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https://ntp.niehs.nih.gov/go/1415

TDMS Study 05092-03 Pathology Tables

NTP Experiment-Test: 05092-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: SPECIAL STUDY                                     O-NITROANISOLE                                      Date: 04/08/97
Route: DOSED FEED                                                                                                 Time: 13:45:49




       Facility:  Southern Research Institute

       Chemical CAS #:  0091-23-6

       Lock Date:  None

       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: 05092-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: SPECIAL STUDY                                     O-NITROANISOLE                                      Date: 04/08/97  
Route: DOSED FEED                                                                                                 Time: 13:45:49  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS FEMALE                   0.0%         0.0%         0.0%         0.0%         0.0%         0.600%          
                                                                 3 SSAC       6 SSAC       9 SSAC       15 SSAC                     
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially In Study                          20           10           10           10           10           20           
  Scheduled Sacrifice                                              10           10           10            8                        
  Early Deaths                                                                                                                      
    Natural Death                                      2                                                                4           
    Moribund Sacrifice                                 4                                                   2           12           
  Survivors                                                                                                                         
    Terminal Sacrifice                                14                                                                4           
  Animals Examined Microscopically                    20           10           10           10           10           20           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Intestine Large, Rectum                            (1)                                                              (5)          
      Parasite Metazoan                                                                                                 1 (20%)     
   Liver                                              (20)         (10)         (10)         (10)         (10)         (20)         
      Basophilic Focus                                 1 (5%)                                 5 (50%)                   2 (10%)     
      Basophilic Focus, Multiple                      14 (70%)                                             7 (70%)      9 (45%)     
      Eosinophilic Focus                               4 (20%)                                                          1 (5%)      
      Eosinophilic Focus, Multiple                     1 (5%)                                                           1 (5%)      
      Hematopoietic Cell Proliferation                                                                     1 (10%)                  
      Hepatodiaphragmatic Nodule                       2 (10%)      1 (10%)                                             3 (15%)     
      Inflammation, Granulomatous, Multifocal                                    1 (10%)                                            
      Inflammation, Granulomatous, Multiple           14 (70%)                   4 (40%)      5 (50%)      2 (20%)     10 (50%)     
      Mixed Cell Focus                                 4 (20%)                                                          1 (5%)      
      Vacuolization Cytoplasmic                        3 (15%)      1 (10%)                                                         
      Bile Duct, Hyperplasia                           5 (25%)                                             2 (20%)      1 (5%)      
      Hepatocyte, Hypertrophy                                                                              3 (30%)      2 (10%)     
      Hepatocyte, Mitotic Alteration                                                                       1 (10%)                  
      Hepatocyte, Necrosis, Multifocal                              1 (10%)                                                         
      Hepatocyte, Kupffer Cell, Pigmentation           8 (40%)                                1 (10%)      1 (10%)      2 (10%)     
   Mesentery                                          (1)                       (1)                       (2)          (2)          
      Fat, Necrosis, Focal                             1 (100%)                  1 (100%)                  2 (100%)     2 (100%)    
   Stomach, Forestomach                               (5)                                                              (9)          
      Diverticulum                                     1 (20%)                                                                      
      Edema                                            1 (20%)                                                          1 (11%)     
      Ulcer                                            1 (20%)                                                                      
      Epithelium, Hyperplasia                          2 (40%)                                                          4 (44%)     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    2                                                              
NTP Experiment-Test: 05092-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: SPECIAL STUDY                                     O-NITROANISOLE                                      Date: 04/08/97  
Route: DOSED FEED                                                                                                 Time: 13:45:49  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS FEMALE                   0.0%         0.0%         0.0%         0.0%         0.0%         0.600%          
                                                                 3 SSAC       6 SSAC       9 SSAC       15 SSAC                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Heart                                                                                                               (2)          
      Inflammation, Chronic                                                                                             1 (50%)     
      Mineralization, Multifocal                                                                                        1 (50%)     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Gland, Cortex                              (2)                                                                           
      Bilateral, Vacuolization Cytoplasmic             1 (50%)                                                                      
   Pituitary Gland                                    (12)                                                (1)          (8)          
      Pars Distalis, Cyst                                                                                               1 (13%)     
      Pars Distalis, Hemorrhage                        3 (25%)                                                                      
      Pars Distalis, Hyperplasia, Focal                                                                                 2 (25%)     
   Thyroid Gland                                      (1)                                                              (1)          
      C-Cell, Hyperplasia                                                                                               1 (100%)    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Clitoral Gland                                     (3)                                                 (2)          (5)          
      Inflammation, Suppurative                        1 (33%)                                                                      
      Duct, Cyst                                                                                                        5 (100%)    
   Ovary                                              (1)                                    (1)          (1)                       
      Cyst                                             1 (100%)                               1 (100%)     1 (100%)                 
   Uterus                                             (19)         (10)         (10)         (10)         (10)         (20)         
      Atrophy                                                                                                           1 (5%)      
      Dilatation                                       2 (11%)                                1 (10%)      2 (20%)      2 (10%)     
      Fibrosis, Focal                                  1 (5%)                                                                       
      Inflammation, Suppurative                        2 (11%)                                                                      
      Cervix, Cyst                                     1 (5%)                                                                       
      Cervix, Myometrium, Hypertrophy                  1 (5%)                                                           2 (10%)     
      Endometrium, Hyperplasia, Cystic                 3 (16%)                                                          2 (10%)     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Lymph Node                                         (14)                                                             (16)         
      Deep Cervical, Angiectasis                       1 (7%)                                                                       
      Iliac, Hyperplasia, Lymphoid                                                                                      1 (6%)      
      Mediastinal, Angiectasis                         2 (14%)                                                          9 (56%)     
      Mediastinal, Hyperplasia, Lymphoid               1 (7%)                                                           1 (6%)      
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    3                                                              
NTP Experiment-Test: 05092-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: SPECIAL STUDY                                     O-NITROANISOLE                                      Date: 04/08/97  
Route: DOSED FEED                                                                                                 Time: 13:45:49  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS FEMALE                   0.0%         0.0%         0.0%         0.0%         0.0%         0.600%          
                                                                 3 SSAC       6 SSAC       9 SSAC       15 SSAC                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
HEMATOPOIETIC SYSTEM - CONT                                                                                                         
      Mediastinal, Pigmentation                        3 (21%)                                                          2 (13%)     
      Pancreatic, Angiectasis                          2 (14%)                                                                      
      Pancreatic, Pigmentation                                                                                          1 (6%)      
   Lymph Node, Mandibular                             (7)                                                              (2)          
      Cyst                                             1 (14%)                                                          1 (50%)     
      Cyst, Multiple                                   1 (14%)                                                                      
      Hyperplasia, Lymphoid                            2 (29%)                                                                      
   Spleen                                             (20)         (10)         (10)         (10)         (10)         (20)         
      Atrophy                                                                                                           2 (10%)     
      Congestion                                      11 (55%)                                3 (30%)      5 (50%)      7 (35%)     
      Depletion Lymphoid                               4 (20%)                                                          5 (25%)     
      Hematopoietic Cell Proliferation                15 (75%)                                1 (10%)      4 (40%)     12 (60%)     
