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TDMS Study 05123-06 Pathology Tables


                              INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)
                                                            NICKEL OXIDE


NTP Experiment-Test: 05123-06                                                                                     Report: PEIRPT05
Study Type: CHRONIC                                                                                               Date: 05/20/95
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 05:20:49




       Facility:  Lovelace Inhalation Toxicology Research Institute

       Chemical CAS #:  1313-99-1

       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: 05123-06  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                            NICKEL OXIDE                                       Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 05:20:49  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE FEMALE                        0 MG/M3      0 MG/M3      1.25MGM3     1.25MGM3     2.5MG/M3     2.5MG/M3        
                                                                  LUNGTX                    LUNGTX                    LUNGTX        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially in Study                          60           20           60           20           60           20           
  Scheduled Sacrifice                                              10                        10                        10           
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                12            3           15            3            6            3           
    Natural Death                                      6            1            5            3           10            1           
    Accidently Killed                                  1                                                   1                        
  Survivors                                                                                                                         
    Moribund Sacrifice                                                           2                                                  
    Terminal Sacrifice                                40                        38                        42                        
    Natural Death                                      1                                                                            
    Terminal Sacrifice                                              6                         4                         6           
  Other                                                                                                    1                        
  Animals Examined Microscopically                    60           14           60           16           59           14           
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Gallbladder                                        (57)         (8)          (56)         (8)          (54)         (8)          
   Intestine Large, Colon                             (57)         (8)          (58)         (8)          (55)         (8)          
   Intestine Large, Rectum                            (52)         (8)          (47)         (8)          (40)         (8)          
   Intestine Large, Cecum                             (57)         (8)          (57)         (8)          (54)         (8)          
   Intestine Small, Duodenum                          (57)         (8)          (56)         (9)          (53)         (8)          
   Intestine Small, Jejunum                           (56)         (8)          (56)         (8)          (53)         (8)          
   Intestine Small, Ileum                             (55)         (8)          (54)         (8)          (53)         (8)          
   Liver                                              (60)         (9)          (60)         (11)         (59)         (9)          
      Hemangiosarcoma                                                                                      1 (2%)                   
      Hemangiosarcoma, Multiple                                                  1 (2%)                                             
      Hemangiosarcoma, Metastatic, Uterus                                        1 (2%)                                             
      Hepatocellular Carcinoma                         7 (12%)                  10 (17%)                   6 (10%)      2 (22%)     
      Hepatocellular Carcinoma, Multiple               1 (2%)                                                                       
      Hepatocellular Adenoma                           5 (8%)                    7 (12%)      1 (9%)       7 (12%)      1 (11%)     
      Hepatocellular Adenoma, Multiple                                                                     1 (2%)                   
      Hepatocellular Adenoma, Multiple, Multiple       1 (2%)                                                                       
      Histiocytic Sarcoma                              1 (2%)                                                                       
   Mesentery                                          (2)                       (2)                       (1)                       
      Hemangiosarcoma                                  1 (50%)                                                                      
   Pancreas                                           (60)         (9)          (60)         (11)         (58)         (9)          
   Salivary Glands                                    (60)         (9)          (60)         (11)         (59)         (9)          
   Stomach, Forestomach                               (60)         (9)          (59)         (9)          (58)         (9)          
      Squamous Cell Carcinoma                          1 (2%)                                                                       
      Squamous Cell Papilloma                          1 (2%)                                                                       
   Stomach, Glandular                                 (59)         (9)          (59)         (9)          (58)         (9)          
____________________________________________________________________________________________________________________________________
                                                             Page   2                                                               
NTP Experiment-Test: 05123-06  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                            NICKEL OXIDE                                       Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 05:20:49  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE FEMALE                        0 MG/M3      0 MG/M3      1.25MGM3     1.25MGM3     2.5MG/M3     2.5MG/M3        
                                                                  LUNGTX                    LUNGTX                    LUNGTX        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Heart                                              (60)         (9)          (60)         (11)         (59)         (9)          
      Alveolar/Bronchiolar Carcinoma, Metastatic,                                                                                   
           Lung                                        1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (60)         (9)          (60)         (11)         (59)         (9)          
   Adrenal Medulla                                    (60)         (7)          (59)         (11)         (59)         (9)          
      Pheochromocytoma Malignant                       2 (3%)                                                                       
      Pheochromocytoma Benign                          1 (2%)                                              1 (2%)                   
   Pituitary Gland                                    (59)         (9)          (60)         (11)         (57)         (9)          
      Pars Distalis, Adenoma                           6 (10%)                   8 (13%)      1 (9%)       8 (14%)                  
      Pars Distalis, Carcinoma                         1 (2%)                                                                       
      Pars Intermedia, Adenoma                                                   1 (2%)                    1 (2%)                   
   Thyroid Gland                                      (59)         (8)          (60)         (11)         (59)         (9)          
      Bilateral, Follicular Cell, Adenoma                                                                  1 (2%)                   
      Follicular Cell, Adenoma                         2 (3%)                    1 (2%)                                             
      Follicular Cell, Carcinoma                       1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   Tissue NOS                                         (1)                       (1)          (1)          (1)                       
      Alveolar/Bronchiolar Carcinoma, Metastatic,                                                                                   
           Lung                                                                  1 (100%)                                           
      Fat, Hemangiosarcoma                                                                                 1 (100%)                 
      Thoracic, Alveolar/Bronchiolar Carcinoma,                                                                                     
           Metastatic, Lung                            1 (100%)                                                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Clitoral Gland                                     (54)         (8)          (56)         (11)         (53)         (9)          
      Duct, Adenoma                                                              1 (2%)                                             
   Ovary                                              (57)         (9)          (60)         (11)         (57)         (8)          
      Cystadenoma                                      1 (2%)                                              3 (5%)                   
      Granulosa-Theca Tumor Benign                                                                         1 (2%)                   
      Teratoma Benign                                  1 (2%)       1 (11%)                   1 (9%)                                
      Thecoma Benign                                   1 (2%)                                                                       
   Uterus                                             (60)         (9)          (60)         (11)         (58)         (9)          
      Carcinoma                                                                  1 (2%)                                             
      Hemangioma                                                                                           1 (2%)                   
      Hemangiosarcoma                                                            1 (2%)       1 (9%)       1 (2%)                   
      Histiocytic Sarcoma                              1 (2%)                                                                       
                                                             Page   3                                                               
NTP Experiment-Test: 05123-06  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                            NICKEL OXIDE                                       Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 05:20:49  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE FEMALE                        0 MG/M3      0 MG/M3      1.25MGM3     1.25MGM3     2.5MG/M3     2.5MG/M3        
