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TDMS Study 05203-08 Pathology Tables

NTP Experiment-Test: 05203-08         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                           O-NITROTOLUENE                                      Date: 11/16/00
Route: DOSED FEED                                                                                                 Time: 09:23:03

                                                   RATS, FINAL#1; CORE STUDY




       Facility:  Southern Research Institute

       Chemical CAS #:  88-72-2

       Lock Date:  12/10/98

       Cage Range:  All

       Reasons For Removal:    25022 Accidently Killed                 25019 Moribund Sacrifice
                               25020 Natural Death                     25021 Terminal Sacrifice

       Removal Date Range:     All

       Treatment Groups:       Include 002    0 PPM
                               Include 004    625 PPM
                               Include 006    1250 PPM
                               Include 008    2000 PPM
                               Include 001    0 PPM
                               Include 003    625 PPM
                               Include 005    1250 PPM
                               Include 007    2000 PPM


























a  Number of animals examined microscopically at site and number of animals with lesion

                                                              Page   1


NTP Experiment-Test: 05203-08         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                           O-NITROTOLUENE                                      Date: 11/16/00    
Route: DOSED FEED                                                                                                 Time: 09:23:03    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS FEMALE                   0 PPM        625 PPM      1250 PPM     2000 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
DISPOSITION SUMMARY                                                                                                                 
                                                                                                                                    
  Animals Initially In Study                          60           60           60           60                                     
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                10           11           19           22                                     
    Natural Death                                      3            2            2            5                                     
  Survivors                                                                                                                         
    Terminal Sacrifice                                45           46           39           33                                     
    Moribund Sacrifice                                 1            1                                                               
    Natural Death                                      1                                                                            
                                                                                                                                    
  Animals Examined Microscopically                    60           60           60           60                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Intestine Large, Colon                             (58)         (59)         (60)         (59)                                   
      Crypt, Diverticulum                              1 (2%)                                                                       
   Intestine Large, Rectum                            (60)         (60)         (60)         (58)                                   
      Fibrosis                                                                   1 (2%)                                             
   Intestine Large, Cecum                             (58)         (59)         (60)         (59)                                   
      Edema                                                         1 (2%)       1 (2%)                                             
   Liver                                              (60)         (59)         (60)         (60)                                   
      Angiectasis                                      2 (3%)       3 (5%)       4 (7%)       4 (7%)                                
      Basophilic Focus                                51 (85%)     56 (95%)     60 (100%)    54 (90%)                               
      Clear Cell Focus                                16 (27%)     30 (51%)     28 (47%)     33 (55%)                               
      Degeneration, Cystic                                                       1 (2%)       2 (3%)                                
      Eosinophilic Focus                               5 (8%)      12 (20%)     25 (42%)     32 (53%)                               
      Hematopoietic Cell Proliferation                              2 (3%)       1 (2%)       3 (5%)                                
      Hemorrhage                                                    1 (2%)       1 (2%)                                             
      Hepatodiaphragmatic Nodule                       9 (15%)     13 (22%)     10 (17%)      7 (12%)                               
      Infiltration Cellular, Mixed Cell               15 (25%)     11 (19%)      6 (10%)     12 (20%)                               
      Mixed Cell Focus                                 6 (10%)      9 (15%)     11 (18%)     28 (47%)                               
      Necrosis, Focal                                               1 (2%)       3 (5%)       5 (8%)                                
      Regeneration, Diffuse                                                                   1 (2%)                                
      Regeneration, Focal                              1 (2%)       2 (3%)                                                          
      Bile Duct, Hyperplasia                           7 (12%)      2 (3%)                                                          
      Centrilobular, Necrosis                          3 (5%)                    2 (3%)       2 (3%)                                
      Hepatocyte, Vacuolization Cytoplasmic            4 (7%)       2 (3%)       1 (2%)                                             
      Kupffer Cell, Pigmentation                       3 (5%)                                                                       
   Mesentery                                          (9)          (1)          (3)          (3)                                    
      Accessory Spleen                                 2 (22%)                   1 (33%)      1 (33%)                               
      Fat, Necrosis                                    7 (78%)      1 (100%)     2 (67%)                                            
   Pancreas                                           (60)         (59)         (60)         (60)                                   
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page    2                                                              
                                                                                                                                   