      Hyperplasia, Histiocytic, Lymphoid               1 (5%)                                                           1 (5%)      
      Hyperplasia, Lymphoid                                                                                             1 (5%)      
      Pigmentation                                    15 (75%)     10 (100%)     5 (50%)      5 (50%)      6 (60%)     12 (60%)     
      Capsule, Hypertrophy                                                                                              9 (45%)     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (13)                                                (1)          (5)          
      Hyperplasia, Lobular                             8 (62%)                                                          1 (20%)     
      Duct, Cyst                                       9 (69%)                                                          3 (60%)     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (2)                                                              (3)          
      Calvarium, Hyperostosis                          2 (100%)                                                         3 (100%)    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (5)                                                              (2)          
      Compression                                      4 (80%)                                                                      
      Hydrocephalus                                                                                                     1 (50%)     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Lung                                               (2)                                                 (1)          (1)          
      Congestion                                       1 (50%)                                                                      
      Infiltration Cellular, Histiocyte                1 (50%)                                                                      
      Alveolar Epithelium, Hyperplasia                                                                                  1 (100%)    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    4                                                              
NTP Experiment-Test: 05092-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: SPECIAL STUDY                                     O-NITROANISOLE                                      Date: 04/08/97  
Route: DOSED FEED                                                                                                 Time: 13:45:49  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS FEMALE                   0.0%         0.0%         0.0%         0.0%         0.0%         0.600%          
                                                                 3 SSAC       6 SSAC       9 SSAC       15 SSAC                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                (1)                                                                           
      Cataract                                         1 (100%)                                                                     
      Retina, Degeneration                             1 (100%)                                                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (20)         (10)         (10)         (10)         (10)         (20)         
      Hydronephrosis                                                                                                    2 (10%)     
      Inflammation, Suppurative                                                                                         1 (5%)      
      Nephropathy, Chronic                            18 (90%)                                5 (50%)      6 (60%)     12 (60%)     
      Bilateral, Hydronephrosis                                                                                         1 (5%)      
      Corticomedullary Junction, Mineralization                     9 (90%)      2 (20%)                                            
      Papilla, Necrosis                                                                                                 2 (10%)     
      Pelvis, Hemorrhage                                                                                                1 (5%)      
      Pelvis, Inflammation, Suppurative                                                                                 1 (5%)      
      Pelvis, Mineralization                           5 (25%)                                1 (10%)      2 (20%)      4 (20%)     
      Renal Tubule, Mineralization                    17 (85%)                   3 (30%)      9 (90%)      8 (80%)      9 (45%)     
      Renal Tubule, Pigmentation                      18 (90%)                                6 (60%)      9 (90%)     20 (100%)    
      Renal Tubule, Regeneration                                                                                        2 (10%)     
      Transitional Epithelium, Hyperplasia                                                                              5 (25%)     
   Ureter                                             (18)         (10)         (9)          (10)         (9)          (17)         
      Dilatation                                                                                                        5 (29%)     
   Urinary Bladder                                    (18)         (10)         (10)         (10)         (10)         (20)         
      Hemorrhage                                                                                                        2 (10%)     
      Inflammation, Suppurative                                                                                         1 (5%)      
      Metaplasia, Squamous                                                                                              6 (30%)     
      Necrosis                                                                                                          3 (15%)     
      Transitional Epithelium, Hyperplasia                                                                              4 (20%)     
      Wall, Infiltration Cellular, Lipocyte                                                                             3 (15%)     
      Wall, Proliferation Connective Tissue                                                                            11 (55%)     
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    5                                                              
NTP Experiment-Test: 05092-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: SPECIAL STUDY                                     O-NITROANISOLE                                      Date: 04/08/97  
Route: DOSED FEED                                                                                                 Time: 13:45:49  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS FEMALE                   0.600%       0.600%       0.600%       0.600%       1.80%        1.80%           
                                                   3 SSAC       6 SSAC       9 SSAC       15 SSAC                   3 SSAC          
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially In Study                          10           10           10           10           20           10           
  Scheduled Sacrifice                                 10           10           10           10                        10           
  Early Deaths                                                                                                                      
    Natural Death                                                                                          5                        
    Moribund Sacrifice                                                                                    15                        
  Survivors                                                                                                                         
  Animals Examined Microscopically                    10           10           10           10           20           10           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Intestine Large, Colon                                          (1)                       (2)          (10)                      
      Parasite Metazoan                                                                                    1 (10%)                  
      Epithelium, Hyperplasia                                                                              1 (10%)                  
   Liver                                              (10)         (10)         (10)         (9)          (20)         (10)         
      Basophilic Focus                                                           2 (20%)      1 (11%)                               
      Basophilic Focus, Multiple                                                              2 (22%)                               
      Hepatodiaphragmatic Nodule                                    1 (10%)                                1 (5%)       1 (10%)     
      Inflammation, Granulomatous, Multiple                                      5 (50%)      4 (44%)     15 (75%)                  
      Vacuolization Cytoplasmic                                                                                         1 (10%)     
      Bile Duct, Hyperplasia                                                                               1 (5%)                   
      Hepatocyte, Hypertrophy                                                                              1 (5%)      10 (100%)    
      Hepatocyte, Necrosis, Multifocal                 3 (30%)                                             1 (5%)      10 (100%)    
      Hepatocyte, Vacuolization Cytoplasmic                                                                             1 (10%)     
      Hepatocyte, Vacuolization Cytoplasmic,                                                                                        
          Multifocal                                                                                                    1 (10%)     
      Hepatocyte, Kupffer Cell, Pigmentation                        9 (90%)      7 (70%)      2 (22%)     20 (100%)    10 (100%)    
      Kupffer Cell, Pigmentation, Multifocal           1 (10%)                                                                      
   Mesentery                                                                    (1)          (5)          (2)                       
      Fat, Inflammation, Chronic                                                              4 (80%)                               
      Fat, Necrosis, Focal                                                       1 (100%)     1 (20%)                               
   Pancreas                                                                                               (3)                       
      Ectopic Tissue                                                                                       1 (33%)                  
   Stomach, Forestomach                                                         (1)                       (7)                       
      Epithelium, Hyperplasia                                                    1 (100%)                  1 (14%)                  
   Stomach, Glandular                                                           (1)                       (7)                       
      Mineralization                                                                                       1 (14%)                  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    6                                                              
NTP Experiment-Test: 05092-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: SPECIAL STUDY                                     O-NITROANISOLE                                      Date: 04/08/97  
Route: DOSED FEED                                                                                                 Time: 13:45:49  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS FEMALE                   0.600%       0.600%       0.600%       0.600%       1.80%        1.80%           
                                                   3 SSAC       6 SSAC       9 SSAC       15 SSAC                   3 SSAC          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Clitoral Gland                                                                            (1)          (1)                       
      Duct, Cyst                                                                              1 (100%)     1 (100%)                 
   Ovary                                                           (1)                                    (1)                       
