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TDMS Study 05181-03 Pathology Tables

NTP Experiment-Test: 05181-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/20/96
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 15:30:26

                                                           CORE STUDY




       Facility:  Battelle Northwest

       Chemical CAS #:  0109-99-9

       Lock Date:  03/24/93

       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: 05181-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/20/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 15:30:26  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS FEMALE                   CONTROL      200 PPM      600 PPM      1800 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially In Study                          50           50           50           50                                     
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                18           22           19           19                                     
    Natural Death                                      7            3            5            5                                     
  Survivors                                                                                                                         
    Terminal Sacrifice                                25           25           26           26                                     
  Animals Examined Microscopically                    50           50           50           50                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Intestine Large, Colon                             (47)         (49)         (49)         (46)                                   
      Parasite Metazoan                                1 (2%)       1 (2%)       5 (10%)      7 (15%)                               
   Intestine Large, Rectum                            (48)         (50)         (50)         (47)                                   
      Parasite Metazoan                                6 (13%)      2 (4%)       6 (12%)      5 (11%)                               
   Intestine Large, Cecum                             (47)         (49)         (46)         (45)                                   
      Parasite Metazoan                                2 (4%)       3 (6%)       4 (9%)       7 (16%)                               
      Ulcer                                                         1 (2%)                                                          
   Intestine Small, Ileum                             (45)         (49)         (46)         (45)                                   
      Parasite Metazoan                                                                       1 (2%)                                
   Liver                                              (50)         (49)         (50)         (50)                                   
      Angiectasis                                      3 (6%)       4 (8%)       1 (2%)                                             
      Basophilic Focus                                 6 (12%)      2 (4%)                    6 (12%)                               
      Clear Cell Focus                                 6 (12%)      7 (14%)                   6 (12%)                               
      Degeneration, Cystic                             2 (4%)                                 2 (4%)                                
      Hemorrhage                                                    1 (2%)                                                          
      Hepatodiaphragmatic Nodule                       6 (12%)      5 (10%)      3 (6%)      10 (20%)                               
      Hyperplasia, Reticulum Cell                      2 (4%)                                                                       
      Inflammation, Granulomatous                                   2 (4%)                                                          
      Vacuolization Cytoplasmic                        7 (14%)     16 (33%)     12 (24%)      3 (6%)                                
      Bile Duct, Hyperplasia                                                                  1 (2%)                                
      Hepatocyte, Necrosis                             2 (4%)       1 (2%)       1 (2%)       3 (6%)                                
      Hepatocyte, Regeneration                                      1 (2%)                                                          
      Serosa, Fibrosis                                 1 (2%)                                                                       
   Mesentery                                          (6)          (9)          (9)          (3)                                    
      Fat, Inflammation, Granulomatous                 2 (33%)                                1 (33%)                               
      Fat, Mineralization                                           1 (11%)                                                         
      Fat, Necrosis                                    4 (67%)      8 (89%)      7 (78%)      2 (67%)                               
   Oral Mucosa                                                                  (1)                                                 
      Hyperplasia                                                                1 (100%)                                           
   Pancreas                                           (48)         (50)         (50)         (49)                                   
      Atrophy                                          3 (6%)       6 (12%)      4 (8%)       7 (14%)                               
   Stomach, Forestomach                               (49)         (49)         (50)         (49)                                   
      Hyperkeratosis                                   1 (2%)       1 (2%)       1 (2%)       1 (2%)                                
      Hyperplasia                                      6 (12%)      7 (14%)      3 (6%)       3 (6%)                                
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    2                                                              
NTP Experiment-Test: 05181-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/20/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 15:30:26  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS FEMALE                   CONTROL      200 PPM      600 PPM      1800 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Inflammation, Suppurative                        1 (2%)       3 (6%)                    2 (4%)                                
      Necrosis                                                      1 (2%)                                                          
      Ulcer                                            2 (4%)       5 (10%)      1 (2%)       2 (4%)                                
   Stomach, Glandular                                 (49)         (49)         (50)         (49)                                   
      Mineralization                                   1 (2%)                                 1 (2%)                                
      Necrosis                                         1 (2%)                                                                       
      Ulcer                                            2 (4%)                    2 (4%)                                             
   Tooth                                                           (1)                                                              
      Developmental Malformation                                    1 (100%)                                                        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Blood Vessel                                       (50)         (50)         (50)         (50)                                   
      Aorta, Thrombosis                                1 (2%)                                                                       
   Heart                                              (50)         (50)         (50)         (50)                                   
      Cardiomyopathy                                                             1 (2%)       1 (2%)                                
