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https://ntp.niehs.nih.gov/go/1152

TDMS Study 05123-05 Pathology Tables


                                     INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)
                                                            NICKEL OXIDE


NTP Experiment-Test: 05123-05                                                                                     Report: PEIRPT03
Study Type: CHRONIC                                                                                               Date: 05/20/95
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 04:33:14




       Facility:  Lovelace Inhalation Toxicology Research Institute

       Chemical CAS #:  001313991

       Lock Date:  04/19/94

       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: 05123-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NICKEL OXIDE                                       Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 04:33:14  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS FEMALE                   0 MG/M3      0 MG/M3      0.62MGM3     0.62MGM3     1.25MGM3     1.25MGM3        
                                                                LUNGTX                     LUNGTX                    LUNGTX         
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially In Study                          58            7           58            7           58            7           
  Scheduled Sacrifice                                  5            7            5            7            5            7           
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                27                        24                        27                        
    Natural Death                                      5                         3                         6                        
  Survivors                                                                                                                         
    Terminal Sacrifice                                21                        26                        20                        
  Animals Examined Microscopically                    58            7           58            7           58            7           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Intestine Large, Colon                             (57)                      (58)                      (58)                      
      Inflammation, Chronic Active                     1 (2%)                                                                       
      Mineralization                                                                                       1 (2%)                   
      Parasite Metazoan                                                          2 (3%)                    1 (2%)                   
   Intestine Large, Rectum                            (57)                      (58)                      (57)                      
      Parasite Metazoan                                2 (4%)                                              2 (4%)                   
   Intestine Large, Cecum                             (57)                      (58)                      (58)                      
      Parasite Metazoan                                                                                    1 (2%)                   
   Liver                                              (58)         (1)          (58)                      (58)                      
      Angiectasis                                                                2 (3%)                    1 (2%)                   
      Basophilic Focus                                26 (45%)                  38 (66%)                  27 (47%)                  
      Clear Cell Focus                                                           1 (2%)                                             
      Congestion                                       2 (3%)                    1 (2%)                    3 (5%)                   
      Cyst                                             1 (2%)                                                                       
      Degeneration, Cystic                                                       1 (2%)                    2 (3%)                   
      Eosinophilic Focus                               2 (3%)                    3 (5%)                    3 (5%)                   
      Fatty Change                                    21 (36%)                  18 (31%)                  16 (28%)                  
      Fibrosis                                                                   1 (2%)                                             
      Granuloma                                        1 (2%)                                                                       
      Hemorrhage                                                                 1 (2%)                                             
      Hepatodiaphragmatic Nodule                       7 (12%)      1 (100%)     3 (5%)                    9 (16%)                  
      Mixed Cell Focus                                 1 (2%)                                                                       
      Pigmentation, Bile                               1 (2%)                    1 (2%)                                             
      Pigmentation, Hemosiderin                        1 (2%)                    1 (2%)                                             
      Thrombosis                                                                                           1 (2%)                   
      Bile Duct, Hyperplasia                           4 (7%)                    3 (5%)                    3 (5%)                   
      Hepatocyte, Hyperplasia                          4 (7%)                    6 (10%)                   3 (5%)                   
      Hepatocyte, Necrosis                             6 (10%)                   7 (12%)                   3 (5%)                   
      Portal Vein, Thrombosis                                                                              1 (2%)                   
   Pancreas                                           (57)                      (58)                      (58)                      
      Atrophy                                                                    2 (3%)                    1 (2%)                   
      Acinus, Atrophy                                  1 (2%)                                                                       
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    2                                                              
NTP Experiment-Test: 05123-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NICKEL OXIDE                                       Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 04:33:14  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS FEMALE                   0 MG/M3      0 MG/M3      0.62MGM3     0.62MGM3     1.25MGM3     1.25MGM3        
                                                                LUNGTX                     LUNGTX                    LUNGTX         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Artery, Mineralization                                                                               1 (2%)                   
   Stomach, Forestomach                               (57)                      (58)                      (58)                      
      Edema                                            1 (2%)                                                                       
      Hyperkeratosis                                   1 (2%)                    1 (2%)                    4 (7%)                   
      Inflammation, Chronic                            1 (2%)                                              1 (2%)                   
      Inflammation, Chronic Active                                                                         1 (2%)                   
      Mineralization                                                                                       1 (2%)                   
      Ulcer                                                                      3 (5%)                    2 (3%)                   
   Stomach, Glandular                                 (57)                      (58)                      (58)                      
      Erosion                                                                    1 (2%)                    1 (2%)                   
      Mineralization                                                                                       1 (2%)                   
      Ulcer                                                                      1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Blood Vessel                                       (3)                       (1)                       (2)                       
      Aorta, Mineralization                                                                                1 (50%)                  
      Aorta, Polyarteritis                                                       1 (100%)                                           
      Mesenteric Artery, Polyarteritis                                           1 (100%)                                           
      Mesenteric Artery, Thrombosis                                              1 (100%)                                           
      Vena Cava, Mineralization                                                                            1 (50%)                  
   Heart                                              (58)                      (58)                      (58)                      
      Atrium, Thrombosis                               1 (2%)                    1 (2%)                    1 (2%)                   
      Vein, Inflammation, Chronic Active               1 (2%)                                                                       
      Ventricle, Mineralization                                                                            1 (2%)                   
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (58)                      (58)                      (58)                      
      Angiectasis                                      1 (2%)                    3 (5%)                    3 (5%)                   
      Atrophy                                          1 (2%)                                                                       
      Congestion                                       1 (2%)                    2 (3%)                    2 (3%)                   
      Cyst                                             1 (2%)                                                                       
      Degeneration                                     2 (3%)                                                                       
      Degeneration, Fatty                              2 (3%)                    3 (5%)                    5 (9%)                   
      Edema                                                                                                1 (2%)                   
      Hemorrhage                                       1 (2%)                                              1 (2%)                   
      Hyperplasia                                                                1 (2%)                    1 (2%)                   
      Bilateral, Angiectasis                                                     1 (2%)                                             
   Adrenal Medulla                                    (56)                      (57)                      (57)                      
      Angiectasis                                      3 (5%)                    1 (2%)                                             
      Congestion                                                                 1 (2%)                                             
      Hyperplasia                                      9 (16%)                  12 (21%)                  15 (26%)                  
   Islets, Pancreatic                                 (57)                      (58)                      (58)                      
      Hyperplasia                                                                1 (2%)                                             
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    3                                                              
NTP Experiment-Test: 05123-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NICKEL OXIDE                                       Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 04:33:14  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS FEMALE                   0 MG/M3      0 MG/M3      0.62MGM3     0.62MGM3     1.25MGM3     1.25MGM3        
                                                                LUNGTX                     LUNGTX                    LUNGTX         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ENDOCRINE SYSTEM - CONT                                                                                                             
   Parathyroid Gland                                  (50)                      (51)                      (55)                      
      Cyst                                                                       1 (2%)                                             
