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https://ntp.niehs.nih.gov/go/3340

TDMS Study 05122-06 Pathology Tables


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


NTP Experiment-Test: 05122-06                                                                                     Report: PEIRPT03
Study Type: CHRONIC                                                                                               Date: 05/20/95
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 03:47:06




       Facility:  Lovelace Inhalation Toxicology Research Institute

       Chemical CAS #:  010101970

       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: 05122-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                     NICKEL SULFATE HEXAHYDRATE                                Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 03:47:06  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        0.0          0.0MG/M3     0.25         .25MG/M3     0.5          0.5MG/M3        
                                                   MG/M3        LUNG TOX     MG/M3        LUNG TOX     MG/M3        LUNG TOX        
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially In Study                          60           20           60           20           60           20           
  Scheduled Sacrifice                                              19                        20                        20           
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                19            1           11                        11                        
    Natural Death                                      7                        10                         4                        
  Survivors                                                                                                                         
    Moribund Sacrifice                                 1                         1                                                  
    Terminal Sacrifice                                33                        38                        45                        
  Animals Examined Microscopically                    60           11           60           10           60           10           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Gallbladder                                        (59)         (6)          (55)         (5)          (57)         (5)          
      Concretion                                                                 1 (2%)                                             
      Dilatation                                       1 (2%)                                                                       
   Intestine Large, Rectum                            (56)         (4)          (57)         (4)          (55)         (4)          
      Autolysis                                                                  1 (2%)                                             
   Intestine Large, Cecum                             (60)         (6)          (57)         (5)          (60)         (5)          
      Autolysis                                                                  1 (2%)                                             
   Intestine Small, Duodenum                          (57)         (6)          (57)         (5)          (59)         (5)          
      Autolysis                                                                  1 (2%)                                             
      Inflammation                                                                                         1 (2%)                   
      Intussusception                                  1 (2%)                                                                       
   Intestine Small, Jejunum                           (60)         (6)          (58)         (5)          (59)         (5)          
      Autolysis                                                                  1 (2%)                                             
      Peyer's Patch, Hyperplasia, Lymphoid                                       1 (2%)                    1 (2%)                   
   Intestine Small, Ileum                             (60)         (6)          (58)         (5)          (58)         (5)          
      Autolysis                                                                  1 (2%)                                             
   Liver                                              (60)         (6)          (59)         (5)          (60)         (5)          
      Autolysis                                                                  1 (2%)                                             
      Basophilic Focus                                 2 (3%)                                              2 (3%)                   
      Congestion                                       1 (2%)                                                                       
      Fatty Change                                     1 (2%)                                                                       
      Hematopoietic Cell Proliferation                                           1 (2%)                                             
      Hemorrhage                                       1 (2%)                                                                       
      Hepatodiaphragmatic Nodule                                                 1 (2%)                                             
      Infarct                                          2 (3%)                                              1 (2%)                   
      Inflammation                                     1 (2%)                    1 (2%)                                             
      Necrosis                                         2 (3%)                    1 (2%)                    2 (3%)                   
      Necrosis, Diffuse                                4 (7%)                    4 (7%)                    1 (2%)                   
   Mesentery                                          (7)                       (4)                       (4)                       
      Inflammation                                     1 (14%)                   1 (25%)                                            
      Inflammation, Chronic                                                                                1 (25%)                  
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    2                                                              
NTP Experiment-Test: 05122-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                     NICKEL SULFATE HEXAHYDRATE                                Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 03:47:06  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        0.0          0.0MG/M3     0.25         .25MG/M3     0.5          0.5MG/M3        
                                                   MG/M3        LUNG TOX     MG/M3        LUNG TOX     MG/M3        LUNG TOX        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
   Pancreas                                           (59)         (6)          (58)         (5)          (60)         (5)          
      Amyloid Deposition                                                         1 (2%)                                             
      Infiltration Cellular, Lymphocyte                                                                    1 (2%)                   
      Inflammation                                                                                         1 (2%)                   
      Acinus, Hyperplasia, Focal                       1 (2%)                                                                       
      Duct, Cyst, Multiple                                                                                 1 (2%)                   
   Salivary Glands                                    (60)         (6)          (59)         (5)          (60)         (5)          
      Angiectasis                                      1 (2%)                                                                       
   Stomach, Forestomach                               (60)         (6)          (58)         (5)          (60)         (5)          
      Hyperplasia, Squamous                                                      1 (2%)                    2 (3%)                   
      Inflammation                                     1 (2%)                    2 (3%)                                             
   Stomach, Glandular                                 (59)         (6)          (58)         (5)          (59)         (5)          
      Hyperplasia                                                                                          1 (2%)                   
   Tooth                                                                        (2)                       (1)                       
      Peridontal Tissue, Inflammation                                            2 (100%)                  1 (100%)                 
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Heart                                              (60)         (6)          (59)         (5)          (60)         (5)          
      Cardiomyopathy                                   1 (2%)                                                                       
      Infiltration Cellular, Lymphocyte                                          1 (2%)                                             
      Inflammation                                                               1 (2%)                    2 (3%)                   
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (59)         (6)          (58)         (5)          (60)         (5)          
      Cyst                                             1 (2%)                                                                       
      Capsule, Hyperplasia                                                       1 (2%)                                             
      Extra Adrenal Tissue, Inflammation               1 (2%)                                                                       
   Adrenal Medulla                                    (59)         (6)          (57)         (5)          (60)         (5)          
      Mineralization                                   1 (2%)                                                                       
   Parathyroid Gland                                  (40)         (4)          (44)         (3)          (50)         (5)          
      Cyst                                                                                    1 (33%)      1 (2%)                   
      Bilateral, Hyperplasia                           1 (3%)                                                                       
   Pituitary Gland                                    (58)         (6)          (56)         (5)          (59)         (5)          
      Angiectasis                                      1 (2%)                                              1 (2%)                   
      Cyst                                                                                                 1 (2%)                   
      Pars Distalis, Angiectasis                       3 (5%)                    2 (4%)                    8 (14%)                  
      Pars Distalis, Hyperplasia                      12 (21%)                   8 (14%)                  15 (25%)                  
      Pars Distalis, Hyperplasia, Focal                                                                                 1 (20%)     
   Thyroid Gland                                      (59)         (6)          (59)         (5)          (60)         (5)          
      Cyst                                                          1 (17%)                                                         
      Follicular Cell, Hyperplasia, Cystic            22 (37%)                  20 (34%)                  27 (45%)                  
      Follicular Cell, Hyperplasia, Focal                                                     1 (20%)                               
____________________________________________________________________________________________________________________________________
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    3                                                              
NTP Experiment-Test: 05122-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                     NICKEL SULFATE HEXAHYDRATE                                Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 03:47:06  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        0.0          0.0MG/M3     0.25         .25MG/M3     0.5          0.5MG/M3        
                                                   MG/M3        LUNG TOX     MG/M3        LUNG TOX     MG/M3        LUNG TOX        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   Tissue NOS                                         (5)                       (8)                       (4)                       
      Thrombosis                                       1 (20%)                                                                      
      Abdominal, Cyst                                                                                      1 (25%)                  
      Abdominal, Inflammation                                                    1 (13%)                                            
      Mediastinum, Infiltration Cellular,                                                                                           
          Lymphocyte                                                             1 (13%)                                            
      Mediastinum, Inflammation                        1 (20%)                   1 (13%)                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Clitoral Gland                                     (57)         (6)          (56)         (5)          (52)         (5)          
      Atrophy                                                                                              1 (2%)                   
      Ectasia                                          4 (7%)                    4 (7%)                    5 (10%)                  
      Hyperplasia, Squamous                                                      1 (2%)                                             
      Inflammation                                     2 (4%)       1 (17%)      4 (7%)                    3 (6%)                   
      Pigmentation                                     3 (5%)                                              2 (4%)                   
   Ovary                                              (58)         (6)          (58)         (5)          (60)         (5)          
      Atrophy                                          1 (2%)                                                                       
      Cyst                                             6 (10%)                   8 (14%)                  17 (28%)      1 (20%)     
      Hemorrhage                                                                 1 (2%)                                             
      Inflammation                                     1 (2%)                                                                       
      Bilateral, Cyst                                                            1 (2%)                    1 (2%)                   