      Atrium, Thrombosis                               2 (4%)       1 (2%)       1 (2%)                                             
      Endocardium, Hemorrhage                                                    1 (2%)                                             
      Endocardium, Atrium, Fibrosis                                                           1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (50)         (50)         (50)         (50)                                   
      Hemorrhage                                       1 (2%)       1 (2%)                                                          
      Necrosis                                                      1 (2%)                                                          
      Vacuolization Cytoplasmic                        6 (12%)     10 (20%)      7 (14%)     11 (22%)                               
      Zona Reticularis, Pigmentation                   1 (2%)                                                                       
   Adrenal Medulla                                    (50)         (50)         (49)         (50)                                   
      Hemorrhage                                                    1 (2%)                                                          
      Hyperplasia                                      4 (8%)       2 (4%)       9 (18%)      6 (12%)                               
      Necrosis                                                                   1 (2%)                                             
   Islets, Pancreatic                                 (48)         (50)         (50)         (49)                                   
      Hyperplasia                                      1 (2%)                                                                       
   Parathyroid Gland                                  (43)         (43)         (46)         (42)                                   
      Hyperplasia                                                   1 (2%)                    2 (5%)                                
   Pituitary Gland                                    (49)         (49)         (50)         (50)                                   
      Cyst                                             9 (18%)      6 (12%)      4 (8%)       6 (12%)                               
      Hemorrhage                                       2 (4%)       1 (2%)       1 (2%)                                             
      Pars Distalis, Hyperplasia                       5 (10%)      3 (6%)       6 (12%)      2 (4%)                                
      Pars Intermedia, Hyperplasia                                                            1 (2%)                                
      Pars Nervosa, Cyst                               1 (2%)                                                                       
   Thyroid Gland                                      (48)         (50)         (50)         (49)                                   
      Ultimobranchial Cyst                                          1 (2%)                    1 (2%)                                
      C-Cell, Hyperplasia                              5 (10%)      6 (12%)      7 (14%)     10 (20%)                               
____________________________________________________________________________________________________________________________________
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    3                                                              
NTP Experiment-Test: 05181-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/20/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 15:30:26  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS FEMALE                   CONTROL      200 PPM      600 PPM      1800 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Clitoral Gland                                     (48)         (48)         (46)         (49)                                   
      Cyst                                                                       1 (2%)       1 (2%)                                
      Hyperplasia                                      1 (2%)       4 (8%)       3 (7%)       1 (2%)                                
      Inflammation, Chronic                            2 (4%)                                 3 (6%)                                
      Inflammation, Granulomatous                      1 (2%)                                                                       
      Inflammation, Suppurative                        2 (4%)       3 (6%)       3 (7%)       2 (4%)                                
   Ovary                                              (50)         (50)         (50)         (50)                                   
      Cyst                                             9 (18%)      3 (6%)       5 (10%)      4 (8%)                                
      Bilateral, Cyst                                               1 (2%)                                                          
   Uterus                                             (50)         (50)         (50)         (50)                                   
      Atrophy                                                       2 (4%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (49)         (50)         (50)         (50)                                   
      Hyperplasia, Reticulum Cell                      3 (6%)       1 (2%)                    1 (2%)                                
      Myelofibrosis                                    1 (2%)                                 2 (4%)                                
   Lymph Node                                         (7)          (7)          (6)          (5)                                    
      Iliac, Hyperplasia, Histiocytic                  1 (14%)                                                                      
      Iliac, Hyperplasia, Lymphoid                     2 (29%)                                                                      
      Iliac, Pigmentation                              1 (14%)                                                                      
      Lumbar, Pigmentation                             1 (14%)                                                                      
      Pancreatic, Pigmentation                                      1 (14%)                                                         
      Renal, Hyperplasia, Lymphoid                     2 (29%)                                                                      
   Lymph Node, Bronchial                              (46)         (45)         (41)         (45)                                   
      Hemorrhage                                                    1 (2%)                    1 (2%)                                
   Lymph Node, Mandibular                             (45)         (47)         (48)         (44)                                   
      Hyperplasia, Lymphoid                                                      1 (2%)                                             
      Infiltration Cellular, Histiocyte                1 (2%)                                                                       
   Lymph Node, Mesenteric                             (48)         (50)         (50)         (50)                                   
      Hemorrhage                                       1 (2%)                                                                       
      Inflammation, Suppurative                                     1 (2%)                                                          
      Necrosis                                         1 (2%)                                                                       
   Lymph Node, Mediastinal                            (48)         (48)         (48)         (46)                                   
      Hemorrhage                                       1 (2%)       1 (2%)       1 (2%)                                             
      Hyperplasia, Lymphoid                            1 (2%)                                                                       