NTP Experiment-Test: 05203-08         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                           O-NITROTOLUENE                                      Date: 11/16/00    
Route: DOSED FEED                                                                                                 Time: 09:23:03    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS FEMALE                   0 PPM        625 PPM      1250 PPM     2000 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Atrophy                                         13 (22%)     10 (17%)      7 (12%)      4 (7%)                                
      Acinus, Hyperplasia, Focal                       1 (2%)       1 (2%)       2 (3%)       2 (3%)                                
   Salivary Glands                                    (60)         (60)         (60)         (60)                                   
      Atrophy                                          2 (3%)       3 (5%)       9 (15%)     48 (80%)                               
   Stomach, Forestomach                               (59)         (59)         (60)         (60)                                   
      Erosion                                          1 (2%)                    1 (2%)                                             
      Perforation                                                   1 (2%)                                                          
      Ulcer                                            1 (2%)       1 (2%)                    1 (2%)                                
      Epithelium, Hyperplasia                          5 (8%)       3 (5%)       1 (2%)                                             
   Stomach, Glandular                                 (60)         (59)         (60)         (60)                                   
      Erosion                                          1 (2%)       1 (2%)       1 (2%)       3 (5%)                                
      Ulcer                                            2 (3%)                    1 (2%)       1 (2%)                                
   Tooth                                              (2)                                                                           
      Inflammation, Chronic                            1 (50%)                                                                      
      Malformation                                     2 (100%)                                                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Heart                                              (60)         (60)         (60)         (60)                                   
      Cardiomyopathy                                  22 (37%)     16 (27%)     13 (22%)     13 (22%)                               
      Thrombosis                                                                 1 (2%)                                             
      Myocardium, Fibrosis                             1 (2%)       1 (2%)                    1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (60)         (60)         (60)         (59)                                   
      Accessory Adrenal Cortical Nodule                8 (13%)     10 (17%)      8 (13%)     10 (17%)                               
      Degeneration, Fatty                             13 (22%)     11 (18%)     17 (28%)     11 (19%)                               
      Hyperplasia, Diffuse                             3 (5%)       1 (2%)                    1 (2%)                                
      Hyperplasia, Focal                               9 (15%)      6 (10%)     14 (23%)     15 (25%)                               
      Hypertrophy, Focal                               6 (10%)      7 (12%)      6 (10%)      7 (12%)                               
      Necrosis                                         1 (2%)                                                                       
   Adrenal Medulla                                    (60)         (60)         (60)         (58)                                   
      Hyperplasia                                      8 (13%)      2 (3%)       3 (5%)       3 (5%)                                
   Pituitary Gland                                    (59)         (60)         (60)         (60)                                   
      Pars Distalis, Angiectasis                       6 (10%)      5 (8%)       4 (7%)       4 (7%)                                
      Pars Distalis, Cyst                             22 (37%)     20 (33%)     22 (37%)     24 (40%)                               
      Pars Distalis, Hyperplasia, Focal               12 (20%)      6 (10%)     12 (20%)      9 (15%)                               
      Pars Intermedia, Angiectasis                                  2 (3%)       1 (2%)                                             
      Pars Intermedia, Cyst                            3 (5%)       1 (2%)       1 (2%)       1 (2%)                                
   Thyroid Gland                                      (60)         (60)         (60)         (60)                                   
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page    3                                                              
                                                                                                                                   
