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TDMS Study 50215-03 Pathology Tables

NTP Experiment-Test: 50215-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                           ACRYLONITRILE                                       Date: 10/31/00
Route: GAVAGE                                                                                                     Time: 12:36:12

                                                          MICE FINAL#1




       Facility:  Battelle Columbus Laboratory

       Chemical CAS #:  107-13-1

       Lock Date:  11/03/99

       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: 50215-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                           ACRYLONITRILE                                       Date: 10/31/00    
Route: GAVAGE                                                                                                     Time: 12:36:12    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE FEMALE                        0 MG/KG       2.5         10 MG/KG     20 MG/KG                                  
                                                                MG/KG                                                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
DISPOSITION SUMMARY                                                                                                                 
                                                                                                                                    
  Animals Initially In Study                          50           50           50           50                                     
  Early Deaths                                                                                                                      
    Natural Death                                      6           15           10           25                                     
    Moribund Sacrifice                                 5            3            1            1                                     
    Dosing Accident                                                                           1                                     
  Survivors                                                                                                                         
    Terminal Sacrifice                                39           32           39           22                                     
    Moribund Sacrifice                                                                        1                                     
                                                                                                                                    
  Animals Examined Microscopically                    50           50           50           50                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Esophagus                                          (50)         (50)         (49)         (50)                                   
      Perforation                                                                             1 (2%)                                
   Gallbladder                                        (50)         (50)         (49)         (50)                                   
      Infiltration Cellular, Lymphocyte                                                       1 (2%)                                
   Intestine Small, Jejunum                           (50)         (50)         (50)         (50)                                   
      Inflammation, Suppurative                                     1 (2%)                                                          
      Peyer's Patch, Hyperplasia, Lymphoid                          1 (2%)       1 (2%)                                             
   Liver                                              (50)         (50)         (50)         (50)                                   
      Angiectasis                                      1 (2%)       3 (6%)       9 (18%)      8 (16%)                               
      Basophilic Focus                                 1 (2%)       6 (12%)      4 (8%)       6 (12%)                               
      Clear Cell Focus                                 5 (10%)      3 (6%)       6 (12%)      5 (10%)                               
      Eosinophilic Focus                               9 (18%)      7 (14%)     18 (36%)     11 (22%)                               
      Hematopoietic Cell Proliferation                 1 (2%)       4 (8%)       3 (6%)       1 (2%)                                
      Hyperplasia                                                   1 (2%)                                                          
      Infarct                                                                    1 (2%)                                             
      Inflammation, Chronic Active                    42 (84%)     34 (68%)     40 (80%)     32 (64%)                               
      Mineralization                                                1 (2%)                    1 (2%)                                
      Mixed Cell Focus                                 3 (6%)      15 (30%)     16 (32%)     13 (26%)                               
      Necrosis                                         1 (2%)       3 (6%)       3 (6%)       6 (12%)                               
      Pigmentation                                     6 (12%)     18 (36%)     13 (26%)      1 (2%)                                
      Vacuolization Cytoplasmic                        9 (18%)     12 (24%)     15 (30%)     21 (42%)                               
      Bile Duct, Cyst                                                                         1 (2%)                                
      Centrilobular, Degeneration                      1 (2%)                                                                       
      Portal, Infiltration Cellular, Lymphocyte        2 (4%)                                                                       
   Mesentery                                          (9)          (10)         (10)         (10)                                   
      Fibrosis                                         1 (11%)                                                                      
      Fat, Inflammation, Chronic Active                1 (11%)      1 (10%)                   1 (10%)                               
      Fat, Necrosis                                    5 (56%)      7 (70%)      8 (80%)      6 (60%)                               
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page    2                                                              
                                                                                                                                   