                                                                  LUNGTX                    LUNGTX                    LUNGTX        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
GENITAL SYSTEM - cont                                                                                                               
      Leiomyoma                                        1 (2%)                                                                       
      Polyp Stromal                                    2 (3%)                    4 (7%)                                             
      Sarcoma Stromal                                  1 (2%)                                              1 (2%)                   
      Cervix, Hemangiosarcoma                                                    1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (60)         (9)          (59)         (11)         (58)         (9)          
      Hemangiosarcoma                                                                                      1 (2%)                   
      Hemangiosarcoma, Metastatic, Spleen                                                                  1 (2%)                   
   Lymph Node                                         (15)                      (8)          (1)          (9)          (1)          
      Axillary, Hemangiosarcoma                        1 (7%)                                              1 (11%)                  
   Lymph Node, Bronchial                              (53)         (9)          (58)         (14)         (56)         (13)         
      Alveolar/Bronchiolar Carcinoma, Metastatic,                                                                                   
           Lung                                        1 (2%)                    2 (3%)                                             
   Lymph Node, Mandibular                             (58)         (8)          (58)         (11)         (55)         (9)          
      Sarcoma, Metastatic, Skin                                                               1 (9%)                                
   Lymph Node, Mesenteric                             (53)         (6)          (58)         (10)         (51)         (8)          
      Hemangiosarcoma, Metastatic, Liver                                                                   1 (2%)                   
   Lymph Node, Mediastinal                            (35)         (2)          (27)         (7)          (31)         (5)          
      Alveolar/Bronchiolar Carcinoma, Metastatic                                 1 (4%)                                             
      Alveolar/Bronchiolar Carcinoma, Metastatic,                                                                                   
           Lung                                        1 (3%)                    1 (4%)                                             
   Spleen                                             (60)         (9)          (60)         (12)         (59)         (9)          
      Hemangiosarcoma                                  2 (3%)                    2 (3%)                    5 (8%)                   
   Thymus                                             (56)         (8)          (55)         (11)         (57)         (8)          
      Alveolar/Bronchiolar Carcinoma, Metastatic                                 1 (2%)                                             
      Alveolar/Bronchiolar Carcinoma, Metastatic,                                                                                   
           Lung                                        2 (4%)                    1 (2%)                                             
      Histiocytic Sarcoma                              1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (59)         (9)          (60)         (11)         (59)         (9)          
      Adenoma                                                                    1 (2%)                                             
      Carcinoma                                        2 (3%)                    3 (5%)                                             
   Skin                                               (4)                       (6)          (2)          (5)          (1)          
      Hemangiosarcoma                                                            1 (17%)                                            
      Melanoma NOS                                                               1 (17%)                                            
      Sarcoma                                                                                 1 (50%)      1 (20%)                  
      Pinna, Sarcoma                                                                          1 (50%)                               
      Sebaceous Gland, Adenoma                                                                             1 (20%)                  
      Subcutaneous Tissue, Hemangiosarcoma             1 (25%)                   1 (17%)                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                             Page   4                                                               
NTP Experiment-Test: 05123-06  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                            NICKEL OXIDE                                       Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 05:20:49  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE FEMALE                        0 MG/M3      0 MG/M3      1.25MGM3     1.25MGM3     2.5MG/M3     2.5MG/M3        
                                                                  LUNGTX                    LUNGTX                    LUNGTX        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (60)         (9)          (59)         (11)         (59)         (9)          
      Alveolar/Bronchiolar Carcinoma, Metastatic,                                                                                   
           Lung                                                                  1 (2%)                                             
   Skeletal Muscle                                    (3)                                                                           
      Alveolar/Bronchiolar Carcinoma, Metastatic,                                                                                   
           Lung                                        1 (33%)                                                                      
      Rhabdomyosarcoma                                 1 (33%)                                                                      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (60)         (9)          (60)         (11)         (59)         (9)          
      Carcinoma, Metastatic                            1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Larynx                                             (58)         (9)          (57)         (11)         (58)         (9)          
   Lung                                               (60)         (14)         (60)         (16)         (59)         (14)         
      Alveolar/Bronchiolar Adenoma                     2 (3%)                    2 (3%)                   10 (17%)      1 (7%)      
      Alveolar/Bronchiolar Adenoma, Multiple                                     2 (3%)                                             
      Alveolar/Bronchiolar Carcinoma                   4 (7%)                   10 (17%)                   4 (7%)                   
      Alveolar/Bronchiolar Carcinoma, Multiple                                                1 (6%)                                
      Basosquamous Tumor Malignant, Metastatic, Ear    1 (2%)                                                                       
      Hepatocellular Carcinoma, Metastatic                                       1 (2%)                    1 (2%)                   
      Hepatocellular Carcinoma, Metastatic, Liver      1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Ear                                                (2)                       (1)                       (1)                       
      Basosquamous Tumor Malignant                     1 (50%)                                                                      
      Fibrosarcoma                                                                                         1 (100%)                 
      External Ear, Fibrosarcoma                       1 (50%)                                                                      
   Harderian Gland                                                              (1)                       (2)                       
      Adenoma                                                                    1 (100%)                  2 (100%)                 
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (60)         (14)         (60)         (16)         (59)         (14)         
   Urinary Bladder                                    (60)         (8)          (58)         (9)          (56)         (9)          
                                                             Page   5                                                               
NTP Experiment-Test: 05123-06  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                            NICKEL OXIDE                                       Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 05:20:49  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE FEMALE                        0 MG/M3      0 MG/M3      1.25MGM3     1.25MGM3     2.5MG/M3     2.5MG/M3        
                                                                  LUNGTX                    LUNGTX                    LUNGTX        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
 SYSTEMIC LESIONS                                                                                                                   
   Multiple Organs                                   *(60)        *(14)        *(60)        *(16)        *(59)        *(14)         
      Histiocytic Sarcoma                              2 (3%)                                                                       
      Lymphoma Malignant                              13 (22%)                  11 (18%)      1 (6%)       9 (15%)                  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
     *   Number of animals with any tissue examined microscopically                                                                 
                                                             Page   6                                                               
NTP Experiment-Test: 05123-06  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                            NICKEL OXIDE                                       Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 05:20:49  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE FEMALE                        0 MG/M3      0 MG/M3      1.25MGM3     1.25MGM3     2.5MG/M3     2.5MG/M3        
                                                                  LUNGTX                    LUNGTX                    LUNGTX        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
TUMOR SUMMARY                                                                                                                       
                                                                                                                                    