      Cyst                                                          1 (100%)                                                        
   Oviduct                                                                                   (1)                                    
      Cyst                                                                                    1 (100%)                              
   Uterus                                             (10)         (10)         (10)         (10)         (20)         (10)         
      Atrophy                                         10 (100%)    10 (100%)                              20 (100%)    10 (100%)    
      Dilatation                                                                 3 (30%)      1 (10%)                               
      Cervix, Cyst                                                  1 (10%)                                                         
      Endometrium, Hyperplasia, Cystic                                                        1 (10%)                               
      Epithelium, Hyperplasia, Focal                                                          1 (10%)                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Lymph Node                                                                                (2)          (5)                       
      Iliac, Hyperplasia, Lymphoid                                                                         4 (80%)                  
      Mediastinal, Angiectasis                                                                1 (50%)                               
      Mediastinal, Hyperplasia, Lymphoid                                                      1 (50%)                               
      Mediastinal, Pigmentation                                                               1 (50%)                               
   Spleen                                             (10)         (10)         (10)         (10)         (20)         (10)         
      Congestion                                      10 (100%)    10 (100%)    10 (100%)     3 (30%)     17 (85%)     10 (100%)    
      Depletion Lymphoid                                                                                   8 (40%)     10 (100%)    
      Hematopoietic Cell Proliferation                                           1 (10%)      8 (80%)     15 (75%)                  
      Hyperplasia, Lymphoid                                                                                1 (5%)                   
      Hypertrophy                                                                1 (10%)                                            
      Pigmentation                                    10 (100%)    10 (100%)    10 (100%)     7 (70%)      8 (40%)     10 (100%)    
      Capsule, Hypertrophy                            10 (100%)    10 (100%)     8 (80%)      9 (90%)     20 (100%)    10 (100%)    
      Capsule, Inflammation, Chronic                   6 (60%)      2 (20%)                   1 (10%)     17 (85%)      9 (90%)     
____________________________________________________________________________________________________________________________________
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    7                                                              
NTP Experiment-Test: 05092-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: SPECIAL STUDY                                     O-NITROANISOLE                                      Date: 04/08/97  
Route: DOSED FEED                                                                                                 Time: 13:45:49  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS FEMALE                   0.600%       0.600%       0.600%       0.600%       1.80%        1.80%           
                                                   3 SSAC       6 SSAC       9 SSAC       15 SSAC                   3 SSAC          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Lung                                                            (2)                                    (2)                       
      Infiltration Cellular, Multifocal, Lymphocyte                 2 (100%)                                                        
      Inflammation, Chronic, Multifocal                             2 (100%)                                                        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (10)         (10)         (10)         (10)         (20)         (10)         
      Hydronephrosis                                                                                      11 (55%)                  
      Nephropathy, Chronic                                                       3 (30%)      5 (50%)      2 (10%)                  
      Bilateral, Hydronephrosis                                                                            3 (15%)                  
      Corticomedullary Junction, Mineralization        9 (90%)                                                          9 (90%)     
      Papilla, Necrosis                                                                                    1 (5%)                   
      Pelvis, Dilatation                                                                                   2 (10%)                  
      Pelvis, Inflammation, Suppurative                                          1 (10%)                                            
      Pelvis, Mineralization                                                     1 (10%)      2 (20%)      8 (40%)                  
      Pelvis, Necrosis                                                                                     1 (5%)                   
      Proximal Convoluted Renal Tubule,                                                                                             
          Degeneration, Hyaline                                                               1 (10%)                               
      Renal Tubule, Mineralization                                  4 (40%)      8 (80%)      9 (90%)      9 (45%)                  
      Renal Tubule, Pigmentation                      10 (100%)    10 (100%)    10 (100%)    10 (100%)    20 (100%)    10 (100%)    
      Renal Tubule, Regeneration                                                 1 (10%)                   2 (10%)                  
      Transitional Epithelium, Hyperplasia                                       1 (10%)                   9 (45%)                  
   Ureter                                             (10)         (10)         (10)         (10)         (19)         (10)         
      Dilatation                                                                              1 (10%)     15 (79%)                  
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    8                                                              
NTP Experiment-Test: 05092-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: SPECIAL STUDY                                     O-NITROANISOLE                                      Date: 04/08/97  
Route: DOSED FEED                                                                                                 Time: 13:45:49  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS FEMALE                   0.600%       0.600%       0.600%       0.600%       1.80%        1.80%           
                                                   3 SSAC       6 SSAC       9 SSAC       15 SSAC                   3 SSAC          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
URINARY SYSTEM - CONT                                                                                                               
      Transitional Epithelium, Hyperplasia                                                                 2 (11%)                  
   Urinary Bladder                                    (10)         (10)         (9)          (10)         (20)         (10)         
      Hemorrhage                                                                                           2 (10%)                  
      Inflammation, Subacute                                        5 (50%)                                1 (5%)       8 (80%)     
      Inflammation, Suppurative                                                               1 (10%)      5 (25%)                  
      Metaplasia, Squamous                                                                    2 (20%)     13 (65%)     10 (100%)    
      Necrosis                                                                                1 (10%)      1 (5%)                   
      Transitional Epithelium, Hyperplasia             8 (80%)     10 (100%)     9 (100%)     3 (30%)      1 (5%)      10 (100%)    
      Transitional Epithelium, Metaplasia, Squamous                 1 (10%)                                                         
      Wall, Infiltration Cellular, Lipocyte                                                                2 (10%)                  
      Wall, Proliferation Connective Tissue                         2 (20%)      1 (11%)      6 (60%)     14 (70%)      6 (60%)     
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    9                                                              
NTP Experiment-Test: 05092-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: SPECIAL STUDY                                     O-NITROANISOLE                                      Date: 04/08/97  
Route: DOSED FEED                                                                                                 Time: 13:45:49  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS FEMALE                   1.80%        1.80%        1.80%                                                  
                                                   6 SSAC       9 SSAC       15 SSAC                                                
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially In Study                          10           10           10                                                  
  Scheduled Sacrifice                                 10            6                                                               
  Early Deaths                                                                                                                      
    Natural Death                                                   2            2                                                  
    Moribund Sacrifice                                              2            8                                                  
  Survivors                                                                                                                         
  Animals Examined Microscopically                    10           10           10                                                  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Intestine Large, Cecum                                          (3)          (9)                                                 
      Ulcer                                                                      1 (11%)                                            
   Intestine Large, Colon                                          (3)          (9)                                                 
      Autolysis                                                                  1 (11%)                                            
      Intussusception                                                            1 (11%)                                            
      Necrosis                                                                   1 (11%)                                            
      Parasite Metazoan                                             1 (33%)                                                         
      Proliferation Connective Tissue                                            1 (11%)                                            
      Epithelium, Hyperplasia                                       1 (33%)      3 (33%)                                            
   Intestine Large, Rectum                                         (3)          (9)                                                 
      Autolysis                                                                  1 (11%)                                            
   Liver                                              (10)         (10)         (10)                                                
      Hepatodiaphragmatic Nodule                                    1 (10%)      1 (10%)                                            
      Inflammation, Granulomatous, Multiple            5 (50%)     10 (100%)     9 (90%)                                            
      Hepatocyte, Hypertrophy                         10 (100%)                  1 (10%)                                            