      Inflammation, Suppurative                        1 (2%)                                                                       
      Pigmentation                                     1 (2%)                                                                       
   Spleen                                             (50)         (50)         (50)         (50)                                   
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    4                                                              
NTP Experiment-Test: 05181-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/20/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 15:30:26  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS FEMALE                   CONTROL      200 PPM      600 PPM      1800 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
HEMATOPOIETIC SYSTEM - CONT                                                                                                         
      Accessory Spleen                                                                        1 (2%)                                
      Angiectasis                                                   1 (2%)                                                          
      Fibrosis                                                      1 (2%)       1 (2%)       3 (6%)                                
      Hematopoietic Cell Proliferation                 3 (6%)       1 (2%)                    1 (2%)                                
      Hemorrhage                                       2 (4%)       3 (6%)                    1 (2%)                                
      Necrosis                                                      2 (4%)       1 (2%)       2 (4%)                                
      Pigmentation                                                  1 (2%)                                                          
   Thymus                                             (50)         (50)         (49)         (48)                                   
      Cyst                                                          1 (2%)       1 (2%)       1 (2%)                                
      Hyperplasia, Lymphoid                                                      1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (50)         (50)         (50)         (50)                                   
      Galactocele                                      3 (6%)       1 (2%)                                                          
      Hyperplasia                                                                             1 (2%)                                
      Inflammation, Suppurative                                                               1 (2%)                                
      Duct, Dilatation                                                           1 (2%)                                             
      Duct, Metaplasia, Squamous                       1 (2%)                                                                       
      Epithelium, Hyperplasia                                       1 (2%)                                                          
   Skin                                               (50)         (50)         (50)         (50)                                   
      Hyperkeratosis                                   3 (6%)                                                                       
      Hyperplasia                                      1 (2%)                                                                       
      Inflammation, Suppurative                        1 (2%)                                                                       
      Ulcer                                                         2 (4%)       3 (6%)       1 (2%)                                
      Epidermis, Cyst                                  2 (4%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (50)         (50)         (50)         (50)                                   
      Fibrosis                                                                   1 (2%)                                             
      Cartilage, Sternum, Degeneration, Mucoid         1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (50)         (50)         (50)         (50)                                   
      Gliosis                                          1 (2%)                                                                       
      Hemorrhage                                       6 (12%)      3 (6%)       5 (10%)      5 (10%)                               
      Necrosis                                                                   1 (2%)                                             
      Meninges, Hyperplasia                                                                   1 (2%)                                
      Ventricle, Hydrocephalus                         5 (10%)      8 (16%)      8 (16%)      1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    5                                                              
NTP Experiment-Test: 05181-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/20/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 15:30:26  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS FEMALE                   CONTROL      200 PPM      600 PPM      1800 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Larynx                                             (50)         (50)         (48)         (48)                                   
      Foreign Body                                     6 (12%)      2 (4%)       6 (13%)      7 (15%)                               
      Inflammation, Suppurative                        3 (6%)       1 (2%)                    1 (2%)                                
      Epiglottis, Metaplasia, Squamous                 1 (2%)       1 (2%)                                                          
      Epithelium, Hyperplasia                          3 (6%)       3 (6%)       3 (6%)       8 (17%)                               
      Epithelium, Metaplasia, Squamous                 2 (4%)       1 (2%)       2 (4%)       5 (10%)                               
      Glands, Inflammation, Suppurative                3 (6%)                    1 (2%)       1 (2%)                                
   Lung                                               (50)         (50)         (49)         (50)                                   
      Hemorrhage                                       8 (16%)     15 (30%)     11 (22%)     10 (20%)                               
      Inflammation, Granulomatous                                                1 (2%)                                             
      Alveolar Epithelium, Fibrosis                    1 (2%)                                                                       
      Alveolar Epithelium, Hyperplasia                              2 (4%)       3 (6%)       1 (2%)                                
      Alveolar Epithelium, Infiltration Cellular,                                                                                   
           Histiocyte                                  5 (10%)      3 (6%)       4 (8%)       2 (4%)                                
      Alveolar Epithelium, Pigmentation                1 (2%)                                                                       
   Nose                                               (49)         (49)         (50)         (49)                                   
      Foreign Body                                     1 (2%)       3 (6%)       3 (6%)       2 (4%)                                
      Inflammation, Suppurative                        2 (4%)       4 (8%)       4 (8%)       3 (6%)                                
      Goblet Cell, Respiratory Epithelium,                                                                                          
          Hypertrophy                                  1 (2%)                                 1 (2%)                                
      Nasolacrimal Duct, Inflammation, Suppurative                  4 (8%)       2 (4%)       1 (2%)                                
      Nasopharyngeal Duct, Hyperplasia                              1 (2%)                                                          
