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TDMS Study 05156-05 Pathology Tables

NTP Experiment-Test: 05156-05  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/25/96
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:24:18

                                                           CORE STUDY




       Facility:  Battelle Northwest

       Chemical CAS #:  10026-24-1

       Lock Date:  07/15/94

       Cage Range:  All

       Reasons For Removal:    All

       Removal Date Range:     All

       Treatment Groups:       Include All


































a  Number of animals examined microscopically at site and number of animals with lesion

                                                              Page   1

NTP Experiment-Test: 05156-05  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/25/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:24:18  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS FEMALE                   CONTROL      0.3          1.0          3.0                                       
                                                                MG/M3        MG/M3        MG/M3                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially in Study                          50           50           50           50                                     
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                19           20           20           17                                     
    Natural Death                                      3            4            4            3                                     
  Survivors                                                                                                                         
    Terminal Sacrifice                                28           25           26           30                                     
  Other                                                             1                                                               
  Animals Examined Microscopically                    50           49           50           50                                     
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Intestine Large, Colon                             (48)         (45)         (48)         (48)                                   
   Intestine Large, Cecum                             (48)         (45)         (47)         (47)                                   
   Intestine Small, Duodenum                          (49)         (46)         (48)         (48)                                   
   Intestine Small, Ileum                             (49)         (45)         (47)         (47)                                   
   Liver                                              (50)         (49)         (50)         (49)                                   
      Hemangiosarcoma                                                            1 (2%)                                             
      Histiocytic Sarcoma                                                        1 (2%)                                             
      Pheochromocytoma Malignant, Metastatic,                                                                                       
          Adrenal Medulla                                                        1 (2%)                                             
   Mesentery                                          (5)          (8)          (6)          (13)                                   
      Sarcoma Stromal, Metastatic, Uterus                           1 (13%)                                                         
   Oral Mucosa                                        (1)          (2)                                                              
      Pharyngeal, Squamous Cell Papilloma              1 (100%)     2 (100%)                                                        
   Pancreas                                           (49)         (49)         (50)         (48)                                   
   Salivary Glands                                    (50)         (49)         (50)         (50)                                   
      Adenoma                                                                                 1 (2%)                                
      Sarcoma, Metastatic, Eye                                                                1 (2%)                                
   Stomach, Forestomach                               (50)         (49)         (50)         (50)                                   
      Leiomyoma                                                                               1 (2%)                                
   Stomach, Glandular                                 (49)         (49)         (49)         (48)                                   
      Carcinoid Tumor Benign                                        1 (2%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Heart                                              (50)         (49)         (50)         (50)                                   
      Carcinoma, Metastatic, Lung                                                             1 (2%)                                
      Carcinoma, Metastatic, Thyroid Gland             1 (2%)                                                                       
      Schwannoma Benign                                1 (2%)       2 (4%)       2 (4%)       1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                             Page   2                                                               
NTP Experiment-Test: 05156-05  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/25/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:24:18  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS FEMALE                   CONTROL      0.3          1.0          3.0                                       
                                                                MG/M3        MG/M3        MG/M3                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (49)         (49)         (50)         (49)                                   
      Adenoma                                                       1 (2%)                    1 (2%)                                
      Carcinoma, Metastatic, Kidney                    1 (2%)                                                                       
   Adrenal Medulla                                    (48)         (49)         (50)         (48)                                   
      Pheochromocytoma Malignant                                                 1 (2%)       1 (2%)                                
      Pheochromocytoma Complex                                                                1 (2%)                                
      Pheochromocytoma Benign                          2 (4%)       1 (2%)       3 (6%)       7 (15%)                               