      Hepatocyte, Necrosis, Multifocal                10 (100%)                                                                     
      Hepatocyte, Vacuolization Cytoplasmic            1 (10%)                                                                      
      Hepatocyte, Kupffer Cell, Pigmentation          10 (100%)    10 (100%)    10 (100%)                                           
   Pancreas                                                                     (1)                                                 
      Acinus, Atrophy                                                            1 (100%)                                           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   10                                                              
NTP Experiment-Test: 05092-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: SPECIAL STUDY                                     O-NITROANISOLE                                      Date: 04/08/97  
Route: DOSED FEED                                                                                                 Time: 13:45:49  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS FEMALE                   1.80%        1.80%        1.80%                                                  
                                                   6 SSAC       9 SSAC       15 SSAC                                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Uterus                                             (10)         (10)         (10)                                                
      Atrophy                                         10 (100%)     7 (70%)      4 (40%)                                            
      Dilatation                                                    1 (10%)      2 (20%)                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Lymph Node                                                      (3)          (5)                                                 
      Iliac, Hyperplasia, Lymphoid                                               3 (60%)                                            
      Mediastinal, Hyperplasia, Lymphoid                                         1 (20%)                                            
      Pancreatic, Hyperplasia, Lymphoid                             1 (33%)                                                         
   Lymph Node, Mesenteric                                                       (1)                                                 
      Angiectasis                                                                1 (100%)                                           
   Spleen                                             (10)         (10)         (10)                                                
      Atrophy                                                       1 (10%)                                                         
      Congestion                                      10 (100%)     6 (60%)      6 (60%)                                            
      Depletion Lymphoid                              10 (100%)     2 (20%)      6 (60%)                                            
      Hematopoietic Cell Proliferation                              6 (60%)      4 (40%)                                            
      Pigmentation                                     9 (90%)      7 (70%)      4 (40%)                                            
      Capsule, Hypertrophy                            10 (100%)    10 (100%)     9 (90%)                                            
      Capsule, Inflammation, Chronic                  10 (100%)    10 (100%)     9 (90%)                                            
   Thymus                                                          (2)                                                              
      Atrophy                                                       1 (50%)                                                         
      Congestion                                                    1 (50%)                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   11                                                              
NTP Experiment-Test: 05092-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: SPECIAL STUDY                                     O-NITROANISOLE                                      Date: 04/08/97  
Route: DOSED FEED                                                                                                 Time: 13:45:49  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS FEMALE                   1.80%        1.80%        1.80%                                                  
                                                   6 SSAC       9 SSAC       15 SSAC                                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                                          (1)                                                 
      Cornea, Edema                                                              1 (100%)                                           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (10)         (10)         (10)                                                
      Hydronephrosis                                                1 (10%)      3 (30%)                                            
      Nephropathy, Chronic                                          4 (40%)                                                         
      Corticomedullary Junction, Mineralization        2 (20%)                                                                      
      Papilla, Necrosis                                             1 (10%)                                                         
      Pelvis, Mineralization                                        3 (30%)      4 (40%)                                            
      Pelvis, Necrosis                                                           1 (10%)                                            
      Renal Tubule, Mineralization                                  7 (70%)      5 (50%)                                            
      Renal Tubule, Pigmentation                      10 (100%)    10 (100%)    10 (100%)                                           
      Renal Tubule, Regeneration                                                 1 (10%)                                            
      Transitional Epithelium, Hyperplasia             2 (20%)      3 (30%)      5 (50%)                                            
   Ureter                                             (10)         (10)         (10)                                                
      Dilatation                                                    3 (30%)      3 (30%)                                            
   Urinary Bladder                                    (10)         (10)         (10)                                                
      Hemorrhage                                                    1 (10%)      2 (20%)                                            
      Inflammation, Subacute                          10 (100%)     1 (10%)                                                         
      Inflammation, Suppurative                                     3 (30%)      2 (20%)                                            
      Metaplasia, Squamous                            10 (100%)     8 (80%)      8 (80%)                                            
      Wall, Proliferation Connective Tissue           10 (100%)     5 (50%)      5 (50%)                                            
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   12                                                              
NTP Experiment-Test: 05092-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: SPECIAL STUDY                                     O-NITROANISOLE                                      Date: 04/08/97  
Route: DOSED FEED                                                                                                 Time: 13:45:49  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     0.0%         0.0%         0.0%         0.0%         0.0%         0.600%          
                                                                 3 SSAC       6 SSAC       9 SSAC       15 SSAC                     
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially In Study                          20           10           10           10           10           20           
  Scheduled Sacrifice                                              10           10           10            9                        
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                 6                                                   1           19           
    Natural Death                                      1                                                                            
  Survivors                                                                                                                         
    Terminal Sacrifice                                13                                                                1           
  Animals Examined Microscopically                    20           10           10           10           10           20           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Intestine Large, Cecum                                                                                 (1)          (15)         
      Edema                                                                                                             2 (13%)     
      Parasite Metazoan                                                                                                 1 (7%)      
      Submucosa, Proliferation Connective Tissue                                                                        1 (7%)      
   Intestine Large, Colon                                                                                 (1)          (15)         
      Edema                                                                                                             1 (7%)      
      Fibrosis                                                                                                          1 (7%)      
      Hemorrhage                                                                                                        2 (13%)     
      Serosa, Inflammation, Chronic                                                                                     1 (7%)      
   Intestine Large, Rectum                                                                                (1)          (15)         
      Hemorrhage                                                                                                        1 (7%)      
   Liver                                              (20)         (10)         (10)         (10)         (10)         (20)         
      Basophilic Focus                                 1 (5%)                                 1 (10%)      3 (30%)      2 (10%)     
      Basophilic Focus, Multiple                       8 (40%)                                             1 (10%)      3 (15%)     
      Clear Cell Focus                                 1 (5%)                                              1 (10%)      1 (5%)      
      Clear Cell Focus, Multiple                       4 (20%)                                                                      
      Degeneration, Cystic                             1 (5%)                                                                       
      Eosinophilic Focus                               5 (25%)                                             1 (10%)      2 (10%)     
      Eosinophilic Focus, Multiple                     2 (10%)                                                          1 (5%)      
      Hematopoietic Cell Proliferation                              1 (10%)                                             2 (10%)     
      Hepatodiaphragmatic Nodule                       2 (10%)      2 (20%)                   1 (10%)                   1 (5%)      
      Hyperplasia, Nodular                             5 (25%)                                                                      
      Inflammation, Granulomatous, Multiple            4 (20%)                                3 (30%)      7 (70%)      6 (30%)     
      Mixed Cell Focus                                 1 (5%)                                                           1 (5%)      
      Mixed Cell Focus, Multiple                       1 (5%)                                                                       
      Necrosis, Focal                                               1 (10%)                                                         
      Thrombosis                                                                                                        1 (5%)      