NTP Experiment-Test: 05203-08         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                           O-NITROTOLUENE                                      Date: 11/16/00    
Route: DOSED FEED                                                                                                 Time: 09:23:03    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS FEMALE                   0 PPM        625 PPM      1250 PPM     2000 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ENDOCRINE SYSTEM - CONT                                                                                                             
      Ultimobranchial Cyst                             1 (2%)       1 (2%)       1 (2%)                                             
      C-Cell, Hyperplasia                             22 (37%)     24 (40%)     22 (37%)      9 (15%)                               
      Follicle, Cyst                                                2 (3%)       1 (2%)       1 (2%)                                
      Follicular Cell, Hyperplasia                                  1 (2%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Clitoral Gland                                     (59)         (57)         (54)         (53)                                   
      Atrophy                                          1 (2%)       3 (5%)       6 (11%)     25 (47%)                               
      Cyst                                             2 (3%)       4 (7%)       4 (7%)       2 (4%)                                
      Hyperplasia                                      5 (8%)       1 (2%)       4 (7%)       1 (2%)                                
      Inflammation, Chronic                            4 (7%)       4 (7%)       6 (11%)      5 (9%)                                
   Ovary                                              (60)         (59)         (60)         (60)                                   
      Angiectasis                                                                             2 (3%)                                
      Cyst                                             9 (15%)      8 (14%)     11 (18%)      6 (10%)                               
   Uterus                                             (60)         (59)         (60)         (60)                                   
      Angiectasis                                      1 (2%)                                                                       
      Cyst                                                                                    1 (2%)                                
      Hydrometra                                       7 (12%)      6 (10%)      1 (2%)       3 (5%)                                
      Hyperplasia, Cystic                              8 (13%)      6 (10%)      9 (15%)      8 (13%)                               
      Inflammation, Chronic                            2 (3%)       1 (2%)       1 (2%)                                             
      Epithelium, Hyperplasia                                                                 1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (60)         (60)         (60)         (60)                                   
      Hyperplasia                                      2 (3%)       7 (12%)     15 (25%)     24 (40%)                               
      Infiltration Cellular, Histiocyte                2 (3%)       1 (2%)       1 (2%)                                             
      Myelofibrosis                                    1 (2%)                                 2 (3%)                                
   Lymph Node                                         (8)          (4)          (4)          (4)                                    
      Mediastinal, Hemorrhage                          1 (13%)      1 (25%)      1 (25%)      3 (75%)                               
      Mediastinal, Pigmentation                        6 (75%)      1 (25%)      1 (25%)      3 (75%)                               
      Renal, Hemorrhage                                                                       1 (25%)                               
      Renal, Pigmentation                                                                     1 (25%)                               
   Lymph Node, Mandibular                             (60)         (60)         (59)         (59)                                   
      Ectasia                                          1 (2%)       3 (5%)                    4 (7%)                                
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page    4                                                              
                                                                                                                                   
NTP Experiment-Test: 05203-08         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                           O-NITROTOLUENE                                      Date: 11/16/00    
Route: DOSED FEED                                                                                                 Time: 09:23:03    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS FEMALE                   0 PPM        625 PPM      1250 PPM     2000 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
HEMATOPOIETIC SYSTEM - CONT                                                                                                         
      Hemorrhage                                       4 (7%)       4 (7%)       1 (2%)       4 (7%)                                
      Hyperplasia, Lymphoid                            3 (5%)       5 (8%)       6 (10%)     15 (25%)                               
      Pigmentation                                    31 (52%)     33 (55%)     30 (51%)     30 (51%)                               
   Lymph Node, Mesenteric                             (59)         (58)         (59)         (59)                                   
      Hemorrhage                                       5 (8%)       3 (5%)       4 (7%)       5 (8%)                                
      Hyperplasia, Lymphoid                                                                   1 (2%)                                
      Pigmentation                                                  4 (7%)       1 (2%)       3 (5%)                                
   Spleen                                             (60)         (59)         (60)         (59)                                   
      Congestion                                                    1 (2%)                                                          
      Fibrosis                                         1 (2%)                    1 (2%)                                             
      Hematopoietic Cell Proliferation                22 (37%)     38 (64%)     48 (80%)     48 (81%)                               
      Necrosis                                         2 (3%)                                                                       
      Pigmentation                                    36 (60%)     44 (75%)     43 (72%)     46 (78%)                               
      Lymphoid Follicle, Atrophy                                    1 (2%)                    1 (2%)                                
   Thymus                                             (57)         (55)         (58)         (58)                                   
      Cyst                                             1 (2%)                    2 (3%)       2 (3%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (60)         (60)         (59)         (60)                                   
      Dilatation                                      40 (67%)     30 (50%)     29 (49%)     24 (40%)                               
      Galactocele                                                   1 (2%)                                                          
      Hyperplasia                                     14 (23%)     36 (60%)     30 (51%)     19 (32%)                               
   Skin                                               (59)         (60)         (60)         (60)                                   
      Angiectasis                                                                1 (2%)                                             
      Ulcer                                            1 (2%)                                                                       
      Subcutaneous Tissue, Edema                                                 1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (60)         (60)         (60)         (60)                                   
      Cranium, Osteopetrosis                           2 (3%)       6 (10%)      6 (10%)     10 (17%)                               
      Femur, Osteopetrosis                             8 (13%)      9 (15%)     13 (22%)     16 (27%)                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (60)         (60)         (60)         (60)                                   
      Compression                                      6 (10%)     10 (17%)      5 (8%)       3 (5%)                                
      Hydrocephalus                                    2 (3%)       4 (7%)                    3 (5%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page    5                                                              
                                                                                                                                   
