Skip to Main Navigation
Skip to Page Content
Share This:
https://ntp.niehs.nih.gov/go/2010

TDMS Study 05181-04 Pathology Tables

NTP Experiment-Test: 05181-04         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:46:29

                                                           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: 05181-04         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:46:29  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        CONTROL      200 PPM      600 PPM      1800 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially In Study                          50           50           50           50                                     
  Early Deaths                                                                                                                      
    Accidently Killed                                  5            1            1                                                  
    Moribund Sacrifice                                13           10           20           13                                     
    Natural Death                                      3            6            3            5                                     
  Survivors                                                                                                                         
    Terminal Sacrifice                                29           33           26           32                                     
  Animals Examined Microscopically                    50           50           50           50                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Gallbladder                                        (45)         (44)         (45)         (44)                                   
      Degeneration, Hyaline                            1 (2%)                                                                       
      Inflammation                                     1 (2%)                                 1 (2%)                                
   Intestine Small, Ileum                             (46)         (45)         (46)         (46)                                   
      Diverticulum                                                                            1 (2%)                                
      Ulcer                                                                                   1 (2%)                                
   Liver                                              (50)         (50)         (50)         (48)                                   
      Angiectasis                                      1 (2%)       1 (2%)       1 (2%)                                             
      Basophilic Focus                                 1 (2%)                                 1 (2%)                                
      Clear Cell Focus                                              1 (2%)                    1 (2%)                                
      Eosinophilic Focus                               7 (14%)      9 (18%)      7 (14%)     11 (23%)                               
      Hematopoietic Cell Proliferation                              1 (2%)       2 (4%)       3 (6%)                                
      Hemorrhage                                       1 (2%)                                                                       
      Hepatodiaphragmatic Nodule                       1 (2%)                                 1 (2%)                                
      Inflammation, Chronic                            1 (2%)       1 (2%)       1 (2%)                                             
      Mixed Cell Focus                                              3 (6%)                    1 (2%)                                
      Necrosis                                         3 (6%)                                 7 (15%)                               
      Pigmentation                                     1 (2%)                                                                       
      Thrombosis                                                                              1 (2%)                                
      Vacuolization Cytoplasmic, Focal                              1 (2%)                                                          
      Bile Duct, Cyst                                  1 (2%)       1 (2%)                                                          
   Mesentery                                          (6)          (9)          (9)          (9)                                    
      Inflammation, Chronic                                                      1 (11%)                                            
      Fat, Hemorrhage                                                                         1 (11%)                               
      Fat, Necrosis                                    3 (50%)      6 (67%)      4 (44%)      7 (78%)                               
   Pancreas                                           (48)         (49)         (48)         (46)                                   
      Atrophy                                          1 (2%)       2 (4%)       1 (2%)       1 (2%)                                
      Basophilic Focus                                                                        1 (2%)                                
      Cytoplasmic Alteration                           1 (2%)       1 (2%)                                                          
      Hyperplasia                                                   1 (2%)       2 (4%)       2 (4%)                                
      Hypertrophy                                      1 (2%)       1 (2%)       1 (2%)       2 (4%)                                
      Inflammation                                                               1 (2%)                                             
      Duct, Cyst                                                    1 (2%)       1 (2%)                                             
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    2                                                              
NTP Experiment-Test: 05181-04         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:46:29  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        CONTROL      200 PPM      600 PPM      1800 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
   Stomach, Forestomach                               (50)         (49)         (49)         (47)                                   
      Angiectasis                                                                             1 (2%)                                
      Infiltration Cellular, Mast Cell                 1 (2%)                                                                       
      Inflammation                                                                            1 (2%)                                
      Ulcer                                            3 (6%)       1 (2%)                    2 (4%)                                
      Epithelium, Hyperplasia                          2 (4%)                    1 (2%)       1 (2%)                                
   Stomach, Glandular                                 (49)         (48)         (48)         (47)                                   
      Erosion                                          2 (4%)                    1 (2%)       2 (4%)                                
      Infiltration Cellular, Mast Cell                 1 (2%)                                                                       
      Inflammation, Suppurative                        1 (2%)       1 (2%)                                                          
      Mineralization                                   1 (2%)                                                                       
      Ulcer                                                         1 (2%)                                                          
      Epithelium, Hyperplasia                                                                 1 (2%)                                
   Tooth                                                                        (1)                                                 
      Developmental Malformation                                                 1 (100%)                                           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Blood Vessel                                       (1)                                    (1)                                    
      Inflammation                                                                            1 (100%)                              
      Mineralization                                   1 (100%)                                                                     
