflammation                 | 3                                                                        |             
                                            __________________________________________________________________________|             
   Harderian Gland                         | +                             +                 +  +                     |             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM                            |                                                                          |             
 _____________________________________________________________________________________________________________________|             
                                                             Page  47                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 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|             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM - cont                     |                                                                          |             
                                           |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Infiltration Cellular, Mixed Cell    |    2                                2                                3   |             
      Inflammation, Chronic                |                            1                                             |             
      Metaplasia, Osseous                  |                                                                          |             
      Nephropathy                          |                      1  1                          4  1              3   |             
                                            __________________________________________________________________________|             
   Ureter                                  |    +                                                                     |             
                                            __________________________________________________________________________|             
   Urinary Bladder                         | +  +  +  +  +  A  +  +  +  +  +  +  A  +  +  A  +  +  +  +  +  +  +  +  +|             
      Inflammation                         |                                                                          |             
 _____________________________________________________________________________________________________________________|             
                                                             Page  48                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 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        |
      Degeneration, Hyaline                |                      3  2                                                |      2  2.5|
      Infiltration Cellular, Lymphocyte    |                         2                                                |      1  2.0|
                                            __________________________________________________________________________|____________|
   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        |
      Hyperplasia, Lymphoid                |                                                                          |      1  3.0|
      Inflammation, Chronic                |                                                                          |      1  2.0|
      Necrosis, Focal                      |                                                                          |      1  2.0|
                                            __________________________________________________________________________|____________|
   Intestine Small, Jejunum                | +  +  +  +  A  +  +  +  +  +  +  A  +  +  A  +  A  +  +  A  +  +  +  +  +|  42        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Ileum                  | +  +  +  +  A  +  +  +  +  +  +  +  +  +  A  +  A  +  +  A  +  +  +  +  +|  43        |
                                            __________________________________________________________________________|____________|
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Clear Cell Focus                     |                      X                             X                     |      2     |
      Clear Cell Focus, Multiple           |                                                       X                  |      1     |
      Eosinophilic Focus                   |    X     X     X                                                         |      9     |
      Eosinophilic Focus, Multiple         |                                                                X        X|      3     |
      Inflammation, Chronic                |    1  2  2     2  2  2  2     2  1  2  2  2  1     2  1  1     2  2  2  3|     40  1.7|
      Karyomegaly                          |    3  3  3     3  3  3  3  2  3  2  3  3  2  2     3  2  2     3  3  3  3|     39  2.7|
      Necrosis, Focal                      |                                     2        2              2            |      6  2.3|
      Regeneration                         |    2  3  3     3  2  2  3        2  2  3  2  1     4  2        2  3  2  3|     35  2.4|
      Vacuolization Cytoplasmic, Diffuse   |                                                                          |      1  2.0|
      Vacuolization Cytoplasmic, Focal     |                                                                          |      1  1.0|
      Bile Duct, Hyperplasia               |    2     2              1           2                                   1|      6  1.7|
      Oval Cell, Hyperplasia               |    3  3  3     3  3  3  3  2  3  3  3  3  3  2     3  2  2     3  3  3  3|     40  2.7|
                                            __________________________________________________________________________|____________|
   Mesentery                               |                +                                   +                 +   |   5        |
      Mineralization                       |                                                    4                     |      1  4.0|
      Fat, Necrosis                        |                                                    4                 3   |      3  3.3|
                                            __________________________________________________________________________|____________|
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Cyst                                 |                                                       2                  |      1  2.0|
                                            __________________________________________________________________________|____________|
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 CARDIOVASCULAR SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Blood Vessel                            | +                                                        +               |   3        |
                                            __________________________________________________________________________|____________|
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Cardiomyopathy                       |    1                                                                     |      2  1.0|
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  49                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 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|            |
 __________________________________________________________________________________________________________________________________ 
 CARDIOVASCULAR SYSTEM - cont              |                                                                          |            |
                                           |                                                                          |            |
      Inflammation, Chronic                |                                                                          |      1  2.0|
      Artery, Inflammation, Chronic        |                2                                                         |      1  2.0|
      Atrium, Thrombosis                   |                                                          2     4         |      3  3.0|