NTP Experiment-Test: 50215-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                           ACRYLONITRILE                                       Date: 10/31/00    
Route: GAVAGE                                                                                                     Time: 12:36:12    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE FEMALE                        0 MG/KG       2.5         10 MG/KG     20 MG/KG                                  
                                                                MG/KG                                                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
   Pancreas                                           (50)         (50)         (50)         (50)                                   
      Fibrosis                                         1 (2%)                                                                       
      Infiltration Cellular, Mononuclear Cell          2 (4%)       1 (2%)       9 (18%)                                            
      Inflammation, Chronic Active                                  1 (2%)                                                          
      Acinus, Atrophy                                  2 (4%)                                                                       
   Salivary Glands                                    (50)         (50)         (49)         (50)                                   
      Infiltration Cellular, Mononuclear Cell         36 (72%)     32 (64%)     32 (65%)     15 (30%)                               
   Stomach, Forestomach                               (50)         (50)         (50)         (50)                                   
      Erosion, Focal                                                             1 (2%)                                             
      Hyperkeratosis, Diffuse                          1 (2%)                    2 (4%)       3 (6%)                                
      Hyperkeratosis, Focal                            1 (2%)       1 (2%)                    1 (2%)                                
      Inflammation, Chronic Active, Focal                           1 (2%)       2 (4%)       1 (2%)                                
      Inflammation, Chronic Active, Multifocal         1 (2%)       1 (2%)                                                          
      Ulcer, Multifocal                                1 (2%)       1 (2%)                                                          
      Epithelium, Hyperplasia, Focal                   2 (4%)       1 (2%)       5 (10%)      7 (14%)                               
      Epithelium, Hyperplasia, Multifocal                           1 (2%)                                                          
   Stomach, Glandular                                 (50)         (50)         (50)         (50)                                   
      Hyperplasia, Focal                               1 (2%)                    1 (2%)                                             
      Inflammation, Chronic Active                     1 (2%)                                                                       
      Mineralization                                   2 (4%)                    1 (2%)                                             
      Glands, Ectasia                                 11 (22%)     11 (22%)      6 (12%)      6 (12%)                               
   Tooth                                                                        (1)                                                 
      Malformation                                                               1 (100%)                                           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Blood Vessel                                       (50)         (50)         (50)         (50)                                   
      Aorta, Mineralization                            1 (2%)       1 (2%)                    1 (2%)                                
   Heart                                              (50)         (50)         (50)         (50)                                   
      Inflammation, Chronic Active                                  1 (2%)       1 (2%)       3 (6%)                                
      Mineralization                                   1 (2%)       1 (2%)                    1 (2%)                                
      Thrombosis                                                                 1 (2%)                                             
      Valve, Inflammation, Suppurative                              1 (2%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (50)         (50)         (50)         (50)                                   
      Accessory Adrenal Cortical Nodule                1 (2%)                                                                       
      Cyst                                                          1 (2%)                                                          
      Hematopoietic Cell Proliferation                 1 (2%)       2 (4%)                                                          
      Hyperplasia                                      1 (2%)       1 (2%)       1 (2%)       1 (2%)                                
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page    3                                                              
                                                                                                                                   
NTP Experiment-Test: 50215-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                           ACRYLONITRILE                                       Date: 10/31/00    
Route: GAVAGE                                                                                                     Time: 12:36:12    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE FEMALE                        0 MG/KG       2.5         10 MG/KG     20 MG/KG                                  
                                                                MG/KG                                                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ENDOCRINE SYSTEM - CONT                                                                                                             
      Hypertrophy                                                                             1 (2%)                                
      Inflammation, Chronic Active                                                            1 (2%)                                
      Metaplasia, Osseous                                           1 (2%)                                                          
      Subcapsular, Hyperplasia                        50 (100%)    49 (98%)     47 (94%)     49 (98%)                               
   Adrenal Medulla                                    (50)         (50)         (50)         (50)                                   
      Hyperplasia                                      1 (2%)                                                                       
   Parathyroid Gland                                  (43)         (39)         (37)         (34)                                   
      Cyst                                             1 (2%)       1 (3%)                                                          
   Pituitary Gland                                    (48)         (49)         (48)         (49)                                   
      Pars Distalis, Angiectasis                                    1 (2%)       1 (2%)                                             
      Pars Distalis, Cyst                                                        1 (2%)                                             
      Pars Distalis, Hyperplasia                      10 (21%)      8 (16%)      6 (13%)      2 (4%)                                
      Pars Distalis, Pigmentation                                   1 (2%)                                                          
   Thyroid Gland                                      (50)         (50)         (49)         (50)                                   
      Infiltration Cellular, Lymphocyte                             1 (2%)                                                          
      Follicle, Cyst                                   6 (12%)      4 (8%)       3 (6%)       1 (2%)                                
      Follicular Cell, Hyperplasia                     1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Clitoral Gland                                     (50)         (48)         (49)         (48)                                   
      Infiltration Cellular, Mononuclear Cell          2 (4%)                                                                       
      Inflammation, Chronic Active                     3 (6%)       1 (2%)                    1 (2%)                                
      Pigmentation                                                  1 (2%)                                                          
      Duct, Cyst                                                                 1 (2%)                                             
   Ovary                                              (50)         (50)         (50)         (50)                                   
      Angiectasis                                      1 (2%)       1 (2%)       2 (4%)                                             
      Atrophy                                          6 (12%)      8 (16%)     45 (90%)     40 (80%)                               
      Cyst                                            12 (24%)     20 (40%)     27 (54%)     19 (38%)                               
      Mineralization                                                             2 (4%)       2 (4%)                                
      Pigmentation                                                  1 (2%)       3 (6%)       2 (4%)                                
      Thrombosis                                                                              2 (4%)                                
   Uterus                                             (50)         (50)         (50)         (50)                                   
      Angiectasis                                      1 (2%)       2 (4%)       3 (6%)       1 (2%)                                
      Cyst                                                          1 (2%)                                                          
      Inflammation, Suppurative                        1 (2%)       2 (4%)                                                          
      Endometrium, Hyperplasia, Cystic                40 (80%)     41 (82%)     29 (58%)     19 (38%)                               
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page    4                                                              
                                                                                                                                   