   Total Animals with Primary Neoplasms (b)            36           1          44           6          42           4               
     Total Primary Neoplasms                           67           1          71           8          69           4               
                                                                                                                                    
   Total Animals with Benign Neoplasms                 20           1          25           3          27           2               
     Total Benign Neoplasms                            24           1          28           3          37           2               
                                                                                                                                    
   Total Animals with Malignant Neoplasms              30                      33           4          26           2               
     Total Malignant Neoplasms                         43                      42           5          32           2               
                                                                                                                                    
   Total Animals with Metastatic Neoplasms              5                       5           1           3                           
     Total Metastatic Neoplasm                         10                      10           1           3                           
                                                                                                                                    
   Total Animals with Malignant Neoplasms                                                                                           
   Uncertain Primary Site                                                                                                           
                                                                                                                                    
   Total Animals with Neoplasms Uncertain-                                                                                          
   Benign or Malignant                                                          1                                                   
     Total Uncertain Neoplasms                                                  1                                                   
                                                                                                                                    
____________________________________________________________________________________________________________________________________
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Primary tumors: all tumors except metastatic tumors                                                                              
                                                             Page   7                                                               
NTP Experiment-Test: 05123-06  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                            NICKEL OXIDE                                       Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 05:20:49  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE FEMALE                        5.0MG/M3     5.0MG/M3                                                            
                                                                  LUNGTX                                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially in Study                          60           20                                                               
  Scheduled Sacrifice                                              10                                                               
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                12            4                                                               
    Natural Death                                      9            1                                                               
  Survivors                                                                                                                         
    Terminal Sacrifice                                38                                                                            
    Terminal Sacrifice                                              5                                                               
  Other                                                1                                                                            
  Animals Examined Microscopically                    59           15                                                               
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Esophagus                                          (58)         (10)                                                             
      Squamous Cell Carcinoma                          1 (2%)                                                                       
   Gallbladder                                        (52)         (9)                                                              
      Sarcoma, Metastatic, Mesentery                   1 (2%)                                                                       
   Intestine Large, Colon                             (53)         (9)                                                              
      Hepatocholangiocarcinoma, Metastatic, Liver      1 (2%)                                                                       
   Intestine Large, Cecum                             (52)         (9)                                                              
      Leiomyosarcoma                                   1 (2%)                                                                       
      Sarcoma, Metastatic, Mesentery                   1 (2%)                                                                       
   Intestine Small, Duodenum                          (52)         (9)                                                              
      Hepatocholangiocarcinoma, Metastatic, Liver      1 (2%)                                                                       
   Intestine Small, Ileum                             (50)         (9)                                                              
   Liver                                              (58)         (10)                                                             
      Hemangiosarcoma                                  1 (2%)                                                                       
      Hepatocellular Carcinoma                         3 (5%)       1 (10%)                                                         
      Hepatocellular Adenoma                           5 (9%)                                                                       
      Hepatocholangiocarcinoma                         1 (2%)                                                                       
      Histiocytic Sarcoma                              2 (3%)                                                                       
      Sarcoma, Metastatic, Mesentery                   1 (2%)                                                                       
   Mesentery                                          (2)          (1)                                                              
      Hepatocholangiocarcinoma, Metastatic, Liver      1 (50%)                                                                      
      Sarcoma                                          1 (50%)                                                                      
   Pancreas                                           (57)         (10)                                                             
      Hepatocholangiocarcinoma, Metastatic, Liver      1 (2%)                                                                       
      Sarcoma, Metastatic, Mesentery                   1 (2%)                                                                       
   Salivary Glands                                    (58)         (10)                                                             
   Stomach, Forestomach                               (55)         (10)                                                             
      Sarcoma, Metastatic, Mesentery                   1 (2%)                                                                       
      Squamous Cell Papilloma                                       1 (10%)                                                         
                                                             Page   8                                                               
NTP Experiment-Test: 05123-06  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                            NICKEL OXIDE                                       Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 05:20:49  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE FEMALE                        5.0MG/M3     5.0MG/M3                                                            
                                                                  LUNGTX                                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - cont                                                                                                            
   Stomach, Glandular                                 (55)         (10)                                                             
      Hepatocholangiocarcinoma, Metastatic, Liver      1 (2%)                                                                       
      Sarcoma, Metastatic, Mesentery                   1 (2%)                                                                       
   Tooth                                              (2)                                                                           
      Odontoma                                         1 (50%)                                                                      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Heart                                              (59)         (10)                                                             
      Hepatocholangiocarcinoma, Metastatic, Liver      1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (57)         (10)                                                             
      Adenoma                                          1 (2%)                                                                       
      Hepatocholangiocarcinoma, Metastatic, Liver      1 (2%)                                                                       
   Islets, Pancreatic                                 (57)         (10)                                                             
   Pituitary Gland                                    (57)         (10)                                                             
      Pars Distalis, Adenoma                           6 (11%)                                                                      
      Pars Distalis, Carcinoma                         1 (2%)                                                                       
      Pars Intermedia, Adenoma                         1 (2%)                                                                       