NTP Experiment-Test: 05203-08         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                           O-NITROTOLUENE                                      Date: 11/16/00    
Route: DOSED FEED                                                                                                 Time: 09:23:03    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS FEMALE                   0 PPM        625 PPM      1250 PPM     2000 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Lung                                               (60)         (60)         (60)         (60)                                   
      Hemorrhage                                       2 (3%)       2 (3%)       2 (3%)       1 (2%)                                
      Infiltration Cellular, Histiocyte               52 (87%)     54 (90%)     53 (88%)     55 (92%)                               
      Alveolar Epithelium, Hyperplasia                 6 (10%)     14 (23%)     16 (27%)      9 (15%)                               
      Alveolar Epithelium, Hyperplasia, Atypical                                              1 (2%)                                
   Nose                                               (60)         (60)         (60)         (60)                                   
      Foreign Body                                     2 (3%)                                 7 (12%)                               
      Inflammation, Chronic                            2 (3%)       1 (2%)       2 (3%)       8 (13%)                               
      Respiratory Epithelium, Hyperplasia              2 (3%)                                 3 (5%)                                
      Respiratory Epithelium, Metaplasia, Squamous                               1 (2%)       1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                (3)          (3)          (2)          (1)                                    
      Cataract                                         1 (33%)      2 (67%)      1 (50%)      1 (100%)                              
      Hemorrhage                                       1 (33%)                                                                      
      Inflammation, Chronic                            1 (33%)      1 (33%)                                                         
      Retina, Degeneration                             2 (67%)      2 (67%)      1 (50%)      1 (100%)                              
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (60)         (59)         (60)         (60)                                   
      Cyst                                                          1 (2%)       1 (2%)                                             
      Hydronephrosis                                                             1 (2%)                                             
      Infarct                                          2 (3%)                    1 (2%)                                             
      Inflammation, Chronic                            2 (3%)       1 (2%)       1 (2%)       1 (2%)                                
      Nephropathy                                     53 (88%)     45 (76%)     48 (80%)     52 (87%)                               
      Renal Tubule, Cytoplasmic Alteration                          1 (2%)       1 (2%)                                             
      Renal Tubule, Degeneration, Hyaline              9 (15%)     10 (17%)      4 (7%)      11 (18%)                               
      Renal Tubule, Necrosis                           2 (3%)                                                                       
      Renal Tubule, Pigmentation                       9 (15%)     10 (17%)      7 (12%)     17 (28%)                               
      Transitional Epithelium, Hyperplasia             1 (2%)                    1 (2%)       1 (2%)                                
   Urinary Bladder                                    (60)         (59)         (60)         (60)                                   
      Transitional Epithelium, Hyperplasia                                       1 (2%)                                             
                                                                                                                                    
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page    6                                                              
                                                                                                                                   
NTP Experiment-Test: 05203-08         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                           O-NITROTOLUENE                                      Date: 11/16/00    
Route: DOSED FEED                                                                                                 Time: 09:23:03    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS MALE                     0 PPM        625 PPM      1250 PPM     2000 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
DISPOSITION SUMMARY                                                                                                                 
                                                                                                                                    