      Vacuolization Cytoplasmic                        1 (5%)                                              4 (40%)      2 (10%)     
      Bile Duct, Hyperplasia                          20 (100%)                               6 (60%)      9 (90%)      7 (35%)     
      Centrilobular, Degeneration                                                                                       1 (5%)      
      Hepatocyte, Necrosis, Multiple                                1 (10%)                                             1 (5%)      
      Hepatocyte, Kupffer Cell, Pigmentation                                                                            1 (5%)      
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   13                                                              
NTP Experiment-Test: 05092-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: SPECIAL STUDY                                     O-NITROANISOLE                                      Date: 04/08/97  
Route: DOSED FEED                                                                                                 Time: 13:45:49  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     0.0%         0.0%         0.0%         0.0%         0.0%         0.600%          
                                                                 3 SSAC       6 SSAC       9 SSAC       15 SSAC                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Serosa, Fibrosis                                                                                                  1 (5%)      
   Mesentery                                          (2)                                    (1)          (2)          (2)          
      Thrombosis                                                                                                        1 (50%)     
      Fat, Necrosis, Focal                             2 (100%)                               1 (100%)     2 (100%)                 
   Pancreas                                           (1)                                                              (4)          
      Edema                                                                                                             1 (25%)     
      Polyarteritis                                    1 (100%)                                                                     
      Acinar Cell, Atrophy                                                                                              1 (25%)     
      Acinar Cell, Hyperplasia                                                                                          1 (25%)     
   Stomach, Forestomach                               (3)                                                 (1)          (9)          
      Abscess                                                                                                           2 (22%)     
      Edema                                                                                                             1 (11%)     
      Inflammation, Suppurative                        1 (33%)                                                                      
      Mineralization                                                                                                    1 (11%)     
      Ulcer                                            2 (67%)                                                                      
      Ulcer, Multiple                                  1 (33%)                                                                      
      Epithelium, Hyperplasia                          1 (33%)                                                          4 (44%)     
   Stomach, Glandular                                 (3)                                                 (1)          (9)          
      Erosion, Multiple                                1 (33%)                                                                      
      Mineralization                                                                                                    2 (22%)     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Blood Vessel                                                                                                        (1)          
      Aorta, Mineralization                                                                                             1 (100%)    
   Heart                                              (4)                                                 (2)          (2)          
      Inflammation, Chronic                            4 (100%)                                                         2 (100%)    
      Mineralization                                                                                                    1 (50%)     
      Atrium, Congestion                               1 (25%)                                             2 (100%)                 
      Atrium, Dilatation                               1 (25%)                                                                      
      Atrium, Thrombosis                               2 (50%)                                                          1 (50%)     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Gland, Cortex                              (2)                                                              (2)          
      Vacuolization Cytoplasmic                        1 (50%)                                                                      
      Vacuolization Cytoplasmic, Focal                                                                                  1 (50%)     
   Parathyroid Gland                                                                                                   (2)          
      Hyperplasia                                                                                                       2 (100%)    
____________________________________________________________________________________________________________________________________
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   14                                                              
NTP Experiment-Test: 05092-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: SPECIAL STUDY                                     O-NITROANISOLE                                      Date: 04/08/97  
Route: DOSED FEED                                                                                                 Time: 13:45:49  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     0.0%         0.0%         0.0%         0.0%         0.0%         0.600%          
                                                                 3 SSAC       6 SSAC       9 SSAC       15 SSAC                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Epididymis                                         (20)         (10)         (10)         (10)         (10)         (20)         
      Depletion Cellular                              17 (85%)                                                         12 (60%)     
   Preputial Gland                                    (6)                                    (1)                       (6)          
      Atrophy                                          2 (33%)                                                          3 (50%)     
      Hyperplasia                                                                                                       1 (17%)     
      Inflammation, Suppurative                        2 (33%)                                                                      
      Necrosis                                         1 (17%)                                                                      
      Duct, Cyst                                       2 (33%)                                                          4 (67%)     
      Duct, Cyst, Multiple                                                                                              1 (17%)     
   Prostate                                                                                                            (1)          
      Inflammation, Chronic                                                                                             1 (100%)    
   Seminal Vesicle                                    (2)                                                                           
      Atrophy                                          2 (100%)                                                                     
   Testes                                             (20)         (10)         (10)         (10)         (10)         (20)         
      Degeneration, Focal                                                        1 (10%)                                            
      Bilateral, Interstitial Cell, Hyperplasia                                                            2 (20%)                  
      Interstitial Cell, Hyperplasia                   2 (10%)                                             4 (40%)      9 (45%)     
      Seminiferous Tubule, Atrophy                    20 (100%)                                                        13 (65%)     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Lymph Node                                         (13)                                                (2)          (14)         
      Deep Cervical, Angiectasis                       1 (8%)                                                                       
      Iliac, Hyperplasia, Lymphoid                                                                                      1 (7%)      
      Mediastinal, Angiectasis                         2 (15%)                                                          3 (21%)     
      Mediastinal, Congestion                                                                                           1 (7%)      
      Mediastinal, Hemorrhage                          2 (15%)                                                                      
      Mediastinal, Pigmentation                                                                                         3 (21%)     
      Pancreatic, Angiectasis                          1 (8%)                                                           1 (7%)      
      Pancreatic, Edema                                                                                                 1 (7%)      
      Pancreatic, Hemorrhage                           1 (8%)                                                                       
      Pancreatic, Hyperplasia, Lymphoid                                                                    1 (50%)      1 (7%)      
      Renal, Angiectasis                               1 (8%)                                                           1 (7%)      
      Renal, Inflammation, Granulomatous                                                                                1 (7%)      
   Lymph Node, Mandibular                             (5)                                                 (1)          (7)          
      Hemorrhage                                       1 (20%)                                                                      
      Hyperplasia, Lymphoid                                                                                1 (100%)     3 (43%)     
   Lymph Node, Mesenteric                             (5)                                                 (1)          (8)          
      Angiectasis                                                                                                       2 (25%)     
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   15                                                              
NTP Experiment-Test: 05092-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: SPECIAL STUDY                                     O-NITROANISOLE                                      Date: 04/08/97  
Route: DOSED FEED                                                                                                 Time: 13:45:49  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     0.0%         0.0%         0.0%         0.0%         0.0%         0.600%          
                                                                 3 SSAC       6 SSAC       9 SSAC       15 SSAC                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
HEMATOPOIETIC SYSTEM - CONT                                                                                                         
      Congestion                                                                                                        1 (13%)     
      Cyst                                                                                                              2 (25%)     
      Edema                                                                                                             3 (38%)     