   Thyroid Gland                                      (59)         (10)                                                             
      Follicular Cell, Adenoma                                      1 (10%)                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   Tissue NOS                                                      (1)                                                              
      Hemangiosarcoma, Metastatic                                   1 (100%)                                                        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Ovary                                              (58)         (10)                                                             
      Sarcoma, Metastatic, Mesentery                   1 (2%)                                                                       
      Teratoma Malignant                               1 (2%)                                                                       
   Uterus                                             (58)         (11)                                                             
      Hemangiosarcoma                                  1 (2%)                                                                       
      Polyp Stromal                                    1 (2%)                                                                       
      Sarcoma, Metastatic, Mesentery                   1 (2%)                                                                       
      Teratoma Malignant, Metastatic                   1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                             Page   9                                                               
NTP Experiment-Test: 05123-06  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                            NICKEL OXIDE                                       Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 05:20:49  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE FEMALE                        5.0MG/M3     5.0MG/M3                                                            
                                                                  LUNGTX                                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (58)         (10)                                                             
      Hemangiosarcoma, Metastatic                                   1 (10%)                                                         
   Lymph Node                                         (9)                                                                           
      Pancreatic, Histiocytic Sarcoma                  1 (11%)                                                                      
      Pancreatic, Sarcoma, Metastatic, Mesentery       1 (11%)                                                                      
      Renal, Sarcoma, Metastatic, Mesentery            1 (11%)                                                                      
   Lymph Node, Bronchial                              (57)         (15)                                                             
      Histiocytic Sarcoma                              2 (4%)                                                                       
      Sarcoma, Metastatic, Mesentery                   1 (2%)                                                                       
   Lymph Node, Mandibular                             (54)         (9)                                                              
   Lymph Node, Mesenteric                             (51)         (9)                                                              
      Hemangioma                                       1 (2%)                                                                       
      Hepatocholangiocarcinoma, Metastatic, Liver      1 (2%)                                                                       
      Sarcoma, Metastatic, Mesentery                   1 (2%)                                                                       
   Lymph Node, Mediastinal                            (24)         (9)                                                              
      Hepatocholangiocarcinoma, Metastatic, Liver      1 (4%)                                                                       
      Histiocytic Sarcoma                              1 (4%)                                                                       
      Sarcoma, Metastatic, Mesentery                   1 (4%)                                                                       
   Spleen                                             (58)         (10)                                                             
      Hemangiosarcoma                                               2 (20%)                                                         
      Hepatocholangiocarcinoma, Metastatic, Liver      1 (2%)                                                                       
      Histiocytic Sarcoma                              2 (3%)                                                                       
      Sarcoma, Metastatic, Mesentery                   1 (2%)                                                                       
   Thymus                                             (52)         (9)                                                              
      Hepatocholangiocarcinoma, Metastatic, Liver      1 (2%)                                                                       
      Histiocytic Sarcoma                              1 (2%)                                                                       
      Sarcoma, Metastatic, Mesentery                   1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (58)         (10)                                                             
      Carcinoma                                        3 (5%)                                                                       
   Skin                                               (11)         (2)                                                              
      Sarcoma                                          1 (9%)                                                                       
      Squamous Cell Papilloma                          1 (9%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Skeletal Muscle                                    (3)                                                                           
      Hepatocholangiocarcinoma, Metastatic, Liver      1 (33%)                                                                      
      Sarcoma, Metastatic, Mesentery                   1 (33%)                                                                      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                             Page  10                                                               
NTP Experiment-Test: 05123-06  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                            NICKEL OXIDE                                       Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 05:20:49  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE FEMALE                        5.0MG/M3     5.0MG/M3                                                            
                                                                  LUNGTX                                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (59)         (10)                                                             
      Hypothalamus, Carcinoma, Metastatic              1 (2%)                                                                       
      Pons, Carcinoma, Metastatic                      1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Lung                                               (59)         (15)                                                             
      Alveolar/Bronchiolar Adenoma                     3 (5%)                                                                       
      Alveolar/Bronchiolar Carcinoma                   3 (5%)       2 (13%)                                                         
      Hepatocellular Carcinoma, Metastatic                          1 (7%)                                                          
      Hepatocholangiocarcinoma, Metastatic, Liver      1 (2%)                                                                       
      Histiocytic Sarcoma                              2 (3%)                                                                       
      Sarcoma, Metastatic, Mesentery                   1 (2%)                                                                       
      Teratoma Malignant, Metastatic                   1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Harderian Gland                                    (3)                                                                           
      Adenoma                                          3 (100%)                                                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (58)         (15)                                                             
      Hepatocholangiocarcinoma, Metastatic, Liver      1 (2%)                                                                       
      Teratoma Malignant, Metastatic                   1 (2%)                                                                       
   Urinary Bladder                                    (52)         (10)                                                             
      Sarcoma, Metastatic, Mesentery                   1 (2%)                                                                       
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SYSTEMIC LESIONS                                                                                                                   
   Multiple Organs                                   *(59)        *(15)                                                             
      Histiocytic Sarcoma                              2 (3%)                                                                       
      Lymphoma Malignant                               7 (12%)                                                                      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
     *   Number of animals with any tissue examined microscopically                                                                 
                                                             Page  11                                                               
NTP Experiment-Test: 05123-06  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                            NICKEL OXIDE                                       Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 05:20:49  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE FEMALE                        5.0MG/M3     5.0MG/M3                                                            
                                                                  LUNGTX                                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
TUMOR SUMMARY                                                                                                                       
                                                                                                                                    