      Hyperplasia                                                                                          1 (2%)                   
   Pituitary Gland                                    (57)                      (57)         (2)          (57)         (3)          
      Angiectasis                                      1 (2%)                    1 (2%)                                             
      Pars Distalis, Angiectasis                       7 (12%)                   6 (11%)                   6 (11%)                  
      Pars Distalis, Cyst                              8 (14%)                   8 (14%)                  11 (19%)                  
      Pars Distalis, Degeneration                                                1 (2%)                                             
      Pars Distalis, Hyperplasia                       9 (16%)                  11 (19%)                   7 (12%)                  
      Pars Distalis, Hyperplasia, Cystic               1 (2%)                                                                       
      Pars Distalis, Hyperplasia, Diffuse                                                     2 (100%)                  3 (100%)    
      Pars Intermedia, Angiectasis                                               1 (2%)                    1 (2%)                   
      Pars Intermedia, Cyst                                                      1 (2%)                                             
      Pars Intermedia, Hypertrophy                                               1 (2%)                                             
   Thyroid Gland                                      (57)                      (57)                      (58)                      
      C-Cell, Hyperplasia                                                                                  3 (5%)                   
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Clitoral Gland                                     (58)                      (58)                      (56)                      
      Atrophy                                          1 (2%)                                                                       
      Ectasia                                          5 (9%)                    3 (5%)                    5 (9%)                   
      Hyperplasia, Cystic                                                        1 (2%)                                             
      Inflammation, Chronic Active                                               1 (2%)                                             
      Inflammation, Suppurative                                                  1 (2%)                    1 (2%)                   
   Ovary                                              (58)                      (58)                      (58)         (2)          
      Cyst                                             6 (10%)                   7 (12%)                   8 (14%)      2 (100%)    
   Uterus                                             (58)                      (58)                      (57)                      
      Cyst                                                                                                 1 (2%)                   
      Dilatation                                                                 1 (2%)                                             
      Prolapse                                                                                             1 (2%)                   
      Endometrium, Hyperplasia, Cystic                 5 (9%)                    1 (2%)                    2 (4%)                   
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (57)                      (58)                      (58)                      
      Fibrosis                                         5 (9%)                    3 (5%)                    3 (5%)                   
      Hyperplasia                                     14 (25%)                  15 (26%)                  15 (26%)                  
      Necrosis                                                                   1 (2%)                                             
   Lymph Node                                         (14)                      (6)                       (9)                       
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    4                                                              
NTP Experiment-Test: 05123-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NICKEL OXIDE                                       Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 04:33:14  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS FEMALE                   0 MG/M3      0 MG/M3      0.62MGM3     0.62MGM3     1.25MGM3     1.25MGM3        
                                                                LUNGTX                     LUNGTX                    LUNGTX         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
HEMATOPOIETIC SYSTEM - CONT                                                                                                         
      Hyperplasia, Lymphoid                                                      1 (17%)                                            
      Pigmentation                                     1 (7%)                                                                       
      Iliac, Hyperplasia, Lymphoid                     1 (7%)                                                                       
      Pancreatic, Hyperplasia, Lymphoid                                                                    1 (11%)                  
      Pancreatic, Inflammation, Chronic Active         1 (7%)                                                                       
      Popliteal, Pigmentation                          1 (7%)                                                                       
      Renal, Congestion                                                          2 (33%)                                            
      Renal, Hyperplasia, Lymphoid                                                                         1 (11%)                  
      Renal, Pigmentation, Hemosiderin                 1 (7%)                                                                       
   Lymph Node, Bronchial                              (54)         (6)          (55)         (7)          (58)         (7)          
      Congestion                                       2 (4%)                    2 (4%)                    1 (2%)                   
      Edema                                                                      1 (2%)                    1 (2%)                   
      Hyperplasia, Lymphoid                            1 (2%)                    5 (9%)                   23 (40%)      4 (57%)     
      Hyperplasia, Macrophage                                                    1 (2%)                                             
      Pigmentation                                                              47 (85%)                  57 (98%)      7 (100%)    
      Pigmentation, Hemosiderin                        1 (2%)                                                                       
   Lymph Node, Mandibular                             (52)                      (50)                      (56)                      
      Congestion                                                                 1 (2%)                                             
      Hyperplasia, Lymphoid                            3 (6%)                    2 (4%)                    3 (5%)                   
      Pigmentation                                     2 (4%)                                                                       
   Lymph Node, Mesenteric                             (56)                      (58)                      (58)                      
      Congestion                                       1 (2%)                                                                       
      Inflammation, Chronic Active                     1 (2%)                                                                       
      Pigmentation                                     4 (7%)                    2 (3%)                                             
   Lymph Node, Mediastinal                            (53)         (6)          (51)         (7)          (52)         (6)          
      Congestion                                       1 (2%)                    5 (10%)                   7 (13%)                  
      Ectasia                                                                                              1 (2%)                   
      Edema                                                                                                1 (2%)                   
      Hyperplasia, Lymphoid                            1 (2%)                    9 (18%)                  14 (27%)                  
      Hyperplasia, Plasma Cell                         1 (2%)                                              1 (2%)                   
      Inflammation, Chronic Active                     1 (2%)                                                                       
      Pigmentation                                                              37 (73%)                  43 (83%)      2 (33%)     
      Pigmentation, Hemosiderin                                                                            1 (2%)                   
   Spleen                                             (58)                      (58)                      (58)                      
      Fibrosis                                         1 (2%)                    3 (5%)                    3 (5%)                   
      Hematopoietic Cell Proliferation                                           1 (2%)                                             
      Hemorrhage                                                                                           1 (2%)                   
      Hyperplasia, Lymphoid                                                                                1 (2%)                   
      Infarct                                          1 (2%)                    1 (2%)                                             
      Necrosis                                                                   1 (2%)                                             
      Capsule, Fibrosis                                                                                    1 (2%)                   
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    5                                                              
NTP Experiment-Test: 05123-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NICKEL OXIDE                                       Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 04:33:14  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS FEMALE                   0 MG/M3      0 MG/M3      0.62MGM3     0.62MGM3     1.25MGM3     1.25MGM3        
                                                                LUNGTX                     LUNGTX                    LUNGTX         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (58)                      (58)                      (58)                      
      Hyperplasia, Glandular                                                     1 (2%)                                             
   Skin                                               (4)                       (3)                       (3)                       
      Inflammation, Suppurative                                                  1 (33%)                                            
      Subcutaneous Tissue, Edema                                                 1 (33%)                                            
      Subcutaneous Tissue, Fibrosis                                                                        1 (33%)                  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (58)                      (58)                      (58)                      
      Hyperostosis                                                                                         2 (3%)                   
      Osteopetrosis                                    4 (7%)                    2 (3%)                                             
      Femur, Hyperostosis                              5 (9%)                    2 (3%)                   10 (17%)                  
   Skeletal Muscle                                    (1)                                                                           
      Inflammation, Chronic                            1 (100%)                                                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (58)                      (58)                      (58)                      
      Hemorrhage                                       1 (2%)                                                                       
      Cerebellum, Compression                                                    1 (2%)                    1 (2%)                   
      Cerebrum, Compression                            5 (9%)                    4 (7%)                    3 (5%)                   
      Cerebrum, Ventricle, Dilatation                                                                      2 (3%)                   
      Hypothalamus, Compression                        2 (3%)                    1 (2%)                    3 (5%)                   