 _____________________________________________________________________________________________________________________|            |
 ENDOCRINE SYSTEM                          |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Accessory Adrenal Cortical Nodule    |                                                                          |      1  1.0|
      Hyperplasia                          | 1                                                     1                  |      5  1.2|
      Necrosis, Diffuse                    |                                                                          |      1  4.0|
                                            __________________________________________________________________________|____________|
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Necrosis, Diffuse                    |                                                                          |      1  4.0|
                                            __________________________________________________________________________|____________|
   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, Hyperplasia         |    1           3  3              1                 1        1            |     11  1.6|
 _____________________________________________________________________________________________________________________|            |
 GENERAL BODY SYSTEM                       |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Tissue NOS                              |                                                                          |   1        |
      Inflammation, Chronic                |                                                                          |      1  2.0|
 _____________________________________________________________________________________________________________________|            |
 GENITAL SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Epididymis                              | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Inflammation, Chronic                |                                                                          |      1  2.0|
      Mineralization                       |                                     3                                    |      1  3.0|
                                            __________________________________________________________________________|____________|
   Preputial Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Cyst                                 |                                                                          |      3  3.0|
      Inflammation, Chronic                |          1                    1     2        1        1           3      |      9  1.4|
      Inflammation, Suppurative            |                   3                                                      |      2  3.5|
                                            __________________________________________________________________________|____________|
   Prostate                                | +  +  I  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  44        |
      Inflammation                         |                                     4                             2      |      2  3.0|
                                            __________________________________________________________________________|____________|
   Seminal Vesicle                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Inflammation, Chronic                |                                                                          |      1  2.0|
                                            __________________________________________________________________________|____________|
   Testes                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Degeneration, Focal                  |                                     2                                    |      1  2.0|
 _____________________________________________________________________________________________________________________|            |
 HEMATOPOIETIC SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Lymph Node                              |                            +        +                                    |   2        |
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  50                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 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|            |
 __________________________________________________________________________________________________________________________________ 
 HEMATOPOIETIC SYSTEM - cont               |                                                                          |            |
                                           |                                                                          |            |
      Iliac, Infiltration Cellular,        |                                                                          |            |
          Histiocyte                       |                                     3                                    |      1  3.0|
                                            __________________________________________________________________________|____________|
   Lymph Node, Bronchial                   | +  +  +  +  +  +  +  M  +  +  +  M  +  +  +  M  M  M  M  M  +  +  M  M  M|  28        |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mandibular                  | M  M  M  +  +  +  M  +  +  M  M  +  M  +  +  +  M  +  +  M  +  +  M  +  +|  29        |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +|  43        |
      Hematopoietic Cell Proliferation     |                                           2                              |      1  2.0|
      Hemorrhage                           |                                           3                    3         |      4  2.8|
      Inflammation, Chronic                |                                                                          |      2  1.5|
                                            __________________________________________________________________________|____________|
   Lymph Node, Mediastinal                 | +  M  +  M  M  M  +  M  M  +  +  +  +  +  +  M  +  +  +  M  M  +  +  +  M|  31        |
      Hyperplasia, Lymphoid                |                               3                 3                 2      |      4  2.8|
      Infiltration Cellular, Histiocyte    |                                                                          |      1  3.0|
      Inflammation, Chronic                |       3                                                                  |      1  3.0|
                                            __________________________________________________________________________|____________|
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Hematopoietic Cell Proliferation     |                                     3                             3      |      6  3.0|
                                            __________________________________________________________________________|____________|
   Thymus                                  | +  +  M  +  +  M  +  +  +  +  +  M  +  +  M  M  M  +  +  +  M  +  I  +  +|  33        |
 _____________________________________________________________________________________________________________________|            |
 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        |
      Ulcer                                |                2                                                  3      |      2  2.5|
      Epidermis, Hyperplasia               |                                     2                                    |      1  2.0|
      Prepuce, Ulcer                       |                2                                                         |      1  2.0|
 _____________________________________________________________________________________________________________________|            |
 MUSCULOSKELETAL SYSTEM                    |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 NERVOUS SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 RESPIRATORY SYSTEM                        |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
      Metaplasia, Squamous                 | 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|     48  1.0|
