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TDMS Study 05165-01 Pathology Tables

NTP Experiment-Test: 05165-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                  4,4 THIOBIS-(6-T-BUTYL-M-CRESOL)                             Date: 11/09/95
Route: DOSED FEED                                                                                                 Time: 19:42:26




       Facility:  Battelle Columbus Laboratory

       Chemical CAS #:  96-69-5

       Lock Date:  12/26/91

       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: 05165-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                  4,4 THIOBIS-(6-T-BUTYL-M-CRESOL)                             Date: 11/09/95  
Route: DOSED FEED                                                                                                 Time: 19:42:26  
____________________________________________________________________________________________________________________________________

         FISCHER 344 RATS FEMALE                   0 PPM        0 PPM        500 PPM      500 PPM      1000 PPM     1000 PPM        
                                                                 65 PATH                   65 PATH                   65 PATH        
____________________________________________________________________________________________________________________________________

DISPOSITION SUMMARY                                                                                                                 

  Animals Initially In Study                          50           10           50           10           50           10           

  Scheduled Sacrifice                                              10                        10                        10           
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                11                        14                        16                        
    Natural Death                                      5                         5                         2                        
  Survivors                                                                                                                         
    Terminal Sacrifice                                34                        30                        32                        
    Natural Death                                                                1                                                  

  Animals Examined Microscopically                    50           10           50           10           50           10           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Intestine Large, Colon                             (50)         (10)         (50)         (10)         (50)         (10)         
      Parasite Metazoan                                4 (8%)                    4 (8%)                    2 (4%)                   
   Intestine Large, Rectum                            (50)         (10)         (50)         (10)         (50)         (10)         
      Parasite Metazoan                                5 (10%)                   4 (8%)       3 (30%)      3 (6%)       2 (20%)     
   Intestine Large, Cecum                             (50)         (10)         (50)         (10)         (50)         (10)         
      Inflammation, Chronic Active                                               1 (2%)                                             
   Intestine Small, Jejunum                           (50)         (10)         (50)         (10)         (50)         (10)         
      Inflammation, Chronic Active                     1 (2%)                                                                       
   Liver                                              (50)         (10)         (50)         (10)         (50)         (10)         
      Angiectasis                                      1 (2%)                                                                       
      Basophilic Focus                                37 (74%)     10 (100%)    34 (68%)     10 (100%)    38 (76%)     10 (100%)    
      Clear Cell Focus                                                           1 (2%)                    1 (2%)                   
      Eosinophilic Focus                               5 (10%)                   7 (14%)                   8 (16%)      1 (10%)     
      Fatty Change                                     9 (18%)                   8 (16%)                  15 (30%)                  
      Fibrosis                                                                   1 (2%)                                             
      Hepatodiaphragmatic Nodule                      10 (20%)      2 (20%)      4 (8%)       1 (10%)      7 (14%)      6 (60%)     
      Inflammation, Chronic                           22 (44%)      2 (20%)     21 (42%)      6 (60%)     18 (36%)      2 (20%)     
      Mixed Cell Focus                                 5 (10%)                   4 (8%)       1 (10%)     14 (28%)                  
      Necrosis, Coagulative                                                      1 (2%)                                             
      Bile Duct, Hyperplasia                          18 (36%)      1 (10%)     18 (36%)      3 (30%)     21 (42%)      1 (10%)     
      Hepatocyte, Vacuolization Cytoplasmic           12 (24%)                  10 (20%)      1 (10%)     20 (40%)      1 (10%)     
      Periportal, Kupffer Cell, Hypertrophy           11 (22%)      1 (10%)     10 (20%)                   9 (18%)      5 (50%)     
      Sinusoid, Dilatation                                                       1 (2%)                                             
      Sinusoid, Ectasia                                                                                                 1 (10%)     
   Mesentery                                          (9)          (1)          (7)          (2)          (8)                       
      Ectopic Tissue                                                                                       1 (13%)                  
      Inflammation, Chronic Active                                  1 (100%)     2 (29%)      2 (100%)                              
      Inflammation, Necrotizing                        9 (100%)                  4 (57%)                   6 (75%)                  
      Mineralization                                   5 (56%)                                             1 (13%)                  
   Pancreas                                           (50)         (10)         (50)         (10)         (50)         (10)         
      Acinus, Atrophy                                 22 (44%)      4 (40%)     18 (36%)      5 (50%)     17 (34%)      4 (40%)     

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

                                                             Page    2                                                              
NTP Experiment-Test: 05165-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                  4,4 THIOBIS-(6-T-BUTYL-M-CRESOL)                             Date: 11/09/95  
Route: DOSED FEED                                                                                                 Time: 19:42:26  
____________________________________________________________________________________________________________________________________

         FISCHER 344 RATS FEMALE                   0 PPM        0 PPM        500 PPM      500 PPM      1000 PPM     1000 PPM        
                                                                 65 PATH                   65 PATH                   65 PATH        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
   Stomach, Forestomach                               (50)         (10)         (50)         (10)         (50)         (10)         
      Acanthosis                                       1 (2%)                    3 (6%)                    4 (8%)                   
      Hyperkeratosis                                   1 (2%)                    1 (2%)                    1 (2%)                   
      Inflammation, Chronic Active                     1 (2%)                    2 (4%)                    2 (4%)                   
   Stomach, Glandular                                 (50)         (10)         (50)         (10)         (50)         (10)         
      Erosion                                          3 (6%)                    2 (4%)                    1 (2%)                   
      Inflammation, Chronic Active                     1 (2%)                                                                       
      Mineralization                                                                                       1 (2%)                   
   Tooth                                              (2)                                                 (1)                       
      Gingiva, Inflammation, Chronic Active            1 (50%)                                             1 (100%)                 
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Heart                                              (50)         (10)         (50)         (10)         (50)         (10)         
      Cardiomyopathy, Chronic                         41 (82%)      7 (70%)     37 (74%)      9 (90%)     41 (82%)      5 (50%)     
      Mineralization                                                                                       1 (2%)                   
      Thrombosis                                       1 (2%)                                                                       
      Coronary Artery, Necrosis, Fibrinoid                                                                 1 (2%)                   
      Coronary Artery, Perivascular, Inflammation,                                                                                  
           Chronic Active                                                                                  1 (2%)                   
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (50)         (10)         (50)         (10)         (50)         (10)         
      Degeneration, Fatty                             20 (40%)      1 (10%)     20 (40%)                  14 (28%)                  
      Hematocyst                                                                                           1 (2%)                   
      Hyperplasia                                     11 (22%)      1 (10%)     16 (32%)                  12 (24%)                  
      Hypertrophy                                      2 (4%)                    2 (4%)                    1 (2%)                   
      Necrosis, Coagulative                                                      1 (2%)                                             
   Adrenal Medulla                                    (50)         (10)         (50)         (10)         (49)         (10)         
      Hyperplasia                                     10 (20%)                   7 (14%)                   2 (4%)                   
   Islets, Pancreatic                                 (50)         (10)         (50)         (10)         (50)         (10)         
      Hyperplasia                                      1 (2%)                                                                       
   Parathyroid Gland                                  (48)         (10)         (48)         (10)         (46)         (10)         
      Hyperplasia                                      1 (2%)                                              1 (2%)                   
   Pituitary Gland                                    (49)         (10)         (50)         (10)         (50)         (10)         
      Pars Distalis, Cyst                             24 (49%)      8 (80%)     29 (58%)      9 (90%)     22 (44%)      6 (60%)     
      Pars Distalis, Hyperplasia                      17 (35%)      7 (70%)     19 (38%)      5 (50%)     18 (36%)      6 (60%)     
      Pars Intermedia, Cyst                            3 (6%)                    1 (2%)                                             
      Rathke's Cleft, Inflammation, Chronic Active                  1 (10%)                                                         
      Rathke's Cleft, Pigmentation, Hemosiderin                     1 (10%)                                                         
   Thyroid Gland                                      (49)         (10)         (49)         (10)         (50)         (10)         
      Infiltration Cellular, Lymphocyte                1 (2%)                                                                       
      C-Cell, Hyperplasia                             28 (57%)      4 (40%)     24 (49%)      1 (10%)     27 (54%)      1 (10%)     
      Follicular Cell, Hyperplasia                     2 (4%)                    1 (2%)                    1 (2%)                   