      Periovarian Tissue, Cyst                                                                                          1 (20%)     
   Uterus                                             (60)         (7)          (60)         (7)          (60)         (6)          
      Congestion                                       1 (2%)                                                                       
      Dilatation                                                                                           1 (2%)                   
      Hemorrhage                                       1 (2%)                                                                       
      Infiltration Cellular, Lymphocyte                                          1 (2%)                                             
      Inflammation                                                               1 (2%)                                             
      Thrombosis                                                                 1 (2%)                                             
      Endometrium, Hyperplasia                        30 (50%)      5 (71%)     25 (42%)      6 (86%)     39 (65%)      5 (83%)     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (60)         (6)          (59)         (5)          (60)         (5)          
      Hyperplasia, Histiocytic                         1 (2%)                                              1 (2%)                   
      Hyperplasia, Megakaryocyte                       1 (2%)                                                                       
      Hyperplasia, Plasma Cell                         1 (2%)                                                                       
      Myelofibrosis                                   39 (65%)                  43 (73%)                  52 (87%)                  
      Erythroid Cell, Hyperplasia                      1 (2%)                                                                       
      Myeloid Cell, Hyperplasia                        6 (10%)                   4 (7%)                    2 (3%)                   
   Lymph Node                                         (11)                      (11)                      (13)                      
      Iliac, Hyperplasia, Lymphoid                     1 (9%)                    3 (27%)                   1 (8%)                   
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    4                                                              
NTP Experiment-Test: 05122-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                     NICKEL SULFATE HEXAHYDRATE                                Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 03:47:06  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        0.0          0.0MG/M3     0.25         .25MG/M3     0.5          0.5MG/M3        
                                                   MG/M3        LUNG TOX     MG/M3        LUNG TOX     MG/M3        LUNG TOX        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
HEMATOPOIETIC SYSTEM - CONT                                                                                                         
      Iliac, Hyperplasia, Plasma Cell                  1 (9%)                                                                       
      Inguinal, Hyperplasia, Lymphoid                  2 (18%)                                             2 (15%)                  
      Pancreatic, Hyperplasia, Lymphoid                                          1 (9%)                    1 (8%)                   
      Pancreatic, Inflammation                         1 (9%)                                                                       
      Renal, Hyperplasia, Lymphoid                     1 (9%)                    2 (18%)                                            
      Renal, Hyperplasia, Plasma Cell                  1 (9%)                                                                       
   Lymph Node, Bronchial                              (50)         (7)          (54)         (9)          (58)         (9)          
      Amyloid Deposition                                                         1 (2%)                                             
      Congestion                                       1 (2%)                    1 (2%)                                             
      Edema                                            1 (2%)                                                                       
      Hyperplasia, Lymphoid                           15 (30%)      2 (29%)      9 (17%)      3 (33%)     16 (28%)      3 (33%)     
      Hyperplasia, Macrophage                          2 (4%)                                             14 (24%)                  
      Hyperplasia, Plasma Cell                         2 (4%)                                                                       
      Inflammation                                     1 (2%)                                                                       
   Lymph Node, Mandibular                             (55)         (9)          (56)         (7)          (60)         (6)          
      Congestion                                       1 (2%)                                                                       
      Cyst                                             1 (2%)                                              1 (2%)                   
      Hyperplasia, Histiocytic                                                   2 (4%)                                             
      Hyperplasia, Lymphoid                           15 (27%)      6 (67%)      6 (11%)      2 (29%)      5 (8%)       2 (33%)     
      Hyperplasia, Mast Cell                                                                               1 (2%)                   
      Hyperplasia, Plasma Cell                         5 (9%)                    5 (9%)                    5 (8%)                   
   Lymph Node, Mesenteric                             (56)         (6)          (52)         (3)          (56)         (5)          
      Congestion                                       4 (7%)                    3 (6%)                    1 (2%)                   
      Edema                                            1 (2%)                                                                       
      Hematopoietic Cell Proliferation                 1 (2%)                                                                       
      Hyperplasia, Histiocytic                                                   1 (2%)                                             
      Hyperplasia, Lymphoid                            1 (2%)                    1 (2%)                    4 (7%)                   
      Hyperplasia, Plasma Cell                         1 (2%)                                                                       
      Inflammation                                     1 (2%)                                                                       
   Lymph Node, Mediastinal                            (30)         (2)          (28)         (5)          (33)         (1)          
      Hyperplasia, Histiocytic                                                                             2 (6%)                   
      Hyperplasia, Lymphoid                            3 (10%)                                             1 (3%)                   
      Hyperplasia, Plasma Cell                                                   1 (4%)                                             
      Inflammation                                     1 (3%)                    1 (4%)                                             
   Spleen                                             (60)         (6)          (58)         (5)          (60)         (5)          
      Angiectasis                                                                                          1 (2%)                   
      Congestion                                       3 (5%)                    1 (2%)                    1 (2%)                   
      Hematopoietic Cell Proliferation                11 (18%)                   9 (16%)                   8 (13%)                  
      Hyperplasia, Lymphoid                           10 (17%)                   4 (7%)                    9 (15%)      1 (20%)     
      Necrosis                                         1 (2%)                                                                       
   Thymus                                             (57)         (6)          (54)         (3)          (54)         (5)          
      Atrophy                                         14 (25%)      1 (17%)     11 (20%)                   8 (15%)                  
      Cyst                                                          1 (17%)                                             1 (20%)     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    5                                                              
NTP Experiment-Test: 05122-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                     NICKEL SULFATE HEXAHYDRATE                                Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 03:47:06  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        0.0          0.0MG/M3     0.25         .25MG/M3     0.5          0.5MG/M3        
                                                   MG/M3        LUNG TOX     MG/M3        LUNG TOX     MG/M3        LUNG TOX        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (60)         (6)          (58)         (5)          (60)         (5)          
      Ectasia                                          1 (2%)                    2 (3%)                                             
      Hyperplasia                                                                1 (2%)                                             
   Skin                                               (60)         (6)          (59)         (5)          (59)         (5)          
      Inflammation                                     1 (2%)       1 (17%)      1 (2%)                    1 (2%)                   
      Ulcer                                                         1 (17%)                                                         
      Dermis, Fibrosis                                                           1 (2%)                    1 (2%)                   
      Dermis, Inflammation, Granulomatous                                                                  1 (2%)                   
      Hindlimb, Hemorrhage                             1 (2%)                                                                       
      Neck, Inflammation                                                                                   1 (2%)                   
      Pinna, Inflammation                              1 (2%)                                              1 (2%)                   
      Subcutaneous Tissue, Edema                       1 (2%)                                                                       
      Subcutaneous Tissue, Inflammation                                                       1 (20%)                               
      Tail, Inflammation                               1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (60)         (6)          (60)         (5)          (60)         (5)          
      Femur, Hyperostosis                              1 (2%)                    1 (2%)                                             
      Fibula, Fracture                                                                                     1 (2%)                   
      Periosteum, Femur, Inflammation                  1 (2%)                                                                       
      Tibia, Fracture                                  1 (2%)                                                                       
   Skeletal Muscle                                    (4)                       (3)                       (3)                       
      Inflammation                                     1 (25%)                   1 (33%)                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (60)         (6)          (59)         (5)          (59)         (5)          
      Compression                                      2 (3%)                    5 (8%)                    3 (5%)                   
      Cerebrum, Degeneration                                                                               3 (5%)                   
      Meninges, Inflammation                           1 (2%)                                                                       
      Pons, Degeneration                                                         1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Larynx                                             (58)         (4)          (56)         (4)          (58)         (2)          
      Hyperplasia                                                                                          2 (3%)                   
      Inflammation                                     1 (2%)                    1 (2%)       1 (25%)      1 (2%)                   
   Lung                                               (60)         (11)         (60)         (10)         (60)         (10)         
      Congestion                                       1 (2%)                                              1 (2%)                   
      Emphysema                                                                  1 (2%)                                             
      Hemorrhage                                       4 (7%)                    1 (2%)                    3 (5%)                   
      Hyperplasia, Macrophage                          7 (12%)                  24 (40%)      1 (10%)     53 (88%)      3 (30%)     
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    6                                                              
NTP Experiment-Test: 05122-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                     NICKEL SULFATE HEXAHYDRATE                                Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 03:47:06  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        0.0          0.0MG/M3     0.25         .25MG/M3     0.5          0.5MG/M3        
                                                   MG/M3        LUNG TOX     MG/M3        LUNG TOX     MG/M3        LUNG TOX        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
RESPIRATORY SYSTEM - CONT                                                                                                           
      Inflammation                                                               1 (2%)                                             
      Inflammation, Chronic Active                     1 (2%)                    7 (12%)                  14 (23%)                  
      Mineralization                                                             1 (2%)                                             
      Alveolar Epithelium, Hyperplasia                                           9 (15%)                  32 (53%)      1 (10%)     
      Alveolar Epithelium, Hyperplasia, Focal                                    1 (2%)       1 (10%)      1 (2%)                   
      Alveolus, Proteinosis                                                                               11 (18%)                  
      Interstitium, Infiltration Cellular                           1 (9%)       4 (7%)                   16 (27%)                  