      Olfactory Epithelium, Metaplasia                              1 (2%)                                                          
      Olfactory Epithelium, Metaplasia, Squamous                                              1 (2%)                                
      Respiratory Epithelium, Hyperplasia                                        1 (2%)       1 (2%)                                
      Respiratory Epithelium, Metaplasia, Squamous                               1 (2%)       1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                (3)          (3)          (1)          (3)                                    
      Atrophy                                          1 (33%)                                                                      
      Cataract                                         1 (33%)      2 (67%)      1 (100%)     2 (67%)                               
      Bilateral, Cataract                                                                     1 (33%)                               
      Cornea, Hyperplasia                              1 (33%)                                                                      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (50)         (50)         (50)         (50)                                   
      Cyst                                                          2 (4%)                    1 (2%)                                
      Nephropathy, Chronic                            48 (96%)     44 (88%)     43 (86%)     42 (84%)                               
      Cortex, Necrosis                                              1 (2%)                                                          
      Papilla, Necrosis                                1 (2%)                                                                       
      Pelvis, Dilatation                               1 (2%)                                                                       
      Renal Tubule, Degeneration                                                 1 (2%)                                             
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    6                                                              
NTP Experiment-Test: 05181-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/20/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 15:30:26  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS FEMALE                   CONTROL      200 PPM      600 PPM      1800 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
URINARY SYSTEM - CONT                                                                                                               
      Renal Tubule, Mineralization                    47 (94%)     46 (92%)     50 (100%)    46 (92%)                               
      Renal Tubule, Pigmentation                                                 1 (2%)                                             
   Urinary Bladder                                    (49)         (50)         (50)         (49)                                   
      Hemorrhage                                       1 (2%)                                 1 (2%)                                
      Inflammation, Suppurative                        1 (2%)                                                                       
      Ulcer                                            1 (2%)                                                                       
      Transitional Epithelium, Hyperplasia                          2 (4%)                    1 (2%)                                
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    7                                                              
NTP Experiment-Test: 05181-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/20/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 15:30:26  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     CONTROL      200 PPM      600 PPM      1800 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially In Study                          50           50           50           50                                     
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                31           39           40           34                                     
    Natural Death                                      6            4            5           10                                     
    Accidently Killed                                  1            1                                                               
  Survivors                                                                                                                         
    Terminal Sacrifice                                12            6            5            6                                     
  Animals Examined Microscopically                    50           50           50           50                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Intestine Large, Colon                             (49)         (48)         (48)         (45)                                   
      Parasite Metazoan                                3 (6%)       6 (13%)      4 (8%)       5 (11%)                               
      Muscularis, Mineralization                                                 1 (2%)                                             
   Intestine Large, Rectum                            (49)         (49)         (48)         (48)                                   
      Parasite Metazoan                                1 (2%)       3 (6%)       2 (4%)       4 (8%)                                
   Intestine Large, Cecum                             (49)         (48)         (48)         (46)                                   
      Necrosis                                                                   1 (2%)                                             
      Parasite Metazoan                                4 (8%)       3 (6%)       4 (8%)       6 (13%)                               
      Ulcer                                            1 (2%)                                                                       
      Artery, Inflammation, Granulomatous                                        1 (2%)                                             
   Intestine Small, Ileum                             (47)         (47)         (47)         (44)                                   
      Peyer's Patch, Hyperplasia                                                 1 (2%)                                             
   Liver                                              (50)         (50)         (50)         (50)                                   
      Angiectasis                                      1 (2%)       6 (12%)      3 (6%)       4 (8%)                                
      Basophilic Focus                                              1 (2%)       1 (2%)       2 (4%)                                
      Clear Cell Focus                                              2 (4%)       2 (4%)       1 (2%)                                
      Degeneration, Cystic                             9 (18%)      6 (12%)      9 (18%)     13 (26%)                               
      Eosinophilic Focus                                                         1 (2%)                                             
      Hepatodiaphragmatic Nodule                       3 (6%)       2 (4%)                    5 (10%)                               
      Hyperplasia, Reticulum Cell                                                             1 (2%)                                
      Inflammation, Granulomatous                      1 (2%)                                                                       
      Vacuolization Cytoplasmic                        4 (8%)       3 (6%)       7 (14%)      3 (6%)                                
      Bile Duct, Hyperplasia                           7 (14%)      7 (14%)      6 (12%)      6 (12%)                               
      Hepatocyte, Necrosis                             3 (6%)       2 (4%)       2 (4%)       5 (10%)                               
      Hepatocyte, Regeneration                                                   1 (2%)                                             