                                            __________________________________________________________________________|____________|
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hemorrhage                           |                                                                          |      1  2.0|
      Infiltration Cellular, Diffuse,      |                                                                          |            |
          Histiocyte                       |                                                                3         |      4  2.3|
      Infiltration Cellular, Focal,        |                                                                          |            |
          Histiocyte                       |                               3                                   3     2|      8  3.0|
      Inflammation, Chronic                |                                                                          |      1  3.0|
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  51                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 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                 |                                                                          |            |
                                           |                                                                          |            |
      Alveolar Epithelium, Hyperplasia     |                         1        4                 1                     |      4  1.8|
      Artery, Thrombosis                   |                                                          2               |      1  2.0|
      Bronchus, Hyperplasia                |                                                                          |      1  3.0|
      Bronchus, Vacuolization Cytoplasmic  | 1     1  1  1  1     1  1  1  1  1  1  1     1     1  1  1        1     1|     34  1.0|
                                            __________________________________________________________________________|____________|
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +|  48        |
      Olfactory Epithelium, Atrophy        | 1        1  1  1     1     1     2           1  1  1  1  2     1     1  1|     29  1.2|
      Olfactory Epithelium, Degeneration,  |                                                                          |            |
           Hyaline                         |                                                                          |      2  2.0|
                                            __________________________________________________________________________|____________|
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 SPECIAL SENSES SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Eye                                     |                                                                          |   1        |
      Cornea, Inflammation                 |                                                                          |      1  3.0|
                                            __________________________________________________________________________|____________|
   Harderian Gland                         |                                                                          |   4        |
 _____________________________________________________________________________________________________________________|            |
 URINARY SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Infiltration Cellular, Mixed Cell    |       2        2                                                         |      5  2.2|
      Inflammation, Chronic                |                                                                          |      1  1.0|
      Metaplasia, Osseous                  |                   2                                                      |      1  2.0|
      Nephropathy                          |                                                             2  1         |      7  1.9|
                                            __________________________________________________________________________|____________|
   Ureter                                  |                                                                          |   1        |
                                            __________________________________________________________________________|____________|
   Urinary Bladder                         | +  +  I  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +|  45        |
      Inflammation                         |                   3                 3                             3      |      3  3.0|
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  52                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 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                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Cyst                                 |                                                                          |             
      Eosinophilic Focus                   |                                                                          |             
      Inflammation, Chronic                | 1     2  1  1        3  2  2  1  2     3     2  1  1  1  1  1  1  1  1   |             
      Karyomegaly                          | 3  2  3  3  3  1  1  3  2  3  3  3  2  3     3  2  3  3  3  3  3  2  3   |             
      Mitotic Alteration                   |    3                                                                     |             
      Necrosis, Focal                      |                                                                          |             
      Regeneration                         | 2  3  3  2           3  3  3  2  3  3  3     1  3  2  3  3  3  3  2  3   |             
      Bile Duct, Hyperplasia               |                                              1              3            |             
      Oval Cell, Hyperplasia               | 3  2  3  3  3     1  3  3  3  3  3  2  3     3  2  3  3  2  3  3  3  3  1|             
                                            __________________________________________________________________________|             
   Mesentery                               |       +              +              +        +                           |             
      Inflammation, Chronic                |       2                                                                  |             
      Artery, Fibrosis                     |                                     3                                    |             
                                            __________________________________________________________________________|             
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hyperplasia, Squamous                |                      4                                                   |             
      Inflammation                         |                                                                          |             
                                            __________________________________________________________________________|             
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Mineralization                       |                                                                          |             
                                            __________________________________________________________________________|             
   Tooth                                   |                                           +                              |             
      Inflammation                         |                                           3                              |             
 _____________________________________________________________________________________________________________________|             
 CARDIOVASCULAR SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Cardiomyopathy                       |                                                                          |             