      Pleura, Inflammation                             1 (2%)                                                                       
   Nose                                               (60)         (11)         (59)         (10)         (60)         (10)         
      Hemorrhage                                                    1 (9%)                                                          
      Inflammation, Acute                                           4 (36%)                   4 (40%)                   1 (10%)     
      Olfactory Epithelium, Atrophy                    3 (5%)                    2 (3%)                    1 (2%)                   
      Olfactory Epithelium, Degeneration              12 (20%)      1 (9%)       8 (14%)                   1 (2%)       1 (10%)     
      Olfactory Epithelium, Inflammation                                         1 (2%)                                             
      Olfactory Epithelium, Respiratory Epithelium,                                                                                 
           Degeneration                                             1 (9%)                                              1 (10%)     
      Respiratory Epithelium, Degeneration            11 (18%)      1 (9%)      14 (24%)      2 (20%)      4 (7%)       2 (20%)     
      Respiratory Epithelium, Inflammation             5 (8%)                    7 (12%)                  11 (18%)                  
      Respiratory Epithelium, Metaplasia, Squamous     1 (2%)                                              3 (5%)                   
      Squamous Epithelium, Inflammation                                                                    1 (2%)                   
      Vomeronasal Organ, Infiltration Cellular,                                                                                     
           Polymorphonuclear                                        1 (9%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Ear                                                                          (1)                       (2)                       
      Hemorrhage                                                                 1 (100%)                                           
      External Ear, Inflammation                                                                           2 (100%)                 
   Lacrimal Gland                                                                                         (1)                       
      Extraorbital, Hyperplasia, Plasma Cell                                                               1 (100%)                 
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (60)         (11)         (60)         (10)         (60)         (10)         
      Inflammation                                                               1 (2%)                    1 (2%)                   
      Metaplasia, Osseous                              1 (2%)                                              1 (2%)                   
      Mineralization                                                             2 (3%)                                             
      Nephropathy                                      3 (5%)                    1 (2%)                    1 (2%)                   
      Glomerulus, Inflammation                                                   1 (2%)                                             
      Medulla, Cyst                                    1 (2%)                                                                       
      Perirenal Tissue, Inflammation                   1 (2%)                                                                       
      Renal Tubule, Necrosis, Acute                                              1 (2%)                                             
   Urinary Bladder                                    (59)         (5)          (60)         (5)          (58)         (5)          
      Angiectasis                                      1 (2%)                                                                       
      Autolysis                                                                  1 (2%)                                             
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    7                                                              
NTP Experiment-Test: 05122-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                     NICKEL SULFATE HEXAHYDRATE                                Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 03:47:06  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        0.0          0.0MG/M3     0.25         .25MG/M3     0.5          0.5MG/M3        
                                                   MG/M3        LUNG TOX     MG/M3        LUNG TOX     MG/M3        LUNG TOX        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
URINARY SYSTEM - CONT                                                                                                               
      Calculus Micro Observation Only                                            1 (2%)                                             
      Hemorrhage                                                                 1 (2%)                                             
      Infiltration Cellular, Lymphocyte                                          1 (2%)                                             
      Inflammation                                     1 (2%)                                                                       
      Transitional Epithelium, Hyperplasia             1 (2%)                    1 (2%)                    1 (2%)                   
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    8                                                              
NTP Experiment-Test: 05122-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                     NICKEL SULFATE HEXAHYDRATE                                Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 03:47:06  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        1.0          1.0MG/M3                                                            
                                                   MG/M3        LUNG TOX                                                            
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially In Study                          60           20                                                               
  Scheduled Sacrifice                                              20                                                               
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                17                                                                            
    Natural Death                                      6                                                                            
  Survivors                                                                                                                         
    Terminal Sacrifice                                37                                                                            
  Animals Examined Microscopically                    60           10                                                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Liver                                              (60)         (5)                                                              
      Eosinophilic Focus                               1 (2%)                                                                       
      Hematopoietic Cell Proliferation                 1 (2%)                                                                       
      Infarct                                          1 (2%)                                                                       
      Necrosis                                         2 (3%)                                                                       
      Necrosis, Diffuse                                6 (10%)                                                                      
      Bile Duct, Degeneration                          1 (2%)                                                                       
   Mesentery                                          (5)                                                                           
      Infiltration Cellular, Lymphocyte                1 (20%)                                                                      
      Inflammation                                     1 (20%)                                                                      
      Necrosis                                         1 (20%)                                                                      
   Pancreas                                           (60)         (5)                                                              
      Inflammation                                     1 (2%)                                                                       
      Duct, Ectasia                                    1 (2%)                                                                       
   Stomach, Forestomach                               (60)         (6)                                                              
      Diverticulum                                                  1 (17%)                                                         
   Tooth                                              (1)                                                                           
      Peridontal Tissue, Inflammation                  1 (100%)                                                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Heart                                              (60)         (5)                                                              
      Inflammation                                     1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (60)         (5)                                                              
      Cyst                                             1 (2%)                                                                       
      Hyperplasia                                      1 (2%)                                                                       
      Hypertrophy                                      1 (2%)                                                                       
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    9                                                              
NTP Experiment-Test: 05122-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                     NICKEL SULFATE HEXAHYDRATE                                Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 03:47:06  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        1.0          1.0MG/M3                                                            
                                                   MG/M3        LUNG TOX                                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ENDOCRINE SYSTEM - CONT                                                                                                             
      Extra Adrenal Tissue, Inflammation               1 (2%)                                                                       
   Adrenal Medulla                                    (60)         (5)                                                              
      Hyperplasia                                      1 (2%)                                                                       
   Parathyroid Gland                                  (49)         (3)                                                              
      Hyperplasia                                      1 (2%)                                                                       
   Pituitary Gland                                    (57)         (4)                                                              
      Congestion                                       1 (2%)                                                                       
      Pars Distalis, Angiectasis                       1 (2%)                                                                       
      Pars Distalis, Hyperplasia                      11 (19%)                                                                      
      Pars Distalis, Hyperplasia, Focal                             2 (50%)                                                         
   Thyroid Gland                                      (60)         (5)                                                              
      Inflammation                                     2 (3%)                                                                       
      Follicular Cell, Hyperplasia, Cystic            27 (45%)                                                                      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   Tissue NOS                                         (3)                                                                           
      Abdominal, Inflammation                          1 (33%)                                                                      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Clitoral Gland                                     (58)         (5)                                                              
      Ectasia                                          2 (3%)       1 (20%)                                                         
      Inflammation                                     1 (2%)                                                                       
   Ovary                                              (59)         (5)                                                              
      Angiectasis                                      1 (2%)                                                                       
      Atrophy                                          1 (2%)                                                                       
      Cyst                                             8 (14%)      1 (20%)                                                         
      Hemorrhage                                       2 (3%)                                                                       
      Inflammation                                     1 (2%)                                                                       
      Pigmentation, Hemosiderin                        1 (2%)                                                                       
   Uterus                                             (60)         (6)                                                              
      Hemorrhage                                       1 (2%)                                                                       
      Inflammation                                     1 (2%)                                                                       
      Prolapse                                         1 (2%)                                                                       
      Endometrium, Hyperplasia                        41 (68%)      5 (83%)                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (60)         (5)                                                              
      Hyperplasia, Histiocytic                         1 (2%)                                                                       