      Pons, Compression                                                                                    1 (2%)                   
      Ventricle, Dilatation                            2 (3%)                    1 (2%)                    1 (2%)                   
      Ventricle, Ectasia                               1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Larynx                                             (58)                      (58)                      (58)                      
      Inflammation, Chronic                            4 (7%)                                              2 (3%)                   
      Inflammation, Chronic Active                     3 (5%)                    2 (3%)                    2 (3%)                   
      Inflammation, Suppurative                                                  1 (2%)                    2 (3%)                   
   Lung                                               (58)         (7)          (58)         (7)          (58)         (7)          
      Congestion                                       1 (2%)                                              1 (2%)                   
      Hemorrhage                                                                                           2 (3%)                   
      Inflammation, Chronic                           21 (36%)      1 (14%)     56 (97%)                  58 (100%)     7 (100%)    
      Inflammation, Chronic Active                     1 (2%)                                                                       
      Mineralization                                                                                       1 (2%)                   
      Alveolar Epithelium, Hyperplasia, Atypical       1 (2%)                    1 (2%)                    6 (10%)                  
      Alveolar Epithelium, Hyperplasia, Focal          1 (2%)                                                                       
      Alveolar Epithelium, Pigmentation                                                       1 (14%)                               
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    6                                                              
NTP Experiment-Test: 05123-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NICKEL OXIDE                                       Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 04:33:14  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS FEMALE                   0 MG/M3      0 MG/M3      0.62MGM3     0.62MGM3     1.25MGM3     1.25MGM3        
                                                                LUNGTX                     LUNGTX                    LUNGTX         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
RESPIRATORY SYSTEM - CONT                                                                                                           
      Alveolus, Pigmentation                                                    57 (98%)      5 (71%)     58 (100%)     7 (100%)    
      Pleura, Fibrosis                                                                                     1 (2%)                   
   Nose                                               (58)         (7)          (58)         (7)          (57)         (7)          
      Inflammation, Chronic                                                      1 (2%)                                             
      Inflammation, Chronic Active                     1 (2%)                                                                       
      Inflammation, Suppurative                                                  1 (2%)                    2 (4%)                   
   Trachea                                            (58)                      (58)                      (58)                      
      Inflammation, Chronic Active                                                                         2 (3%)                   
      Inflammation, Suppurative                                                                            2 (3%)                   
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                (3)                       (2)                       (6)          (1)          
      Cataract                                                                                             2 (33%)                  
      Hemorrhage                                       1 (33%)                                                                      
      Inflammation, Suppurative                        1 (33%)                                                                      
      Necrosis                                         1 (33%)                                                                      
      Synechia                                                                                             1 (17%)                  
      Bilateral, Cornea, Edema                                                                             1 (17%)                  
      Cornea, Degeneration                                                                                              1 (100%)    
      Cornea, Edema                                                                                        2 (33%)                  
      Lens, Cataract                                   1 (33%)                                                                      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (58)         (7)          (58)         (7)          (58)         (7)          
      Cyst                                                                                                 2 (3%)                   
      Nephropathy                                     40 (69%)                  47 (81%)                  40 (69%)                  
      Cortex, Infiltration Cellular, Lymphocyte                                                                         1 (14%)     
      Cortex, Inflammation, Chronic                    1 (2%)                    1 (2%)                                             
      Cortex, Necrosis, Acute                          1 (2%)                                                                       
      Pelvis, Dilatation                                                                                   1 (2%)                   
   Urinary Bladder                                    (57)                      (58)                      (58)                      
      Calculus Micro Observation Only                  1 (2%)                                              1 (2%)                   
      Edema                                                                                                1 (2%)                   
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    7                                                              
NTP Experiment-Test: 05123-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NICKEL OXIDE                                       Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 04:33:14  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS FEMALE                   2.5MG/M3     2.5MG/M3                                                            
                                                                 LUNGTX                                                             
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially In Study                          58            7                                                               
  Scheduled Sacrifice                                  5            6                                                               
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                24            1                                                               
    Natural Death                                      3                                                                            
  Survivors                                                                                                                         
    Terminal Sacrifice                                26                                                                            
  Animals Examined Microscopically                    58            7                                                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Intestine Large, Rectum                            (58)         (1)                                                              
      Parasite Metazoan                                5 (9%)                                                                       
   Liver                                              (58)         (1)                                                              
      Angiectasis                                      1 (2%)                                                                       
      Basophilic Focus                                34 (59%)                                                                      
      Degeneration, Cystic                             1 (2%)                                                                       
      Eosinophilic Focus                               2 (3%)                                                                       
      Fatty Change                                    15 (26%)                                                                      
      Hepatodiaphragmatic Nodule                       4 (7%)                                                                       
      Inflammation, Chronic                            1 (2%)                                                                       
      Pigmentation, Bile                               1 (2%)                                                                       
      Bile Duct, Hyperplasia                           1 (2%)                                                                       
      Hepatocyte, Hyperplasia                          8 (14%)                                                                      
      Hepatocyte, Necrosis                             4 (7%)                                                                       
   Stomach, Forestomach                               (58)         (1)                                                              
      Hyperkeratosis                                   3 (5%)       1 (100%)                                                        
      Inflammation, Chronic                            1 (2%)                                                                       
      Ulcer                                            1 (2%)                                                                       
   Tooth                                              (1)                                                                           
      Inflammation, Suppurative                        1 (100%)                                                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Heart                                              (58)         (1)                                                              
      Inflammation, Chronic                            1 (2%)                                                                       
      Atrium, Thrombosis                               1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    8                                                              
NTP Experiment-Test: 05123-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NICKEL OXIDE                                       Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 04:33:14  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS FEMALE                   2.5MG/M3     2.5MG/M3                                                            
                                                                 LUNGTX                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (58)         (1)                                                              
      Congestion                                       4 (7%)                                                                       
      Degeneration, Fatty                              8 (14%)                                                                      
      Edema                                            1 (2%)                                                                       
   Adrenal Medulla                                    (57)         (1)                                                              
      Angiectasis                                      1 (2%)                                                                       
      Hyperplasia                                     22 (39%)                                                                      
   Islets, Pancreatic                                 (58)         (1)                                                              
      Hyperplasia                                      1 (2%)                                                                       
   Pituitary Gland                                    (58)         (2)                                                              
      Pars Distalis, Angiectasis                       5 (9%)                                                                       
      Pars Distalis, Cyst                              9 (16%)                                                                      