NTP Experiment-Test: 50215-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                           ACRYLONITRILE                                       Date: 10/31/00    
Route: GAVAGE                                                                                                     Time: 12:36:12    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE FEMALE                        0 MG/KG       2.5         10 MG/KG     20 MG/KG                                  
                                                                MG/KG                                                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
GENITAL SYSTEM - CONT                                                                                                               
      Lymphatic, Angiectasis                           1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (50)         (50)         (50)         (50)                                   
      Myelofibrosis                                    1 (2%)       1 (2%)                    1 (2%)                                
      Myeloid Cell, Hyperplasia                        1 (2%)       5 (10%)      3 (6%)       5 (10%)                               
   Lymph Node                                         (37)         (32)         (30)         (25)                                   
      Inguinal, Hyperplasia, Lymphoid                                            1 (3%)                                             
      Mediastinal, Hematopoietic Cell Proliferation                 1 (3%)                                                          
      Mediastinal, Hyperplasia, Lymphoid               2 (5%)       4 (13%)      5 (17%)      4 (16%)                               
      Renal, Hematopoietic Cell Proliferation                       1 (3%)                                                          
      Renal, Hyperplasia, Lymphoid                                  1 (3%)                                                          
   Lymph Node, Mandibular                             (49)         (49)         (47)         (50)                                   
      Angiectasis                                                                             1 (2%)                                
      Hematopoietic Cell Proliferation                              1 (2%)                                                          
      Hyperplasia, Lymphoid                            4 (8%)       7 (14%)     12 (26%)      9 (18%)                               
   Lymph Node, Mesenteric                             (50)         (49)         (50)         (47)                                   
      Angiectasis                                                   1 (2%)                                                          
      Ectasia                                          1 (2%)                    2 (4%)                                             
      Hematopoietic Cell Proliferation                 1 (2%)       1 (2%)       1 (2%)                                             
      Hyperplasia, Lymphoid                            3 (6%)       1 (2%)       3 (6%)       1 (2%)                                
      Hyperplasia, Plasma Cell                                      1 (2%)                                                          
      Infiltration Cellular, Polymorphonuclear                      1 (2%)       1 (2%)                                             
      Inflammation, Chronic Active                     1 (2%)       2 (4%)                                                          
   Spleen                                             (50)         (50)         (50)         (50)                                   
      Hematopoietic Cell Proliferation                17 (34%)     23 (46%)     24 (48%)     21 (42%)                               
      Hyperplasia, Lymphoid                           18 (36%)     16 (32%)     17 (34%)     10 (20%)                               
   Thymus                                             (50)         (50)         (47)         (50)                                   
      Atrophy                                          6 (12%)     11 (22%)      4 (9%)      10 (20%)                               
      Ectopic Parathyroid Gland                        1 (2%)       2 (4%)                                                          
      Hyperplasia, Lymphoid                            1 (2%)                    2 (4%)                                             
      Thymocyte, Necrosis                              1 (2%)                                 1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (50)         (50)         (50)         (50)                                   
      Hyperplasia                                                   1 (2%)                                                          
   Skin                                               (50)         (50)         (50)         (50)                                   
      Inflammation, Chronic Active                                  1 (2%)                    1 (2%)                                
      Ulcer                                                         1 (2%)                                                          
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page    5                                                              
                                                                                                                                   