      Myelofibrosis                                   41 (68%)                                                                      
      Myeloid Cell, Hyperplasia                        3 (5%)                                                                       
   Lymph Node                                         (13)                                                                          
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   10                                                              
NTP Experiment-Test: 05122-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                     NICKEL SULFATE HEXAHYDRATE                                Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 03:47:06  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        1.0          1.0MG/M3                                                            
                                                   MG/M3        LUNG TOX                                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
HEMATOPOIETIC SYSTEM - CONT                                                                                                         
      Iliac, Hyperplasia, Lymphoid                     1 (8%)                                                                       
      Iliac, Hyperplasia, Plasma Cell                  2 (15%)                                                                      
      Inguinal, Hyperplasia, Histiocytic               1 (8%)                                                                       
      Inguinal, Hyperplasia, Lymphoid                  1 (8%)                                                                       
      Inguinal, Pigmentation                           1 (8%)                                                                       
      Pancreatic, Hematopoietic Cell Proliferation     1 (8%)                                                                       
      Pancreatic, Inflammation                         1 (8%)                                                                       
      Renal, Fibrosis                                  1 (8%)                                                                       
      Renal, Hyperplasia, Histiocytic                  1 (8%)                                                                       
      Renal, Hyperplasia, Lymphoid                     2 (15%)                                                                      
   Lymph Node, Bronchial                              (56)         (8)                                                              
      Hemorrhage                                       1 (2%)                                                                       
      Hyperplasia, Histiocytic                         1 (2%)                                                                       
      Hyperplasia, Lymphoid                           26 (46%)      7 (88%)                                                         
      Hyperplasia, Macrophage                         37 (66%)      4 (50%)                                                         
   Lymph Node, Mandibular                             (55)         (6)                                                              
      Cyst                                             1 (2%)                                                                       
      Hyperplasia, Histiocytic                         1 (2%)                                                                       
      Hyperplasia, Lymphoid                            5 (9%)       1 (17%)                                                         
      Hyperplasia, Plasma Cell                         4 (7%)       1 (17%)                                                         
      Inflammation                                     1 (2%)                                                                       
   Lymph Node, Mesenteric                             (51)         (4)                                                              
      Hemorrhage                                       1 (2%)                                                                       
      Hyperplasia, Lymphoid                            2 (4%)                                                                       
      Inflammation                                     2 (4%)                                                                       
   Lymph Node, Mediastinal                            (22)         (2)                                                              
      Hyperplasia, Lymphoid                            3 (14%)                                                                      
   Spleen                                             (60)         (5)                                                              
      Hematopoietic Cell Proliferation                 9 (15%)                                                                      
      Hyperplasia, Lymphoid                           10 (17%)                                                                      
      Hyperplasia, Plasma Cell                         1 (2%)                                                                       
   Thymus                                             (56)         (5)                                                              
      Atrophy                                         12 (21%)                                                                      
      Autolysis                                        1 (2%)                                                                       
      Hyperplasia, Lymphoid                            1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (60)         (5)                                                              
      Hyperplasia                                      1 (2%)                                                                       
   Skin                                               (60)         (5)                                                              
      Inflammation                                     3 (5%)                                                                       
      Pinna, Inflammation                              1 (2%)                                                                       
      Subcutaneous Tissue, Edema                       1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   11                                                              
NTP Experiment-Test: 05122-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                     NICKEL SULFATE HEXAHYDRATE                                Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 03:47:06  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        1.0          1.0MG/M3                                                            
                                                   MG/M3        LUNG TOX                                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (60)         (5)                                                              
      Compression                                      2 (3%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Larynx                                             (56)         (4)                                                              
      Degeneration                                     1 (2%)                                                                       
      Hyperplasia                                      1 (2%)                                                                       
      Inflammation                                     2 (4%)                                                                       
   Lung                                               (60)         (10)                                                             
      Congestion                                       1 (2%)                                                                       
      Hyperplasia, Macrophage                         59 (98%)     10 (100%)                                                        
      Inflammation, Chronic Active                    40 (67%)      7 (70%)                                                         
      Alveolar Epithelium, Hyperplasia                45 (75%)      5 (50%)                                                         
      Alveolar Epithelium, Metaplasia, Squamous        1 (2%)                                                                       
      Alveolus, Proteinosis                           45 (75%)      5 (50%)                                                         
      Bronchiole, Degeneration                         2 (3%)                                                                       
      Interstitium, Infiltration Cellular             39 (65%)      6 (60%)                                                         
   Nose                                               (60)         (10)                                                             
      Inflammation, Acute                                           5 (50%)                                                         
      Olfactory Epithelium, Atrophy                   17 (28%)      1 (10%)                                                         
      Olfactory Epithelium, Degeneration               8 (13%)                                                                      
      Olfactory Epithelium, Inflammation               2 (3%)                                                                       
      Respiratory Epithelium, Degeneration             7 (12%)      2 (20%)                                                         
      Respiratory Epithelium, Inflammation            11 (18%)                                                                      
      Respiratory Epithelium, Metaplasia, Squamous     2 (3%)                                                                       
      Squamous Epithelium, Hyperplasia                 1 (2%)                                                                       
      Squamous Epithelium, Inflammation                1 (2%)                                                                       
   Trachea                                            (59)         (5)                                                              
      Degeneration                                     1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   12                                                              
NTP Experiment-Test: 05122-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                     NICKEL SULFATE HEXAHYDRATE                                Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 03:47:06  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        1.0          1.0MG/M3                                                            
                                                   MG/M3        LUNG TOX                                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (60)         (10)                                                             
      Fibrosis                                         1 (2%)                                                                       
      Nephropathy                                      3 (5%)                                                                       
      Pelvis, Dilatation                               2 (3%)                                                                       
      Perirenal Tissue, Inflammation                   1 (2%)                                                                       
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   13                                                              
NTP Experiment-Test: 05122-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                     NICKEL SULFATE HEXAHYDRATE                                Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 03:47:06  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          0.0          0.0MG/M3     0.25         .25MG/M3     0.5          0.5MG/M3        
                                                   MG/M3        LUNG TOX     MG/M3        LUNG TOX     MG/M3        LUNG TOX        
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially In Study                          60           20           60           20           60           20           
  Scheduled Sacrifice                                              19                        19                        18           
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                29            1           29                        28            1           
    Natural Death                                      5                         8            1            8            1           
  Survivors                                                                                                                         
    Terminal Sacrifice                                26                        23                        24                        
  Animals Examined Microscopically                    60           11           60           11           60           12           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Esophagus                                          (59)         (5)          (60)         (6)          (59)         (7)          
      Hyperkeratosis                                   1 (2%)       1 (20%)                                1 (2%)                   
   Gallbladder                                        (55)         (6)          (58)         (6)          (54)         (7)          
      Autolysis                                                                  3 (5%)                    1 (2%)                   
   Intestine Large, Colon                             (59)         (6)          (60)         (6)          (58)         (7)          
      Autolysis                                                                  1 (2%)                                             
      Hemorrhage                                       1 (2%)                                                                       
   Intestine Large, Rectum                            (54)         (5)          (56)         (5)          (49)         (5)          
      Autolysis                                                                  1 (2%)                                             
      Anus, Inflammation                                                         1 (2%)                                             
   Intestine Large, Cecum                             (58)         (6)          (59)         (5)          (58)         (7)          
      Autolysis                                                                  1 (2%)                    1 (2%)       1 (14%)     
      Hyperplasia, Lymphoid                            1 (2%)                                                                       
   Intestine Small, Duodenum                          (60)         (6)          (59)         (5)          (57)         (7)          
      Autolysis                                                                  1 (2%)                                             
   Intestine Small, Jejunum                           (60)         (6)          (60)         (6)          (57)         (7)          