   Total Animals with Primary Neoplasms (b)            36           4                                                               
     Total Primary Neoplasms                           50           7                                                               
                                                                                                                                    
   Total Animals with Benign Neoplasms                 22           2                                                               
     Total Benign Neoplasms                            23           2                                                               
                                                                                                                                    
   Total Animals with Malignant Neoplasms              24           4                                                               
     Total Malignant Neoplasms                         27           5                                                               
                                                                                                                                    
   Total Animals with Metastatic Neoplasms              4           2                                                               
     Total Metastatic Neoplasm                         37           3                                                               
                                                                                                                                    
   Total Animals with Malignant Neoplasms                                                                                           
   Uncertain Primary Site                                                                                                           
                                                                                                                                    
   Total Animals with Neoplasms Uncertain-                                                                                          
   Benign or Malignant                                                                                                              
     Total Uncertain Neoplasms                                                                                                      
                                                                                                                                    
____________________________________________________________________________________________________________________________________
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Primary tumors: all tumors except metastatic tumors                                                                              
                                                             Page  12                                                               
NTP Experiment-Test: 05123-06  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                            NICKEL OXIDE                                       Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 05:20:49  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE MALE                          0 MG/M3      O MG/M3      1.25MGM3     1.25MGM3     2.5MG/M3     2.5MG/M3        
                                                                  LUNGTX                    LUNGTX                    LUNGTX        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially in Study                          60           20           60           20           60           20           
  Scheduled Sacrifice                                              10                        10                        10           
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                22            1           20            6           23            3           
    Natural Death                                     14            1           17            1            8            3           
    Accidently Killed                                  4            6                                                               
  Survivors                                                                                                                         
    Terminal Sacrifice                                19                        23                        29                        
    Terminal Sacrifice                                              2                         3                         4           
  Other                                                1                                                                            
  Animals Examined Microscopically                    55           12           60           17           60           16           
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Esophagus                                          (54)         (7)          (60)         (12)         (60)         (11)         
      Squamous Cell Carcinoma                                                    1 (2%)                                             
   Intestine Small, Duodenum                          (49)         (7)          (46)         (12)         (53)         (8)          
      Adenoma                                                                                              1 (2%)                   
   Intestine Small, Ileum                             (49)         (7)          (43)         (11)         (52)         (8)          
   Liver                                              (55)         (8)          (60)         (12)         (60)         (13)         
      Hemangiosarcoma                                  1 (2%)                                                                       
      Hemangiosarcoma, Multiple                                                  1 (2%)                                             
      Hepatocellular Carcinoma                         6 (11%)      1 (13%)     11 (18%)      3 (25%)      8 (13%)      1 (8%)      
      Hepatocellular Carcinoma, Multiple                                         3 (5%)                    2 (3%)       1 (8%)      
      Hepatocellular Adenoma                           7 (13%)      2 (25%)      5 (8%)       1 (8%)      11 (18%)      4 (31%)     
      Hepatocellular Adenoma, Multiple                 1 (2%)                                              1 (2%)       1 (8%)      
   Mesentery                                          (1)                       (1)                                                 
      Lipoma                                           1 (100%)                                                                     
   Salivary Glands                                    (55)         (7)          (60)         (12)         (60)         (11)         
   Stomach, Forestomach                               (52)         (7)          (57)         (11)         (60)         (10)         
      Squamous Cell Papilloma                          1 (2%)                    1 (2%)                                             
   Tooth                                              (2)                       (5)                       (4)                       
      Odontoma                                                                   1 (20%)                   2 (50%)                  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Heart                                              (55)         (7)          (60)         (12)         (60)         (11)         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                             Page  13                                                               