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

                                                             Page    3                                                              
NTP Experiment-Test: 05165-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                  4,4 THIOBIS-(6-T-BUTYL-M-CRESOL)                             Date: 11/09/95  
Route: DOSED FEED                                                                                                 Time: 19:42:26  
____________________________________________________________________________________________________________________________________

         FISCHER 344 RATS FEMALE                   0 PPM        0 PPM        500 PPM      500 PPM      1000 PPM     1000 PPM        
                                                                 65 PATH                   65 PATH                   65 PATH        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Clitoral Gland                                     (49)         (10)         (48)         (10)         (50)         (10)         
      Hyperplasia                                      5 (10%)                   6 (13%)                  11 (22%)                  
      Inflammation, Chronic Active                     7 (14%)      2 (20%)      8 (17%)      5 (50%)      7 (14%)      1 (10%)     
      Duct, Dilatation                                 5 (10%)                   1 (2%)                                             
   Ovary                                              (50)         (10)         (50)         (10)         (50)         (10)         
      Atrophy                                                                                              1 (2%)                   
      Cyst                                            14 (28%)      2 (20%)     10 (20%)      3 (30%)     12 (24%)      4 (40%)     
      Necrosis, Coagulative                                                      1 (2%)                                             
   Uterus                                             (50)         (10)         (50)         (10)         (50)         (10)         
      Dilatation                                       3 (6%)                    3 (6%)                    2 (4%)                   
      Diverticulum                                                               1 (2%)                    1 (2%)                   
      Hemorrhage                                       1 (2%)                    1 (2%)                    1 (2%)                   
      Hyperplasia, Cystic, Glandular                   3 (6%)                    5 (10%)                   5 (10%)                  
      Inflammation, Chronic Active                                               3 (6%)                    2 (4%)                   
   Vagina                                                                                                 (2)                       
      Exudate                                                                                              1 (50%)                  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (49)         (10)         (50)         (10)         (50)         (10)         
      Femoral, Myelofibrosis                           1 (2%)                    1 (2%)                    1 (2%)                   
   Lymph Node                                         (14)                      (10)                      (10)                      
      Mediastinal, Cyst                                1 (7%)                                                                       
   Lymph Node, Mandibular                             (49)         (10)         (49)         (10)         (50)         (10)         
      Cyst                                                                                                 1 (2%)                   
      Hyperplasia, Plasma Cell                                                                             1 (2%)                   
      Sinus, Ectasia                                                1 (10%)                                                         
   Spleen                                             (50)         (10)         (50)         (10)         (50)         (10)         
      Fibrosis                                                                   2 (4%)                    2 (4%)                   
      Hematopoietic Cell Proliferation                 1 (2%)                    3 (6%)                    1 (2%)                   
      Necrosis, Coagulative                            1 (2%)                                                                       
      Red Pulp, Atrophy                                2 (4%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    

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

                                                             Page    4                                                              
NTP Experiment-Test: 05165-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                  4,4 THIOBIS-(6-T-BUTYL-M-CRESOL)                             Date: 11/09/95  
Route: DOSED FEED                                                                                                 Time: 19:42:26  
____________________________________________________________________________________________________________________________________

         FISCHER 344 RATS FEMALE                   0 PPM        0 PPM        500 PPM      500 PPM      1000 PPM     1000 PPM        
                                                                 65 PATH                   65 PATH                   65 PATH        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (50)         (10)         (50)         (10)         (50)         (10)         
      Hyperplasia, Cystic                             41 (82%)     10 (100%)    48 (96%)     10 (100%)    47 (94%)     10 (100%)    
      Inflammation, Chronic Active                     1 (2%)                                              1 (2%)                   
   Skin                                               (50)         (10)         (50)         (10)         (50)         (10)         
      Acanthosis                                                                 1 (2%)                                             
      Cyst Epithelial Inclusion                        3 (6%)                                                                       
      Hyperkeratosis                                                             1 (2%)                                             
      Inflammation, Chronic Active                     1 (2%)                    1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (49)         (10)         (50)         (10)         (50)         (10)         
      Cranium, Hyperostosis                                                                                1 (2%)                   
      Femur, Osteopetrosis                                                                                 1 (2%)                   
   Skeletal Muscle                                    (50)         (10)         (50)         (10)         (50)         (10)         
      Inflammation, Chronic Active                                                                         1 (2%)                   
      Necrosis, Coagulative                            2 (4%)       3 (30%)      3 (6%)       1 (10%)      3 (6%)       3 (30%)     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (50)         (10)         (50)         (10)         (50)         (10)         
      Compression                                      5 (10%)                   4 (8%)                    2 (4%)                   
      Hemorrhage, Acute                                2 (4%)                    2 (4%)                                             
      Hydrocephalus                                    4 (8%)                    4 (8%)                    2 (4%)                   
      Perivascular, Infiltration Cellular,                                                                                          
          Lymphocyte                                   1 (2%)                                                                       
   Spinal Cord                                                                                            (1)                       
      Compression                                                                                          1 (100%)                 
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Lung                                               (50)         (10)         (49)         (10)         (49)         (10)         
      Inflammation, Chronic Active                    12 (24%)      7 (70%)     12 (24%)      6 (60%)     12 (24%)      3 (30%)     
      Metaplasia, Osseous                              1 (2%)                                                                       
      Alveolar Epithelium, Hyperplasia                 5 (10%)      1 (10%)      4 (8%)                    3 (6%)                   
      Alveolus, Infiltration Cellular, Histiocyte     33 (66%)                  20 (41%)                  26 (53%)                  
      Artery, Mediastinum, Necrosis, Fibrinoid                                                             1 (2%)                   
      Artery, Mediastinum, Perivascular,                                                                                            
          Inflammation, Chronic Active                                                                     1 (2%)                   
   Nose                                               (50)         (10)         (50)         (10)         (50)         (10)         
      Fungus                                                                                               1 (2%)                   
      Inflammation, Chronic Active                     1 (2%)       1 (10%)      1 (2%)                    5 (10%)                  
      Nasolacrimal Duct, Inflammation, Suppurative    12 (24%)      3 (30%)     11 (22%)                  15 (30%)      2 (20%)     