NTP Experiment-Test: 50215-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                           ACRYLONITRILE                                       Date: 10/31/00    
Route: GAVAGE                                                                                                     Time: 12:36:12    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE FEMALE                        0 MG/KG       2.5         10 MG/KG     20 MG/KG                                  
                                                                MG/KG                                                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
INTEGUMENTARY SYSTEM - CONT                                                                                                         
      Epidermis, Hyperplasia                                        1 (2%)                                                          
      Subcutaneous Tissue, Fibrosis                    1 (2%)       2 (4%)       1 (2%)                                             
      Subcutaneous Tissue, Hemorrhage                               1 (2%)                                                          
      Subcutaneous Tissue, Infiltration Cellular,                                                                                   
           Mast Cell                                                1 (2%)                                                          
      Subcutaneous Tissue, Inflammation, Chronic                                                                                    
          Active                                                    2 (4%)       1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Skeletal Muscle                                    (3)          (3)          (2)          (1)                                    
      Inflammation, Chronic Active                                  1 (33%)                                                         
      Arteriole, Mineralization                                     1 (33%)                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Lung                                               (50)         (50)         (50)         (50)                                   
      Erythrophagocytosis                              1 (2%)                                 1 (2%)                                
      Fibrosis                                                                                1 (2%)                                
      Hemorrhage                                                                 1 (2%)                                             
      Inflammation, Chronic Active                     1 (2%)       3 (6%)       1 (2%)       1 (2%)                                
      Inflammation, Suppurative                                     2 (4%)                    2 (4%)                                
      Mineralization                                   1 (2%)       1 (2%)                                                          
      Necrosis                                                                   1 (2%)                                             
      Pigmentation                                                               1 (2%)       1 (2%)                                
      Thrombosis                                                    2 (4%)                                                          
      Alveolar Epithelium, Hyperplasia                 2 (4%)       2 (4%)       4 (8%)                                             
      Alveolus, Infiltration Cellular, Histiocyte      2 (4%)       3 (6%)       4 (8%)       4 (8%)                                
      Mediastinum, Inflammation, Chronic Active                     1 (2%)                                                          
   Nose                                               (50)         (50)         (50)         (50)                                   
      Nasolacrimal Duct, Inflammation, Suppurative     1 (2%)                                 1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                             (1)          (2)          (9)                                    
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page    6                                                              
                                                                                                                                   
NTP Experiment-Test: 50215-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                           ACRYLONITRILE                                       Date: 10/31/00    
Route: GAVAGE                                                                                                     Time: 12:36:12    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE FEMALE                        0 MG/KG       2.5         10 MG/KG     20 MG/KG                                  
                                                                MG/KG                                                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
SPECIAL SENSES SYSTEM - CONT                                                                                                        
      Atrophy                                                       1 (100%)     1 (50%)      7 (78%)                               
      Synechia                                                                   1 (50%)      1 (11%)                               
      Cornea, Inflammation, Chronic Active                          1 (100%)                  5 (56%)                               
      Lens, Cataract                                                                          2 (22%)                               
      Retina, Degeneration                                                       1 (50%)                                            
   Harderian Gland                                    (49)         (50)         (49)         (49)                                   
      Hyperplasia                                      5 (10%)      4 (8%)       6 (12%)      7 (14%)                               
      Infiltration Cellular, Mononuclear Cell         40 (82%)     30 (60%)     33 (67%)     23 (47%)                               
      Bilateral, Hyperplasia                                                                  1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (50)         (50)         (50)         (50)                                   
      Infarct                                          2 (4%)       3 (6%)                                                          
      Inflammation, Chronic Active                     2 (4%)       2 (4%)                                                          
      Metaplasia, Osseous                              2 (4%)       1 (2%)                    1 (2%)                                
      Mineralization                                   4 (8%)       3 (6%)       2 (4%)       4 (8%)                                
      Nephropathy                                     14 (28%)      6 (12%)     10 (20%)      5 (10%)                               
      Cortex, Cyst                                                  2 (4%)       2 (4%)       1 (2%)                                
      Cortex, Hydronephrosis                                                     1 (2%)                                             
      Medulla, Cyst                                    1 (2%)                                                                       
      Renal Tubule, Hyperplasia                                     1 (2%)                                                          
      Renal Tubule, Vacuolization Cytoplasmic          1 (2%)                                                                       
                                                                                                                                    
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page    7                                                              
                                                                                                                                   
NTP Experiment-Test: 50215-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                           ACRYLONITRILE                                       Date: 10/31/00    
Route: GAVAGE                                                                                                     Time: 12:36:12    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE MALE                          0 MG/KG       2.5         10 MG/KG     20 MG/KG                                  
                                                                MG/KG                                                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
DISPOSITION SUMMARY                                                                                                                 
                                                                                                                                    