NTP Experiment-Test: 05123-06  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                            NICKEL OXIDE                                       Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 05:20:49  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE MALE                          0 MG/M3      O MG/M3      1.25MGM3     1.25MGM3     2.5MG/M3     2.5MG/M3        
                                                                  LUNGTX                    LUNGTX                    LUNGTX        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (55)         (7)          (60)         (12)         (59)         (11)         
      Adenoma                                          2 (4%)                                                                       
      Capsule, Adenoma                                 2 (4%)                                              1 (2%)                   
   Islets, Pancreatic                                 (52)         (7)          (57)         (12)         (60)         (11)         
      Adenoma                                                                                              1 (2%)                   
   Thyroid Gland                                      (53)         (7)          (60)         (12)         (60)         (11)         
      Bilateral, Follicular Cell, Adenoma                                        2 (3%)                                             
      Follicular Cell, Adenoma                         2 (4%)       1 (14%)                                1 (2%)       1 (9%)      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   Tissue NOS                                         (1)          (1)                       (1)          (3)                       
      Hemangiosarcoma                                               1 (100%)                                                        
      Lipoma                                                                                               1 (33%)                  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Epididymis                                         (54)         (7)          (60)         (12)         (60)         (11)         
      Sarcoma                                          1 (2%)                                                                       
   Prostate                                           (51)         (7)          (55)         (11)         (57)         (11)         
   Testes                                             (55)         (7)          (59)         (12)         (60)         (11)         
      Interstitial Cell, Adenoma                                                                           2 (3%)                   
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (54)         (7)          (59)         (12)         (60)         (11)         
      Hemangiosarcoma, Metastatic                                   1 (14%)                                                         
   Lymph Node                                         (21)         (2)          (13)         (6)          (17)         (3)          
   Lymph Node, Bronchial                              (43)         (11)         (50)         (14)         (56)         (15)         
   Lymph Node, Mandibular                             (45)         (7)          (51)         (11)         (57)         (11)         
   Lymph Node, Mesenteric                             (43)         (7)          (48)         (12)         (52)         (9)          
   Lymph Node, Mediastinal                            (16)         (8)          (19)         (2)          (19)         (8)          
      Hemangiosarcoma, Metastatic                                                                          1 (5%)                   
   Spleen                                             (54)         (7)          (60)         (12)         (60)         (11)         
      Hemangiosarcoma                                  1 (2%)                    1 (2%)                    2 (3%)                   
   Thymus                                             (43)         (7)          (49)         (8)          (47)         (10)         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                             Page  14                                                               
NTP Experiment-Test: 05123-06  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                            NICKEL OXIDE                                       Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 05:20:49  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE MALE                          0 MG/M3      O MG/M3      1.25MGM3     1.25MGM3     2.5MG/M3     2.5MG/M3        
                                                                  LUNGTX                    LUNGTX                    LUNGTX        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Skin                                               (16)                      (18)         (5)          (22)         (2)          
      Hamartoma                                                                  1 (6%)                                             
      Subcutaneous Tissue, Hemangioma                                            1 (6%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (55)         (7)          (60)         (12)         (60)         (11)         
      Hemangiosarcoma, Metastatic                                   1 (14%)                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Lung                                               (55)         (12)         (60)         (17)         (60)         (16)         
      Alveolar/Bronchiolar Adenoma                     7 (13%)      2 (17%)      5 (8%)                    6 (10%)                  
      Alveolar/Bronchiolar Carcinoma                   4 (7%)                    8 (13%)      1 (6%)       9 (15%)                  
      Alveolar/Bronchiolar Carcinoma, Multiple                                   1 (2%)                                             
      Hepatocellular Carcinoma, Metastatic                          1 (8%)                    1 (6%)       3 (5%)                   
      Hepatocellular Carcinoma, Metastatic, Liver                                1 (2%)                                             
   Nose                                               (53)         (12)         (59)         (17)         (60)         (16)         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Harderian Gland                                                              (1)                       (2)                       
      Adenoma                                                                    1 (100%)                  2 (100%)                 
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (55)         (12)         (60)         (17)         (60)         (16)         
   Urinary Bladder                                    (52)         (7)          (56)         (12)         (59)         (10)         
      Transitional Epithelium, Papilloma                                         1 (2%)                                             
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SYSTEMIC LESIONS                                                                                                                   
   Multiple Organs                                   *(55)        *(12)        *(60)        *(17)        *(60)        *(16)         
      Lymphoma Malignant                               2 (4%)                    1 (2%)       1 (6%)       2 (3%)                   
____________________________________________________________________________________________________________________________________
                                                                                                                                    