      Bilateral, Pheochromocytoma Benign                                                      1 (2%)                                
   Islets, Pancreatic                                 (49)         (49)         (50)         (48)                                   
      Adenoma                                          4 (8%)       1 (2%)                                                          
      Carcinoma                                        2 (4%)                    1 (2%)                                             
   Pituitary Gland                                    (50)         (49)         (50)         (49)                                   
      Pars Distalis, Adenoma                          40 (80%)     39 (80%)     38 (76%)     40 (82%)                               
   Thyroid Gland                                      (49)         (49)         (50)         (48)                                   
      C-Cell, Adenoma                                  6 (12%)      6 (12%)      7 (14%)      3 (6%)                                
      C-Cell, Carcinoma                                3 (6%)                    2 (4%)       3 (6%)                                
      Follicular Cell, Adenoma                                      1 (2%)                    1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Clitoral Gland                                     (50)         (48)         (48)         (49)                                   
      Adenoma                                          5 (10%)      7 (15%)      3 (6%)       3 (6%)                                
      Carcinoma                                        2 (4%)       3 (6%)       4 (8%)       3 (6%)                                
      Bilateral, Adenoma                                                         2 (4%)                                             
   Ovary                                              (50)         (49)         (50)         (49)                                   
      Granulosa Cell Tumor Benign                      1 (2%)                                                                       
      Bilateral, Granulosa-Theca Tumor Benign                       1 (2%)                                                          
   Uterus                                             (50)         (49)         (50)         (49)                                   
      Histiocytic Sarcoma                                                                     1 (2%)                                
      Leiomyoma                                                                               1 (2%)                                
      Polyp Stromal                                    8 (16%)      7 (14%)     10 (20%)      4 (8%)                                
      Polyp Stromal, Multiple                                                    1 (2%)                                             
      Sarcoma Stromal                                  1 (2%)       2 (4%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                             Page   3                                                               
NTP Experiment-Test: 05156-05  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/25/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:24:18  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS FEMALE                   CONTROL      0.3          1.0          3.0                                       
                                                                MG/M3        MG/M3        MG/M3                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (49)         (49)         (50)         (50)                                   
   Lymph Node                                         (2)          (3)          (3)          (2)                                    
   Lymph Node, Bronchial                              (30)         (30)         (37)         (37)                                   
   Lymph Node, Mandibular                             (44)         (40)         (47)         (45)                                   
      Sarcoma, Metastatic, Eye                                                                1 (2%)                                
      Sarcoma, Metastatic, Skin                                                               1 (2%)                                
   Lymph Node, Mesenteric                             (49)         (49)         (50)         (48)                                   
   Lymph Node, Mediastinal                            (43)         (38)         (43)         (45)                                   
   Spleen                                             (49)         (48)         (50)         (49)                                   
      Histiocytic Sarcoma                                                                     1 (2%)                                
   Thymus                                             (42)         (45)         (45)         (44)                                   
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (50)         (49)         (50)         (49)                                   
      Adenoma                                          2 (4%)                                                                       
      Carcinoma                                        2 (4%)       2 (4%)       5 (10%)      4 (8%)                                
      Carcinoma, Multiple                              1 (2%)                                 1 (2%)                                
      Fibroadenoma                                    18 (36%)     18 (37%)     13 (26%)     20 (41%)                               
      Fibroadenoma, Multiple                           4 (8%)       4 (8%)       7 (14%)      7 (14%)                               
   Skin                                               (50)         (49)         (50)         (50)                                   
      Basal Cell Adenoma                                                                      1 (2%)                                
      Squamous Cell Papilloma                          1 (2%)                                                                       
      Sebaceous Gland, Adenoma                                      1 (2%)                    1 (2%)                                
      Subcutaneous Tissue, Fibroma                                                            1 (2%)                                
      Subcutaneous Tissue, Fibrosarcoma                                          1 (2%)                                             
      Subcutaneous Tissue, Lipoma                      2 (4%)                                                                       
      Subcutaneous Tissue, Sarcoma                                                            1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (50)         (49)         (50)         (50)                                   