      Pars Distalis, Hemorrhage                        2 (3%)                                                                       
      Pars Distalis, Hyperplasia                      12 (21%)                                                                      
      Pars Distalis, Hyperplasia, Diffuse                           1 (50%)                                                         
   Thyroid Gland                                      (58)                                                                          
      C-Cell, Hyperplasia                              2 (3%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   Tissue NOS                                         (3)                                                                           
      Abscess                                          1 (33%)                                                                      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Clitoral Gland                                     (54)         (1)                                                              
      Ectasia                                          4 (7%)                                                                       
      Duct, Ectasia                                    1 (2%)                                                                       
   Ovary                                              (58)         (1)                                                              
      Cyst                                             3 (5%)                                                                       
      Fibrosis                                         1 (2%)                                                                       
      Hemorrhage                                       1 (2%)                                                                       
      Bilateral, Cyst                                  1 (2%)                                                                       
   Uterus                                             (58)         (1)                                                              
      Dilatation                                       1 (2%)                                                                       
      Endometrium, Hyperplasia, Cystic                 7 (12%)                                                                      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (58)         (1)                                                              
      Fibrosis                                         1 (2%)                                                                       
      Hyperplasia                                     16 (28%)                                                                      
   Lymph Node                                         (4)                                                                           
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    9                                                              
NTP Experiment-Test: 05123-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NICKEL OXIDE                                       Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 04:33:14  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS FEMALE                   2.5MG/M3     2.5MG/M3                                                            
                                                                 LUNGTX                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
HEMATOPOIETIC SYSTEM - CONT                                                                                                         
      Hyperplasia, Lymphoid                            1 (25%)                                                                      
      Renal, Edema                                     1 (25%)                                                                      
      Renal, Pigmentation                              1 (25%)                                                                      
   Lymph Node, Bronchial                              (56)         (7)                                                              
      Congestion                                       2 (4%)                                                                       
      Hyperplasia, Lymphoid                           15 (27%)      4 (57%)                                                         
      Hyperplasia, Macrophage                          1 (2%)                                                                       
      Pigmentation                                    52 (93%)      6 (86%)                                                         
   Lymph Node, Mandibular                             (53)         (1)                                                              
      Hyperplasia, Lymphoid                            2 (4%)       1 (100%)                                                        
   Lymph Node, Mesenteric                             (58)         (1)                                                              
      Hyperplasia, Lymphoid                            3 (5%)                                                                       
      Pigmentation                                     3 (5%)                                                                       
   Lymph Node, Mediastinal                            (54)         (5)                                                              
      Congestion                                       1 (2%)                                                                       
      Edema                                            1 (2%)                                                                       
      Hyperplasia, Lymphoid                           17 (31%)                                                                      
      Pigmentation                                    47 (87%)      3 (60%)                                                         
   Spleen                                             (58)         (1)                                                              
      Fibrosis                                         1 (2%)                                                                       
      Hyperplasia                                      2 (3%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (58)         (1)                                                              
      Femur, Hyperostosis                              8 (14%)                                                                      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (58)         (1)                                                              
      Cerebrum, Compression                            5 (9%)                                                                       
      Cerebrum, Ventricle, Dilatation                  5 (9%)                                                                       
      Hypothalamus, Compression                        5 (9%)                                                                       
      Ventricle, Dilatation                            3 (5%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   10                                                              
NTP Experiment-Test: 05123-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NICKEL OXIDE                                       Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 04:33:14  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS FEMALE                   2.5MG/M3     2.5MG/M3                                                            
                                                                 LUNGTX                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Larynx                                             (58)         (1)                                                              
      Inflammation, Chronic                            3 (5%)                                                                       
   Lung                                               (58)         (7)                                                              
      Congestion                                       1 (2%)                                                                       
      Cyst                                             1 (2%)                                                                       
      Hemorrhage                                       2 (3%)                                                                       
      Inflammation, Chronic                           58 (100%)     7 (100%)                                                        
      Alveolar Epithelium, Hyperplasia, Atypical       5 (9%)                                                                       
      Alveolar Epithelium, Hyperplasia, Focal          1 (2%)                                                                       
      Alveolus, Pigmentation                          58 (100%)     7 (100%)                                                        
   Nose                                               (58)         (7)                                                              
      Inflammation, Chronic                            1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                (3)                                                                           
      Cataract                                         2 (67%)                                                                      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (58)         (7)                                                              
      Nephropathy                                     42 (72%)                                                                      
      Cortex, Infiltration Cellular, Lymphocyte                     1 (14%)                                                         
      Pelvis, Cyst                                                  1 (14%)                                                         
   Urinary Bladder                                    (58)         (2)                                                              
      Edema, Focal                                                  1 (50%)                                                         
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   11                                                              
NTP Experiment-Test: 05123-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NICKEL OXIDE                                       Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 04:33:14  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     0 MG/M3      0 MG/M3      0.62MGM3     0.62MGM3     1.25MGM3     1.25MGM3        
                                                                LUNGTX                     LUNGTX                    LUNGTX         
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially In Study                          59            6           58            7           58            7           
  Scheduled Sacrifice                                  5            6            5            7            5            7           
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                39                        35                        32                        
    Natural Death                                      1                         3                         6                        
  Survivors                                                                                                                         
    Moribund Sacrifice                                                                                     1                        
    Terminal Sacrifice                                14                        15                        14                        
  Animals Examined Microscopically                    59            6           58            7           58            7           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Intestine Large, Colon                             (59)                      (58)                      (58)                      
      Erosion                                                                    1 (2%)                                             
      Parasite Metazoan                                1 (2%)                                              1 (2%)                   
   Intestine Large, Rectum                            (59)                      (58)                      (57)                      
      Parasite Metazoan                                1 (2%)                    1 (2%)                                             
   Intestine Large, Cecum                             (59)                      (58)                      (57)                      
      Inflammation, Chronic Active                                               1 (2%)                                             
      Inflammation, Suppurative                                                                            1 (2%)                   
      Necrosis                                                                                             1 (2%)                   
      Parasite Metazoan                                                                                    1 (2%)                   