      Atrium, Thrombosis                   |                                                       4        2         |             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM                          |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hyperplasia                          |                      2                                                   |             
                                            __________________________________________________________________________|             
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hyperplasia                          | 1                                                  1                 3   |             
                                            __________________________________________________________________________|             
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Parathyroid Gland                       | +  +  +  +  M  M  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  M  M  +|             
                                            __________________________________________________________________________|             
   Pituitary Gland                         | +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
                                                             Page  53                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 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|             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM - cont                   |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Inflammation                         |                                                                          |             
      Follicular Cell, Hyperplasia         |       2                 1                       1                    2   |             
 _____________________________________________________________________________________________________________________|             
 GENERAL BODY SYSTEM                       |                                                                          |             
                                           |                                                                          |             
    None                                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 GENITAL SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Epididymis                              | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Degeneration                         |                                                                          |             
      Inflammation, Chronic                |                                                       2                  |             
                                            __________________________________________________________________________|             
   Preputial Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Cyst                                 |                                                       2                  |             
      Inflammation, Chronic                |                   1                                      1               |             
                                            __________________________________________________________________________|             
   Prostate                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Inflammation                         |                   1                                                      |             
                                            __________________________________________________________________________|             
   Seminal Vesicle                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Testes                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Atrophy                              |                         2                                                |             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Lymph Node                              |                                        +     +                           |             
      Iliac, Hyperplasia, Lymphoid         |                                        3                                 |             
                                            __________________________________________________________________________|             
   Lymph Node, Bronchial                   | M  +  +  +  M  +  +  +  +  M  +  +  M  M  M  +  M  M  +  M  +  +  M  I  +|             
      Infiltration Cellular, Histiocyte    |                                                                          |             
                                            __________________________________________________________________________|             
   Lymph Node, Mandibular                  | +  +  +  +  +  M  M  +  M  M  +  M  M  A  +  +  +  +  M  +  M  +  M  +  +|             
                                            __________________________________________________________________________|             
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hemorrhage                           |                         3                                                |             
      Hyperplasia, Lymphoid                |                                        3                                 |             
      Inflammation, Chronic                |                      2                                2                  |             
                                            __________________________________________________________________________|             
   Lymph Node, Mediastinal                 | +  +  +  I  +  M  M  +  +  M  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +|             
      Inflammation, Chronic                |                                                                         1|             
                                            __________________________________________________________________________|             
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Angiectasis                          |                                                                          |             
      Hematopoietic Cell Proliferation     |                   2  2              3  3           3           3         |             
      Hyperplasia, Lymphoid                |       3                                                                  |             
                                            __________________________________________________________________________|             
   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  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Inflammation, Chronic                |                   2              2                                       |             
      Epidermis, Hyperplasia               |                                                                          |             
 _____________________________________________________________________________________________________________________|             
                                                             Page  54                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 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|             
 _____________________________________________________________________________________________________________________|             
 INTEGUMENTARY SYSTEM - cont               |                                                                          |             
                                           |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM                    |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Fracture                             |                                                                          |             
                                            __________________________________________________________________________|             
   Skeletal Muscle                         |                                                             +            |             
      Inflammation, Chronic, Focal         |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 NERVOUS SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Spinal Cord                             |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 RESPIRATORY SYSTEM                        |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  I  +  +|             