      Autolysis                                                                  1 (2%)                                             
      Peyer's Patch, Hyperplasia                       1 (2%)                                              1 (2%)                   
      Peyer's Patch, Inflammation                                                1 (2%)                                             
   Intestine Small, Ileum                             (58)         (6)          (59)         (5)          (55)         (7)          
      Autolysis                                                                  1 (2%)                                             
   Liver                                              (60)         (6)          (60)         (7)          (60)         (8)          
      Angiectasis, Focal                                                                                   1 (2%)                   
      Autolysis                                                                                            2 (3%)                   
      Basophilic Focus                                 2 (3%)                    4 (7%)                    1 (2%)                   
      Clear Cell Focus                                 1 (2%)                                                                       
      Congestion                                       1 (2%)                                              1 (2%)                   
      Cyst                                                                       1 (2%)                                             
      Eosinophilic Focus                                                                                   1 (2%)                   
      Fatty Change                                                               1 (2%)                                             
      Infarct                                          5 (8%)                    1 (2%)                    1 (2%)                   
      Infarct, Focal                                                                          1 (14%)                               
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   14                                                              
NTP Experiment-Test: 05122-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                     NICKEL SULFATE HEXAHYDRATE                                Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 03:47:06  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          0.0          0.0MG/M3     0.25         .25MG/M3     0.5          0.5MG/M3        
                                                   MG/M3        LUNG TOX     MG/M3        LUNG TOX     MG/M3        LUNG TOX        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Inflammation                                                               1 (2%)                    1 (2%)                   
      Necrosis                                                                   1 (2%)                    1 (2%)                   
      Necrosis, Diffuse                                7 (12%)                   5 (8%)                    7 (12%)                  
      Pigmentation                                                                                         1 (2%)                   
      Centrilobular, Degeneration                      1 (2%)                    1 (2%)                                             
      Hepatocyte, Hyperplasia                                       1 (17%)                   1 (14%)                   1 (13%)     
   Mesentery                                          (1)                       (2)                       (1)                       
      Inflammation                                                                                         1 (100%)                 
   Pancreas                                           (60)         (6)          (59)         (6)          (58)         (7)          
      Atrophy                                                                    1 (2%)                                             
      Autolysis                                                                  1 (2%)                                             
      Cyst                                                                                                 1 (2%)                   
      Inflammation                                                               1 (2%)                                             
      Acinus, Hyperplasia                                                        1 (2%)                                             
   Pharynx                                                         (1)                                                              
      Hyperkeratosis                                                1 (100%)                                                        
   Salivary Glands                                    (60)         (6)          (60)         (6)          (60)         (7)          
      Autolysis                                                                                            1 (2%)                   
   Stomach, Forestomach                               (60)         (6)          (59)         (5)          (60)         (7)          
      Autolysis                                        1 (2%)                                                                       
      Hyperplasia, Squamous                                                                                1 (2%)                   
   Stomach, Glandular                                 (60)         (6)          (59)         (6)          (58)         (7)          
      Autolysis                                                                               1 (17%)      2 (3%)                   
      Inflammation                                                                                         1 (2%)                   
   Tooth                                                                                                  (4)                       
      Peridontal Tissue, Inflammation                                                                      4 (100%)                 
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Heart                                              (60)         (6)          (60)         (6)          (60)         (7)          
      Cardiomyopathy                                   4 (7%)       1 (17%)      2 (3%)                    3 (5%)                   
      Inflammation                                     1 (2%)                    1 (2%)                                             
      Atrium, Thrombosis                               2 (3%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (60)         (6)          (59)         (6)          (59)         (7)          
      Accessory Adrenal Cortical Nodule                                          1 (2%)                                             
      Cyst Multilocular                                                          1 (2%)                                             
      Hyperplasia                                      2 (3%)                                              3 (5%)                   
      Hypertrophy                                                                1 (2%)                    1 (2%)                   
      Infarct                                                                                              1 (2%)                   
      Capsule, Hyperplasia                                                       1 (2%)                                             
   Adrenal Medulla                                    (60)         (6)          (57)         (5)          (57)         (7)          
      Infarct                                                                                              1 (2%)                   
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   15                                                              
NTP Experiment-Test: 05122-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                     NICKEL SULFATE HEXAHYDRATE                                Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 03:47:06  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          0.0          0.0MG/M3     0.25         .25MG/M3     0.5          0.5MG/M3        
                                                   MG/M3        LUNG TOX     MG/M3        LUNG TOX     MG/M3        LUNG TOX        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ENDOCRINE SYSTEM - CONT                                                                                                             
   Islets, Pancreatic                                 (60)         (6)          (59)         (6)          (55)         (7)          
      Hyperplasia                                                                                          2 (4%)                   
   Parathyroid Gland                                  (48)         (4)          (41)         (4)          (49)         (6)          
      Autolysis                                                                                            1 (2%)                   
   Pituitary Gland                                    (52)         (6)          (53)         (4)          (56)         (7)          
      Autolysis                                                                                            1 (2%)                   
      Cyst                                                                                                 1 (2%)                   
      Pars Distalis, Hyperplasia                       1 (2%)                    2 (4%)                                             
   Thyroid Gland                                      (60)         (6)          (60)         (6)          (59)         (7)          
      Autolysis                                                                                            1 (2%)                   
      Follicular Cell, Hyperplasia                                                                         1 (2%)                   
      Follicular Cell, Hyperplasia, Cystic            26 (43%)                  26 (43%)                  25 (42%)                  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   Tissue NOS                                         (1)                       (2)                       (1)                       
      Abdominal, Abscess                                                         1 (50%)                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Epididymis                                         (60)         (6)          (60)         (6)          (60)         (7)          
      Autolysis                                                                                            1 (2%)                   
   Penis                                              (4)                       (7)                       (9)                       
      Hyperplasia, Squamous                            4 (100%)                  2 (29%)                   6 (67%)                  
      Inflammation                                                               2 (29%)                   3 (33%)                  
   Preputial Gland                                    (58)         (8)          (58)         (6)          (58)         (9)          
      Atrophy                                          1 (2%)                                              2 (3%)                   
      Cyst                                                                       1 (2%)                                             
      Ectasia                                         44 (76%)      8 (100%)    31 (53%)      5 (83%)     31 (53%)      8 (89%)     
      Inflammation                                    23 (40%)      2 (25%)     35 (60%)      2 (33%)     33 (57%)      1 (11%)     
      Duct, Hyperplasia                                                          1 (2%)                                             
   Prostate                                           (59)         (5)          (59)         (6)          (59)         (6)          
      Autolysis                                                                  1 (2%)                                             
      Congestion                                                                 1 (2%)                                             
      Hyperplasia                                                                                          1 (2%)                   
      Inflammation                                     3 (5%)                    3 (5%)                    3 (5%)                   
   Seminal Vesicle                                    (60)         (6)          (60)         (6)          (59)         (7)          
      Ectasia                                          1 (2%)                    1 (2%)                    1 (2%)                   
      Hemorrhage                                       1 (2%)                                                                       
      Hyperplasia                                                                                          1 (2%)                   
   Testes                                             (60)         (6)          (60)         (6)          (60)         (7)          
      Atrophy                                                                    1 (2%)                    1 (2%)                   
      Autolysis                                                                                            1 (2%)                   
      Granuloma Sperm                                  1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   16                                                              
NTP Experiment-Test: 05122-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                     NICKEL SULFATE HEXAHYDRATE                                Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 03:47:06  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          0.0          0.0MG/M3     0.25         .25MG/M3     0.5          0.5MG/M3        
                                                   MG/M3        LUNG TOX     MG/M3        LUNG TOX     MG/M3        LUNG TOX        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (60)         (6)          (60)         (6)          (59)         (7)          
      Erythroid Cell, Hyperplasia                      1 (2%)                                                                       
      Myeloid Cell, Hyperplasia                       17 (28%)      1 (17%)     15 (25%)                  11 (19%)      1 (14%)     
   Lymph Node                                         (23)         (1)          (21)         (1)          (20)         (2)          
      Iliac, Hyperplasia, Histiocytic                  1 (4%)                                                                       
      Iliac, Hyperplasia, Lymphoid                     4 (17%)                   1 (5%)       1 (100%)     4 (20%)      2 (100%)    
      Iliac, Hyperplasia, Plasma Cell                 12 (52%)                  10 (48%)                   7 (35%)                  
      Iliac, Inflammation                                                        1 (5%)                                             
      Iliac, Pigmentation                              1 (4%)                                                                       