      Ulcer                                                                                                1 (2%)                   
   Intestine Small, Jejunum                           (59)                      (58)                      (58)                      
      Inflammation, Chronic                                                                                1 (2%)                   
      Inflammation, Suppurative                                                  1 (2%)                                             
   Liver                                              (59)                      (58)                      (58)         (1)          
      Angiectasis                                                                                          1 (2%)                   
      Basophilic Focus                                21 (36%)                  15 (26%)                  22 (38%)                  
      Clear Cell Focus                                 1 (2%)                    1 (2%)                                             
      Congestion                                                                                           1 (2%)                   
      Degeneration, Cystic                            16 (27%)                  20 (34%)                  27 (47%)                  
      Developmental Malformation                                                 1 (2%)                                             
      Eosinophilic Focus                               3 (5%)                    4 (7%)                    6 (10%)                  
      Fatty Change                                    13 (22%)                  15 (26%)                  20 (34%)                  
      Hepatodiaphragmatic Nodule                       4 (7%)                    1 (2%)                    2 (3%)       1 (100%)    
      Inflammation, Chronic Active                                                                         1 (2%)                   
      Inflammation, Suppurative                        1 (2%)                                                                       
      Pigmentation, Bile                               1 (2%)                                              1 (2%)                   
      Thrombosis                                       1 (2%)                    1 (2%)                    1 (2%)                   
      Thrombosis, Multiple                             2 (3%)                                                                       
      Bile Duct, Hyperplasia                          17 (29%)                  20 (34%)                  18 (31%)                  
      Hepatocyte, Hyperplasia                          8 (14%)                  14 (24%)                   9 (16%)                  
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   12                                                              
NTP Experiment-Test: 05123-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NICKEL OXIDE                                       Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 04:33:14  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     0 MG/M3      0 MG/M3      0.62MGM3     0.62MGM3     1.25MGM3     1.25MGM3        
                                                                LUNGTX                     LUNGTX                    LUNGTX         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Hepatocyte, Necrosis                             8 (14%)                  14 (24%)                   4 (7%)                   
   Pancreas                                           (59)                      (58)                      (58)                      
      Atrophy                                          1 (2%)                    1 (2%)                                             
      Fibrosis                                                                                             1 (2%)                   
      Acinus, Atrophy                                  5 (8%)                    1 (2%)                    1 (2%)                   
      Acinus, Fibrosis                                 1 (2%)                                                                       
      Acinus, Hyperplasia                              2 (3%)                    1 (2%)                                             
   Stomach, Forestomach                               (59)                      (58)                      (58)                      
      Edema                                            3 (5%)                                                                       
      Hyperkeratosis                                                             1 (2%)                    6 (10%)                  
      Inflammation, Acute                                                                                  1 (2%)                   
      Inflammation, Chronic                                                      1 (2%)                    3 (5%)                   
      Inflammation, Chronic Active                                                                         1 (2%)                   
      Inflammation, Suppurative                        1 (2%)                                                                       
      Ulcer                                            1 (2%)                    3 (5%)                    3 (5%)                   
      Ulcer, Multiple                                  2 (3%)                                                                       
   Stomach, Glandular                                 (59)                      (58)                      (58)                      
      Erosion                                                                    1 (2%)                    1 (2%)                   
      Inflammation, Chronic                                                      1 (2%)                                             
      Inflammation, Chronic Active                                               1 (2%)                                             
      Inflammation, Suppurative                        1 (2%)                    1 (2%)                    1 (2%)                   
      Pigmentation                                                                                         1 (2%)                   
      Ulcer                                            1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Blood Vessel                                       (2)                                                 (1)                       
      Aorta, Mineralization                            2 (100%)                                            1 (100%)                 
   Heart                                              (59)                      (58)                      (58)                      
      Fibrosis                                                                   1 (2%)                                             
      Inflammation, Chronic                                                                                1 (2%)                   
      Inflammation, Suppurative                        2 (3%)                                                                       
      Atrium, Thrombosis                               4 (7%)                    6 (10%)                   4 (7%)                   
      Epicardium, Degeneration                                                   1 (2%)                                             
      Myocardium, Mineralization                       1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (59)                      (58)                      (58)                      
      Angiectasis                                                                2 (3%)                                             
      Degeneration, Fatty                              2 (3%)                    1 (2%)                    6 (10%)                  
   Adrenal Medulla                                    (59)                      (57)                      (58)                      
      Cyst                                                                       1 (2%)                                             
      Degeneration, Fatty                              1 (2%)                                                                       
      Hyperplasia                                     25 (42%)                  27 (47%)                  27 (47%)                  
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   13                                                              
NTP Experiment-Test: 05123-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NICKEL OXIDE                                       Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 04:33:14  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     0 MG/M3      0 MG/M3      0.62MGM3     0.62MGM3     1.25MGM3     1.25MGM3        
                                                                LUNGTX                     LUNGTX                    LUNGTX         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ENDOCRINE SYSTEM - CONT                                                                                                             
   Islets, Pancreatic                                 (59)                      (58)                      (58)                      
      Hyperplasia                                                                3 (5%)                    2 (3%)                   
   Parathyroid Gland                                  (54)                      (55)                      (54)                      
      Hyperplasia                                      2 (4%)                                              2 (4%)                   
   Pituitary Gland                                    (58)                      (57)                      (57)                      
      Angiectasis                                      2 (3%)                    3 (5%)                                             
      Hyperplasia                                                                1 (2%)                                             
      Pars Distalis, Angiectasis                                                 1 (2%)                                             
      Pars Distalis, Cyst                              2 (3%)                                                                       
      Pars Distalis, Hyperplasia                       4 (7%)                    3 (5%)                    6 (11%)                  
      Pars Distalis, Necrosis                                                    1 (2%)                                             
      Pars Distalis, Pigmentation                                                                          1 (2%)                   
   Thyroid Gland                                      (59)                      (58)                      (57)                      
      Hyperplasia, Cystic                                                                                  1 (2%)                   
      Infiltration Cellular, Lymphocyte                                                                    1 (2%)                   
      C-Cell, Hyperplasia                              1 (2%)                    1 (2%)                    2 (4%)                   
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   Tissue NOS                                         (3)                       (2)                       (2)                       
      Developmental Malformation                                                 1 (50%)                                            
      Oral, Inflammation, Chronic Active               1 (33%)                                                                      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Coagulating Gland                                  (4)                                                                           
      Inflammation, Chronic                            1 (25%)                                                                      
      Inflammation, Suppurative                        2 (50%)                                                                      
   Epididymis                                         (59)                      (58)                      (58)                      
      Spermatocele                                     1 (2%)                                              2 (3%)                   
   Preputial Gland                                    (59)                      (58)                      (58)                      
      Ectasia                                          2 (3%)                    3 (5%)                    4 (7%)                   
      Inflammation, Suppurative                        3 (5%)                    1 (2%)                                             
      Bilateral, Ectasia                                                         1 (2%)                                             
      Duct, Ectasia                                                              1 (2%)                                             
   Prostate                                           (58)                      (58)                      (58)                      
      Hyperplasia                                                                                          1 (2%)                   