  Animals Initially In Study                          50           50           50           50                                     
  Early Deaths                                                                                                                      
    Natural Death                                     11            3            8           32                                     
    Moribund Sacrifice                                 1            3            3            4                                     
    Dosing Accident                                                 2                                                               
  Survivors                                                                                                                         
    Terminal Sacrifice                                38           42           39           14                                     
                                                                                                                                    
  Animals Examined Microscopically                    50           50           50           50                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Esophagus                                          (50)         (50)         (50)         (50)                                   
      Inflammation, Suppurative                                     1 (2%)                                                          
      Perforation                                                   2 (4%)                                                          
   Gallbladder                                        (50)         (49)         (50)         (48)                                   
      Cyst                                                                                    1 (2%)                                
   Intestine Large, Cecum                             (50)         (50)         (50)         (50)                                   
      Inflammation, Chronic Active                                               1 (2%)                                             
      Ulcer                                                                      1 (2%)                                             
   Intestine Small, Duodenum                          (50)         (50)         (50)         (50)                                   
      Ulcer                                                         1 (2%)                                                          
   Intestine Small, Jejunum                           (50)         (50)         (50)         (50)                                   
      Inflammation, Chronic Active                                               1 (2%)                                             
      Peyer's Patch, Hyperplasia, Lymphoid             2 (4%)       1 (2%)                                                          
   Liver                                              (50)         (50)         (50)         (50)                                   
      Angiectasis                                      1 (2%)       2 (4%)       5 (10%)      1 (2%)                                
      Basophilic Focus                                 1 (2%)       5 (10%)      5 (10%)      4 (8%)                                
      Clear Cell Focus                                19 (38%)     24 (48%)     16 (32%)      4 (8%)                                
      Eosinophilic Focus                               5 (10%)      5 (10%)     10 (20%)      4 (8%)                                
      Fibrosis                                                                   1 (2%)       1 (2%)                                
      Hematopoietic Cell Proliferation                 2 (4%)       2 (4%)       1 (2%)       1 (2%)                                
      Infarct                                          2 (4%)       1 (2%)       2 (4%)                                             
      Inflammation, Chronic Active                    25 (50%)     33 (66%)     33 (66%)     11 (22%)                               
      Mineralization                                                1 (2%)       1 (2%)                                             
      Mixed Cell Focus                                 9 (18%)     13 (26%)     13 (26%)      3 (6%)                                
      Necrosis                                         4 (8%)      10 (20%)      5 (10%)                                            
      Pigmentation                                                  4 (8%)       3 (6%)                                             
      Vacuolization Cytoplasmic                       18 (36%)     30 (60%)     23 (46%)     17 (34%)                               
      Centrilobular, Degeneration                      1 (2%)                                                                       
   Mesentery                                          (8)          (6)          (8)          (3)                                    
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page    8                                                              
                                                                                                                                   
NTP Experiment-Test: 50215-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                           ACRYLONITRILE                                       Date: 10/31/00    
Route: GAVAGE                                                                                                     Time: 12:36:12    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE MALE                          0 MG/KG       2.5         10 MG/KG     20 MG/KG                                  
                                                                MG/KG                                                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Artery, Inflammation, Chronic Active                                       1 (13%)                                            
      Artery, Necrosis, Fibrinoid                                                1 (13%)                                            
      Fat, Inflammation, Chronic Active                1 (13%)                                                                      
      Fat, Mineralization                                                        2 (25%)                                            
      Fat, Necrosis                                    2 (25%)      3 (50%)      4 (50%)      2 (67%)                               
   Oral Mucosa                                        (2)                       (4)          (1)                                    
      Gingival, Foreign Body                           2 (100%)                  3 (75%)                                            
      Gingival, Inflammation, Suppurative              2 (100%)                  4 (100%)     1 (100%)                              
   Pancreas                                           (50)         (50)         (50)         (50)                                   
      Infiltration Cellular, Mononuclear Cell          1 (2%)       2 (4%)       1 (2%)                                             
      Inflammation, Chronic Active                     1 (2%)                                                                       
      Acinus, Atrophy                                               1 (2%)                    1 (2%)                                
   Salivary Glands                                    (50)         (50)         (50)         (50)                                   
      Infiltration Cellular, Mononuclear Cell         35 (70%)     34 (68%)     36 (72%)     23 (46%)                               
      Duct, Cyst                                                                 1 (2%)                                             
   Stomach, Forestomach                               (50)         (50)         (50)         (50)                                   
      Hyperkeratosis, Diffuse                                                    3 (6%)       6 (12%)                               
      Hyperkeratosis, Focal                            2 (4%)       3 (6%)       4 (8%)       6 (12%)                               
      Hyperplasia                                                                             1 (2%)                                
      Inflammation, Chronic Active                                               1 (2%)                                             
      Inflammation, Chronic Active, Focal              1 (2%)       2 (4%)                    2 (4%)                                
      Inflammation, Chronic Active, Multifocal                      1 (2%)       1 (2%)                                             
      Ulcer                                                         1 (2%)       1 (2%)       1 (2%)                                
      Ulcer, Multifocal                                             2 (4%)       1 (2%)                                             
      Epithelium, Hyperplasia, Focal                   2 (4%)       4 (8%)       8 (16%)      9 (18%)                               
   Stomach, Glandular                                 (50)         (50)         (50)         (50)                                   
      Hyperplasia, Focal                               1 (2%)       1 (2%)                    1 (2%)                                
      Inflammation, Chronic Active                                  2 (4%)                                                          
      Mineralization                                                             1 (2%)                                             
      Ulcer                                            1 (2%)                                                                       
      Glands, Ectasia                                  2 (4%)       7 (14%)     11 (22%)      4 (8%)                                
   Tooth                                              (9)          (5)          (4)          (3)                                    
      Inflammation, Suppurative                                                  1 (25%)                                            
      Malformation                                     9 (100%)     5 (100%)     3 (75%)      2 (67%)                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Blood Vessel                                       (50)         (50)         (50)         (50)                                   
      Aorta, Mineralization                                                      1 (2%)                                             
   Heart                                              (50)         (50)         (50)         (50)                                   
      Inflammation, Chronic Active                     1 (2%)       3 (6%)       2 (4%)       1 (2%)                                
      Inflammation, Suppurative                                                  1 (2%)                                             
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page    9                                                              
                                                                                                                                   