      Inguinal, Hyperplasia, Histiocytic                                                                   2 (10%)                  
      Inguinal, Hyperplasia, Lymphoid                  8 (35%)                  11 (52%)      1 (100%)     7 (35%)                  
      Inguinal, Hyperplasia, Plasma Cell               6 (26%)                   5 (24%)                   4 (20%)                  
      Inguinal, Inflammation                           1 (4%)                    2 (10%)                   1 (5%)                   
      Inguinal, Pigmentation                           2 (9%)                    1 (5%)                                             
      Lumbar, Hyperplasia, Lymphoid                                                                                     1 (50%)     
      Lumbar, Hyperplasia, Plasma Cell                 1 (4%)                                              1 (5%)                   
      Pancreatic, Thrombosis                                                                               1 (5%)                   
      Popliteal, Hyperplasia, Plasma Cell              1 (4%)                                                                       
      Renal, Congestion                                                                                    1 (5%)                   
      Renal, Hyperplasia, Histiocytic                                                                      1 (5%)                   
      Renal, Hyperplasia, Lymphoid                     1 (4%)                                                                       
      Renal, Hyperplasia, Plasma Cell                  4 (17%)      1 (100%)     1 (5%)                    1 (5%)                   
      Renal, Inflammation                              2 (9%)                                              1 (5%)                   
   Lymph Node, Bronchial                              (46)         (9)          (48)         (9)          (44)         (8)          
      Congestion                                                                 1 (2%)                    1 (2%)                   
      Edema                                            1 (2%)                                                                       
      Hematopoietic Cell Proliferation                                           1 (2%)                                             
      Hyperplasia, Histiocytic                                                   2 (4%)                                             
      Hyperplasia, Lymphoid                            2 (4%)       2 (22%)      4 (8%)       4 (44%)      2 (5%)       2 (25%)     
      Hyperplasia, Macrophage                                       1 (11%)                                8 (18%)                  
      Hyperplasia, Plasma Cell                         1 (2%)                    2 (4%)                                             
   Lymph Node, Mandibular                             (55)         (5)          (49)         (6)          (55)         (8)          
      Ectasia                                                                                              1 (2%)                   
      Hyperplasia, Lymphoid                            2 (4%)                    2 (4%)                    4 (7%)                   
      Hyperplasia, Plasma Cell                         1 (2%)                    3 (6%)                                             
      Inflammation                                                               1 (2%)       1 (17%)                               
   Lymph Node, Mesenteric                             (55)         (5)          (53)         (5)          (55)         (5)          
      Angiectasis                                                                                          2 (4%)                   
      Congestion                                       2 (4%)                    4 (8%)                    1 (2%)                   
      Hematopoietic Cell Proliferation                                           2 (4%)                                             
      Hyperplasia, Histiocytic                                                   2 (4%)                    2 (4%)                   
      Hyperplasia, Lymphoid                                                      4 (8%)                    2 (4%)                   
      Inflammation                                     5 (9%)                    5 (9%)                                             
   Lymph Node, Mediastinal                            (18)                      (24)         (7)          (20)                      
      Hyperplasia, Histiocytic                                                   2 (8%)                                             
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   17                                                              
NTP Experiment-Test: 05122-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                     NICKEL SULFATE HEXAHYDRATE                                Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 03:47:06  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          0.0          0.0MG/M3     0.25         .25MG/M3     0.5          0.5MG/M3        
                                                   MG/M3        LUNG TOX     MG/M3        LUNG TOX     MG/M3        LUNG TOX        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
HEMATOPOIETIC SYSTEM - CONT                                                                                                         
      Hyperplasia, Lymphoid                            1 (6%)                                 1 (14%)                               
      Hyperplasia, Plasma Cell                         1 (6%)                                                                       
      Pigmentation                                                               1 (4%)                                             
   Spleen                                             (60)         (6)          (60)         (6)          (59)         (7)          
      Angiectasis                                                                1 (2%)                                             
      Autolysis                                                                                            1 (2%)                   
      Hematopoietic Cell Proliferation                 9 (15%)                  12 (20%)                  11 (19%)                  
      Hyperplasia, Histiocytic                         1 (2%)                                                                       
      Hyperplasia, Lymphoid                            1 (2%)                    3 (5%)                    1 (2%)                   
      Inflammation                                                               2 (3%)                                             
   Thymus                                             (54)         (5)          (48)         (6)          (51)         (7)          
      Atrophy                                         27 (50%)      1 (20%)     14 (29%)      1 (17%)     17 (33%)      2 (29%)     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Skin                                               (60)         (6)          (60)         (7)          (60)         (7)          
      Hyperkeratosis                                                1 (17%)                                                         
      Hyperplasia, Squamous                                                                                1 (2%)                   
      Inflammation                                     4 (7%)       1 (17%)      1 (2%)                    4 (7%)                   
      Inflammation, Chronic                                                                                1 (2%)                   
      Necrosis                                                                   1 (2%)                                             
      Dermis, Inflammation, Chronic Active                                                                              1 (14%)     
      Foot, Inflammation                               1 (2%)                    1 (2%)                    2 (3%)       1 (14%)     
      Foot, Necrosis                                   1 (2%)                                                                       
      Pinna, Inflammation                                                        1 (2%)                                             
      Prepuce, Edema                                                             1 (2%)                                             
      Prepuce, Hyperplasia, Squamous                   1 (2%)                                                                       
      Prepuce, Inflammation                            8 (13%)                  15 (25%)                  18 (30%)      1 (14%)     
      Subcutaneous Tissue, Inflammation                1 (2%)       1 (17%)                                                         
      Tail, Hyperkeratosis                             1 (2%)                                              1 (2%)                   
      Tail, Inflammation                               5 (8%)                    2 (3%)                    1 (2%)       1 (14%)     
      Tail, Necrosis                                  11 (18%)                   4 (7%)                    5 (8%)       1 (14%)     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (60)         (6)          (60)         (6)          (60)         (7)          
      Femur, Hyperostosis                              2 (3%)                    1 (2%)                    2 (3%)                   
      Femur, Osteoporosis                                                        1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   18                                                              
NTP Experiment-Test: 05122-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                     NICKEL SULFATE HEXAHYDRATE                                Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 03:47:06  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          0.0          0.0MG/M3     0.25         .25MG/M3     0.5          0.5MG/M3        
                                                   MG/M3        LUNG TOX     MG/M3        LUNG TOX     MG/M3        LUNG TOX        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (60)         (6)          (60)         (6)          (60)         (7)          
      Cerebrum, Degeneration                                                                               1 (2%)                   
      Hippocampus, Degeneration                                                                            1 (2%)                   
      Meninges, Inflammation                                                     1 (2%)                                             
      Thalamus, Degeneration                                                                               1 (2%)                   
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Larynx                                             (59)         (5)          (58)         (6)          (56)         (6)          
      Autolysis                                                                                            1 (2%)                   
      Hyperplasia, Squamous                                                                                1 (2%)                   
      Inflammation                                                  1 (20%)                                                         
   Lung                                               (60)         (11)         (60)         (11)         (60)         (12)         
      Autolysis                                                                                            1 (2%)                   
      Congestion                                       2 (3%)                                                                       
      Fibrosis                                         1 (2%)                                              1 (2%)                   
      Hemorrhage                                                                                           1 (2%)                   
      Hyperplasia, Macrophage                          6 (10%)                   9 (15%)      1 (9%)      35 (58%)      5 (42%)     
      Infarct                                                                    1 (2%)                                             
      Inflammation                                     1 (2%)                    2 (3%)                                             
      Inflammation, Acute                                           1 (9%)                                                          
      Inflammation, Chronic Active                     1 (2%)                    2 (3%)                    8 (13%)                  
      Alveolar Epithelium, Hyperplasia                 1 (2%)                    4 (7%)       1 (9%)      19 (32%)                  
      Alveolar Epithelium, Hyperplasia, Focal                       1 (9%)                                                          
      Bronchiole, Hyperplasia                          1 (2%)                                                                       
      Interstitium, Infiltration Cellular              1 (2%)                                              3 (5%)                   
      Interstitium, Inflammation, Focal                             1 (9%)                                                          
   Nose                                               (60)         (11)         (60)         (11)         (59)         (12)         
      Developmental Malformation                                                              1 (9%)                                
      Inflammation, Acute                                           2 (18%)                   2 (18%)                   1 (8%)      
      Glands, Inflammation                                          1 (9%)                                                          
      Olfactory Epithelium, Atrophy                                                                       12 (20%)      1 (8%)      
      Olfactory Epithelium, Degeneration                            2 (18%)      1 (2%)                                             
      Olfactory Epithelium, Inflammation               1 (2%)                                                                       
      Respiratory Epithelium, Degeneration             2 (3%)       2 (18%)      2 (3%)                                             
      Respiratory Epithelium, Inflammation             2 (3%)                    2 (3%)                    5 (8%)                   
      Respiratory Epithelium, Metaplasia, Squamous     1 (2%)                    1 (2%)                                             
      Vomeronasal Organ, Infiltration Cellular,                                                                                     
           Polymorphonuclear                                        1 (9%)                    1 (9%)                                
   Trachea                                            (60)         (6)          (60)         (6)          (59)         (7)          
      Autolysis                                                                                            1 (2%)                   
      Inflammation                                                                                                      1 (14%)     