      Metaplasia, Squamous                 | 1  1  1  1  1  1  1  1  1  1  1  1     1  1  1  1  1  1  2  1  1     1  1|             
                                            __________________________________________________________________________|             
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hemorrhage                           |                                                                   1      |             
      Infiltration Cellular, Diffuse,      |                                                                          |             
          Histiocyte                       | 2  1  2  2  1        1           1        1           3                  |             
      Infiltration Cellular, Focal,        |                                                                          |             
          Histiocyte                       | 3           4     3     2     4        2  3  1  3        2  4  2         |             
      Inflammation, Chronic                |          3                    3                 2                        |             
      Alveolar Epithelium, Hyperplasia     |                                  3                 2                     |             
      Bronchus, Vacuolization Cytoplasmic  | 1              1  1        1     1  1  1        1  1     1     1  1  1  1|             
                                            __________________________________________________________________________|             
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hemorrhage                           |                                                                          |             
      Inflammation, Suppurative            |                      2                                                  2|             
      Olfactory Epithelium, Atrophy        | 2  2     2  2  1  2  1  1  2  1  2     1  2  2  2  1  2  2  3  2  1  3  3|             
      Olfactory Epithelium, Degeneration,  |                                                                          |             
           Hyaline                         |                                                                          |             
      Olfactory Epithelium, Hyperplasia    |                   1           1           1  1                           |             
      Olfactory Epithelium, Metaplasia     |                                                                          |             
      Respiratory Epithelium, Degeneration,|                                                                          |             
           Hyaline                         |                                              1                           |             
                                            __________________________________________________________________________|             
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 SPECIAL SENSES SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Eye                                     |                                                                          |             
      Degeneration                         |                                                                          |             
      Hemorrhage                           |                                                                          |             
      Inflammation                         |                                                                          |             
                                            __________________________________________________________________________|             
   Harderian Gland                         |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
                                                             Page  55                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 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|             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM - cont                     |                                                                          |             
                                           |                                                                          |             
      Cyst                                 |                                                                          |             
      Infiltration Cellular, Mixed Cell    |                   2                    2                                 |             
      Mineralization                       |                                                                          |             
      Nephropathy                          |                                              3     2  2        3  1      |             
      Glomerulus, Amyloid Deposition       |                                                    2  2                  |             
      Medulla, Inflammation, Chronic       |                                                                          |             
      Renal Tubule, Hyperplasia            |                                                                          |             
                                            __________________________________________________________________________|             
   Ureter                                  |                               +                                          |             
                                            __________________________________________________________________________|             
   Urinary Bladder                         | +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +|             
      Inflammation                         |                   4                                   3                  |             
 _____________________________________________________________________________________________________________________|             
                                                             Page  56                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 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        |
      Cyst                                 |                                                                         2|      1  2.0|
      Eosinophilic Focus                   |                                  X  X                                    |      2     |
      Inflammation, Chronic                | 1  1  1  1  1     1  1  2  1        1  1  1  1  1  2  2     1     1  1  1|     39  1.3|
      Karyomegaly                          | 3  3  3  3  3  2  3  3  3  3        3  3  3  3  3  3  3     2     3  3   |     43  2.7|
      Mitotic Alteration                   |                                                                          |      1  3.0|
      Necrosis, Focal                      |                                                                         2|      1  2.0|
      Regeneration                         | 3  3  3  3  3     2     2  3        3  3  3  3  3  3  4     3     3  2   |     38  2.8|
      Bile Duct, Hyperplasia               |                         4           2                                    |      4  2.5|
      Oval Cell, Hyperplasia               | 3  3  3  3  3  1  3  3  4  2        3  3  3  3  3  3  3     3  1  3  3   |     44  2.7|
                                            __________________________________________________________________________|____________|
   Mesentery                               |                                                                          |   4        |
      Inflammation, Chronic                |                                                                          |      1  2.0|
      Artery, Fibrosis                     |                                                                          |      1  3.0|
                                            __________________________________________________________________________|____________|
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hyperplasia, Squamous                |          2                                                               |      2  3.0|