NTP Experiment-Test: 50215-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                           ACRYLONITRILE                                       Date: 10/31/00    
Route: GAVAGE                                                                                                     Time: 12:36:12    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE MALE                          0 MG/KG       2.5         10 MG/KG     20 MG/KG                                  
                                                                MG/KG                                                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
CARDIOVASCULAR SYSTEM - CONT                                                                                                        
      Mineralization                                   2 (4%)                                 1 (2%)                                
      Valve, Inflammation, Chronic Active                                        1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (50)         (50)         (50)         (50)                                   
      Hypertrophy                                     19 (38%)     21 (42%)     19 (38%)      2 (4%)                                
      Subcapsular, Cyst Multilocular                   1 (2%)                                                                       
      Subcapsular, Hyperplasia                        45 (90%)     43 (86%)     40 (80%)     36 (72%)                               
   Adrenal Medulla                                    (50)         (50)         (50)         (50)                                   
      Hyperplasia                                                   1 (2%)       1 (2%)                                             
   Parathyroid Gland                                  (42)         (44)         (34)         (41)                                   
      Cyst                                             2 (5%)                                 1 (2%)                                
   Pituitary Gland                                    (49)         (46)         (47)         (47)                                   
      Pars Distalis, Cyst                              3 (6%)       2 (4%)       3 (6%)       2 (4%)                                
   Thyroid Gland                                      (50)         (50)         (50)         (50)                                   
      Follicle, Cyst                                   3 (6%)       3 (6%)       5 (10%)      1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Epididymis                                         (50)         (50)         (50)         (50)                                   
      Atrophy                                          1 (2%)                                 1 (2%)                                
      Granuloma Sperm                                  1 (2%)       1 (2%)                                                          
      Infiltration Cellular, Mononuclear Cell         42 (84%)     31 (62%)     38 (76%)     16 (32%)                               
      Inflammation, Chronic Active                     2 (4%)                    1 (2%)                                             
      Inflammation, Suppurative                                                  1 (2%)                                             
      Mineralization                                   1 (2%)                                                                       
   Preputial Gland                                    (49)         (50)         (50)         (50)                                   
      Hyperplasia, Basal Cell                                                    1 (2%)                                             
      Infiltration Cellular, Mononuclear Cell         11 (22%)     13 (26%)     11 (22%)     13 (26%)                               
      Inflammation, Chronic Active                     8 (16%)      3 (6%)       8 (16%)      2 (4%)                                
      Bilateral, Inflammation, Chronic Active          1 (2%)                                                                       
      Bilateral, Duct, Ectasia                         4 (8%)       1 (2%)       2 (4%)       1 (2%)                                
      Duct, Ectasia                                   13 (27%)     10 (20%)     20 (40%)     15 (30%)                               
   Prostate                                           (50)         (50)         (50)         (50)                                   
      Infiltration Cellular, Mononuclear Cell         36 (72%)     31 (62%)     29 (58%)     22 (44%)                               
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page   10                                                              
                                                                                                                                   