      Hemorrhage                                       1 (20%)                                                                      
      Hyperplasia, Lymphoid                            1 (20%)                                             1 (100%)                 
   Spleen                                             (20)         (10)         (10)         (10)         (10)         (20)         
      Congestion                                       5 (25%)                                             7 (70%)     11 (55%)     
      Depletion Lymphoid                               1 (5%)                                                                       
      Fibrosis                                         1 (5%)                                                           1 (5%)      
      Fibrosis, Focal                                  1 (5%)                                                                       
      Hematopoietic Cell Proliferation                 9 (45%)                                             4 (40%)     14 (70%)     
      Inflammation, Granulomatous                      1 (5%)                                                                       
      Pigmentation                                     5 (25%)     10 (100%)                 10 (100%)     7 (70%)     11 (55%)     
      Capsule, Hypertrophy                                                                                              9 (45%)     
      Capsule, Inflammation, Chronic                                                                                    1 (5%)      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (1)                                                              (1)          
      Duct, Cyst                                                                                                        1 (100%)    
   Skin                                               (2)                                                 (2)          (1)          
      Epidermis, Fibrosis, Focal                                                                           1 (50%)                  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (1)                                                              (1)          
      Calvarium, Hyperostosis                                                                                           1 (100%)    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (5)                                                                           
      Compression                                      2 (40%)                                                                      
      Hemorrhage, Multiple                             1 (20%)                                                                      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Lung                                               (7)                                                 (1)          (1)          
      Inflammation, Granulomatous                      1 (14%)                                                                      
      Alveolar Epithelium, Hyperplasia                 1 (14%)                                                                      
      Alveolus, Pigmentation                           1 (14%)                                                                      
   Nose                                               (1)                                                                           
      Lumen, Hyperkeratosis                            1 (100%)                                                                     
      Lumen, Inflammation, Suppurative                 1 (100%)                                                                     
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   16                                                              
NTP Experiment-Test: 05092-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: SPECIAL STUDY                                     O-NITROANISOLE                                      Date: 04/08/97  
Route: DOSED FEED                                                                                                 Time: 13:45:49  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     0.0%         0.0%         0.0%         0.0%         0.0%         0.600%          
                                                                 3 SSAC       6 SSAC       9 SSAC       15 SSAC                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                                                       (1)                                    
      Cataract                                                                                1 (100%)                              
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (20)         (10)         (10)         (10)         (10)         (20)         
      Nephropathy                                                   2 (20%)                                                         
      Nephropathy, Chronic                            20 (100%)     2 (20%)      4 (40%)     10 (100%)    10 (100%)    20 (100%)    
      Cortex, Cyst                                                                                                      1 (5%)      
      Pelvis, Inflammation, Suppurative                                                                    1 (10%)                  
      Pelvis, Mineralization                          16 (80%)                                4 (40%)      3 (30%)     20 (100%)    
      Renal Tubule, Hyperplasia                                                                                         1 (5%)      
      Renal Tubule, Pigmentation                      19 (95%)                   2 (20%)     10 (100%)    10 (100%)    20 (100%)    
      Transitional Epithelium, Hyperplasia             5 (25%)                                                         20 (100%)    
   Ureter                                             (18)         (9)          (10)         (10)         (10)         (20)         
      Dilatation                                                                              1 (10%)                   3 (15%)     
      Transitional Epithelium, Hyperplasia                                                                              1 (5%)      
   Urethra                                                                                                             (2)          
      Bulbourethral Gland, Cyst, Multiple                                                                               1 (50%)     
   Urinary Bladder                                    (20)         (9)          (10)         (10)         (10)         (20)         
      Hemorrhage                                                                                                        1 (5%)      
      Metaplasia, Squamous                                                                                              1 (5%)      
      Necrosis                                                                                                          1 (5%)      
      Transitional Epithelium, Hyperplasia                                                                              6 (30%)     
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   17                                                              
NTP Experiment-Test: 05092-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: SPECIAL STUDY                                     O-NITROANISOLE                                      Date: 04/08/97  
Route: DOSED FEED                                                                                                 Time: 13:45:49  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     0.600%       0.600%       0.600%       0.600%       1.80%        1.80%           
                                                   3 SSAC       6 SSAC       9 SSAC       15 SSAC                     3 SSAC        
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially In Study                          10           10           10           10           20           10           
  Scheduled Sacrifice                                 10           10           10            3                        10           
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                                                        7           14                        
    Natural Death                                                                                          6                        
  Survivors                                                                                                                         
  Animals Examined Microscopically                    10           10           10           10           20           10           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Intestine Large, Cecum                                                       (2)          (9)          (18)                      
      Dilatation                                                                                           1 (6%)                   
   Intestine Large, Colon                                                       (2)          (9)          (18)                      
      Hemorrhage                                                                                           2 (11%)                  
      Intussusception                                                                                      4 (22%)                  
      Parasite Metazoan                                                                                    1 (6%)                   
      Epithelium, Hyperplasia                                                                              4 (22%)                  
      Serosa, Inflammation, Chronic                                                                        1 (6%)                   
      Wall, Proliferation Connective Tissue                                                                1 (6%)                   
   Intestine Large, Rectum                                                      (2)          (9)          (18)                      
      Epithelium, Hyperplasia                                                                              1 (6%)                   
   Liver                                              (10)         (10)         (10)         (10)         (20)         (10)         
      Basophilic Focus                                                           1 (10%)                                            
      Eosinophilic Focus                                                                                   1 (5%)                   
      Hematopoietic Cell Proliferation                                                                     1 (5%)                   
      Hepatodiaphragmatic Nodule                                                              1 (10%)      1 (5%)                   
      Inflammation, Granulomatous, Multifocal                                    1 (10%)                                            
      Inflammation, Granulomatous, Multiple            1 (10%)                   9 (90%)      9 (90%)      8 (40%)                  
      Vacuolization Cytoplasmic                                                  3 (30%)                   1 (5%)                   
      Artery, Inflammation, Chronic, Focal                          1 (10%)                                                         
      Hepatocyte, Hypertrophy                                                                              2 (10%)     10 (100%)    
      Hepatocyte, Necrosis, Multifocal                              1 (10%)                                1 (5%)      10 (100%)    
      Hepatocyte, Vacuolization Cytoplasmic                         3 (30%)                                                         
      Hepatocyte, Vacuolization Cytoplasmic,                                                                                        
          Multifocal                                                                                                    3 (30%)     
      Hepatocyte, Kupffer Cell, Pigmentation                        3 (30%)                   1 (10%)     18 (90%)     10 (100%)    
   Stomach, Forestomach                                            (2)                       (1)          (5)                       
      Inflammation, Suppurative                                                                            1 (20%)                  
      Ulcer                                                                                                1 (20%)                  
      Epithelium, Hyperplasia                                                                              1 (20%)                  