      Inflammation                         |          1                                                               |      1  1.0|
                                            __________________________________________________________________________|____________|
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Mineralization                       |             2                                                            |      1  2.0|
                                            __________________________________________________________________________|____________|
   Tooth                                   |                                                                          |   1        |
      Inflammation                         |                                                                          |      1  3.0|
 _____________________________________________________________________________________________________________________|            |
 CARDIOVASCULAR SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Cardiomyopathy                       |    1                                                                     |      1  1.0|
      Atrium, Thrombosis                   |                                                                          |      2  3.0|
 _____________________________________________________________________________________________________________________|            |
 ENDOCRINE SYSTEM                          |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hyperplasia                          |                                           1                              |      2  1.5|
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  57                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 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                   |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hyperplasia                          |    3     2                                                               |      5  2.0|
                                            __________________________________________________________________________|____________|
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   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        |
      Inflammation                         |                                  1                                       |      1  1.0|
      Follicular Cell, Hyperplasia         |             1           1                       2           1        2  1|     10  1.4|
 _____________________________________________________________________________________________________________________|            |
 GENERAL BODY SYSTEM                       |                                                                          |            |
                                           |                                                                          |            |
    None                                   |                                                                          |            |
 _____________________________________________________________________________________________________________________|            |
 GENITAL SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Epididymis                              | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Degeneration                         |                                                                   3      |      1  3.0|
      Inflammation, Chronic                |          2                                                               |      2  2.0|
                                            __________________________________________________________________________|____________|
   Preputial Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +|  49        |
      Cyst                                 |                                                                          |      1  2.0|
      Inflammation, Chronic                |          1     3                                                  1      |      5  1.4|
                                            __________________________________________________________________________|____________|
   Prostate                                | +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Inflammation                         |                                                                          |      1  1.0|
                                            __________________________________________________________________________|____________|
   Seminal Vesicle                         | +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Testes                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Atrophy                              |                                                                   2      |      2  2.0|
 _____________________________________________________________________________________________________________________|            |
 HEMATOPOIETIC SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Lymph Node                              |                                                                          |   2        |
      Iliac, Hyperplasia, Lymphoid         |                                                                          |      1  3.0|
                                            __________________________________________________________________________|____________|
   Lymph Node, Bronchial                   | M  M  +  +  M  M  M  M  M  +  +  +  +  M  M  M  +  M  M  +  +  M  M  +  +|  25        |
      Infiltration Cellular, Histiocyte    |                                                                         3|      1  3.0|
                                            __________________________________________________________________________|____________|
   Lymph Node, Mandibular                  | +  M  +  +  M  +  +  M  +  M  +  I  +  +  +  M  M  +  +  +  M  +  M  +  +|  31        |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  M  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  47        |
      Hemorrhage                           |                            3                                      3      |      3  3.0|
      Hyperplasia, Lymphoid                |                   3                                                      |      2  3.0|
      Inflammation, Chronic                |                                                                          |      2  2.0|
                                            __________________________________________________________________________|____________|
   Lymph Node, Mediastinal                 | +  +  +  +  M  +  +  +  I  M  +  +  M  +  M  M  M  +  M  +  +  +  +  M  M|  35        |
      Inflammation, Chronic                |                                                                          |      1  1.0|
                                            __________________________________________________________________________|____________|
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  58                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 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|            |
 __________________________________________________________________________________________________________________________________ 
 HEMATOPOIETIC SYSTEM - cont               |                                                                          |            |
                                           |                                                                          |            |
      Angiectasis                          | 2                                                                        |      1  2.0|
      Hematopoietic Cell Proliferation     | 3        3     3  3                    3     3              3     3      |     14  2.9|
      Hyperplasia, Lymphoid                |                                                                          |      1  3.0|
                                            __________________________________________________________________________|____________|
   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        |