NTP Experiment-Test: 50215-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                           ACRYLONITRILE                                       Date: 10/31/00    
Route: GAVAGE                                                                                                     Time: 12:36:12    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE MALE                          0 MG/KG       2.5         10 MG/KG     20 MG/KG                                  
                                                                MG/KG                                                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
GENITAL SYSTEM - CONT                                                                                                               
      Inflammation, Chronic Active                     2 (4%)       2 (4%)                                                          
      Metaplasia, Mucous                                                                      1 (2%)                                
      Mineralization                                                             1 (2%)                                             
   Seminal Vesicle                                    (50)         (50)         (50)         (50)                                   
      Atrophy                                                                                 1 (2%)                                
      Inflammation, Chronic Active                     1 (2%)                                                                       
   Testes                                             (50)         (50)         (50)         (50)                                   
      Inflammation, Suppurative                                                  1 (2%)                                             
      Mineralization                                   2 (4%)       1 (2%)       2 (4%)                                             
      Necrosis                                         1 (2%)                                                                       
      Germinal Epithelium, Degeneration                2 (4%)       1 (2%)       3 (6%)       1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (50)         (50)         (50)         (50)                                   
      Angiectasis                                                                2 (4%)                                             
      Atrophy                                                                    1 (2%)                                             
      Inflammation, Suppurative                                                  1 (2%)                                             
      Myeloid Cell, Hyperplasia                                     1 (2%)       4 (8%)       2 (4%)                                
   Lymph Node                                         (6)          (4)          (6)          (5)                                    
      Mediastinal, Hyperplasia, Lymphoid                            1 (25%)      1 (17%)                                            
      Pancreatic, Hyperplasia, Lymphoid                                                       1 (20%)                               
   Lymph Node, Mandibular                             (49)         (47)         (47)         (47)                                   
      Hematopoietic Cell Proliferation                              1 (2%)                                                          
      Hyperplasia, Lymphoid                            1 (2%)       1 (2%)       5 (11%)      4 (9%)                                
   Lymph Node, Mesenteric                             (48)         (48)         (49)         (48)                                   
      Angiectasis                                                                             1 (2%)                                
      Atrophy                                                                                 1 (2%)                                
      Ectasia                                                                                 2 (4%)                                
      Hematopoietic Cell Proliferation                 1 (2%)                                 2 (4%)                                
      Hyperplasia, Lymphoid                            4 (8%)       1 (2%)                                                          
      Hyperplasia, Plasma Cell                                      1 (2%)                                                          
      Inflammation, Chronic Active                     1 (2%)                                 1 (2%)                                
   Spleen                                             (50)         (50)         (50)         (50)                                   
      Depletion Cellular                               1 (2%)                                                                       
      Fibrosis                                                                                1 (2%)                                
      Hematopoietic Cell Proliferation                17 (34%)      7 (14%)     16 (32%)     12 (24%)                               
      Hyperplasia, Lymphoid                            2 (4%)                                                                       
      Lymphoid Follicle, Depletion Cellular                                                   1 (2%)                                
      Red Pulp, Depletion Cellular                                  1 (2%)                                                          
   Thymus                                             (47)         (47)         (44)         (46)                                   
      Atrophy                                          7 (15%)      4 (9%)       7 (16%)      4 (9%)                                
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page   11                                                              
                                                                                                                                   