      Periportal, Fibrosis                                                       1 (2%)       1 (2%)                                
      Serosa, Fibrosis                                              1 (2%)                                                          
      Serosa, Inflammation, Chronic                                 1 (2%)                                                          
   Mesentery                                          (15)         (17)         (18)         (10)                                   
      Artery, Inflammation, Chronic                    1 (7%)                                                                       
      Fat, Hemorrhage                                  3 (20%)                                1 (10%)                               
      Fat, Inflammation, Granulomatous                 5 (33%)      1 (6%)       2 (11%)                                            
      Fat, Mineralization                                           1 (6%)       2 (11%)                                            
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    8                                                              
NTP Experiment-Test: 05181-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/20/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 15:30:26  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     CONTROL      200 PPM      600 PPM      1800 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Fat, Necrosis                                    8 (53%)     15 (88%)     12 (67%)      9 (90%)                               
   Oral Mucosa                                        (3)                                    (1)                                    
      Hyperplasia                                      1 (33%)                                                                      
      Inflammation, Suppurative                        1 (33%)                                                                      
      Ulcer                                            1 (33%)                                                                      
      Gingival, Cyst                                   1 (33%)                                                                      
      Gingival, Foreign Body                           1 (33%)                                                                      
   Pancreas                                           (50)         (50)         (50)         (50)                                   
      Atrophy                                         18 (36%)     11 (22%)      7 (14%)     17 (34%)                               
      Artery, Inflammation, Chronic                                              1 (2%)       1 (2%)                                
      Artery, Inflammation, Granulomatous                           1 (2%)                                                          
   Stomach, Forestomach                               (50)         (49)         (49)         (50)                                   
      Diverticulum                                     1 (2%)                                 1 (2%)                                
      Hyperkeratosis                                   5 (10%)      2 (4%)       3 (6%)       5 (10%)                               
      Hyperplasia                                     10 (20%)     14 (29%)      8 (16%)     11 (22%)                               
      Inflammation, Suppurative                        3 (6%)       1 (2%)       3 (6%)       1 (2%)                                
      Mineralization                                   2 (4%)                    2 (4%)       2 (4%)                                
      Necrosis                                                                   1 (2%)       1 (2%)                                
      Ulcer                                            6 (12%)     10 (20%)      3 (6%)       6 (12%)                               
   Stomach, Glandular                                 (50)         (50)         (50)         (50)                                   
      Edema                                                                      1 (2%)                                             
      Inflammation, Suppurative                        2 (4%)                                                                       
      Metaplasia, Squamous                                                       1 (2%)                                             
      Mineralization                                   7 (14%)      1 (2%)       7 (14%)      5 (10%)                               
      Ulcer                                            1 (2%)       2 (4%)                    1 (2%)                                
   Tooth                                                           (2)          (1)          (2)                                    
      Developmental Malformation                                    1 (50%)      1 (100%)                                           
      Inflammation, Suppurative                                     1 (50%)                   2 (100%)                              
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Blood Vessel                                       (43)         (50)         (49)         (44)                                   
      Mineralization                                   3 (7%)                    4 (8%)       2 (5%)                                
      Thrombosis                                                    1 (2%)                                                          
      Aorta, Mineralization                            1 (2%)                                 2 (5%)                                
   Heart                                              (50)         (50)         (50)         (50)                                   
      Cardiomyopathy                                   8 (16%)      6 (12%)      6 (12%)      6 (12%)                               
      Mineralization                                   3 (6%)                    3 (6%)       3 (6%)                                
      Atrium, Thrombosis                               1 (2%)       4 (8%)       3 (6%)       5 (10%)                               
      Endocardium, Hyperplasia                                                   1 (2%)                                             
      Myocardium, Inflammation, Suppurative                                                   1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    9                                                              
NTP Experiment-Test: 05181-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/20/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 15:30:26  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     CONTROL      200 PPM      600 PPM      1800 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (50)         (50)         (50)         (50)                                   
      Hemorrhage                                       1 (2%)                                                                       
      Vacuolization Cytoplasmic                       14 (28%)      8 (16%)      6 (12%)      3 (6%)                                
   Adrenal Medulla                                    (48)         (50)         (50)         (49)                                   
      Hyperplasia                                     21 (44%)     19 (38%)     24 (48%)     27 (55%)                               
   Islets, Pancreatic                                 (50)         (50)         (50)         (49)                                   
      Hyperplasia                                                                1 (2%)       2 (4%)                                
   Parathyroid Gland                                  (46)         (48)         (49)         (46)                                   
      Hyperplasia                                      7 (15%)      5 (10%)     10 (20%)     11 (24%)                               
   Pituitary Gland                                    (49)         (49)         (48)         (50)                                   