      Sarcoma, Metastatic, Eye                                                                1 (2%)                                
   Skeletal Muscle                                                              (1)          (1)                                    
      Carcinoma, Metastatic, Lung                                                             1 (100%)                              
      Rhabdomyosarcoma                                                           1 (100%)                                           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (50)         (49)         (50)         (50)                                   
      Astrocytoma Benign                                                                      1 (2%)                                
      Astrocytoma Malignant                                         1 (2%)                                                          
      Oligodendroglioma Benign                                                   1 (2%)                                             
                                                             Page   4                                                               
NTP Experiment-Test: 05156-05  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/25/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:24:18  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS FEMALE                   CONTROL      0.3          1.0          3.0                                       
                                                                MG/M3        MG/M3        MG/M3                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Lung                                               (50)         (49)         (50)         (50)                                   
      Alveolar/Bronchiolar Adenoma                                  1 (2%)       9 (18%)      7 (14%)                               
      Alveolar/Bronchiolar Adenoma, Multiple                                     1 (2%)       2 (4%)                                
      Alveolar/Bronchiolar Carcinoma                                2 (4%)       6 (12%)      6 (12%)                               
      Carcinoma, Metastatic, Mammary Gland             1 (2%)                                                                       
      Histiocytic Sarcoma                                                                     1 (2%)                                
      Pheochromocytoma Malignant, Metastatic,                                                                                       
          Adrenal Medulla                                                        1 (2%)                                             
      Sarcoma, Metastatic, Eye                                                                1 (2%)                                
      Sarcoma, Metastatic, Skin                                                               1 (2%)                                
      Sarcoma, Metastatic, Uncertain Primary Site                   1 (2%)                                                          
      Squamous Cell Carcinoma                                                    1 (2%)       1 (2%)                                
      Mediastinum, Alveolar/Bronchiolar Carcinoma,                                                                                  
           Metastatic, Lung                                                                   1 (2%)                                
   Nose                                               (50)         (49)         (50)         (50)                                   
   Pleura                                                          (1)                                                              
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                (1)          (5)          (3)          (3)                                    
      Sarcoma                                                                                 1 (33%)                               
   Zymbal's Gland                                                  (1)          (1)                                                 
      Carcinoma                                                     1 (100%)     1 (100%)                                           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (49)         (49)         (50)         (48)                                   
      Histiocytic Sarcoma                                                                     1 (2%)                                
      Lipoma                                           1 (2%)                                 1 (2%)                                
      Mesenchymal Tumor Benign                                      1 (2%)                                                          
      Bilateral, Renal Tubule, Carcinoma, Multiple     1 (2%)                                                                       
   Urinary Bladder                                    (49)         (49)         (50)         (47)                                   
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SYSTEMIC LESIONS                                                                                                                   
   Multiple Organs                                   *(50)        *(49)        *(50)        *(50)                                   
      Histiocytic Sarcoma                                                        1 (2%)       1 (2%)                                
      Leukemia Mononuclear                            15 (30%)     16 (33%)     19 (38%)     10 (20%)                               
      Lymphoma Malignant                                                                      1 (2%)                                
      Mesothelioma Malignant                                        1 (2%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
     *   Number of animals with any tissue examined microscopically                                                                 
                                                             Page   5                                                               
NTP Experiment-Test: 05156-05  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/25/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:24:18  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS FEMALE                   CONTROL      0.3          1.0          3.0                                       
                                                                MG/M3        MG/M3        MG/M3                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
TUMOR SUMMARY                                                                                                                       
                                                                                                                                    