NTP Experiment-Test: 50215-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                           ACRYLONITRILE                                       Date: 10/31/00    
Route: GAVAGE                                                                                                     Time: 12:36:12    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE MALE                          0 MG/KG       2.5         10 MG/KG     20 MG/KG                                  
                                                                MG/KG                                                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
HEMATOPOIETIC SYSTEM - CONT                                                                                                         
      Inflammation, Chronic Active                                  1 (2%)                                                          
      Thymocyte, Necrosis                                           1 (2%)                    3 (7%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Skin                                               (50)         (50)         (50)         (50)                                   
      Infiltration Cellular, Mononuclear Cell          1 (2%)                    1 (2%)                                             
      Inflammation, Chronic Active                                               1 (2%)                                             
      Ulcer                                                                      1 (2%)                                             
      Subcutaneous Tissue, Infiltration Cellular,                                                                                   
           Mast Cell                                                1 (2%)                                                          
      Subcutaneous Tissue, Inflammation,                                                                                            
          Suppurative                                                            1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (50)         (50)         (50)         (50)                                   
      Hyperostosis                                                  1 (2%)                    1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (50)         (50)         (50)         (50)                                   
      Cyst Epithelial Inclusion                                                  1 (2%)                                             
      Hemorrhage                                                    2 (4%)                                                          
      Inflammation, Chronic Active                                  1 (2%)                                                          
      Thrombosis                                                    1 (2%)                                                          
      Vacuolization Cytoplasmic                                     1 (2%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Lung                                               (50)         (50)         (50)         (50)                                   
      Erythrophagocytosis                              1 (2%)                    2 (4%)                                             
      Inflammation, Chronic Active                     4 (8%)       1 (2%)       3 (6%)                                             
      Inflammation, Granulomatous                                                             1 (2%)                                
      Inflammation, Suppurative                                     2 (4%)                    1 (2%)                                
      Metaplasia, Osseous                              1 (2%)                                                                       
      Mineralization                                                             1 (2%)                                             
      Necrosis                                         1 (2%)                                                                       
      Pigmentation                                     1 (2%)                    2 (4%)                                             
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page   12                                                              
                                                                                                                                   
NTP Experiment-Test: 50215-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                           ACRYLONITRILE                                       Date: 10/31/00    
Route: GAVAGE                                                                                                     Time: 12:36:12    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE MALE                          0 MG/KG       2.5         10 MG/KG     20 MG/KG                                  
                                                                MG/KG                                                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
RESPIRATORY SYSTEM - CONT                                                                                                           
      Alveolar Epithelium, Hyperplasia                 4 (8%)       3 (6%)       5 (10%)      6 (12%)                               
      Alveolus, Infiltration Cellular, Histiocyte      1 (2%)                    4 (8%)                                             
      Artery, Mediastinum, Mineralization                                        1 (2%)                                             
      Mediastinum, Hemorrhage                                       1 (2%)                                                          
      Mediastinum, Inflammation, Chronic Active        1 (2%)                                                                       
   Nose                                               (50)         (50)         (50)         (50)                                   
      Foreign Body                                                               1 (2%)                                             
      Inflammation, Suppurative                        1 (2%)                    1 (2%)                                             
      Nasolacrimal Duct, Inflammation, Suppurative     4 (8%)       1 (2%)       4 (8%)       7 (14%)                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                             (1)          (6)          (3)                                    
      Atrophy                                                       1 (100%)     4 (67%)      2 (67%)                               
      Synechia                                                                   2 (33%)      2 (67%)                               
      Cornea, Inflammation, Chronic Active                                       3 (50%)      3 (100%)                              
      Cornea, Sclera, Inflammation, Chronic Active                               1 (17%)                                            
      Lens, Cataract                                                1 (100%)     3 (50%)      2 (67%)                               
      Retina, Atrophy                                                            1 (17%)                                            
   Harderian Gland                                    (50)         (50)         (50)         (50)                                   
      Hyperplasia                                      1 (2%)       4 (8%)       7 (14%)      4 (8%)                                
      Infiltration Cellular, Mononuclear Cell         33 (66%)     25 (50%)     26 (52%)     14 (28%)                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (50)         (50)         (50)         (50)                                   
      Accumulation, Hyaline Droplet                                              1 (2%)                                             
      Infarct                                          5 (10%)      3 (6%)       3 (6%)       5 (10%)                               
      Inflammation, Chronic Active                     2 (4%)       3 (6%)       3 (6%)       2 (4%)                                
      Inflammation, Suppurative                                     1 (2%)                                                          
      Metaplasia, Osseous                              5 (10%)      2 (4%)       5 (10%)      3 (6%)                                
      Mineralization                                  23 (46%)     28 (56%)     32 (64%)     18 (36%)                               
      Necrosis                                                      1 (2%)                                                          
      Nephropathy                                     41 (82%)     39 (78%)     42 (84%)     19 (38%)                               
      Artery, Inflammation, Chronic Active                          1 (2%)                                                          
      Cortex, Cyst                                    10 (20%)     13 (26%)     13 (26%)      4 (8%)                                
      Glomerulus, Thrombosis                                                     1 (2%)                                             
      Pelvis, Inflammation, Suppurative                             1 (2%)                                                          
      Renal Tubule, Casts Protein                                                1 (2%)                                             
      Renal Tubule, Hyperplasia                        5 (10%)      5 (10%)      4 (8%)                                             
                                                                                                                                    
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page   13                                                              
                                                                                                                                   
                             ------------------------------------------------------------                                           
                             ----------              END OF REPORT             ----------                                           
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