      Inflammation, Chronic                            3 (5%)                    3 (5%)                                             
      Inflammation, Chronic Active                                               1 (2%)                    1 (2%)                   
      Inflammation, Suppurative                        3 (5%)                    1 (2%)                    4 (7%)                   
   Seminal Vesicle                                    (59)                      (58)                      (58)                      
      Atrophy                                          3 (5%)                                              3 (5%)                   
      Ectasia                                          1 (2%)                                              1 (2%)                   
      Inflammation, Suppurative                                                                            2 (3%)                   
   Testes                                             (59)                      (58)                      (58)                      
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   14                                                              
NTP Experiment-Test: 05123-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NICKEL OXIDE                                       Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 04:33:14  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     0 MG/M3      0 MG/M3      0.62MGM3     0.62MGM3     1.25MGM3     1.25MGM3        
                                                                LUNGTX                     LUNGTX                    LUNGTX         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
GENITAL SYSTEM - CONT                                                                                                               
      Atrophy                                         11 (19%)                   7 (12%)                   7 (12%)                  
      Hemorrhage                                                                                           1 (2%)                   
      Bilateral, Atrophy                                                         1 (2%)                    2 (3%)                   
      Interstitial Cell, Hyperplasia                   8 (14%)                   4 (7%)                    3 (5%)                   
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (59)                      (58)                      (58)                      
      Fibrosis                                         7 (12%)                   4 (7%)                    5 (9%)                   
      Hyperplasia                                     24 (41%)                  35 (60%)                  19 (33%)                  
   Lymph Node                                         (16)                      (19)                      (16)         (1)          
      Pigmentation                                                               4 (21%)                                1 (100%)    
      Iliac, Congestion                                                          2 (11%)                                            
      Iliac, Ectasia                                                                                       1 (6%)                   
      Iliac, Hyperplasia, Lymphoid                     1 (6%)                    1 (5%)                    1 (6%)                   
      Iliac, Pigmentation                                                                                  1 (6%)                   
      Pancreatic, Congestion                                                     1 (5%)                                             
      Pancreatic, Hyperplasia, Lymphoid                1 (6%)                                                                       
      Renal, Congestion                                                          2 (11%)                   1 (6%)                   
      Renal, Hyperplasia, Lymphoid                     1 (6%)                    2 (11%)                   1 (6%)                   
      Renal, Pigmentation                                                        3 (16%)                                            
   Lymph Node, Bronchial                              (57)         (6)          (56)         (7)          (58)         (7)          
      Congestion                                       1 (2%)                    1 (2%)                                             
      Congestion, Chronic                                           1 (17%)                                                         
      Edema                                                                      1 (2%)                                             
      Hyperplasia, Lymphoid                                         1 (17%)      7 (13%)                  14 (24%)      7 (100%)    
      Hyperplasia, Macrophage                          1 (2%)                                                                       
      Pigmentation                                                              50 (89%)                  56 (97%)      7 (100%)    
   Lymph Node, Mandibular                             (54)                      (56)                      (55)                      
      Hyperplasia, Lymphoid                            5 (9%)                    4 (7%)                    6 (11%)                  
   Lymph Node, Mesenteric                             (59)                      (58)                      (58)                      
      Congestion                                                                 2 (3%)                                             
      Edema                                                                      1 (2%)                                             
      Hyperplasia                                                                1 (2%)                                             
      Hyperplasia, Lymphoid                            1 (2%)                    2 (3%)                                             
   Lymph Node, Mediastinal                            (52)         (6)          (57)         (6)          (57)         (6)          
      Congestion                                       1 (2%)                    2 (4%)       1 (17%)                               
      Ectasia                                          1 (2%)                                              1 (2%)                   
      Hyperplasia, Lymphoid                            5 (10%)                   8 (14%)                  13 (23%)      3 (50%)     
      Hyperplasia, Plasma Cell                         3 (6%)                    2 (4%)                                             
      Pigmentation                                                              36 (63%)                  47 (82%)      4 (67%)     
   Spleen                                             (59)                      (58)                      (58)                      
      Congestion                                                                                           1 (2%)                   
      Developmental Malformation                       1 (2%)                                              1 (2%)                   
      Fibrosis                                        11 (19%)                   7 (12%)                  15 (26%)                  
      Infarct                                          4 (7%)                    6 (10%)                   3 (5%)                   
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   15                                                              
NTP Experiment-Test: 05123-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NICKEL OXIDE                                       Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 04:33:14  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     0 MG/M3      0 MG/M3      0.62MGM3     0.62MGM3     1.25MGM3     1.25MGM3        
                                                                LUNGTX                     LUNGTX                    LUNGTX         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
HEMATOPOIETIC SYSTEM - CONT                                                                                                         
      Necrosis                                                                   1 (2%)                    1 (2%)                   
      Capsule, Fibrosis                                                                                    1 (2%)                   
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (59)                      (58)                      (58)                      
      Hyperplasia                                      1 (2%)                                                                       
      Duct, Ectasia                                                              1 (2%)                                             
   Skin                                               (13)                      (4)                       (14)                      
      Alopecia                                                                                             1 (7%)                   
      Cyst Epithelial Inclusion                        2 (15%)                   2 (50%)                   2 (14%)                  
      Hyperkeratosis                                   1 (8%)                                              1 (7%)                   
      Necrosis                                                                                             1 (7%)                   
      Pigmentation                                     1 (8%)                                                                       
      Epidermis, Hyperplasia                                                                               1 (7%)                   
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (59)                      (58)                      (58)                      
      Hyperostosis                                                               1 (2%)                    2 (3%)                   
      Femur, Hyperostosis                                                        2 (3%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (59)                      (58)                      (58)                      
      Cerebellum, Compression                                                    1 (2%)                    1 (2%)                   
      Cerebellum, Hemorrhage                                                     2 (3%)                    3 (5%)                   
      Cerebellum, Ventricle, Dilatation                                                                    1 (2%)                   
      Cerebrum, Compression                                                      5 (9%)                    7 (12%)                  
      Cerebrum, Degeneration                           1 (2%)                                                                       
      Cerebrum, Hemorrhage                                                       1 (2%)                    1 (2%)                   
      Cerebrum, Necrosis                               1 (2%)                                                                       
      Cerebrum, Ventricle, Dilatation                                                                      2 (3%)                   
      Hypothalamus, Compression                        8 (14%)                                             1 (2%)                   
      Pons, Compression                                2 (3%)                                                                       
      Thalamus, Degeneration                           1 (2%)                                                                       
      Ventricle, Dilatation                            2 (3%)                    1 (2%)                    1 (2%)                   
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   16                                                              
NTP Experiment-Test: 05123-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NICKEL OXIDE                                       Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 04:33:14  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     0 MG/M3      0 MG/M3      0.62MGM3     0.62MGM3     1.25MGM3     1.25MGM3        
                                                                LUNGTX                     LUNGTX                    LUNGTX         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Larynx                                             (57)                      (57)                      (57)                      
      Inflammation, Chronic                            2 (4%)                                                                       
      Inflammation, Suppurative                        1 (2%)                                                                       
   Lung                                               (59)         (6)          (58)         (7)          (58)         (7)          
      Hemorrhage                                                                 1 (2%)                    1 (2%)                   
      Inflammation, Chronic                           32 (54%)      3 (50%)     58 (100%)                 58 (100%)     7 (100%)    