   Heart                                              (50)         (50)         (50)         (48)                                   
      Cardiomyopathy                                  17 (34%)     28 (56%)     25 (50%)     22 (46%)                               
      Hemorrhage                                       1 (2%)                                                                       
      Mineralization                                   1 (2%)                                 1 (2%)                                
      Artery, Inflammation                             1 (2%)                    2 (4%)       1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (50)         (50)         (50)         (46)                                   
      Hematopoietic Cell Proliferation                                           1 (2%)       1 (2%)                                
      Hyperplasia                                      2 (4%)       1 (2%)                                                          
      Hypertrophy                                      3 (6%)       4 (8%)       5 (10%)      3 (7%)                                
      Necrosis                                         1 (2%)                                 1 (2%)                                
      Capsule, Hyperplasia                             1 (2%)       1 (2%)       1 (2%)                                             
   Adrenal Medulla                                    (49)         (49)         (50)         (45)                                   
      Hyperplasia                                      4 (8%)       8 (16%)      1 (2%)       1 (2%)                                
      Necrosis                                         1 (2%)                                 1 (2%)                                
   Islets, Pancreatic                                 (48)         (49)         (47)         (46)                                   
      Hyperplasia                                                                             1 (2%)                                
   Parathyroid Gland                                  (30)         (33)         (33)         (34)                                   
      Cyst                                                                       1 (3%)                                             
   Pituitary Gland                                    (47)         (48)         (48)         (48)                                   
      Hyperplasia                                      1 (2%)                                                                       
      Pars Distalis, Cyst                                                                     1 (2%)                                
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    3                                                              
NTP Experiment-Test: 05181-04         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:46:29  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        CONTROL      200 PPM      600 PPM      1800 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ENDOCRINE SYSTEM - CONT                                                                                                             
      Pars Distalis, Hyperplasia                      14 (30%)     12 (25%)     16 (33%)     20 (42%)                               
      Pars Intermedia, Hyperplasia                     1 (2%)       3 (6%)                                                          
   Thyroid Gland                                      (50)         (50)         (49)         (47)                                   
      Angiectasis                                      1 (2%)                                                                       
      Inflammation                                     1 (2%)                                                                       
      C-Cell, Hyperplasia                                                                     1 (2%)                                
      Follicular Cell, Hyperplasia                    14 (28%)     10 (20%)     15 (31%)     10 (21%)                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   Peritoneum                                                                                (1)                                    
      Inflammation, Suppurative                                                               1 (100%)                              
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Clitoral Gland                                     (38)         (40)         (43)         (41)                                   
      Inflammation                                     1 (3%)       1 (3%)                                                          
   Ovary                                              (49)         (50)         (50)         (46)                                   
      Amyloid Deposition                               1 (2%)                                                                       
      Angiectasis                                      3 (6%)                                 1 (2%)                                
      Atrophy                                          8 (16%)      5 (10%)      9 (18%)      9 (20%)                               
      Cyst                                            19 (39%)     15 (30%)     14 (28%)     17 (37%)                               
      Hyperplasia                                      1 (2%)                                                                       
      Inflammation                                                               1 (2%)                                             
      Pigmentation, Hemosiderin                                                  1 (2%)                                             
      Artery, Inflammation                                                       1 (2%)                                             
      Corpus Luteum, Hyperplasia                                                 1 (2%)                                             
      Granulosa Cell, Hyperplasia                      1 (2%)                                                                       
      Interstitial Cell, Hyperplasia                                1 (2%)                    1 (2%)                                
   Uterus                                             (49)         (50)         (49)         (49)                                   
      Adenomyosis                                                                             1 (2%)                                
      Angiectasis                                      1 (2%)       2 (4%)       1 (2%)       3 (6%)                                
      Hydrometra                                       3 (6%)       5 (10%)                  11 (22%)                               
      Hyperplasia, Cystic                             41 (84%)     41 (82%)     44 (90%)     41 (84%)                               
      Inflammation, Suppurative                        1 (2%)                                 2 (4%)                                
      Thrombosis                                                    1 (2%)                    1 (2%)                                
      Endometrium, Hyperplasia                         1 (2%)       1 (2%)                    1 (2%)                                
      Serosa, Cyst                                                               1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    4                                                              
NTP Experiment-Test: 05181-04         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:46:29  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        CONTROL      200 PPM      600 PPM      1800 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (49)         (50)         (49)         (46)                                   
      Angiectasis                                      1 (2%)                                                                       
      Hyperplasia                                                                4 (8%)       2 (4%)                                
      Hyperplasia, Histiocytic                         2 (4%)                                                                       
      Infiltration Cellular, Mast Cell                              1 (2%)                                                          
   Lymph Node                                         (5)          (4)          (4)          (2)                                    
      Degeneration, Cystic                                          1 (25%)                                                         