  Animals Initially In Study                          70           60           60           60                                     
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                18           35           48           53                                     
    Natural Death                                      3            7            6            7                                     
    Accidently Killed                                                            3                                                  
  Survivors                                                                                                                         
    Terminal Sacrifice                                38           18            3                                                  
    Natural Death                                      1                                                                            
                                                                                                                                    
  Animals Examined Microscopically                    60           60           60           60                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Intestine Large, Cecum                             (60)         (60)         (60)         (58)                                   
      Edema                                            1 (2%)                                                                       
   Liver                                              (60)         (60)         (60)         (60)                                   
      Angiectasis                                                   1 (2%)       2 (3%)       2 (3%)                                
      Atrophy                                          1 (2%)       1 (2%)       1 (2%)       4 (7%)                                
      Basophilic Focus                                38 (63%)     22 (37%)     21 (35%)     25 (42%)                               
      Clear Cell Focus                                29 (48%)     29 (48%)     34 (57%)     31 (52%)                               
      Cyst                                                                                    1 (2%)                                
      Degeneration, Cystic                             3 (5%)       3 (5%)       1 (2%)       2 (3%)                                
      Eosinophilic Focus                               7 (12%)     18 (30%)     29 (48%)     24 (40%)                               
      Fibrosis                                                      1 (2%)                                                          
      Hematopoietic Cell Proliferation                              6 (10%)      2 (3%)       2 (3%)                                
      Hemorrhage                                       2 (3%)                    2 (3%)       2 (3%)                                
      Hepatodiaphragmatic Nodule                       5 (8%)       8 (13%)      8 (13%)      5 (8%)                                
      Infiltration Cellular, Mixed Cell                1 (2%)       5 (8%)      11 (18%)     20 (33%)                               
      Mixed Cell Focus                                 5 (8%)       7 (12%)     12 (20%)      6 (10%)                               
      Necrosis, Focal                                  3 (5%)       4 (7%)       6 (10%)      6 (10%)                               
      Bile Duct, Hyperplasia                          53 (88%)     37 (62%)      7 (12%)                                            
      Centrilobular, Necrosis                          1 (2%)       3 (5%)       8 (13%)      5 (8%)                                
      Hepatocyte, Vacuolization Cytoplasmic            4 (7%)       2 (3%)       1 (2%)       1 (2%)                                
      Kupffer Cell, Pigmentation                       4 (7%)                    1 (2%)       3 (5%)                                
   Mesentery                                          (16)         (6)          (5)          (4)                                    
      Accessory Spleen                                 3 (19%)                                3 (75%)                               
      Congestion                                       3 (19%)                                                                      
      Hemorrhage                                                    1 (17%)                                                         
      Fat, Necrosis                                   13 (81%)      3 (50%)      5 (100%)     1 (25%)                               
   Oral Mucosa                                                                  (1)          (1)                                    
      Hyperplasia                                                                1 (100%)                                           
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page    7                                                              
                                                                                                                                   