      Mineralization                                   1 (2%)                                                                       
      Alveolar Epithelium, Hyperplasia, Atypical                                                           4 (7%)                   
      Alveolar Epithelium, Hyperplasia, Focal                                    2 (3%)                    1 (2%)                   
      Alveolar Epithelium, Metaplasia, Squamous                                  1 (2%)                                             
      Alveolus, Pigmentation                           1 (2%)                   58 (100%)     6 (86%)     58 (100%)     7 (100%)    
   Nose                                               (59)         (6)          (58)         (7)          (58)         (7)          
      Inflammation, Chronic Active                     1 (2%)                    2 (3%)                    2 (3%)                   
      Inflammation, Suppurative                        5 (8%)                    2 (3%)                    3 (5%)                   
      Respiratory Epithelium, Inflammation, Focal,                                                                                  
           Suppurative                                 1 (2%)                                                                       
   Trachea                                            (58)                      (58)                      (58)                      
      Inflammation, Focal, Suppurative                 1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                (12)                      (5)                       (3)                       
      Cataract                                         5 (42%)                   3 (60%)                   1 (33%)                  
      Anterior Chamber, Cornea, Inflammation,                                                                                       
          Suppurative                                  1 (8%)                                                                       
      Bilateral, Cornea, Edema                         1 (8%)                                                                       
      Cornea, Edema                                    2 (17%)                                                                      
      Cornea, Inflammation, Suppurative                                          1 (20%)                                            
      Lids, Inflammation, Chronic Active                                         1 (20%)                                            
      Retina, Degeneration                             1 (8%)                                                                       
      Sclera, Metaplasia, Osseous                      1 (8%)                                                                       
      Vitreous, Inflammation, Chronic                  1 (8%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (59)         (6)          (58)         (7)          (58)         (7)          
      Cyst                                             2 (3%)                    1 (2%)                    2 (3%)                   
      Infarct                                                                    1 (2%)                                             
      Necrosis                                                                                             1 (2%)                   
      Nephropathy                                     52 (88%)                  54 (93%)                  53 (91%)                  
      Pigmentation                                                               1 (2%)                                             
      Bilateral, Nephropathy                           1 (2%)                                                                       
      Bilateral, Cortex, Cyst                                                    1 (2%)                                             
      Cortex, Cyst                                     2 (3%)                                                                       
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   17                                                              
NTP Experiment-Test: 05123-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NICKEL OXIDE                                       Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 04:33:14  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     0 MG/M3      0 MG/M3      0.62MGM3     0.62MGM3     1.25MGM3     1.25MGM3        
                                                                LUNGTX                     LUNGTX                    LUNGTX         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
URINARY SYSTEM - CONT                                                                                                               
      Medulla, Cyst                                                                                        1 (2%)                   
      Pelvis, Degeneration                                                                                 1 (2%)                   
      Pelvis, Inflammation, Suppurative                                                                    1 (2%)                   
   Urinary Bladder                                    (59)         (3)          (58)         (3)          (58)         (5)          
      Calculus Micro Observation Only                  5 (8%)       3 (100%)     2 (3%)       3 (100%)     4 (7%)       5 (100%)    
      Inflammation, Subacute                           1 (2%)                                                                       
      Metaplasia, Squamous                                                                                 1 (2%)                   
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   18                                                              
NTP Experiment-Test: 05123-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NICKEL OXIDE                                       Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 04:33:14  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     2.5MG/M3     2.5MG/M3                                                            
                                                                 LUNGTX                                                             
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially In Study                          58            7                                                               
  Scheduled Sacrifice                                  5            7                                                               
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                36                                                                            
    Natural Death                                      4                                                                            
  Survivors                                                                                                                         
    Natural Death                                      1                                                                            
    Terminal Sacrifice                                11                                                                            
  Other                                                1                                                                            
  Animals Examined Microscopically                    57            7                                                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Intestine Large, Colon                             (57)                                                                          
      Parasite Metazoan                                1 (2%)                                                                       
   Intestine Small, Jejunum                           (57)                                                                          
      Inflammation, Chronic Active                     1 (2%)                                                                       
   Liver                                              (57)                                                                          
      Basophilic Focus                                20 (35%)                                                                      
      Congestion                                       4 (7%)                                                                       
      Degeneration, Cystic                            28 (49%)                                                                      
      Developmental Malformation                       1 (2%)                                                                       
      Eosinophilic Focus                               7 (12%)                                                                      
      Fatty Change                                    11 (19%)                                                                      
      Hemorrhage                                       1 (2%)                                                                       
      Hepatodiaphragmatic Nodule                       4 (7%)                                                                       
      Infarct                                          1 (2%)                                                                       
      Mixed Cell Focus                                 1 (2%)                                                                       
      Thrombosis                                       1 (2%)                                                                       
      Bile Duct, Hyperplasia                          25 (44%)                                                                      
      Hepatocyte, Hyperplasia                         11 (19%)                                                                      
      Hepatocyte, Necrosis                            10 (18%)                                                                      
      Portal Vein, Thrombosis                          1 (2%)                                                                       
   Pancreas                                           (57)                                                                          
      Congestion                                       1 (2%)                                                                       
      Acinus, Atrophy                                  2 (4%)                                                                       
   Stomach, Forestomach                               (57)                                                                          
      Hyperkeratosis                                   1 (2%)                                                                       
   Stomach, Glandular                                 (57)                                                                          
      Inflammation, Chronic                            1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   19                                                              
NTP Experiment-Test: 05123-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NICKEL OXIDE                                       Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 04:33:14  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     2.5MG/M3     2.5MG/M3                                                            
                                                                 LUNGTX                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Heart                                              (57)                                                                          
      Infarct                                          1 (2%)                                                                       
      Inflammation, Chronic                            1 (2%)                                                                       
      Atrium, Congestion                               1 (2%)                                                                       
      Atrium, Thrombosis                               4 (7%)                                                                       
      Ventricle, Fibrosis                              1 (2%)                                                                       
      Ventricle, Inflammation, Chronic                 1 (2%)                                                                       
      Ventricle, Mineralization                        1 (2%)                                                                       
      Ventricle, Thrombosis                            1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (57)                                                                          
      Degeneration, Fatty                              3 (5%)                                                                       
   Adrenal Medulla                                    (57)                                                                          
      Hyperplasia                                     26 (46%)                                                                      
   Islets, Pancreatic                                 (57)                                                                          