     *   Number of animals with any tissue examined microscopically                                                                 
                                                             Page  15                                                               
NTP Experiment-Test: 05123-06  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                            NICKEL OXIDE                                       Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 05:20:49  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE MALE                          0 MG/M3      O MG/M3      1.25MGM3     1.25MGM3     2.5MG/M3     2.5MG/M3        
                                                                  LUNGTX                    LUNGTX                    LUNGTX        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
TUMOR SUMMARY                                                                                                                       
                                                                                                                                    
   Total Animals with Primary Neoplasms (b)            28           6          33           6          38           7               
     Total Primary Neoplasms                           38           7          45           6          52           8               
                                                                                                                                    
   Total Animals with Benign Neoplasms                 18           4          16           1          23           6               
     Total Benign Neoplasms                            23           5          18           1          29           6               
                                                                                                                                    
   Total Animals with Malignant Neoplasms              14           2          24           5          21           2               
     Total Malignant Neoplasms                         15           2          27           5          23           2               
                                                                                                                                    
   Total Animals with Metastatic Neoplasms                          2           1           1           4                           
     Total Metastatic Neoplasm                                      3           1           1           4                           
                                                                                                                                    
   Total Animals with Malignant Neoplasms                                                                                           
   Uncertain Primary Site                                                                                                           
                                                                                                                                    
   Total Animals with Neoplasms Uncertain-                                                                                          
   Benign or Malignant                                                                                                              
     Total Uncertain Neoplasms                                                                                                      
                                                                                                                                    