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

                                                             Page    5                                                              
NTP Experiment-Test: 05165-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                  4,4 THIOBIS-(6-T-BUTYL-M-CRESOL)                             Date: 11/09/95  
Route: DOSED FEED                                                                                                 Time: 19:42:26  
____________________________________________________________________________________________________________________________________

         FISCHER 344 RATS FEMALE                   0 PPM        0 PPM        500 PPM      500 PPM      1000 PPM     1000 PPM        
                                                                 65 PATH                   65 PATH                   65 PATH        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
RESPIRATORY SYSTEM - CONT                                                                                                           
   Trachea                                            (50)         (10)         (50)         (10)         (50)         (10)         
      Cyst                                                                       1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                (2)          (2)          (3)                       (1)          (1)          
      Lens, Cataract                                   2 (100%)     2 (100%)     3 (100%)                  1 (100%)     1 (100%)    
      Retina, Atrophy                                  2 (100%)     2 (100%)     3 (100%)                  1 (100%)     1 (100%)    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (50)         (10)         (50)         (10)         (50)         (10)         
      Cyst                                                                                                 2 (4%)                   
      Hydronephrosis                                                             1 (2%)                                             
      Infarct, Chronic                                                           1 (2%)                                             
      Mineralization                                   1 (2%)      10 (100%)     2 (4%)      10 (100%)     1 (2%)      10 (100%)    
      Nephropathy, Chronic                            44 (88%)      9 (90%)     41 (82%)     10 (100%)    46 (92%)     10 (100%)    
      Renal Tubule, Epithelium, Hypertrophy            1 (2%)                                                                       
   Urinary Bladder                                    (50)         (10)         (49)         (10)         (50)         (10)         
      Transitional Epithelium, Hyperplasia             1 (2%)                                                                       
                                                                                                                                    

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

                                                             Page    6                                                              
NTP Experiment-Test: 05165-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                  4,4 THIOBIS-(6-T-BUTYL-M-CRESOL)                             Date: 11/09/95  
Route: DOSED FEED                                                                                                 Time: 19:42:26  
____________________________________________________________________________________________________________________________________

         FISCHER 344 RATS FEMALE                   2500 PPM     2500 PPM                                                            
                                                                 65 PATH                                                            
____________________________________________________________________________________________________________________________________

DISPOSITION SUMMARY                                                                                                                 

  Animals Initially In Study                          50           10                                                               

  Scheduled Sacrifice                                              10                                                               
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                16                                                                            
    Natural Death                                      6                                                                            
  Survivors                                                                                                                         
    Terminal Sacrifice                                28                                                                            

  Animals Examined Microscopically                    50           10                                                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Intestine Large, Rectum                            (50)         (10)                                                             
      Parasite Metazoan                                1 (2%)                                                                       
   Liver                                              (50)         (10)                                                             
      Basophilic Focus                                36 (72%)     10 (100%)                                                        
      Clear Cell Focus                                 1 (2%)                                                                       
      Eosinophilic Focus                               4 (8%)                                                                       
      Fatty Change                                    19 (38%)                                                                      
      Hepatodiaphragmatic Nodule                       8 (16%)                                                                      
      Inflammation, Chronic                           21 (42%)      4 (40%)                                                         
      Mixed Cell Focus                                34 (68%)     10 (100%)                                                        
      Bile Duct, Hyperplasia                          20 (40%)      3 (30%)                                                         
      Hepatocyte, Degeneration, Cystic                 4 (8%)                                                                       
      Hepatocyte, Vacuolization Cytoplasmic           34 (68%)      8 (80%)                                                         
      Periportal, Kupffer Cell, Hypertrophy           42 (84%)     10 (100%)                                                        
      Sinusoid, Dilatation                             1 (2%)                                                                       
   Mesentery                                          (4)                                                                           
      Inflammation, Necrotizing                        2 (50%)                                                                      
      Mineralization                                   1 (25%)                                                                      
   Pancreas                                           (49)         (10)                                                             
      Acinus, Atrophy                                 23 (47%)      3 (30%)                                                         
   Salivary Glands                                    (50)         (10)                                                             
      Atrophy                                          1 (2%)                                                                       
   Stomach, Forestomach                               (49)         (10)                                                             
      Acanthosis                                       1 (2%)                                                                       
      Diverticulum                                     1 (2%)                                                                       
      Inflammation, Chronic Active                     1 (2%)                                                                       
   Stomach, Glandular                                 (49)         (10)                                                             
      Diverticulum                                     2 (4%)                                                                       
      Inflammation, Chronic Active                     1 (2%)                                                                       
   Tongue                                             (1)                                                                           
      Epithelium, Acanthosis                           1 (100%)                                                                     
____________________________________________________________________________________________________________________________________

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

                                                             Page    7                                                              
NTP Experiment-Test: 05165-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                  4,4 THIOBIS-(6-T-BUTYL-M-CRESOL)                             Date: 11/09/95  
Route: DOSED FEED                                                                                                 Time: 19:42:26  
____________________________________________________________________________________________________________________________________

         FISCHER 344 RATS FEMALE                   2500 PPM     2500 PPM                                                            
                                                                 65 PATH                                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Heart                                              (50)         (10)                                                             
      Cardiomyopathy, Chronic                         39 (78%)      6 (60%)                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (50)         (10)                                                             
      Degeneration, Fatty                             15 (30%)      1 (10%)                                                         
      Hyperplasia                                     10 (20%)      1 (10%)                                                         
      Hypertrophy                                      1 (2%)                                                                       
      Necrosis, Coagulative                            1 (2%)                                                                       
   Adrenal Medulla                                    (50)         (10)                                                             
      Hyperplasia                                      7 (14%)                                                                      
   Parathyroid Gland                                  (50)         (10)                                                             
      Hyperplasia                                      1 (2%)                                                                       
   Pituitary Gland                                    (49)         (10)                                                             
      Craniopharyngeal Duct, Cyst                      1 (2%)                                                                       
      Pars Distalis, Cyst                             22 (45%)      5 (50%)                                                         
      Pars Distalis, Hyperplasia                      22 (45%)      3 (30%)                                                         
   Thyroid Gland                                      (50)         (10)                                                             
      C-Cell, Hyperplasia                             18 (36%)      1 (10%)                                                         
      Follicular Cell, Hyperplasia                     1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Clitoral Gland                                     (49)         (10)                                                             
      Hyperplasia                                      5 (10%)                                                                      
      Inflammation, Chronic Active                     2 (4%)       2 (20%)                                                         
      Duct, Dilatation                                 2 (4%)                                                                       
   Ovary                                              (50)         (10)                                                             
      Atrophy                                          1 (2%)                                                                       
      Cyst                                            16 (32%)      2 (20%)                                                         
   Uterus                                             (50)         (10)                                                             
      Dilatation                                       2 (4%)                                                                       
      Diverticulum                                     2 (4%)                                                                       
      Hemorrhage                                       1 (2%)                                                                       
      Hyperplasia, Cystic, Glandular                   1 (2%)                                                                       
      Inflammation, Chronic Active                     2 (4%)                                                                       
      Inflammation, Suppurative                                     1 (10%)                                                         