      Cyst                                             5 (10%)      6 (12%)      4 (8%)       8 (16%)                               
      Hemorrhage                                       2 (4%)       3 (6%)       1 (2%)       1 (2%)                                
      Craniopharyngeal Duct, Cyst                                   1 (2%)                                                          
      Pars Distalis, Angiectasis                                    1 (2%)                                                          
      Pars Distalis, Hyperplasia                       1 (2%)       3 (6%)       3 (6%)       5 (10%)                               
      Pars Intermedia, Hyperplasia                     1 (2%)                                 1 (2%)                                
   Thyroid Gland                                      (50)         (50)         (50)         (50)                                   
      Inflammation, Suppurative                                                               1 (2%)                                
      Ultimobranchial Cyst                                          1 (2%)                                                          
      C-Cell, Hyperplasia                              5 (10%)      3 (6%)       3 (6%)       6 (12%)                               
      Follicular Cell, Hyperplasia                                               1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Epididymis                                         (50)         (50)         (50)         (50)                                   
      Hyperplasia, Tubular                                          1 (2%)                                                          
      Inflammation, Granulomatous                                   1 (2%)                                                          
      Spermatocele                                                  1 (2%)                                                          
      Artery, Inflammation, Suppurative                             1 (2%)                                                          
   Penis                                              (1)                                    (1)                                    
      Inflammation, Suppurative                        1 (100%)                                                                     
   Preputial Gland                                    (49)         (50)         (50)         (50)                                   
      Cyst                                                          2 (4%)       1 (2%)       1 (2%)                                
      Hyperplasia                                      2 (4%)       1 (2%)       3 (6%)       3 (6%)                                
      Inflammation, Chronic                            1 (2%)                                 1 (2%)                                
      Inflammation, Suppurative                        3 (6%)       1 (2%)       9 (18%)      6 (12%)                               
   Prostate                                           (50)         (50)         (50)         (50)                                   
      Inflammation, Suppurative                        6 (12%)      5 (10%)      5 (10%)      3 (6%)                                
      Epithelium, Hyperplasia                          2 (4%)       1 (2%)                    5 (10%)                               
   Seminal Vesicle                                    (50)         (50)         (50)         (50)                                   
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   10                                                              
NTP Experiment-Test: 05181-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/20/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 15:30:26  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     CONTROL      200 PPM      600 PPM      1800 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
GENITAL SYSTEM - CONT                                                                                                               
      Congestion                                       1 (2%)                                                                       
      Cyst                                                                                    1 (2%)                                
      Inflammation, Suppurative                                                  2 (4%)                                             
   Testes                                             (50)         (50)         (50)         (50)                                   
      Hemorrhage                                       1 (2%)                    1 (2%)                                             
      Inflammation, Granulomatous                                                1 (2%)       1 (2%)                                
      Artery, Inflammation                             2 (4%)       2 (4%)       2 (4%)       1 (2%)                                
      Germinal Epithelium, Atrophy                    11 (22%)      7 (14%)      5 (10%)      7 (14%)                               
      Interstitial Cell, Hyperplasia                   3 (6%)       2 (4%)       3 (6%)       3 (6%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (50)         (50)         (50)         (50)                                   
      Hyperplasia, Reticulum Cell                      1 (2%)       1 (2%)                    1 (2%)                                
      Myelofibrosis                                                              1 (2%)                                             
   Lymph Node                                         (16)         (19)         (18)         (16)                                   
      Iliac, Inflammation, Suppurative                                           1 (6%)                                             
      Iliac, Pigmentation                              1 (6%)                                                                       
      Lumbar, Pigmentation                             1 (6%)                                                                       
      Pancreatic, Hyperplasia, Histiocytic                          1 (5%)                                                          
      Renal, Ectasia                                   1 (6%)       3 (16%)                   3 (19%)                               
      Renal, Fibrosis                                               1 (5%)                                                          
      Renal, Hemorrhage                                1 (6%)       2 (11%)                                                         
      Renal, Hyperplasia, Histiocytic                               1 (5%)       1 (6%)                                             
      Renal, Pigmentation                              1 (6%)                                                                       
      Renal, Deep Cervical, Angiectasis                                          1 (6%)                                             
   Lymph Node, Bronchial                              (45)         (45)         (44)         (43)                                   
      Fibrosis                                                      3 (7%)                                                          
      Hemorrhage                                                                 1 (2%)       1 (2%)                                
   Lymph Node, Mandibular                             (46)         (50)         (49)         (48)                                   
      Hemorrhage                                       1 (2%)       1 (2%)                    1 (2%)                                
      Hyperplasia, Lymphoid                            1 (2%)       1 (2%)                    1 (2%)                                
   Lymph Node, Mesenteric                             (50)         (50)         (49)         (49)                                   
      Hemorrhage                                       2 (4%)       1 (2%)       1 (2%)       1 (2%)                                
      Hyperplasia, Lymphoid                                         1 (2%)       2 (4%)                                             