      Epithelium, Hyperplasia                                                                              1 (2%)                   
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   19                                                              
NTP Experiment-Test: 05122-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                     NICKEL SULFATE HEXAHYDRATE                                Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 03:47:06  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          0.0          0.0MG/M3     0.25         .25MG/M3     0.5          0.5MG/M3        
                                                   MG/M3        LUNG TOX     MG/M3        LUNG TOX     MG/M3        LUNG TOX        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                                                                    (1)                       
      Phthisis Bulbi                                                                                       1 (100%)                 
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (60)         (11)         (60)         (11)         (59)         (12)         
      Congestion                                                                 1 (2%)                                             
      Dilatation                                                                 1 (2%)                                             
      Fibrosis                                                                   1 (2%)                                             
      Hydronephrosis                                                                                       2 (3%)                   
      Inflammation                                     8 (13%)                   7 (12%)                   8 (14%)                  
      Mineralization                                                             1 (2%)                                             
      Nephropathy                                      9 (15%)                   8 (13%)                   9 (15%)                  
      Cortex, Cyst                                                               2 (3%)                    1 (2%)                   
      Pelvis, Dilatation                              16 (27%)                  19 (32%)                   9 (15%)      1 (8%)      
      Renal Tubule, Pigmentation                       1 (2%)                                                                       
   Ureter                                             (2)                                                 (1)                       
      Dilatation                                       1 (50%)                                                                      
      Inflammation                                     1 (50%)                                             1 (100%)                 
   Urethra                                            (10)                      (12)         (1)          (15)                      
      Calculus Micro Observation Only                 10 (100%)                  7 (58%)      1 (100%)    15 (100%)                 
      Inflammation                                     1 (10%)                   4 (33%)                   3 (20%)                  
      Transitional Epithelium, Hyperplasia                                       2 (17%)                                            
   Urinary Bladder                                    (59)         (6)          (59)         (6)          (58)         (7)          
      Autolysis                                                                  1 (2%)                                             
      Calculus Micro Observation Only                  1 (2%)                    2 (3%)                    1 (2%)                   
      Congestion                                                                                                        1 (14%)     
      Dilatation                                       1 (2%)                                                           1 (14%)     
      Hemorrhage                                                                                                        1 (14%)     
      Inflammation                                     7 (12%)                   6 (10%)                   9 (16%)                  
      Transitional Epithelium, Hyperplasia             1 (2%)                    1 (2%)                    1 (2%)                   
      Transitional Epithelium, Metaplasia, Squamous                              1 (2%)                                             
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   20                                                              
NTP Experiment-Test: 05122-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                     NICKEL SULFATE HEXAHYDRATE                                Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 03:47:06  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          1.0          1.0MG/M3                                                            
                                                   MG/M3        LUNG TOX                                                            
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially In Study                          60           20                                                               
  Scheduled Sacrifice                                              18                                                               
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                27                                                                            
    Natural Death                                      8            2                                                               
  Survivors                                                                                                                         
    Terminal Sacrifice                                25                                                                            
  Animals Examined Microscopically                    60           12                                                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Esophagus                                          (59)         (7)                                                              
      Hyperkeratosis                                   1 (2%)                                                                       
   Gallbladder                                        (53)         (6)                                                              
      Autolysis                                        1 (2%)                                                                       
   Intestine Large, Rectum                            (49)         (5)                                                              
      Autolysis                                        1 (2%)                                                                       
      Anus, Inflammation                               1 (2%)                                                                       
   Intestine Large, Cecum                             (57)         (6)                                                              
      Autolysis                                        4 (7%)                                                                       
   Intestine Small, Duodenum                          (55)         (5)                                                              
      Autolysis                                        2 (4%)                                                                       
   Intestine Small, Jejunum                           (58)         (6)                                                              
      Autolysis                                        3 (5%)                                                                       
   Intestine Small, Ileum                             (55)         (6)                                                              
      Autolysis                                        3 (5%)                                                                       
   Liver                                              (59)         (6)                                                              
      Clear Cell Focus                                 1 (2%)                                                                       
      Hepatodiaphragmatic Nodule                       1 (2%)                                                                       
      Infarct                                          3 (5%)                                                                       
      Inflammation                                     1 (2%)                                                                       
      Necrosis                                         1 (2%)       1 (17%)                                                         
      Necrosis, Diffuse                                6 (10%)                                                                      
      Bile Duct, Cyst                                  2 (3%)                                                                       
   Mesentery                                          (1)                                                                           
      Inflammation                                     1 (100%)                                                                     
   Pharynx                                            (2)                                                                           
      Hyperplasia, Squamous                            2 (100%)                                                                     
   Salivary Glands                                    (60)         (6)                                                              
      Autolysis                                        1 (2%)                                                                       
   Stomach, Glandular                                 (59)         (6)                                                              
      Autolysis                                        2 (3%)                                                                       
   Tooth                                              (2)                                                                           
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   21                                                              
NTP Experiment-Test: 05122-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                     NICKEL SULFATE HEXAHYDRATE                                Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 03:47:06  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          1.0          1.0MG/M3                                                            
                                                   MG/M3        LUNG TOX                                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Peridontal Tissue, Inflammation                  2 (100%)                                                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Heart                                              (60)         (6)                                                              
      Cardiomyopathy                                   2 (3%)                                                                       
      Inflammation                                     2 (3%)                                                                       
      Thrombosis                                       1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (59)         (6)                                                              
      Hyperplasia                                      1 (2%)                                                                       
   Parathyroid Gland                                  (43)         (6)                                                              
      Autolysis                                        1 (2%)       1 (17%)                                                         
   Thyroid Gland                                      (60)         (7)                                                              
      Autolysis                                                     1 (14%)                                                         
      Follicular Cell, Hyperplasia, Cystic            25 (42%)                                                                      
      Follicular Cell, Hyperplasia, Focal                           1 (14%)                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Epididymis                                         (59)         (7)                                                              
      Autolysis                                        1 (2%)                                                                       
   Penis                                              (13)                                                                          
      Bacterium                                        1 (8%)                                                                       
      Hyperplasia, Squamous                            3 (23%)                                                                      
      Inflammation                                     8 (62%)                                                                      
   Preputial Gland                                    (59)         (7)                                                              
      Atrophy                                          1 (2%)                                                                       
      Autolysis                                        1 (2%)                                                                       
      Ectasia                                         36 (61%)      7 (100%)                                                        
      Inflammation                                    35 (59%)      3 (43%)                                                         
      Duct, Hyperplasia                                1 (2%)                                                                       
   Prostate                                           (59)         (7)                                                              
      Autolysis                                        1 (2%)                                                                       
      Inflammation                                     1 (2%)       1 (14%)                                                         
   Seminal Vesicle                                    (59)         (7)                                                              
      Autolysis                                        1 (2%)                                                                       
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   22                                                              
NTP Experiment-Test: 05122-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                     NICKEL SULFATE HEXAHYDRATE                                Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 03:47:06  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          1.0          1.0MG/M3                                                            