NTP Experiment-Test: 05203-08         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                           O-NITROTOLUENE                                      Date: 11/16/00    
Route: DOSED FEED                                                                                                 Time: 09:23:03    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS MALE                     0 PPM        625 PPM      1250 PPM     2000 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
   Pancreas                                           (60)         (60)         (60)         (60)                                   
      Atrophy                                         11 (18%)     14 (23%)      7 (12%)      4 (7%)                                
      Acinus, Hyperplasia, Focal                       1 (2%)       2 (3%)       3 (5%)       4 (7%)                                
   Salivary Glands                                    (60)         (60)         (59)         (60)                                   
      Atrophy                                                       2 (3%)      18 (31%)     43 (72%)                               
   Stomach, Forestomach                               (59)         (60)         (60)         (60)                                   
      Edema                                            4 (7%)       2 (3%)                    1 (2%)                                
      Ulcer                                            2 (3%)       2 (3%)       1 (2%)       1 (2%)                                
      Epithelium, Hyperplasia                          6 (10%)      2 (3%)       1 (2%)       2 (3%)                                
   Stomach, Glandular                                 (59)         (60)         (60)         (60)                                   
      Edema                                                                                   1 (2%)                                
      Erosion                                          4 (7%)       2 (3%)       7 (12%)      7 (12%)                               
      Infiltration Cellular, Lymphoid                  1 (2%)                                                                       
      Ulcer                                            1 (2%)       2 (3%)                    3 (5%)                                
   Tongue                                             (1)                       (1)                                                 
      Epithelium, Hyperplasia                          1 (100%)                                                                     
   Tooth                                                                                     (1)                                    
      Malformation                                                                            1 (100%)                              
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Heart                                              (60)         (60)         (60)         (60)                                   
      Cardiomyopathy                                  40 (67%)     43 (72%)     43 (72%)     37 (62%)                               
      Thrombosis                                       1 (2%)       1 (2%)       1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (60)         (60)         (60)         (60)                                   
      Accessory Adrenal Cortical Nodule               13 (22%)     12 (20%)     13 (22%)     10 (17%)                               
      Degeneration, Fatty                             16 (27%)     10 (17%)     11 (18%)      4 (7%)                                
      Hyperplasia, Diffuse                                                       1 (2%)       3 (5%)                                
      Hyperplasia, Focal                               6 (10%)      2 (3%)       6 (10%)      3 (5%)                                
      Hypertrophy, Focal                               3 (5%)       2 (3%)       2 (3%)                                             
   Adrenal Medulla                                    (60)         (60)         (60)         (59)                                   
      Hyperplasia                                      7 (12%)      4 (7%)       2 (3%)                                             
   Islets, Pancreatic                                 (60)         (60)         (60)         (60)                                   
      Hyperplasia                                      2 (3%)                                 2 (3%)                                
      Pigmentation                                     1 (2%)                                 2 (3%)                                
   Parathyroid Gland                                  (58)         (55)         (59)         (58)                                   
      Hyperplasia                                                   1 (2%)                                                          
   Pituitary Gland                                    (59)         (60)         (58)         (59)                                   
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page    8                                                              
                                                                                                                                   
NTP Experiment-Test: 05203-08         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                           O-NITROTOLUENE                                      Date: 11/16/00    
Route: DOSED FEED                                                                                                 Time: 09:23:03    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS MALE                     0 PPM        625 PPM      1250 PPM     2000 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ENDOCRINE SYSTEM - CONT                                                                                                             
      Pars Distalis, Angiectasis                       3 (5%)                    7 (12%)      2 (3%)                                
      Pars Distalis, Cyst                              2 (3%)       6 (10%)      3 (5%)       4 (7%)                                
      Pars Distalis, Cytoplasmic Alteration            1 (2%)                    1 (2%)       4 (7%)                                
      Pars Distalis, Hyperplasia, Focal               10 (17%)     13 (22%)     13 (22%)     10 (17%)                               
      Pars Intermedia, Cyst                                         1 (2%)       1 (2%)                                             
   Thyroid Gland                                      (59)         (60)         (60)         (60)                                   
      Ultimobranchial Cyst                                          1 (2%)       2 (3%)       3 (5%)                                
      C-Cell, Hyperplasia                             10 (17%)     11 (18%)      9 (15%)      7 (12%)                               
      Follicle, Cyst                                   3 (5%)       2 (3%)                                                          
      Follicular Cell, Hyperplasia                     1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   Peritoneum                                         (3)          (21)         (33)         (46)                                   
      Mesothelium, Hyperplasia                         1 (33%)      1 (5%)       4 (12%)      2 (4%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Epididymis                                         (60)         (60)         (59)         (60)                                   
      Atypia Cellular                                 39 (65%)     32 (53%)     27 (46%)     21 (35%)                               
      Fibrosis                                                      2 (3%)                                                          
      Inflammation, Chronic                                         1 (2%)                                                          
   Preputial Gland                                    (60)         (59)         (58)         (56)                                   
      Atrophy                                          7 (12%)      9 (15%)     35 (60%)     41 (73%)                               
      Cyst                                             1 (2%)       4 (7%)       1 (2%)                                             
      Hyperplasia                                                   1 (2%)                                                          
      Inflammation, Chronic                           40 (67%)     43 (73%)     36 (62%)     27 (48%)                               
   Prostate                                           (60)         (59)         (60)         (60)                                   
      Inflammation, Chronic                           24 (40%)     14 (24%)     18 (30%)      9 (15%)                               
      Ventral, Hyperplasia                            18 (30%)      3 (5%)       9 (15%)      1 (2%)                                
   Testes                                             (60)         (60)         (60)         (60)                                   
      Angiectasis                                                                             2 (3%)                                
      Germinal Epithelium, Atrophy                    13 (22%)     21 (35%)     12 (20%)     19 (32%)                               
      Interstitial Cell, Hyperplasia                  10 (17%)     14 (23%)     13 (22%)     31 (52%)                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (60)         (60)         (60)         (60)                                   
      Hyperplasia                                      2 (3%)      25 (42%)     43 (72%)     45 (75%)                               
   Lymph Node                                         (16)         (14)         (4)          (9)                                    
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page    9                                                              
                                                                                                                                   