   Lymph Node, Mediastinal                            (48)         (50)         (46)         (49)                                   
      Angiectasis                                                   1 (2%)                                                          
      Hemorrhage                                       1 (2%)       1 (2%)       3 (7%)       1 (2%)                                
   Spleen                                             (50)         (50)         (50)         (50)                                   
      Accessory Spleen                                 3 (6%)                    2 (4%)                                             
      Fibrosis                                        14 (28%)     13 (26%)     16 (32%)     17 (34%)                               
      Hematopoietic Cell Proliferation                                                        1 (2%)                                
      Hemorrhage                                                                              1 (2%)                                
      Necrosis                                         1 (2%)       1 (2%)       1 (2%)       4 (8%)                                
   Thymus                                             (50)         (49)         (48)         (50)                                   
      Hemorrhage                                       1 (2%)                    2 (4%)                                             
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   11                                                              
NTP Experiment-Test: 05181-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/20/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 15:30:26  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     CONTROL      200 PPM      600 PPM      1800 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
HEMATOPOIETIC SYSTEM - CONT                                                                                                         
      Hyperplasia, Lymphoid                                                      1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (50)         (50)         (50)         (50)                                   
      Galactocele                                      5 (10%)      3 (6%)       3 (6%)                                             
      Epithelium, Hyperplasia                          1 (2%)       1 (2%)                    1 (2%)                                
   Skin                                               (50)         (50)         (50)         (50)                                   
      Hyperkeratosis                                   5 (10%)                                                                      
      Hyperplasia                                      3 (6%)                                                                       
      Inflammation, Granulomatous                      1 (2%)                                 1 (2%)                                
      Inflammation, Suppurative                        5 (10%)      1 (2%)       2 (4%)       1 (2%)                                
      Necrosis                                                                   1 (2%)                                             
      Ulcer                                            4 (8%)       1 (2%)       4 (8%)       2 (4%)                                
      Epidermis, Cyst                                  1 (2%)       3 (6%)       2 (4%)       1 (2%)                                
      Prepuce, Ulcer                                                                          1 (2%)                                
      Subcutaneous Tissue, Hemorrhage                               1 (2%)       1 (2%)                                             
      Subcutaneous Tissue, Mineralization                                        1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (50)         (50)         (50)         (50)                                   
      Degeneration                                                                            1 (2%)                                
      Fibrosis                                                                   5 (10%)      1 (2%)                                
      Fracture                                                      1 (2%)                    1 (2%)                                
      Hemorrhage                                                                              1 (2%)                                
      Hyperostosis                                                                            1 (2%)                                
      Femur, Hyperplasia                                                         1 (2%)                                             
      Turbinate, Maxilla, Fracture                     1 (2%)                                                                       
      Turbinate, Maxilla, Hemorrhage                   1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (50)         (50)         (50)         (50)                                   
      Demyelination                                                 1 (2%)                                                          
      Developmental Malformation                       1 (2%)                                                                       
      Gliosis                                                                    1 (2%)                                             
      Hemorrhage                                       8 (16%)      5 (10%)      7 (14%)     11 (22%)                               
      Hydrocephalus                                    1 (2%)       1 (2%)                                                          
      Mineralization                                   1 (2%)                                                                       
      Necrosis                                         1 (2%)                                                                       
      Meninges, Hyperplasia                            1 (2%)                                                                       
      Ventricle, Hydrocephalus                         7 (14%)      7 (14%)      9 (18%)      4 (8%)                                
   Spinal Cord                                        (1)                       (1)          (1)                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   12                                                              
NTP Experiment-Test: 05181-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/20/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 15:30:26  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     CONTROL      200 PPM      600 PPM      1800 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
NERVOUS SYSTEM - CONT                                                                                                               
      Hemorrhage                                                                              1 (100%)                              
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Larynx                                             (50)         (49)         (50)         (49)                                   
      Foreign Body                                     3 (6%)       5 (10%)      3 (6%)       8 (16%)                               
      Inflammation, Suppurative                        3 (6%)       1 (2%)       2 (4%)       3 (6%)                                
      Epiglottis, Metaplasia, Squamous                                                        1 (2%)                                
      Epithelium, Hyperplasia                          1 (2%)       2 (4%)       1 (2%)       4 (8%)                                
      Epithelium, Metaplasia, Squamous                 2 (4%)                    3 (6%)       5 (10%)                               
      Glands, Inflammation, Suppurative                3 (6%)       1 (2%)       3 (6%)       2 (4%)                                
      Respiratory Epithelium, Epiglottis,                                                                                           