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

                                                             Page    8                                                              
NTP Experiment-Test: 05165-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                  4,4 THIOBIS-(6-T-BUTYL-M-CRESOL)                             Date: 11/09/95  
Route: DOSED FEED                                                                                                 Time: 19:42:26  
____________________________________________________________________________________________________________________________________

         FISCHER 344 RATS FEMALE                   2500 PPM     2500 PPM                                                            
                                                                 65 PATH                                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
GENITAL SYSTEM - CONT                                                                                                               
   Vagina                                             (3)                                                                           
      Estrus                                           1 (33%)                                                                      
      Exudate                                          1 (33%)                                                                      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (50)         (10)                                                             
      Femoral, Myelofibrosis                           2 (4%)                                                                       
   Lymph Node, Mandibular                             (50)         (10)                                                             
      Sinus, Ectasia                                                2 (20%)                                                         
   Spleen                                             (50)         (10)                                                             
      Fibrosis                                         1 (2%)                                                                       
      Hematopoietic Cell Proliferation                 1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (50)         (10)                                                             
      Hyperplasia, Cystic                             45 (90%)     10 (100%)                                                        
   Skin                                               (50)         (10)                                                             
      Acanthosis                                       2 (4%)                                                                       
      Inflammation, Chronic Active                     2 (4%)                                                                       
      Ulcer, Multiple                                  2 (4%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Skeletal Muscle                                    (50)         (10)                                                             
      Inflammation, Chronic Active                     1 (2%)                                                                       
      Necrosis, Coagulative                            3 (6%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (50)         (10)                                                             
      Compression                                      1 (2%)                                                                       
      Hemorrhage, Acute                                2 (4%)                                                                       
      Hydrocephalus                                    1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Lung                                               (50)         (10)                                                             
      Hemorrhage, Acute                                1 (2%)                                                                       
      Inflammation, Chronic Active                    19 (38%)      5 (50%)                                                         
      Leukocytosis                                     1 (2%)                                                                       

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

                                                             Page    9                                                              
NTP Experiment-Test: 05165-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                  4,4 THIOBIS-(6-T-BUTYL-M-CRESOL)                             Date: 11/09/95  
Route: DOSED FEED                                                                                                 Time: 19:42:26  
____________________________________________________________________________________________________________________________________

         FISCHER 344 RATS FEMALE                   2500 PPM     2500 PPM                                                            
                                                                 65 PATH                                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
RESPIRATORY SYSTEM - CONT                                                                                                           
      Metaplasia, Osseous                              1 (2%)                                                                       
      Alveolar Epithelium, Hyperplasia                 2 (4%)       1 (10%)                                                         
      Alveolus, Infiltration Cellular, Histiocyte     34 (68%)                                                                      
   Nose                                               (50)         (10)                                                             
      Fungus                                                        1 (10%)                                                         
      Inflammation, Chronic Active                     4 (8%)       1 (10%)                                                         
      Nasolacrimal Duct, Cyst                                       1 (10%)                                                         
      Nasolacrimal Duct, Inflammation, Suppurative     9 (18%)                                                                      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                (4)          (1)                                                              
      Cornea, Inflammation, Chronic Active             1 (25%)                                                                      
      Lens, Cataract                                   3 (75%)                                                                      
      Retina, Atrophy                                  3 (75%)                                                                      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (50)         (10)                                                             
      Cyst                                             2 (4%)                                                                       
      Mineralization                                                8 (80%)                                                         
      Necrosis, Coagulative                            1 (2%)                                                                       
      Nephropathy, Chronic                            48 (96%)     10 (100%)                                                        
                                                                                                                                    

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

                                                             Page   10                                                              
NTP Experiment-Test: 05165-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                  4,4 THIOBIS-(6-T-BUTYL-M-CRESOL)                             Date: 11/09/95  
Route: DOSED FEED                                                                                                 Time: 19:42:26  
____________________________________________________________________________________________________________________________________

         FISCHER 344 RATS MALE                      0 PPM       0 PPM        500 PPM      500 PPM      1000 PPM     1000 PPM        
                                                                 65 PATH                   65 PATH                   65 PATH        
____________________________________________________________________________________________________________________________________

DISPOSITION SUMMARY                                                                                                                 

  Animals Initially In Study                          50           10           50           10           50           10           

  Scheduled Sacrifice                                              10                        10                         7           
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                23                        14                        22            3           
    Natural Death                                      9                         8                         6                        
  Survivors                                                                                                                         
    Terminal Sacrifice                                18                        28                        22                        

  Animals Examined Microscopically                    50           10           50           10           50           10           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Intestine Large, Colon                             (50)         (10)         (50)         (10)         (50)         (10)         
      Parasite Metazoan                                                          2 (4%)                    2 (4%)                   
   Intestine Large, Rectum                            (50)         (10)         (50)         (10)         (50)         (10)         
      Inflammation, Chronic Active                                               2 (4%)                                             
      Parasite Metazoan                                5 (10%)      3 (30%)      1 (2%)       1 (10%)      2 (4%)       1 (10%)     
   Liver                                              (50)         (10)         (50)         (10)         (50)         (10)         
      Basophilic Focus                                18 (36%)      5 (50%)     22 (44%)      2 (20%)     23 (46%)      9 (90%)     
      Clear Cell Focus                                 2 (4%)                                              1 (2%)                   
      Eosinophilic Focus                               3 (6%)                    7 (14%)                   2 (4%)                   
      Fatty Change                                    15 (30%)                  14 (28%)                  13 (26%)                  
      Hematopoietic Cell Proliferation                                           1 (2%)                                             
      Hepatodiaphragmatic Nodule                       1 (2%)                    3 (6%)       2 (20%)      4 (8%)       2 (20%)     
      Inflammation, Chronic                            8 (16%)      1 (10%)      2 (4%)       1 (10%)      6 (12%)      1 (10%)     
      Mixed Cell Focus                                 6 (12%)      1 (10%)     14 (28%)      1 (10%)     18 (36%)      1 (10%)     
      Necrosis, Coagulative                            2 (4%)                    1 (2%)                    3 (6%)                   
      Thrombosis                                                                                           1 (2%)                   
      Bile Duct, Cyst                                                                         1 (10%)                               
      Bile Duct, Hyperplasia                          45 (90%)      9 (90%)     47 (94%)      9 (90%)     43 (86%)     10 (100%)    
      Hepatocyte, Degeneration, Cystic                10 (20%)                  14 (28%)                   9 (18%)                  
      Hepatocyte, Vacuolization Cytoplasmic           13 (26%)      1 (10%)     11 (22%)     10 (100%)    19 (38%)      7 (70%)     
      Periportal, Kupffer Cell, Hypertrophy            2 (4%)                    3 (6%)                    2 (4%)                   
   Mesentery                                          (11)         (2)          (7)          (1)          (10)         (1)          
      Ectopic Tissue                                                                                       1 (10%)                  
      Inflammation, Chronic Active                     2 (18%)      2 (100%)                  1 (100%)                  1 (100%)    
      Inflammation, Necrotizing                        6 (55%)                   4 (57%)                   7 (70%)                  
      Mineralization                                   2 (18%)                   1 (14%)                   1 (10%)                  
   Pancreas                                           (50)         (10)         (50)         (10)         (50)         (10)         
      Inflammation, Chronic Active                                                            1 (10%)                               
      Acinus, Atrophy                                 27 (54%)      5 (50%)     25 (50%)      4 (40%)     28 (56%)      3 (30%)     
      Artery, Inflammation, Chronic Active             1 (2%)                                              2 (4%)                   
      Artery, Necrosis, Fibrinoid                                                                          1 (2%)                   
   Stomach, Forestomach                               (50)         (10)         (50)         (10)         (50)         (10)         