____________________________________________________________________________________________________________________________________
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   18                                                              
NTP Experiment-Test: 05092-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: SPECIAL STUDY                                     O-NITROANISOLE                                      Date: 04/08/97  
Route: DOSED FEED                                                                                                 Time: 13:45:49  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     0.600%       0.600%       0.600%       0.600%       1.80%        1.80%           
                                                   3 SSAC       6 SSAC       9 SSAC       15 SSAC                     3 SSAC        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Epididymis                                         (10)         (10)         (10)         (10)         (20)         (10)         
      Depletion Cellular                                                                                   5 (25%)     10 (100%)    
   Preputial Gland                                                              (1)                                                 
      Hyperplasia                                                                1 (100%)                                           
   Prostate                                                                                  (3)          (1)                       
      Inflammation, Suppurative                                                               1 (33%)      1 (100%)                 
   Seminal Vesicle                                                                           (1)          (1)                       
      Adventitia, Edema                                                                       1 (100%)                              
   Testes                                             (10)         (10)         (10)         (10)         (20)         (10)         
      Atrophy                                                                                                           9 (90%)     
      Degeneration                                                                                                     10 (100%)    
      Edema                                                                                                             7 (70%)     
      Bilateral, Interstitial Cell, Hyperplasia                                               1 (10%)                               
      Interstitial Cell, Hyperplasia                                             2 (20%)      3 (30%)                               
      Seminiferous Tubule, Atrophy                                                                        15 (75%)                  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Lymph Node                                                                   (1)          (3)          (3)                       
      Bronchial, Hyperplasia, Lymphoid                                                                     1 (33%)                  
      Iliac, Angiectasis                                                                      1 (33%)                               
      Mediastinal, Hyperplasia, Lymphoid                                                                   2 (67%)                  
      Pancreatic, Hyperplasia                                                    1 (100%)                                           
      Renal, Angiectasis                                                                      1 (33%)                               
   Lymph Node, Mesenteric                                                                    (2)          (1)                       
      Cyst                                                                                    1 (50%)                               
      Fibrosis                                                                                             1 (100%)                 
      Hyperplasia, Lymphoid                                                                   1 (50%)                               
   Spleen                                             (10)         (10)         (10)         (10)         (20)         (10)         
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   19                                                              
NTP Experiment-Test: 05092-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: SPECIAL STUDY                                     O-NITROANISOLE                                      Date: 04/08/97  
Route: DOSED FEED                                                                                                 Time: 13:45:49  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     0.600%       0.600%       0.600%       0.600%       1.80%        1.80%           
                                                   3 SSAC       6 SSAC       9 SSAC       15 SSAC                     3 SSAC        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
HEMATOPOIETIC SYSTEM - CONT                                                                                                         
      Congestion                                       9 (90%)     10 (100%)    10 (100%)     5 (50%)     16 (80%)     10 (100%)    
      Depletion Lymphoid                                                                                  13 (65%)     10 (100%)    
      Fibrosis                                                                                             3 (15%)                  
      Hematopoietic Cell Proliferation                                           2 (20%)      7 (70%)      7 (35%)                  
      Hyperplasia, Lymphoid                                                                   2 (20%)                               
      Pigmentation                                    10 (100%)    10 (100%)    10 (100%)     5 (50%)     12 (60%)     10 (100%)    
      Capsule, Hypertrophy                            10 (100%)     7 (70%)      8 (80%)      8 (80%)     20 (100%)    10 (100%)    
      Capsule, Inflammation, Chronic                   1 (10%)                   2 (20%)      5 (50%)     20 (100%)    10 (100%)    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Lung                                                            (2)          (2)          (2)          (1)          (1)          
      Congestion                                                                              2 (100%)                              
      Infiltration Cellular, Multifocal, Lymphocyte                 2 (100%)     1 (50%)                   1 (100%)                 
      Inflammation                                                  1 (50%)                                                         
      Inflammation, Chronic                                         1 (50%)                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                                          (1)                                    (1)          
      Cornea, Edema                                                              1 (100%)                                           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (10)         (10)         (10)         (10)         (20)         (10)         
      Hydronephrosis                                                                                       5 (25%)                  
      Infarct                                                                                              3 (15%)                  
      Nephropathy, Chronic                            10 (100%)    10 (100%)    10 (100%)    10 (100%)    14 (70%)      7 (70%)     
      Pigmentation                                                  1 (10%)                                                         
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   20                                                              
NTP Experiment-Test: 05092-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: SPECIAL STUDY                                     O-NITROANISOLE                                      Date: 04/08/97  
Route: DOSED FEED                                                                                                 Time: 13:45:49  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     0.600%       0.600%       0.600%       0.600%       1.80%        1.80%           
                                                   3 SSAC       6 SSAC       9 SSAC       15 SSAC                     3 SSAC        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
URINARY SYSTEM - CONT                                                                                                               
      Bilateral, Hydronephrosis                                                               2 (20%)                               
      Papilla, Necrosis                                                                                    1 (5%)                   
      Pelvis, Dilatation                                                                      1 (10%)      1 (5%)                   
      Pelvis, Mineralization                           9 (90%)                  10 (100%)    10 (100%)    13 (65%)                  
      Renal Tubule, Degeneration                      10 (100%)                                                                     
      Renal Tubule, Dilatation                                                                             1 (5%)                   
      Renal Tubule, Mineralization                                 10 (100%)                  1 (10%)      2 (10%)                  
      Renal Tubule, Necrosis                          10 (100%)                                            1 (5%)                   
      Renal Tubule, Pigmentation                       9 (90%)      9 (90%)     10 (100%)     9 (90%)     20 (100%)    10 (100%)    
      Renal Tubule, Regeneration                                   10 (100%)                  3 (30%)      3 (15%)                  
      Transitional Epithelium, Hyperplasia                                       7 (70%)      7 (70%)     11 (55%)                  
   Ureter                                             (10)         (10)         (10)         (8)          (20)         (10)         
      Dilatation                                                                              2 (25%)      6 (30%)                  
   Urethra                                                                                                (1)                       
      Transitional Epithelium, Hyperplasia                                                                 1 (100%)                 
   Urinary Bladder                                    (9)          (10)         (10)         (10)         (20)         (10)         
      Hemorrhage                                                                                           3 (15%)                  
      Inflammation, Subacute                                                                                           10 (100%)    
      Inflammation, Suppurative                                                  1 (10%)                   3 (15%)                  
      Metaplasia, Squamous                                                                    2 (20%)     18 (90%)     10 (100%)    
      Transitional Epithelium, Hyperplasia                         10 (100%)     9 (90%)      4 (40%)      1 (5%)       9 (90%)     
      Wall, Proliferation Connective Tissue                         1 (10%)                   2 (20%)     15 (75%)     10 (100%)    
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   21                                                              
NTP Experiment-Test: 05092-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: SPECIAL STUDY                                     O-NITROANISOLE                                      Date: 04/08/97  
Route: DOSED FEED                                                                                                 Time: 13:45:49  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     1.80%        1.80%        1.80%                                                  
                                                     6 SSAC       9 SSAC      15 SSAC                                               
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially In Study                          10           10           10                                                  
  Scheduled Sacrifice                                 10            6                                                               
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                              3            6                                                  