NTP Experiment-Test: 05203-08         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                           O-NITROTOLUENE                                      Date: 11/16/00    
Route: DOSED FEED                                                                                                 Time: 09:23:03    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS MALE                     0 PPM        625 PPM      1250 PPM     2000 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
HEMATOPOIETIC SYSTEM - CONT                                                                                                         
      Iliac, Hyperplasia, Lymphoid                                                            1 (11%)                               
      Mediastinal, Atrophy                                                                    1 (11%)                               
      Mediastinal, Hemorrhage                          2 (13%)      3 (21%)      1 (25%)      2 (22%)                               
      Mediastinal, Pigmentation                        6 (38%)      9 (64%)      3 (75%)      8 (89%)                               
      Pancreatic, Pigmentation                         1 (6%)       1 (7%)                                                          
      Renal, Ectasia                                                             1 (25%)                                            
      Renal, Pigmentation                              1 (6%)                    1 (25%)                                            
   Lymph Node, Mandibular                             (58)         (59)         (58)         (59)                                   
      Atrophy                                                                                 1 (2%)                                
      Ectasia                                          2 (3%)                                                                       
      Hemorrhage                                       2 (3%)       2 (3%)       1 (2%)       1 (2%)                                
      Hyperplasia, Lymphoid                            3 (5%)       4 (7%)       3 (5%)       2 (3%)                                
      Pigmentation                                     9 (16%)      2 (3%)       6 (10%)     12 (20%)                               
   Lymph Node, Mesenteric                             (60)         (60)         (59)         (58)                                   
      Atrophy                                          1 (2%)                    2 (3%)       1 (2%)                                
      Hemorrhage                                       2 (3%)       6 (10%)      3 (5%)       2 (3%)                                
      Pigmentation                                     3 (5%)       3 (5%)                                                          
   Spleen                                             (60)         (60)         (60)         (60)                                   
      Fibrosis                                         6 (10%)      6 (10%)      9 (15%)      7 (12%)                               
      Hematopoietic Cell Proliferation                 7 (12%)     33 (55%)     38 (63%)     47 (78%)                               
      Hemorrhage                                                    2 (3%)                                                          
      Pigmentation                                     9 (15%)      8 (13%)     13 (22%)     16 (27%)                               
      Capsule, Fibrosis                                                                       1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (57)         (47)         (46)         (43)                                   
      Dilatation                                       3 (5%)      10 (21%)      1 (2%)       1 (2%)                                
      Galactocele                                      2 (4%)                                                                       
      Hyperplasia                                      6 (11%)      2 (4%)       2 (4%)       2 (5%)                                
   Skin                                               (60)         (60)         (60)         (60)                                   
      Cyst                                                          1 (2%)                                                          
      Inflammation, Chronic                            1 (2%)                    1 (2%)                                             
      Subcutaneous Tissue, Edema                                                 1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (60)         (60)         (60)         (60)                                   
      Cranium, Osteopetrosis                                        1 (2%)                    2 (3%)                                
   Skeletal Muscle                                    (1)          (5)          (3)                                                 
      Atrophy                                          1 (100%)                                                                     
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page   10                                                              
                                                                                                                                   