   Total Animals with Primary Neoplasms (b)            48          47          50          46                                       
     Total Primary Neoplasms                          123         122         141         139                                       
                                                                                                                                    
   Total Animals with Benign Neoplasms                 45          44          47          44                                       
     Total Benign Neoplasms                            96          94          97         105                                       
                                                                                                                                    
   Total Animals with Malignant Neoplasms              25          23          32          27                                       
     Total Malignant Neoplasms                         27          28          44          34                                       
                                                                                                                                    
   Total Animals with Metastatic Neoplasms              3           3           1           3                                       
     Total Metastatic Neoplasm                          3           3           2           9                                       
                                                                                                                                    
   Total Animals with Malignant Neoplasms                           1                                                               
   Uncertain Primary Site                                                                                                           
                                                                                                                                    
   Total Animals with Neoplasms Uncertain-                                                                                          
   Benign or Malignant                                                                                                              
     Total Uncertain Neoplasms                                                                                                      
                                                                                                                                    
____________________________________________________________________________________________________________________________________
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Primary tumors: all tumors except metastatic tumors                                                                              
                                                             Page   6                                                               
NTP Experiment-Test: 05156-05  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/25/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:24:18  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS MALE                     CONTROL      0.3          1.0          3.0                                       
                                                                MG/M3        MG/M3        MG/M3                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially in Study                          50           50           50           50                                     
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                30           34           26           34                                     
    Natural Death                                      3            1            3            1                                     
  Survivors                                                                                                                         
    Terminal Sacrifice                                17           15           21           15                                     
  Animals Examined Microscopically                    50           50           50           50                                     
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Intestine Large, Colon                             (49)         (50)         (49)         (49)                                   
   Intestine Large, Cecum                             (48)         (49)         (48)         (49)                                   
   Intestine Small, Duodenum                          (50)         (50)         (48)         (49)                                   
   Intestine Small, Jejunum                           (49)         (49)         (47)         (49)                                   
   Intestine Small, Ileum                             (50)         (49)         (47)         (48)                                   
   Liver                                              (50)         (50)         (48)         (50)                                   
      Carcinoma, Metastatic, Seminal Vesicle                        1 (2%)                                                          
      Hepatocellular Carcinoma                                      1 (2%)                                                          
      Hepatocellular Adenoma                           1 (2%)                    1 (2%)       1 (2%)                                
      Sarcoma, Metastatic, Uncertain Primary Site                   1 (2%)                                                          
   Mesentery                                          (21)         (14)         (11)         (14)                                   
      Carcinoma, Metastatic, Seminal Vesicle                        1 (7%)                                                          
      Sarcoma, Metastatic, Uncertain Primary Site                   1 (7%)                                                          
      Fat, Lipoma                                                                1 (9%)                                             
   Pancreas                                           (50)         (50)         (48)         (50)                                   
      Adenoma                                                                    1 (2%)       1 (2%)                                
      Carcinoma                                                                  1 (2%)                                             
      Carcinoma, Metastatic, Seminal Vesicle                        1 (2%)                                                          
      Mixed Tumor Malignant                                                                   1 (2%)                                
      Sarcoma, Metastatic, Uncertain Primary Site                   1 (2%)                                                          
   Salivary Glands                                    (50)         (50)         (50)         (50)                                   
   Stomach, Forestomach                               (50)         (50)         (49)         (50)                                   
   Stomach, Glandular                                 (50)         (50)         (48)         (50)                                   
      Schwannoma Malignant                                                                    1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Heart                                              (50)         (50)         (50)         (50)                                   
      Carcinoma, Metastatic, Seminal Vesicle                        1 (2%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                             Page   7                                                               
NTP Experiment-Test: 05156-05  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/25/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:24:18  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS MALE                     CONTROL      0.3          1.0          3.0                                       
                                                                MG/M3        MG/M3        MG/M3                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (50)         (50)         (48)         (50)                                   
      Adenoma                                                                    1 (2%)       1 (2%)                                
      Carcinoma                                                     1 (2%)       1 (2%)                                             
   Adrenal Medulla                                    (50)         (50)         (49)         (50)                                   