      Inflammation, Chronic                |                                                                          |      2  2.0|
      Epidermis, Hyperplasia               |                                                          1               |      1  1.0|
 _____________________________________________________________________________________________________________________|            |
 MUSCULOSKELETAL SYSTEM                    |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Fracture                             |                                     X                                    |      1     |
                                            __________________________________________________________________________|____________|
   Skeletal Muscle                         |                                                          +               |   2        |
      Inflammation, Chronic, Focal         |                                                          2               |      1  2.0|
 _____________________________________________________________________________________________________________________|            |
 NERVOUS SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Spinal Cord                             |                   +                                                      |   1        |
 _____________________________________________________________________________________________________________________|            |
 RESPIRATORY SYSTEM                        |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Metaplasia, Squamous                 | 1  1  1  1  1  1  1  1        1  1  1  1  1  1     1  1  1  1  1  1  1   |     44  1.0|
                                            __________________________________________________________________________|____________|
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hemorrhage                           |                                                                          |      1  1.0|
      Infiltration Cellular, Diffuse,      |                                                                          |            |
          Histiocyte                       |                            1                                             |     10  1.5|
      Infiltration Cellular, Focal,        |                                                                          |            |
          Histiocyte                       |          1  3        4              3                                   2|     17  2.7|
      Inflammation, Chronic                |                                                                          |      3  2.7|
      Alveolar Epithelium, Hyperplasia     |          2                 2                                             |      4  2.3|
      Bronchus, Vacuolization Cytoplasmic  | 1  1  1  1  1  1  1     1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1|     38  1.0|
                                            __________________________________________________________________________|____________|
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Hemorrhage                           |                                     4                                    |      1  4.0|
      Inflammation, Suppurative            |                                  1  3                          3        2|      6  2.2|
      Olfactory Epithelium, Atrophy        | 2  2  2  1  2  1  1  2  3  2  2  2  2  1  1  2  1  2  1  3  2  2  1  3  3|     48  1.8|
      Olfactory Epithelium, Degeneration,  |                                                                          |            |
           Hyaline                         |    1                    3                                                |      2  2.0|
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  59                                                               
NTP Experiment-Test: 05156-06                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/03/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:24:25  
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 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|            |
 __________________________________________________________________________________________________________________________________ 
 RESPIRATORY SYSTEM - cont                 |                                                                          |            |
                                           |                                                                          |            |
      Olfactory Epithelium, Hyperplasia    |       1              1  1     1  1                             1         |     10  1.0|
      Olfactory Epithelium, Metaplasia     |                                                                      2  3|      2  2.5|
      Respiratory Epithelium, Degeneration,|                                                                          |            |
           Hyaline                         |                                                                          |      1  1.0|
                                            __________________________________________________________________________|____________|
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 SPECIAL SENSES SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Eye                                     |                                                                +         |   1        |
      Degeneration                         |                                                                4         |      1  4.0|
      Hemorrhage                           |                                                                4         |      1  4.0|
      Inflammation                         |                                                                4         |      1  4.0|
                                            __________________________________________________________________________|____________|
   Harderian Gland                         |                      +  +                             +     +  +        +|   6        |
 _____________________________________________________________________________________________________________________|            |
 URINARY SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Cyst                                 |                                           3                              |      1  3.0|
      Infiltration Cellular, Mixed Cell    |          1                                                               |      3  1.7|
      Mineralization                       |                                                 1                        |      1  1.0|
      Nephropathy                          |    2                          2                             2     2      |      9  2.1|
      Glomerulus, Amyloid Deposition       |                                                                          |      2  2.0|
      Medulla, Inflammation, Chronic       |                4                                                         |      1  4.0|
      Renal Tubule, Hyperplasia            |                   1                                                      |      1  1.0|
                                            __________________________________________________________________________|____________|
   Ureter                                  |                                                                          |   1        |
                                            __________________________________________________________________________|____________|
   Urinary Bladder                         | +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
      Inflammation                         | 3                                                                        |      3  3.3|
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  60                                                               
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                             ----------              END OF REPORT             ----------                                           
                             ------------------------------------------------------------