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

                                                             Page   11                                                              
NTP Experiment-Test: 05165-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                  4,4 THIOBIS-(6-T-BUTYL-M-CRESOL)                             Date: 11/09/95  
Route: DOSED FEED                                                                                                 Time: 19:42:26  
____________________________________________________________________________________________________________________________________

         FISCHER 344 RATS MALE                      0 PPM       0 PPM        500 PPM      500 PPM      1000 PPM     1000 PPM        
                                                                 65 PATH                   65 PATH                   65 PATH        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Acanthosis                                       3 (6%)                    1 (2%)                    3 (6%)                   
      Inflammation, Chronic Active                     2 (4%)                    1 (2%)                                             
   Stomach, Glandular                                 (50)         (10)         (50)         (10)         (50)         (10)         
      Erosion                                                                    1 (2%)                    1 (2%)                   
      Inflammation, Chronic Active                     4 (8%)                    2 (4%)                    1 (2%)                   
      Mineralization                                                                                       1 (2%)                   
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Blood Vessel                                       (1)                                                                           
      Mesenteric Artery, Hemorrhage                    1 (100%)                                                                     
      Mesenteric Artery, Inflammation, Chronic                                                                                      
          Active                                       1 (100%)                                                                     
   Heart                                              (50)         (10)         (50)         (10)         (50)         (10)         
      Bacterium                                        1 (2%)                                                                       
      Cardiomyopathy, Chronic                         47 (94%)     10 (100%)    45 (90%)     10 (100%)    40 (80%)     10 (100%)    
      Metaplasia, Cartilagenous                                                  1 (2%)                                             
      Mineralization                                   1 (2%)                                                           1 (10%)     
      Thrombosis                                                                 6 (12%)                   4 (8%)                   
      Valve, Inflammation, Chronic Active              1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (50)         (10)         (50)         (10)         (50)         (10)         
      Accessory Adrenal Cortical Nodule                2 (4%)                                                                       
      Degeneration, Fatty                             19 (38%)      1 (10%)     15 (30%)      2 (20%)     15 (30%)      1 (10%)     
      Hematopoietic Cell Proliferation                                           1 (2%)                                             
      Hyperplasia                                     10 (20%)      1 (10%)      9 (18%)      1 (10%)      9 (18%)                  
      Hypertrophy                                      1 (2%)                    1 (2%)                                             
      Inflammation, Necrotizing                        1 (2%)                                                                       
      Necrosis, Coagulative                            2 (4%)                    1 (2%)                                             
   Adrenal Medulla                                    (50)         (10)         (50)         (10)         (50)         (10)         
      Hyperplasia                                     15 (30%)      1 (10%)     21 (42%)                  21 (42%)                  
      Necrosis                                         1 (2%)                    1 (2%)                                             
   Islets, Pancreatic                                 (50)         (10)         (50)         (10)         (50)         (10)         
      Hyperplasia                                                                1 (2%)                                             
   Parathyroid Gland                                  (47)         (10)         (45)         (10)         (47)         (10)         
      Hyperplasia                                      1 (2%)                                                                       
   Pituitary Gland                                    (50)         (10)         (49)         (10)         (50)         (10)         
      Pigmentation, Hemosiderin                                                  1 (2%)                    1 (2%)                   
      Craniopharyngeal Duct, Pars Intermedia, Cyst                                                                                  
          Multilocular                                                                                     1 (2%)                   
      Pars Distalis, Cyst                              3 (6%)                    7 (14%)                   4 (8%)       2 (20%)     
      Pars Distalis, Degeneration, Cystic              1 (2%)                                                                       
      Pars Distalis, Hyperplasia                      19 (38%)      3 (30%)     10 (20%)      5 (50%)     14 (28%)      7 (70%)     

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

                                                             Page   12                                                              
NTP Experiment-Test: 05165-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                  4,4 THIOBIS-(6-T-BUTYL-M-CRESOL)                             Date: 11/09/95  
Route: DOSED FEED                                                                                                 Time: 19:42:26  
____________________________________________________________________________________________________________________________________

         FISCHER 344 RATS MALE                      0 PPM       0 PPM        500 PPM      500 PPM      1000 PPM     1000 PPM        
                                                                 65 PATH                   65 PATH                   65 PATH        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ENDOCRINE SYSTEM - CONT                                                                                                             
      Pars Distalis, Pigmentation, Hemosiderin                      1 (10%)                                                         
      Pars Intermedia, Cyst                            1 (2%)                                              1 (2%)                   
      Pars Intermedia, Ectasia                         1 (2%)                                                                       
   Thyroid Gland                                      (50)         (10)         (50)         (10)         (50)         (10)         
      Cyst                                             1 (2%)                                                                       
      Inflammation, Chronic Active                     2 (4%)                                                                       
      C-Cell, Hyperplasia                              9 (18%)      4 (40%)     12 (24%)      2 (20%)     14 (28%)                  
      Follicle, Cyst                                                                                       1 (2%)                   
      Follicular Cell, Hyperplasia                     1 (2%)                                              1 (2%)                   
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Coagulating Gland                                                            (1)                                                 
      Inflammation, Chronic Active                                               1 (100%)                                           
   Epididymis                                         (50)         (10)         (50)         (10)         (50)         (10)         
      Granuloma Sperm                                  1 (2%)                    5 (10%)                   4 (8%)                   
      Hypospermia                                                   2 (20%)                   1 (10%)                               
   Preputial Gland                                    (50)         (10)         (49)         (10)         (49)         (10)         
      Hyperplasia                                      3 (6%)                    6 (12%)                   6 (12%)                  
      Inflammation, Chronic Active                    48 (96%)      8 (80%)     43 (88%)      9 (90%)     39 (80%)      8 (80%)     
      Metaplasia, Osseous                              1 (2%)                                                                       
      Duct, Dilatation                                                           1 (2%)                    3 (6%)                   
   Prostate                                           (49)         (10)         (50)         (10)         (50)         (10)         
      Inflammation, Chronic Active                    33 (67%)      8 (80%)     32 (64%)      7 (70%)     28 (56%)     10 (100%)    
   Seminal Vesicle                                    (49)         (10)         (50)         (10)         (50)         (10)         
      Atrophy                                                                    1 (2%)                                             
      Inflammation, Chronic Active                     1 (2%)                    1 (2%)                                             
   Testes                                             (50)         (10)         (49)         (10)         (50)         (10)         
      Granuloma Sperm                                                                         1 (10%)                               
      Inflammation, Chronic                            1 (2%)                                                                       
      Mineralization                                  35 (70%)                  37 (76%)      2 (20%)     44 (88%)      2 (20%)     
      Spermatocele                                                               1 (2%)                                             
      Arteriole, Inflammation, Chronic Active          1 (2%)                                                                       
      Interstitial Cell, Hyperplasia                  23 (46%)     10 (100%)    29 (59%)     10 (100%)    28 (56%)     10 (100%)    
      Seminiferous Tubule, Atrophy                     5 (10%)      1 (10%)      1 (2%)       1 (10%)      1 (2%)       1 (10%)     
____________________________________________________________________________________________________________________________________
                                                                                                                                    