                                                   MG/M3        LUNG TOX                                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
GENITAL SYSTEM - CONT                                                                                                               
      Ectasia                                          2 (3%)                                                                       
      Inflammation                                                  1 (14%)                                                         
   Testes                                             (59)         (7)                                                              
      Autolysis                                        1 (2%)       1 (14%)                                                         
      Tunic, Inflammation                              2 (3%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (60)         (6)                                                              
      Autolysis                                        1 (2%)                                                                       
      Myeloid Cell, Hyperplasia                       11 (18%)      1 (17%)                                                         
   Lymph Node                                         (25)         (3)                                                              
      Iliac, Hyperplasia, Histiocytic                  1 (4%)                                                                       
      Iliac, Hyperplasia, Lymphoid                                  2 (67%)                                                         
      Iliac, Hyperplasia, Plasma Cell                 11 (44%)      1 (33%)                                                         
      Iliac, Inflammation                                           1 (33%)                                                         
      Inguinal, Hyperplasia, Histiocytic               2 (8%)                                                                       
      Inguinal, Hyperplasia, Lymphoid                 11 (44%)      1 (33%)                                                         
      Inguinal, Hyperplasia, Plasma Cell               3 (12%)                                                                      
      Inguinal, Inflammation                           1 (4%)                                                                       
      Inguinal, Pigmentation                           2 (8%)                                                                       
      Inguinal, Thrombosis                                          1 (33%)                                                         
      Lumbar, Hyperplasia, Plasma Cell                 2 (8%)                                                                       
      Pancreatic, Hyperplasia, Lymphoid                1 (4%)                                                                       
      Renal, Hyperplasia, Lymphoid                     2 (8%)       1 (33%)                                                         
   Lymph Node, Bronchial                              (53)         (11)                                                             
      Congestion                                       1 (2%)                                                                       
      Hyperplasia, Lymphoid                           17 (32%)                                                                      
      Hyperplasia, Macrophage                         38 (72%)      5 (45%)                                                         
      Inflammation                                     1 (2%)                                                                       
   Lymph Node, Mandibular                             (44)         (5)                                                              
      Hyperplasia, Lymphoid                            1 (2%)                                                                       
      Hyperplasia, Plasma Cell                         1 (2%)                                                                       
      Inflammation                                     1 (2%)                                                                       
   Lymph Node, Mesenteric                             (53)         (5)                                                              
      Atrophy                                          1 (2%)                                                                       
      Congestion                                       4 (8%)                                                                       
      Edema                                            1 (2%)                                                                       
      Hematopoietic Cell Proliferation                 1 (2%)                                                                       
      Hyperplasia, Lymphoid                            3 (6%)                                                                       
      Inflammation                                     2 (4%)                                                                       
   Lymph Node, Mediastinal                            (23)         (1)                                                              
      Autolysis                                        1 (4%)                                                                       
      Congestion                                       1 (4%)                                                                       
      Hyperplasia, Histiocytic                         1 (4%)                                                                       
      Hyperplasia, Lymphoid                            1 (4%)                                                                       
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   23                                                              
NTP Experiment-Test: 05122-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                     NICKEL SULFATE HEXAHYDRATE                                Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 03:47:06  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          1.0          1.0MG/M3                                                            
                                                   MG/M3        LUNG TOX                                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
HEMATOPOIETIC SYSTEM - CONT                                                                                                         
      Hyperplasia, Plasma Cell                         1 (4%)                                                                       
   Spleen                                             (59)         (6)                                                              
      Hematopoietic Cell Proliferation                10 (17%)      1 (17%)                                                         
      Hyperplasia, Lymphoid                            5 (8%)                                                                       
   Thymus                                             (44)         (6)                                                              
      Atrophy                                         12 (27%)      1 (17%)                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Skin                                               (60)         (6)                                                              
      Inflammation                                     1 (2%)                                                                       
      Necrosis                                         1 (2%)                                                                       
      Ulcer, Chronic Active                                         1 (17%)                                                         
      Foot, Inflammation                               1 (2%)                                                                       
      Prepuce, Inflammation                           12 (20%)      1 (17%)                                                         
      Subcutaneous Tissue, Edema                       1 (2%)                                                                       
      Tail, Inflammation                               2 (3%)                                                                       
      Tail, Necrosis                                   6 (10%)                                                                      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (60)         (7)                                                              
      Autolysis                                                     1 (14%)                                                         
      Congestion                                       1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Larynx                                             (60)         (5)                                                              
      Autolysis                                                     1 (20%)                                                         
      Hyperplasia, Squamous                            1 (2%)                                                                       
   Lung                                               (60)         (11)                                                             
      Hemorrhage                                       1 (2%)                                                                       
      Hyperplasia, Macrophage                         58 (97%)     11 (100%)                                                        
      Inflammation, Chronic Active                    28 (47%)      5 (45%)                                                         
      Thrombosis, Multiple                             1 (2%)                                                                       
      Alveolar Epithelium, Hyperplasia                39 (65%)      5 (45%)                                                         
      Alveolus, Proteinosis                           41 (68%)      4 (36%)                                                         
      Interstitium, Infiltration Cellular             17 (28%)      6 (55%)                                                         
   Nose                                               (59)         (11)                                                             
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   24                                                              
NTP Experiment-Test: 05122-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                     NICKEL SULFATE HEXAHYDRATE                                Date: 05/20/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 03:47:06  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          1.0          1.0MG/M3                                                            
                                                   MG/M3        LUNG TOX                                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
RESPIRATORY SYSTEM - CONT                                                                                                           
      Autolysis                                        1 (2%)                                                                       
      Inflammation, Acute                                           2 (18%)                                                         
      Glands, Inflammation                                          1 (9%)                                                          
      Olfactory Epithelium, Atrophy                   36 (61%)      6 (55%)                                                         
      Olfactory Epithelium, Inflammation                            1 (9%)                                                          
      Respiratory Epithelium, Degeneration             2 (3%)                                                                       
      Respiratory Epithelium, Inflammation             5 (8%)                                                                       
   Trachea                                            (59)         (7)                                                              
      Autolysis                                                     1 (14%)                                                         
      Inflammation                                                  1 (14%)                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (59)         (12)                                                             
      Autolysis                                                     1 (8%)                                                          
      Inflammation                                     6 (10%)      1 (8%)                                                          
      Metaplasia, Osseous                              1 (2%)                                                                       
      Mineralization                                   2 (3%)                                                                       
      Nephropathy                                      8 (14%)                                                                      
      Pelvis, Dilatation                              10 (17%)                                                                      
   Ureter                                             (1)          (1)                                                              
      Inflammation                                     1 (100%)     1 (100%)                                                        
   Urethra                                            (16)                                                                          
      Calculus Micro Observation Only                 14 (88%)                                                                      
      Inflammation                                     5 (31%)                                                                      
   Urinary Bladder                                    (58)         (6)                                                              
      Autolysis                                        3 (5%)                                                                       
      Calculus Micro Observation Only                  2 (3%)                                                                       
      Dilatation                                       2 (3%)                                                                       
      Hemorrhage                                       1 (2%)                                                                       
      Inflammation                                     5 (9%)       1 (17%)                                                         
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   25                                                              
                             ------------------------------------------------------------                                           
                             ----------              END OF REPORT             ----------                                           
                             ------------------------------------------------------------