____________________________________________________________________________________________________________________________________
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Primary tumors: all tumors except metastatic tumors                                                                              
                                                             Page  16                                                               
NTP Experiment-Test: 05123-06  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                            NICKEL OXIDE                                       Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 05:20:49  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE MALE                          5.0MG/M3     5.0MG/M3                                                            
                                                                  LUNGTX                                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially in Study                          60           20                                                               
  Scheduled Sacrifice                                              10                                                               
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                22            7                                                               
    Natural Death                                     15            2                                                               
  Survivors                                                                                                                         
    Terminal Sacrifice                                23                                                                            
    Terminal Sacrifice                                              1                                                               
  Animals Examined Microscopically                    60           19                                                               
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Intestine Large, Colon                             (53)         (14)                                                             
   Intestine Large, Cecum                             (52)         (13)                                                             
   Intestine Small, Ileum                             (49)         (13)                                                             
   Liver                                              (60)         (14)                                                             
      Alveolar/Bronchiolar Carcinoma, Metastatic,                                                                                   
           Lung                                        1 (2%)                                                                       
      Hemangiosarcoma                                  2 (3%)                                                                       
      Hepatocellular Carcinoma                        13 (22%)                                                                      
      Hepatocellular Carcinoma, Multiple               2 (3%)                                                                       
      Hepatocellular Adenoma                           8 (13%)      1 (7%)                                                          
      Hepatocholangiocarcinoma                         1 (2%)                                                                       
      Histiocytic Sarcoma                              1 (2%)                                                                       
   Stomach, Forestomach                               (58)         (14)                                                             
      Squamous Cell Papilloma                          1 (2%)                                                                       
   Tooth                                              (1)                                                                           
      Odontoma                                         1 (100%)                                                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Heart                                              (60)         (14)                                                             
      Alveolar/Bronchiolar Carcinoma, Metastatic,                                                                                   
           Lung                                        1 (2%)                                                                       
      Hepatocholangiocarcinoma, Metastatic, Liver      1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                             Page  17                                                               
NTP Experiment-Test: 05123-06  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                            NICKEL OXIDE                                       Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 05:20:49  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE MALE                          5.0MG/M3     5.0MG/M3                                                            
                                                                  LUNGTX                                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (60)         (14)                                                             
      Adenoma                                          1 (2%)                                                                       
   Thyroid Gland                                      (60)         (14)                                                             
      Follicular Cell, Adenoma                         2 (3%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   Tissue NOS                                         (2)          (2)                                                              
      Alveolar/Bronchiolar Carcinoma, Metastatic,                                                                                   
           Lung                                        1 (50%)                                                                      
      Hepatocholangiocarcinoma, Metastatic, Liver      1 (50%)                                                                      
      Sarcoma                                                       1 (50%)                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Lymph Node                                         (12)         (4)                                                              
      Axillary, Alveolar/Bronchiolar Carcinoma,                                                                                     
           Metastatic, Lung                            1 (8%)                                                                       
   Lymph Node, Bronchial                              (55)         (16)                                                             
      Hepatocholangiocarcinoma, Metastatic, Liver      1 (2%)                                                                       
   Lymph Node, Mandibular                             (52)         (13)                                                             
   Lymph Node, Mesenteric                             (54)         (14)                                                             
      Hepatocholangiocarcinoma, Metastatic, Liver      1 (2%)                                                                       
   Lymph Node, Mediastinal                            (20)         (9)                                                              
   Spleen                                             (60)         (14)                                                             
      Hemangioma                                       1 (2%)                                                                       
      Hemangiosarcoma                                  1 (2%)                                                                       
      Histiocytic Sarcoma                              1 (2%)                                                                       
   Thymus                                             (51)         (12)                                                             
      Alveolar/Bronchiolar Carcinoma, Metastatic,                                                                                   
           Lung                                        1 (2%)                                                                       
      Hepatocholangiocarcinoma, Metastatic, Liver      1 (2%)                                                                       
      Histiocytic Sarcoma                              1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                             Page  18                                                               
NTP Experiment-Test: 05123-06  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                            NICKEL OXIDE                                       Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 05:20:49  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE MALE                          5.0MG/M3     5.0MG/M3                                                            
                                                                  LUNGTX                                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Lung                                               (60)         (19)                                                             
      Alveolar/Bronchiolar Adenoma                     9 (15%)      2 (11%)                                                         
      Alveolar/Bronchiolar Carcinoma                   4 (7%)       1 (5%)                                                          
      Alveolar/Bronchiolar Carcinoma, Multiple         1 (2%)                                                                       
      Hepatocellular Carcinoma, Metastatic             4 (7%)                                                                       
      Hepatocholangiocarcinoma, Metastatic, Liver      1 (2%)                                                                       
      Histiocytic Sarcoma                              1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Harderian Gland                                    (3)                                                                           
      Adenoma                                          2 (67%)                                                                      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (59)         (19)                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SYSTEMIC LESIONS                                                                                                                   
   Multiple Organs                                   *(60)        *(19)                                                             
      Histiocytic Sarcoma                              1 (2%)                                                                       
      Lymphoma Malignant                               4 (7%)       1 (5%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
     *   Number of animals with any tissue examined microscopically                                                                 
                                                             Page  19                                                               
NTP Experiment-Test: 05123-06  INCIDENCE RATES OF NEOPLASMS BY ANATOMIC SITE (SYSTEMIC LESIONS ABRIDGED) (a)      Report: PEIRPT05
Study Type: CHRONIC                                            NICKEL OXIDE                                       Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 05:20:49  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE MALE                          5.0MG/M3     5.0MG/M3                                                            
                                                                  LUNGTX                                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
TUMOR SUMMARY                                                                                                                       
                                                                                                                                    
   Total Animals with Primary Neoplasms (b)            39           5                                                               
     Total Primary Neoplasms                           54           6                                                               
                                                                                                                                    
   Total Animals with Benign Neoplasms                 23           3                                                               
     Total Benign Neoplasms                            25           3                                                               
                                                                                                                                    
   Total Animals with Malignant Neoplasms              27           3                                                               
     Total Malignant Neoplasms                         29           3                                                               
                                                                                                                                    
   Total Animals with Metastatic Neoplasms              6                                                                           
     Total Metastatic Neoplasm                         15                                                                           
                                                                                                                                    
   Total Animals with Malignant Neoplasms                                                                                           
   Uncertain Primary Site                                                                                                           
                                                                                                                                    
   Total Animals with Neoplasms Uncertain-                                                                                          
   Benign or Malignant                                                                                                              
     Total Uncertain Neoplasms                                                                                                      
                                                                                                                                    
____________________________________________________________________________________________________________________________________
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Primary tumors: all tumors except metastatic tumors                                                                              
                                                             Page  20                                                               
                             ------------------------------------------------------------                                           
                             ----------              END OF REPORT             ----------                                           
                             ------------------------------------------------------------