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

                                                             Page   13                                                              
NTP Experiment-Test: 05165-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                  4,4 THIOBIS-(6-T-BUTYL-M-CRESOL)                             Date: 11/09/95  
Route: DOSED FEED                                                                                                 Time: 19:42:26  
____________________________________________________________________________________________________________________________________

         FISCHER 344 RATS MALE                      0 PPM       0 PPM        500 PPM      500 PPM      1000 PPM     1000 PPM        
                                                                 65 PATH                   65 PATH                   65 PATH        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (50)         (10)         (50)         (10)         (50)         (10)         
      Femoral, Myelofibrosis                           1 (2%)                    1 (2%)                                             
   Lymph Node                                         (24)                      (19)                      (26)                      
      Mediastinal, Edema                               1 (4%)                                                                       
      Mediastinal, Hyperplasia, Plasma Cell                                                                1 (4%)                   
   Lymph Node, Mandibular                             (48)         (10)         (50)         (10)         (50)         (10)         
      Cyst                                                                       1 (2%)                                             
      Hyperplasia, Plasma Cell                                                   1 (2%)       1 (10%)      2 (4%)                   
      Necrosis, Coagulative                                                      1 (2%)                                             
      Sinus, Ectasia                                                1 (10%)                                             1 (10%)     
   Lymph Node, Mesenteric                             (50)         (10)         (50)         (10)         (49)         (10)         
      Sinus, Ectasia                                   1 (2%)                                                                       
   Spleen                                             (50)         (10)         (50)         (10)         (49)         (10)         
      Depletion Lymphoid                               1 (2%)                                                                       
      Fibrosis                                         4 (8%)       1 (10%)      9 (18%)      1 (10%)      3 (6%)                   
      Hematopoietic Cell Proliferation                                           1 (2%)                    1 (2%)                   
      Necrosis, Coagulative                            1 (2%)                                              2 (4%)                   
      Thrombosis                                                                                           1 (2%)                   
      Red Pulp, Atrophy                                2 (4%)                    1 (2%)                                             
   Thymus                                             (48)         (10)         (46)         (10)         (46)         (10)         
      Ectopic Parathyroid Gland                        1 (2%)                    1 (2%)                                             
      Ectopic Thyroid                                  1 (2%)                    1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (47)         (10)         (47)         (10)         (46)         (10)         
      Hyperplasia, Cystic                             28 (60%)      9 (90%)     37 (79%)     10 (100%)    34 (74%)     10 (100%)    
   Skin                                               (50)         (10)         (50)         (10)         (50)         (10)         
      Acanthosis                                                                 1 (2%)                                             
      Hyperplasia, Squamous                                                      1 (2%)                                             
      Inflammation, Chronic Active                                               1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (50)         (10)         (50)         (10)         (50)         (10)         
      Cranium, Fibrous Osteodystrophy                  1 (2%)                                                                       
      Femur, Fibrous Osteodystrophy                    1 (2%)                                                                       
   Skeletal Muscle                                    (50)         (10)         (50)         (10)         (50)         (10)         
      Fibrosis                                         1 (2%)                                                                       
      Mineralization                                                                                       1 (2%)                   
      Necrosis, Coagulative                            7 (14%)      2 (20%)      7 (14%)                   5 (10%)      1 (10%)     
____________________________________________________________________________________________________________________________________
                                                                                                                                    

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

                                                             Page   14                                                              
NTP Experiment-Test: 05165-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                  4,4 THIOBIS-(6-T-BUTYL-M-CRESOL)                             Date: 11/09/95  
Route: DOSED FEED                                                                                                 Time: 19:42:26  
____________________________________________________________________________________________________________________________________

         FISCHER 344 RATS MALE                      0 PPM       0 PPM        500 PPM      500 PPM      1000 PPM     1000 PPM        
                                                                 65 PATH                   65 PATH                   65 PATH        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (50)         (10)         (50)         (10)         (50)         (10)         
      Compression                                      4 (8%)                    1 (2%)                    2 (4%)                   
      Cyst                                             1 (2%)                                                                       
      Hemorrhage, Acute                                2 (4%)                                              2 (4%)                   
      Hydrocephalus                                    4 (8%)                    1 (2%)                    2 (4%)                   
      Inflammation, Suppurative                        1 (2%)                                                                       
      Necrosis                                                                                             1 (2%)                   
   Spinal Cord                                        (2)                       (2)                       (3)          (1)          
      Hemorrhage, Acute                                1 (50%)                                             1 (33%)                  
      White Matter, Degeneration                       1 (50%)                                             2 (67%)                  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Lung                                               (49)         (10)         (50)         (10)         (50)         (10)         
      Inflammation, Chronic Active                    10 (20%)      1 (10%)      6 (12%)      1 (10%)      8 (16%)      2 (20%)     
      Leukocytosis                                                               1 (2%)                                             
      Metaplasia, Osseous                              2 (4%)                                                           1 (10%)     
      Alveolar Epithelium, Hyperplasia                 4 (8%)                    1 (2%)       1 (10%)      3 (6%)                   
      Alveolus, Infiltration Cellular, Histiocyte     10 (20%)                  10 (20%)                  13 (26%)                  
   Nose                                               (50)         (10)         (50)         (10)         (50)         (10)         
      Inflammation, Chronic Active                     3 (6%)                    3 (6%)       1 (10%)      4 (8%)       1 (10%)     
      Thrombosis                                                                 1 (2%)                                             
      Nasolacrimal Duct, Inflammation, Suppurative    15 (30%)      2 (20%)     13 (26%)                   4 (8%)       1 (10%)     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Ear                                                (1)                       (1)                       (2)                       
      Inflammation, Chronic Active                     1 (100%)                                                                     
   Eye                                                (3)                       (2)                       (5)                       
      Anterior Chamber, Hemorrhage, Acute                                                                  1 (20%)                  
      Cornea, Inflammation, Chronic Active             1 (33%)                                             1 (20%)                  
      Lens, Cataract                                   1 (33%)                   1 (50%)                   4 (80%)                  
      Retina, Atrophy                                  1 (33%)                   2 (100%)                  3 (60%)                  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (50)         (10)         (50)         (10)         (50)         (10)         
      Bacterium                                        1 (2%)                                                                       
      Cyst                                             1 (2%)       1 (10%)      2 (4%)                    1 (2%)                   
      Inflammation, Chronic Active                                                                         1 (2%)                   
      Inflammation, Suppurative                        1 (2%)                                                                       
      Necrosis, Coagulative                            2 (4%)                    2 (4%)                                             
      Nephropathy, Chronic                            47 (94%)     10 (100%)    48 (96%)     10 (100%)    47 (94%)     10 (100%)    