NTP Experiment-Test: 05203-08         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                           O-NITROTOLUENE                                      Date: 11/16/00    
Route: DOSED FEED                                                                                                 Time: 09:23:03    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS MALE                     0 PPM        625 PPM      1250 PPM     2000 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
MUSCULOSKELETAL SYSTEM - CONT                                                                                                       
      Hemorrhage                                                    1 (20%)                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (60)         (60)         (60)         (60)                                   
      Compression                                      6 (10%)      3 (5%)       2 (3%)       1 (2%)                                
      Developmental Malformation                                                              1 (2%)                                
      Gliosis                                                       1 (2%)                                                          
      Hemorrhage                                       1 (2%)                                                                       
      Hydrocephalus                                    3 (5%)       1 (2%)       1 (2%)       2 (3%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Lung                                               (60)         (60)         (60)         (60)                                   
      Congestion                                                    1 (2%)                                                          
      Hemorrhage                                       3 (5%)                    1 (2%)                                             
      Infiltration Cellular, Histiocyte               25 (42%)     42 (70%)     40 (67%)     22 (37%)                               
      Metaplasia, Osseous                              1 (2%)       1 (2%)       1 (2%)                                             
      Alveolar Epithelium, Hyperplasia                 2 (3%)       8 (13%)      3 (5%)       7 (12%)                               
   Nose                                               (60)         (60)         (60)         (60)                                   
      Foreign Body                                     9 (15%)     13 (22%)     10 (17%)     11 (18%)                               
      Inflammation, Chronic                            9 (15%)      9 (15%)      8 (13%)      9 (15%)                               
      Inflammation, Suppurative                                                  2 (3%)                                             
      Respiratory Epithelium, Hyperplasia              6 (10%)      5 (8%)       7 (12%)      8 (13%)                               
      Respiratory Epithelium, Metaplasia, Squamous     2 (3%)       1 (2%)       1 (2%)       1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                (2)          (1)          (2)          (1)                                    
      Atrophy                                          1 (50%)                                                                      
      Cataract                                                      1 (100%)     1 (50%)      1 (100%)                              
      Inflammation, Chronic                            1 (50%)                                                                      
      Retina, Degeneration                             1 (50%)      1 (100%)     1 (50%)      1 (100%)                              
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (60)         (60)         (60)         (60)                                   
      Cyst                                                          1 (2%)       3 (5%)       2 (3%)                                
      Infarct                                                                                 1 (2%)                                
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page   11                                                              
                                                                                                                                   
NTP Experiment-Test: 05203-08         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                           O-NITROTOLUENE                                      Date: 11/16/00    
Route: DOSED FEED                                                                                                 Time: 09:23:03    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS MALE                     0 PPM        625 PPM      1250 PPM     2000 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
URINARY SYSTEM - CONT                                                                                                               
      Inflammation, Chronic                                         1 (2%)                                                          
      Mineralization                                                             1 (2%)                                             
      Nephropathy                                     56 (93%)     59 (98%)     56 (93%)     56 (93%)                               
      Renal Tubule, Degeneration, Hyaline              3 (5%)       3 (5%)                    1 (2%)                                
      Renal Tubule, Dilatation                         1 (2%)       3 (5%)                    2 (3%)                                
      Renal Tubule, Necrosis                                        1 (2%)       1 (2%)                                             
      Renal Tubule, Pigmentation                       5 (8%)      12 (20%)     14 (23%)      9 (15%)                               
      Transitional Epithelium, Hyperplasia             1 (2%)                    1 (2%)                                             
   Urinary Bladder                                    (60)         (60)         (60)         (59)                                   
      Fibrosis                                                                   1 (2%)       2 (3%)                                
      Inflammation, Chronic                                                      2 (3%)                                             
      Transitional Epithelium, Hyperplasia                          2 (3%)       2 (3%)       3 (5%)                                
      Transitional Epithelium, Inflammation,                                                                                        
          Chronic                                                                             1 (2%)                                
                                                                                                                                    
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page   12                                                              
                                                                                                                                   
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                             ----------              END OF REPORT             ----------                                           
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