          Hyperplasia                                                                         1 (2%)                                
   Lung                                               (50)         (50)         (50)         (50)                                   
      Hemorrhage                                      16 (32%)     12 (24%)     17 (34%)     18 (36%)                               
      Alveolar Epithelium, Fibrosis                    1 (2%)       2 (4%)       1 (2%)       4 (8%)                                
      Alveolar Epithelium, Hyperplasia                 3 (6%)       4 (8%)       4 (8%)       6 (12%)                               
      Alveolar Epithelium, Infiltration Cellular,                                                                                   
           Histiocyte                                  7 (14%)      7 (14%)      8 (16%)     10 (20%)                               
      Alveolar Epithelium, Inflammation,                                                                                            
          Suppurative                                                                         1 (2%)                                
      Alveolar Epithelium, Mineralization                                        3 (6%)                                             
      Artery, Infiltration Cellular, Histiocyte        1 (2%)                                                                       
      Artery, Mineralization                           2 (4%)                    1 (2%)       3 (6%)                                
      Bronchiole, Hyperplasia                                                                 1 (2%)                                
      Bronchiole, Metaplasia, Squamous                              1 (2%)                                                          
      Mediastinum, Fibrosis                            1 (2%)                                                                       
   Nose                                               (50)         (49)         (49)         (50)                                   
      Foreign Body                                     6 (12%)      3 (6%)       5 (10%)      6 (12%)                               
      Hemorrhage                                       1 (2%)       1 (2%)       1 (2%)                                             
      Inflammation, Chronic                            1 (2%)                                                                       
      Inflammation, Suppurative                        8 (16%)      2 (4%)       8 (16%)      6 (12%)                               
      Glands, Dilatation, Focal                                     1 (2%)                                                          
      Goblet Cell, Respiratory Epithelium,                                                                                          
          Hypertrophy                                  3 (6%)                    1 (2%)       1 (2%)                                
      Nasolacrimal Duct, Inflammation, Suppurative     1 (2%)                    1 (2%)                                             
      Respiratory Epithelium, Hyperplasia              3 (6%)       1 (2%)       3 (6%)       3 (6%)                                
      Respiratory Epithelium, Metaplasia, Squamous     1 (2%)       1 (2%)                    2 (4%)                                
   Pleura                                             (2)          (1)          (2)                                                 
      Inflammation, Chronic                            1 (50%)      1 (100%)                                                        
   Trachea                                            (50)         (49)         (50)         (49)                                   
      Inflammation, Suppurative                                     1 (2%)                                                          
      Epithelium, Hyperplasia                                                                 1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   13                                                              
NTP Experiment-Test: 05181-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/20/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 15:30:26  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     CONTROL      200 PPM      600 PPM      1800 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                                          (3)          (2)                                    
      Cataract                                                                   1 (33%)                                            
      Anterior Chamber, Inflammation, Suppurative                                             1 (50%)                               
      Cornea, Inflammation, Chronic                                              1 (33%)                                            
      Cornea, Mineralization                                                     2 (67%)      1 (50%)                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (50)         (50)         (50)         (50)                                   
      Cyst                                             3 (6%)       3 (6%)       2 (4%)       5 (10%)                               
      Fibrosis                                         1 (2%)                                                                       
      Inflammation, Suppurative                                                               1 (2%)                                
      Metaplasia, Osseous                                                                     1 (2%)                                
      Nephropathy, Chronic                            48 (96%)     50 (100%)    50 (100%)    50 (100%)                              
      Thrombosis                                       1 (2%)                    1 (2%)       3 (6%)                                
      Cortex, Necrosis                                                           1 (2%)       3 (6%)                                
      Pelvis, Dilatation                               2 (4%)       1 (2%)                                                          
      Pelvis, Transitional Epithelium, Hyperplasia    16 (32%)     13 (26%)     16 (32%)     18 (36%)                               
      Pelvis, Transitional Epithelium,                                                                                              
          Inflammation, Suppurative                                 1 (2%)                    1 (2%)                                
      Renal Tubule, Degeneration                       1 (2%)                                                                       
      Renal Tubule, Hyperplasia                        7 (14%)      5 (10%)      6 (12%)      7 (14%)                               
      Renal Tubule, Inflammation, Suppurative          1 (2%)                                                                       
      Renal Tubule, Mineralization                     8 (16%)      7 (14%)      2 (4%)       5 (10%)                               
      Renal Tubule, Pigmentation, Hemosiderin                                                 1 (2%)                                
   Urinary Bladder                                    (50)         (50)         (49)         (50)                                   
      Hemorrhage                                       2 (4%)       1 (2%)                    2 (4%)                                
      Inflammation, Suppurative                        2 (4%)       1 (2%)                                                          
      Transitional Epithelium, Hyperplasia             2 (4%)       1 (2%)                    3 (6%)                                
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   14                                                              
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                             ----------              END OF REPORT             ----------                                           
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