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

                                                             Page   15                                                              
NTP Experiment-Test: 05165-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                  4,4 THIOBIS-(6-T-BUTYL-M-CRESOL)                             Date: 11/09/95  
Route: DOSED FEED                                                                                                 Time: 19:42:26  
____________________________________________________________________________________________________________________________________

         FISCHER 344 RATS MALE                      0 PPM       0 PPM        500 PPM      500 PPM      1000 PPM     1000 PPM        
                                                                 65 PATH                   65 PATH                   65 PATH        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
URINARY SYSTEM - CONT                                                                                                               
   Urinary Bladder                                    (49)         (10)         (50)         (10)         (50)         (10)         
      Inflammation, Chronic Active                                               1 (2%)                                             
      Transitional Epithelium, Hyperplasia                                       1 (2%)                                             
                                                                                                                                    

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

                                                             Page   16                                                              
NTP Experiment-Test: 05165-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                  4,4 THIOBIS-(6-T-BUTYL-M-CRESOL)                             Date: 11/09/95  
Route: DOSED FEED                                                                                                 Time: 19:42:26  
____________________________________________________________________________________________________________________________________

         FISCHER 344 RATS MALE                     2500 PPM     2500 PPM                                                            
                                                                 65 PATH                                                            
____________________________________________________________________________________________________________________________________

DISPOSITION SUMMARY                                                                                                                 

  Animals Initially In Study                          50           10                                                               

  Scheduled Sacrifice                                              10                                                               
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                23                                                                            
    Natural Death                                      9                                                                            
  Survivors                                                                                                                         
    Terminal Sacrifice                                18                                                                            

  Animals Examined Microscopically                    49           10                                                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Intestine Large, Colon                             (48)         (10)                                                             
      Inflammation, Chronic Active                     1 (2%)                                                                       
   Intestine Large, Rectum                            (48)         (10)                                                             
      Parasite Metazoan                                1 (2%)       1 (10%)                                                         
   Intestine Large, Cecum                             (49)         (10)                                                             
      Inflammation, Chronic Active                     1 (2%)                                                                       
   Liver                                              (49)         (10)                                                             
      Basophilic Focus                                22 (45%)     10 (100%)                                                        
      Clear Cell Focus                                 1 (2%)                                                                       
      Eosinophilic Focus                               1 (2%)                                                                       
      Fatty Change                                    15 (31%)                                                                      
      Hepatodiaphragmatic Nodule                       4 (8%)                                                                       
      Inflammation, Chronic                            3 (6%)                                                                       
      Mixed Cell Focus                                15 (31%)      5 (50%)                                                         
      Necrosis, Coagulative                            2 (4%)                                                                       
      Thrombosis                                       1 (2%)                                                                       
      Bile Duct, Hyperplasia                          46 (94%)      9 (90%)                                                         
      Hepatocyte, Degeneration, Cystic                11 (22%)                                                                      
      Hepatocyte, Vacuolization Cytoplasmic           18 (37%)     10 (100%)                                                        
      Periportal, Kupffer Cell, Hypertrophy           31 (63%)     10 (100%)                                                        
   Mesentery                                          (9)                                                                           
      Hemorrhage, Acute                                1 (11%)                                                                      
      Inflammation, Chronic Active                     1 (11%)                                                                      
      Inflammation, Necrotizing                        4 (44%)                                                                      
      Mineralization                                   1 (11%)                                                                      
   Pancreas                                           (49)         (10)                                                             
      Acinus, Atrophy                                 30 (61%)      3 (30%)                                                         
   Stomach, Forestomach                               (49)         (10)                                                             
      Acanthosis                                       1 (2%)                                                                       
   Stomach, Glandular                                 (49)         (10)                                                             
      Mineralization                                   1 (2%)                                                                       
____________________________________________________________________________________________________________________________________

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

                                                             Page   17                                                              
NTP Experiment-Test: 05165-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                  4,4 THIOBIS-(6-T-BUTYL-M-CRESOL)                             Date: 11/09/95  
Route: DOSED FEED                                                                                                 Time: 19:42:26  
____________________________________________________________________________________________________________________________________

         FISCHER 344 RATS MALE                     2500 PPM     2500 PPM                                                            
                                                                 65 PATH                                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Heart                                              (49)         (10)                                                             
      Cardiomyopathy, Chronic                         39 (80%)     10 (100%)                                                        
      Metaplasia, Cartilagenous                        1 (2%)                                                                       
      Mineralization                                   1 (2%)                                                                       
      Thrombosis                                       3 (6%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (49)         (10)                                                             
      Accessory Adrenal Cortical Nodule                3 (6%)                                                                       
      Degeneration, Fatty                             16 (33%)                                                                      
      Hyperplasia                                     13 (27%)                                                                      
      Necrosis, Coagulative                            4 (8%)                                                                       
   Adrenal Medulla                                    (49)         (10)                                                             
      Hyperplasia                                     18 (37%)                                                                      
   Islets, Pancreatic                                 (49)         (10)                                                             
      Hyperplasia                                      1 (2%)                                                                       
   Parathyroid Gland                                  (46)         (10)                                                             
      Hyperplasia                                      2 (4%)                                                                       
   Pituitary Gland                                    (49)         (10)                                                             
      Pars Distalis, Cyst                              3 (6%)                                                                       
      Pars Distalis, Hyperplasia                      20 (41%)      2 (20%)                                                         
      Pars Intermedia, Cyst                            1 (2%)                                                                       
   Thyroid Gland                                      (49)         (10)                                                             
      Cyst                                                          1 (10%)                                                         
      Inflammation, Chronic Active                     1 (2%)                                                                       
      C-Cell, Hyperplasia                              8 (16%)                                                                      
      Follicle, Cyst                                   1 (2%)                                                                       
      Follicular Cell, Hyperplasia                     1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Epididymis                                         (49)         (10)                                                             
      Granuloma Sperm                                  9 (18%)                                                                      
   Preputial Gland                                    (49)         (10)                                                             
      Hyperplasia                                      5 (10%)                                                                      
      Inflammation, Chronic Active                    44 (90%)      6 (60%)                                                         
      Duct, Dilatation                                 1 (2%)                                                                       