      Pheochromocytoma Malignant                                    2 (4%)       2 (4%)       2 (4%)                                
      Pheochromocytoma Complex                         1 (2%)                    1 (2%)                                             
      Pheochromocytoma Benign                         13 (26%)     15 (30%)     17 (35%)     15 (30%)                               
      Bilateral, Pheochromocytoma Benign               1 (2%)       4 (8%)       6 (12%)      5 (10%)                               
   Islets, Pancreatic                                 (50)         (50)         (48)         (50)                                   
      Adenoma                                          1 (2%)       4 (8%)       5 (10%)      5 (10%)                               
      Adenoma, Multiple                                1 (2%)       1 (2%)                                                          
      Carcinoma                                        3 (6%)       4 (8%)       4 (8%)       7 (14%)                               
   Pituitary Gland                                    (49)         (49)         (50)         (49)                                   
      Pars Distalis, Adenoma                          43 (88%)     40 (82%)     42 (84%)     41 (84%)                               
   Thyroid Gland                                      (49)         (50)         (48)         (50)                                   
      Bilateral, C-Cell, Adenoma                                                              1 (2%)                                
      C-Cell, Adenoma                                  4 (8%)       2 (4%)       3 (6%)       3 (6%)                                
      C-Cell, Carcinoma                                3 (6%)       3 (6%)       4 (8%)       3 (6%)                                
      Follicular Cell, Adenoma                                      1 (2%)                    1 (2%)                                
      Follicular Cell, Carcinoma                       1 (2%)       2 (4%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   Peritoneum                                                      (2)          (1)          (1)                                    
      Sarcoma, Metastatic, Uncertain Primary Site                   1 (50%)                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Epididymis                                         (50)         (50)         (50)         (50)                                   
   Preputial Gland                                    (50)         (50)         (49)         (50)                                   
      Adenoma                                                                    1 (2%)       1 (2%)                                
      Carcinoma                                        2 (4%)       2 (4%)                    3 (6%)                                
      Bilateral, Adenoma                                                         1 (2%)                                             
      Bilateral, Carcinoma                             1 (2%)                                                                       
   Prostate                                           (50)         (50)         (49)         (50)                                   
      Adenoma                                          1 (2%)       2 (4%)       4 (8%)       1 (2%)                                
   Seminal Vesicle                                    (50)         (50)         (49)         (49)                                   
      Carcinoma                                                     1 (2%)                                                          
      Sarcoma, Metastatic, Uncertain Primary Site                   1 (2%)                                                          
   Testes                                             (50)         (50)         (50)         (50)                                   
      Bilateral, Interstitial Cell, Adenoma           26 (52%)     18 (36%)     26 (52%)     19 (38%)                               
      Interstitial Cell, Adenoma                       9 (18%)     13 (26%)      7 (14%)     10 (20%)                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                             Page   8                                                               
NTP Experiment-Test: 05156-05  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/25/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:24:18  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS MALE                     CONTROL      0.3          1.0          3.0                                       
                                                                MG/M3        MG/M3        MG/M3                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (50)         (50)         (48)         (50)                                   
   Lymph Node                                         (8)          (9)          (9)          (9)                                    
   Lymph Node, Bronchial                              (45)         (30)         (41)         (49)                                   
   Lymph Node, Mandibular                             (46)         (47)         (47)         (49)                                   
   Lymph Node, Mesenteric                             (50)         (50)         (48)         (50)                                   
   Lymph Node, Mediastinal                            (47)         (46)         (44)         (49)                                   
      Carcinoma, Metastatic, Seminal Vesicle                        1 (2%)                                                          
   Spleen                                             (50)         (50)         (49)         (50)                                   
      Carcinoma, Metastatic, Seminal Vesicle                        1 (2%)                                                          
      Fibroma                                          1 (2%)                                                                       
      Sarcoma, Metastatic, Uncertain Primary Site                   1 (2%)                                                          
   Thymus                                             (45)         (42)         (47)         (48)                                   
      Thymoma Benign                                                             1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (30)         (34)         (36)         (38)                                   
      Fibroadenoma                                     3 (10%)      1 (3%)       2 (6%)       3 (8%)                                
      Fibroadenoma, Multiple                                                                  1 (3%)                                
   Skin                                               (50)         (48)         (50)         (50)                                   
      Basal Cell Adenoma                               2 (4%)                                                                       
      Basal Cell Carcinoma                                                                    1 (2%)                                
      Keratoacanthoma                                  2 (4%)       5 (10%)                   2 (4%)                                
      Keratoacanthoma, Multiple                                                               1 (2%)                                
      Sarcoma, Metastatic, Uncertain Primary Site                   1 (2%)                                                          
      Squamous Cell Papilloma                                                                 1 (2%)                                
      Sebaceous Gland, Adenoma                         1 (2%)       1 (2%)                                                          
      Subcutaneous Tissue, Fibroma                                  1 (2%)       2 (4%)       2 (4%)                                
      Subcutaneous Tissue, Fibrosarcoma                             2 (4%)       1 (2%)       2 (4%)                                
      Subcutaneous Tissue, Lipoma                                   1 (2%)       1 (2%)       1 (2%)                                
      Subcutaneous Tissue, Sarcoma                                                            1 (2%)                                
      Subcutaneous Tissue, Schwannoma Malignant        1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (50)         (50)         (50)         (50)                                   
      Chordoma                                         1 (2%)       1 (2%)                                                          