    Natural Death                                                   1            4                                                  
  Survivors                                                                                                                         
  Animals Examined Microscopically                    10           10           10                                                  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Intestine Large, Cecum                             (3)          (5)          (9)                                                 
      Dilatation                                                                 1 (11%)                                            
   Intestine Large, Colon                             (3)          (5)          (9)                                                 
      Hemorrhage                                                                 2 (22%)                                            
      Intussusception                                                            2 (22%)                                            
      Necrosis                                                                   1 (11%)                                            
      Parasite Metazoan                                             1 (20%)                                                         
      Epithelium, Hyperplasia                          1 (33%)      1 (20%)      5 (56%)                                            
   Liver                                              (10)         (10)         (10)                                                
      Cyst                                                          1 (10%)                                                         
      Eosinophilic Focus, Multiple                                  1 (10%)                                                         
      Inflammation, Granulomatous, Multiple            1 (10%)      8 (80%)      5 (50%)                                            
      Hepatocyte, Hypertrophy                         10 (100%)     1 (10%)      3 (30%)                                            
      Hepatocyte, Necrosis, Multifocal                10 (100%)                                                                     
      Hepatocyte, Vacuolization Cytoplasmic            6 (60%)                                                                      
      Hepatocyte, Kupffer Cell, Pigmentation          10 (100%)     9 (90%)      8 (80%)                                            
   Stomach, Forestomach                                            (2)                                                              
      Epithelium, Hyperplasia                                       2 (100%)                                                        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   22                                                              
NTP Experiment-Test: 05092-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: SPECIAL STUDY                                     O-NITROANISOLE                                      Date: 04/08/97  
Route: DOSED FEED                                                                                                 Time: 13:45:49  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     1.80%        1.80%        1.80%                                                  
                                                     6 SSAC       9 SSAC      15 SSAC                                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Epididymis                                         (10)         (10)         (10)                                                
      Depletion Cellular                              10 (100%)     3 (30%)      2 (20%)                                            
   Prostate                                                                     (4)                                                 
      Inflammation, Suppurative                                                  2 (50%)                                            
      Proliferation Connective Tissue                                            1 (25%)                                            
      Epithelium, Hyperplasia                                                    1 (25%)                                            
   Seminal Vesicle                                                              (1)                                                 
      Epithelium, Hyperplasia                                                    1 (100%)                                           
   Testes                                             (10)         (10)         (10)                                                
      Atrophy                                         10 (100%)                                                                     
      Degeneration                                    10 (100%)                                                                     
      Seminiferous Tubule, Atrophy                                  5 (50%)      4 (40%)                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Lymph Node                                                                   (3)                                                 
      Iliac, Hyperplasia, Lymphoid                                               1 (33%)                                            
      Pancreatic, Hyperplasia, Lymphoid                                          2 (67%)                                            
   Spleen                                             (10)         (10)         (10)                                                
      Congestion                                      10 (100%)     6 (60%)      6 (60%)                                            
      Depletion Lymphoid                              10 (100%)     2 (20%)      5 (50%)                                            
      Fibrosis                                         2 (20%)                   1 (10%)                                            
      Hematopoietic Cell Proliferation                              6 (60%)      4 (40%)                                            
      Inflammation, Chronic                                                      1 (10%)                                            
      Pigmentation                                     8 (80%)      3 (30%)      5 (50%)                                            
      Thrombosis                                                    1 (10%)                                                         
      Capsule, Hypertrophy                            10 (100%)    10 (100%)    10 (100%)                                           
      Capsule, Inflammation, Chronic                  10 (100%)    10 (100%)     9 (90%)                                            
   Thymus                                                                       (2)                                                 
      Atrophy                                                                    2 (100%)                                           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   23                                                              
NTP Experiment-Test: 05092-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: SPECIAL STUDY                                     O-NITROANISOLE                                      Date: 04/08/97  
Route: DOSED FEED                                                                                                 Time: 13:45:49  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     1.80%        1.80%        1.80%                                                  
                                                     6 SSAC       9 SSAC      15 SSAC                                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (10)         (10)         (10)                                                
      Fibrosis                                                      1 (10%)                                                         
      Hydronephrosis                                                4 (40%)      3 (30%)                                            
      Nephropathy, Chronic                            10 (100%)     9 (90%)      7 (70%)                                            
      Pigmentation                                     1 (10%)                                                                      
      Bilateral, Hydronephrosis                                                  1 (10%)                                            
      Pelvis, Dilatation                                            1 (10%)                                                         
      Pelvis, Mineralization                           1 (10%)      2 (20%)      7 (70%)                                            
      Pelvis, Necrosis                                                           1 (10%)                                            
      Renal Tubule, Mineralization                     1 (10%)      1 (10%)                                                         
      Renal Tubule, Pigmentation                       9 (90%)     10 (100%)    10 (100%)                                           
      Renal Tubule, Regeneration                      10 (100%)     4 (40%)      1 (10%)                                            
      Transitional Epithelium, Hemorrhage                                        1 (10%)                                            
      Transitional Epithelium, Hyperplasia             5 (50%)      4 (40%)      7 (70%)                                            
   Ureter                                             (9)          (10)         (10)                                                
      Dilatation                                                    4 (40%)      5 (50%)                                            
      Hemorrhage                                                                 1 (10%)                                            
      Inflammation, Chronic                                                      1 (10%)                                            
      Transitional Epithelium, Hyperplasia             1 (11%)      1 (10%)                                                         
   Urinary Bladder                                    (10)         (10)         (10)                                                
      Cyst, Multiple                                   1 (10%)                                                                      
      Hemorrhage                                                    2 (20%)      1 (10%)                                            
      Inflammation, Subacute                           7 (70%)      3 (30%)                                                         
      Inflammation, Suppurative                                     3 (30%)                                                         
      Metaplasia, Squamous                            10 (100%)     6 (60%)     10 (100%)                                           
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   24                                                              
NTP Experiment-Test: 05092-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: SPECIAL STUDY                                     O-NITROANISOLE                                      Date: 04/08/97  
Route: DOSED FEED                                                                                                 Time: 13:45:49  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     1.80%        1.80%        1.80%                                                  
                                                     6 SSAC       9 SSAC      15 SSAC                                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
URINARY SYSTEM - CONT                                                                                                               
      Transitional Epithelium, Hyperplasia                                       1 (10%)                                            
      Wall, Proliferation Connective Tissue            9 (90%)      7 (70%)      6 (60%)                                            
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   25                                                              
                             ------------------------------------------------------------                                           
                             ----------              END OF REPORT             ----------                                           
                             ------------------------------------------------------------