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

                                                             Page   18                                                              
NTP Experiment-Test: 05165-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                  4,4 THIOBIS-(6-T-BUTYL-M-CRESOL)                             Date: 11/09/95  
Route: DOSED FEED                                                                                                 Time: 19:42:26  
____________________________________________________________________________________________________________________________________

         FISCHER 344 RATS MALE                     2500 PPM     2500 PPM                                                            
                                                                 65 PATH                                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
GENITAL SYSTEM - CONT                                                                                                               
   Prostate                                           (48)         (10)                                                             
      Inflammation, Chronic Active                    40 (83%)     10 (100%)                                                        
   Testes                                             (49)         (10)                                                             
      Cyst                                             1 (2%)                                                                       
      Mineralization                                  29 (59%)      1 (10%)                                                         
      Interstitial Cell, Hyperplasia                  34 (69%)     10 (100%)                                                        
      Seminiferous Tubule, Atrophy                     5 (10%)                                                                      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Lymph Node, Mandibular                             (49)         (10)                                                             
      Cyst                                             2 (4%)                                                                       
   Spleen                                             (49)         (10)                                                             
      Ectopic Tissue                                   2 (4%)                                                                       
      Fibrosis                                         4 (8%)                                                                       
      Hematopoietic Cell Proliferation                 1 (2%)                                                                       
      Necrosis, Coagulative                            2 (4%)                                                                       
      Red Pulp, Atrophy                                2 (4%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (49)         (10)                                                             
      Hyperplasia, Cystic                             33 (67%)     10 (100%)                                                        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (49)         (10)                                                             
      Cranium, Fibrous Osteodystrophy                  1 (2%)                                                                       
      Femur, Fibrous Osteodystrophy                    1 (2%)                                                                       
   Skeletal Muscle                                    (49)         (10)                                                             
      Necrosis, Coagulative                            7 (14%)      1 (10%)                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (49)         (10)                                                             
      Hemorrhage, Acute                                2 (4%)                                                                       
      Inflammation, Suppurative                        1 (2%)                                                                       
      Necrosis                                         1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    

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

                                                             Page   19                                                              
NTP Experiment-Test: 05165-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                  4,4 THIOBIS-(6-T-BUTYL-M-CRESOL)                             Date: 11/09/95  
Route: DOSED FEED                                                                                                 Time: 19:42:26  
____________________________________________________________________________________________________________________________________

         FISCHER 344 RATS MALE                     2500 PPM     2500 PPM                                                            
                                                                 65 PATH                                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Lung                                               (49)         (10)                                                             
      Hemorrhage, Acute                                3 (6%)                                                                       
      Inflammation, Chronic Active                     7 (14%)      2 (20%)                                                         
      Metaplasia, Osseous                              1 (2%)                                                                       
      Alveolar Epithelium, Hyperplasia                 4 (8%)                                                                       
      Alveolus, Infiltration Cellular, Histiocyte      9 (18%)                                                                      
   Nose                                               (49)         (10)                                                             
      Fungus                                           1 (2%)       1 (10%)                                                         
      Inflammation, Chronic Active                     7 (14%)      1 (10%)                                                         
      Nasolacrimal Duct, Inflammation, Suppurative    10 (20%)                                                                      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (49)         (10)                                                             
      Cyst                                             1 (2%)                                                                       
      Necrosis, Coagulative                            2 (4%)                                                                       
      Nephropathy, Chronic                            47 (96%)     10 (100%)                                                        
                                                                                                                                    

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

                                                             Page   20                                                              
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                             ----------              END OF REPORT             ----------                                           
                             ------------------------------------------------------------                                           
NTP Experiment-Test: 05165-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                  4,4 THIOBIS-(6-T-BUTYL-M-CRESOL)                             Date: 11/09/95
Route: DOSED FEED                                                                                                 Time: 21:02:21




       Facility:  Battelle Columbus Laboratory

       Chemical CAS #:  96-69-5

       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: 05165-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                  4,4 THIOBIS-(6-T-BUTYL-M-CRESOL)                             Date: 11/09/95  
Route: DOSED FEED                                                                                                 Time: 21:02:21  
____________________________________________________________________________________________________________________________________

         FISCHER 344 RATS MALE                     0 PPM        0 PPM        500 PPM      500 PPM      1000 PPM     1000 PPM        
                                                    NEURO        HCU          NEURO        HCU          NEURO        HCU            
____________________________________________________________________________________________________________________________________

DISPOSITION SUMMARY                                                                                                                 

  Animals Initially In Study                          40           15           40           15           40           15           

  Scheduled Sacrifice                                 40           15           40           15           40           12           
  Early Deaths                                                                                                                      
    Natural Death                                                                                                       2           
    Moribund Sacrifice                                                                                                  1           
  Survivors                                                                                                                         

  Animals Examined Microscopically                    20                        20                        20                        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    

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

                                                             Page    2                                                              
NTP Experiment-Test: 05165-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                  4,4 THIOBIS-(6-T-BUTYL-M-CRESOL)                             Date: 11/09/95  
Route: DOSED FEED                                                                                                 Time: 21:02:21  
____________________________________________________________________________________________________________________________________

         FISCHER 344 RATS MALE                     0 PPM        0 PPM        500 PPM      500 PPM      1000 PPM     1000 PPM        
                                                    NEURO        HCU          NEURO        HCU          NEURO        HCU            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Skeletal Muscle                                    (20)                      (20)                      (20)                      
      Necrosis, Coagulative                            9 (45%)                  14 (70%)                  17 (85%)                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   None                                                                                                                             

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

                                                             Page    3                                                              
NTP Experiment-Test: 05165-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                  4,4 THIOBIS-(6-T-BUTYL-M-CRESOL)                             Date: 11/09/95  
Route: DOSED FEED                                                                                                 Time: 21:02:21  
____________________________________________________________________________________________________________________________________

         FISCHER 344 RATS MALE                     2500 PPM     2500 PPM                                                            
                                                    NEURO        HCU                                                                
____________________________________________________________________________________________________________________________________

DISPOSITION SUMMARY                                                                                                                 

  Animals Initially In Study                          40           15                                                               

  Scheduled Sacrifice                                 40           14                                                               
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                              1                                                               
  Survivors                                                                                                                         

  Animals Examined Microscopically                    20                                                                            
   Skeletal Muscle                                    (20)                                                                          
      Necrosis, Coagulative                            9 (45%)                                                                      
                                                                                                                                    

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

                                                             Page    4                                                              
                             ------------------------------------------------------------                                           
                             ----------              END OF REPORT             ----------                                           
                             ------------------------------------------------------------