      Hyperplasia                                      1 (2%)                                                                       
   Parathyroid Gland                                  (54)                                                                          
      Hyperplasia                                      2 (4%)                                                                       
   Pituitary Gland                                    (57)                                                                          
      Hyperplasia                                      1 (2%)                                                                       
      Pars Distalis, Angiectasis                       3 (5%)                                                                       
      Pars Distalis, Cyst                              2 (4%)                                                                       
      Pars Distalis, Hyperplasia                      11 (19%)                                                                      
   Thyroid Gland                                      (57)                                                                          
      C-Cell, Hyperplasia                              2 (4%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Coagulating Gland                                  (1)                                                                           
      Inflammation, Suppurative                        1 (100%)                                                                     
   Preputial Gland                                    (56)                                                                          
      Ectasia                                          1 (2%)                                                                       
      Hyperplasia, Glandular                           1 (2%)                                                                       
      Inflammation, Suppurative                        3 (5%)                                                                       
   Prostate                                           (57)                                                                          
      Inflammation, Chronic                            1 (2%)                                                                       
      Inflammation, Chronic Active                     1 (2%)                                                                       
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   20                                                              
NTP Experiment-Test: 05123-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NICKEL OXIDE                                       Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 04:33:14  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     2.5MG/M3     2.5MG/M3                                                            
                                                                 LUNGTX                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
GENITAL SYSTEM - CONT                                                                                                               
   Testes                                             (57)                                                                          
      Atrophy                                         10 (18%)                                                                      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (57)                                                                          
      Fibrosis                                         4 (7%)                                                                       
      Hyperplasia                                     36 (63%)                                                                      
   Lymph Node                                         (15)                                                                          
      Hyperplasia, Macrophage                          1 (7%)                                                                       
      Iliac, Pigmentation                              1 (7%)                                                                       
      Renal, Edema                                     1 (7%)                                                                       
      Renal, Pigmentation                              2 (13%)                                                                      
   Lymph Node, Bronchial                              (57)         (7)                                                              
      Congestion                                       3 (5%)                                                                       
      Edema                                            1 (2%)                                                                       
      Hyperplasia                                                   1 (14%)                                                         
      Hyperplasia, Lymphoid                           22 (39%)      4 (57%)                                                         
      Pigmentation                                    56 (98%)      7 (100%)                                                        
   Lymph Node, Mandibular                             (56)                                                                          
      Hyperplasia, Lymphoid                            3 (5%)                                                                       
   Lymph Node, Mesenteric                             (56)                                                                          
      Hyperplasia, Lymphoid                            1 (2%)                                                                       
   Lymph Node, Mediastinal                            (56)         (6)                                                              
      Congestion                                       3 (5%)                                                                       
      Hyperplasia, Lymphoid                           19 (34%)                                                                      
      Hyperplasia, Plasma Cell                         1 (2%)                                                                       
      Pigmentation                                    54 (96%)      3 (50%)                                                         
   Spleen                                             (57)                                                                          
      Fibrosis                                        10 (18%)                                                                      
      Infarct                                          2 (4%)                                                                       
   Thymus                                             (53)                                                                          
      Congestion                                       1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (57)                                                                          
      Ectasia                                          1 (2%)                                                                       
   Skin                                               (7)                                                                           
      Cyst Epithelial Inclusion                        1 (14%)                                                                      
      Pigmentation                                     1 (14%)                                                                      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   21                                                              
NTP Experiment-Test: 05123-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NICKEL OXIDE                                       Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 04:33:14  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     2.5MG/M3     2.5MG/M3                                                            
                                                                 LUNGTX                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (57)                                                                          
      Hyperostosis                                     2 (4%)                                                                       
      Femur, Hyperostosis                              4 (7%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (57)                                                                          
      Hemorrhage                                       1 (2%)                                                                       
      Cerebellum, Compression                          1 (2%)                                                                       
      Cerebrum, Compression                            5 (9%)                                                                       
      Cerebrum, Necrosis                               1 (2%)                                                                       
      Cerebrum, Ventricle, Dilatation                  3 (5%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Larynx                                             (56)                                                                          
      Inflammation, Chronic                            1 (2%)                                                                       
      Inflammation, Chronic Active                     2 (4%)                                                                       
   Lung                                               (57)         (7)                                                              
      Congestion                                       1 (2%)                                                                       
      Cyst                                             1 (2%)                                                                       
      Hemorrhage                                       2 (4%)                                                                       
      Inflammation, Chronic                           57 (100%)     7 (100%)                                                        
      Alveolar Epithelium, Hyperplasia, Atypical       3 (5%)                                                                       
      Alveolus, Pigmentation                          57 (100%)     6 (86%)                                                         
   Nose                                               (57)         (7)                                                              
      Inflammation, Chronic Active                     5 (9%)                                                                       
      Inflammation, Suppurative                        2 (4%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                (5)                                                                           
      Cataract                                         3 (60%)                                                                      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (57)         (7)                                                              
      Cyst                                             1 (2%)                                                                       
      Fibrosis                                         1 (2%)                                                                       
      Infarct                                          2 (4%)                                                                       
      Nephropathy                                     47 (82%)                                                                      
      Cortex, Cyst                                     1 (2%)                                                                       
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   22                                                              
NTP Experiment-Test: 05123-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NICKEL OXIDE                                       Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 04:33:14  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     2.5MG/M3     2.5MG/M3                                                            
                                                                 LUNGTX                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
URINARY SYSTEM - CONT                                                                                                               
      Medulla, Congestion                              1 (2%)                                                                       
   Urinary Bladder                                    (57)         (4)                                                              
      Calculus Micro Observation Only                               4 (100%)                                                        
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   23                                                              
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