      Osteosarcoma                                                  3 (6%)                                                          
   Skeletal Muscle                                                 (2)          (1)          (1)                                    
      Carcinoma, Metastatic, Seminal Vesicle                        1 (50%)                                                         
      Sarcoma                                                                                 1 (100%)                              
      Sarcoma, Metastatic, Uncertain Primary Site                   1 (50%)                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                             Page   9                                                               
NTP Experiment-Test: 05156-05  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/25/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:24:18  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS MALE                     CONTROL      0.3          1.0          3.0                                       
                                                                MG/M3        MG/M3        MG/M3                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (50)         (50)         (50)         (50)                                   
      Astrocytoma Malignant                            1 (2%)                    1 (2%)                                             
   Spinal Cord                                                                  (1)                                                 
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Larynx                                             (50)         (49)         (48)         (50)                                   
   Lung                                               (50)         (50)         (48)         (50)                                   
      Alveolar/Bronchiolar Adenoma                     1 (2%)       4 (8%)       1 (2%)       5 (10%)                               
      Alveolar/Bronchiolar Adenoma, Multiple                                                  1 (2%)                                
      Alveolar/Bronchiolar Carcinoma                                             3 (6%)       1 (2%)                                
      Carcinoma, Metastatic, Seminal Vesicle                        1 (2%)                                                          
      Chordoma, Metastatic, Bone                       1 (2%)                                                                       
      Osteosarcoma, Metastatic, Bone                                1 (2%)                                                          
      Sarcoma, Metastatic, Skeletal Muscle                                                    1 (2%)                                
   Nose                                               (50)         (50)         (49)         (50)                                   
      Nasopharyngeal Duct, Squamous Cell Carcinoma                                            1 (2%)                                
   Pleura                                             (1)                                                                           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Zymbal's Gland                                     (1)                                    (2)                                    
      Carcinoma                                        1 (100%)                               2 (100%)                              
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (50)         (50)         (48)         (50)                                   
      Sarcoma, Metastatic, Uncertain Primary Site                   1 (2%)                                                          
      Renal Tubule, Adenoma                            1 (2%)                    1 (2%)                                             
   Urinary Bladder                                    (50)         (50)         (48)         (50)                                   
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SYSTEMIC LESIONS                                                                                                                   
   Multiple Organs                                   *(50)        *(50)        *(50)        *(50)                                   
      Leukemia Mononuclear                            30 (60%)     32 (64%)     29 (58%)     28 (56%)                               
      Mesothelioma Malignant                           3 (6%)       2 (4%)       2 (4%)       2 (4%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
     *   Number of animals with any tissue examined microscopically                                                                 
                                                             Page  10                                                               
NTP Experiment-Test: 05156-05  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                    COBALT SULFATE HEPTAHYDRATE                                Date: 07/25/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:24:18  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS MALE                     CONTROL      0.3          1.0          3.0                                       
                                                                MG/M3        MG/M3        MG/M3                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
TUMOR SUMMARY                                                                                                                       
                                                                                                                                    
   Total Animals with Primary Neoplasms (b)            50          50          50          50                                       
     Total Primary Neoplasms                          159         169         173         178                                       
                                                                                                                                    
   Total Animals with Benign Neoplasms                 48          46          47          48                                       
     Total Benign Neoplasms                           111         113         124         122                                       
                                                                                                                                    
   Total Animals with Malignant Neoplasms              38          41          35          38                                       
     Total Malignant Neoplasms                         48          56          49          56                                       
                                                                                                                                    
   Total Animals with Metastatic Neoplasms              1           3                       1                                       
     Total Metastatic Neoplasm                          1          18                       1                                       
                                                                                                                                    
   Total Animals with Malignant Neoplasms                           1                                                               
   Uncertain Primary Site                                                                                                           
                                                                                                                                    
   Total Animals with Neoplasms Uncertain-                                                                                          
   Benign or Malignant                                                                                                              
     Total Uncertain Neoplasms                                                                                                      
                                                                                                                                    
____________________________________________________________________________________________________________________________________
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Primary tumors: all tumors except metastatic tumors                                                                              
                                                             Page  11                                                               
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