      Hemorrhage                                                    1 (25%)                                                         
      Iliac, Hyperplasia                               2 (40%)                   1 (25%)                                            
      Lumbar, Angiectasis                                                                     1 (50%)                               
      Lumbar, Hyperplasia                              1 (20%)                                                                      
      Renal, Hyperplasia                                                         1 (25%)                                            
   Lymph Node, Bronchial                              (36)         (41)         (39)         (41)                                   
      Hyperplasia                                      1 (3%)       3 (7%)       6 (15%)      2 (5%)                                
   Lymph Node, Mandibular                             (40)         (41)         (39)         (41)                                   
      Hyperplasia                                      5 (13%)      2 (5%)       4 (10%)      3 (7%)                                
      Pigmentation, Hemosiderin                                                               1 (2%)                                
   Lymph Node, Mesenteric                             (45)         (46)         (47)         (45)                                   
      Angiectasis                                                   1 (2%)       1 (2%)                                             
      Hematopoietic Cell Proliferation                              1 (2%)                                                          
      Hyperplasia                                      2 (4%)       3 (7%)       5 (11%)      3 (7%)                                
   Lymph Node, Mediastinal                            (37)         (36)         (41)         (38)                                   
      Hematopoietic Cell Proliferation                                                        1 (3%)                                
      Hyperplasia                                      3 (8%)                    4 (10%)      1 (3%)                                
   Spleen                                             (49)         (50)         (49)         (46)                                   
      Angiectasis                                      1 (2%)                                                                       
      Hematopoietic Cell Proliferation                10 (20%)      8 (16%)     10 (20%)      8 (17%)                               
      Hyperplasia, Lymphoid                            4 (8%)       1 (2%)       2 (4%)       2 (4%)                                
      Infiltration Cellular, Mast Cell                              1 (2%)                                                          
   Thymus                                             (40)         (44)         (38)         (44)                                   
      Amyloid Deposition                               1 (3%)                                                                       
      Angiectasis                                                                             1 (2%)                                
      Atrophy                                          5 (13%)      3 (7%)       3 (8%)       2 (5%)                                
      Hyperplasia, Lymphoid                            1 (3%)       1 (2%)       1 (3%)       2 (5%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (48)         (49)         (50)         (50)                                   
      Hyperplasia                                      1 (2%)       1 (2%)                                                          
   Skin                                               (49)         (50)         (50)         (50)                                   
      Inflammation, Suppurative                                     1 (2%)                                                          
      Epidermis, Hyperplasia                                                     1 (2%)                                             
      Subcutaneous Tissue, Angiectasis                                                        1 (2%)                                
      Subcutaneous Tissue, Edema                       1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    5                                                              
NTP Experiment-Test: 05181-04         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:46:29  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        CONTROL      200 PPM      600 PPM      1800 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (50)         (50)         (50)         (49)                                   
      Arthrosis                                                                               2 (4%)                                
      Fibrous Osteodystrophy                          19 (38%)     23 (46%)     16 (32%)     15 (31%)                               
      Cranium, Fracture                                                          1 (2%)                                             
      Vertebra, Fracture                                            1 (2%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (50)         (50)         (50)         (49)                                   
      Hemorrhage                                                    1 (2%)       1 (2%)                                             
      Hydrocephalus                                                              1 (2%)                                             
      Meninges, Infiltration Cellular, Mononuclear                                                                                  
          Cell                                         1 (2%)       2 (4%)       1 (2%)       3 (6%)                                
   Spinal Cord                                                     (1)          (1)                                                 
      Degeneration                                                               1 (100%)                                           
      Hemorrhage                                                    1 (100%)                                                        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Lung                                               (50)         (50)         (50)         (49)                                   
      Hemorrhage                                                    1 (2%)                                                          
      Infiltration Cellular, Histiocyte                2 (4%)       3 (6%)       1 (2%)       2 (4%)                                
      Inflammation, Chronic, Focal                     2 (4%)                    2 (4%)                                             
      Alveolar Epithelium, Hyperplasia                 2 (4%)       4 (8%)       2 (4%)       1 (2%)                                
      Mediastinum, Inflammation                                                  1 (2%)                                             
      Perivascular, Infiltration Cellular,                                                                                          
          Mononuclear Cell                                          1 (2%)       3 (6%)                                             
   Nose                                               (50)         (50)         (48)         (49)                                   
      Inflammation, Suppurative                                                  2 (4%)                                             
      Nasolacrimal Duct, Inflammation, Suppurative     1 (2%)                    1 (2%)                                             
      Olfactory Epithelium, Atrophy, Focal                          3 (6%)       1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    6                                                              
NTP Experiment-Test: 05181-04         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:46:29  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        CONTROL      200 PPM      600 PPM      1800 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (50)         (49)         (49)         (46)                                   
      Amyloid Deposition                               1 (2%)       2 (4%)                                                          
      Glomerulosclerosis                               1 (2%)                                                                       
      Hydronephrosis                                                1 (2%)       1 (2%)                                             
      Hyperplasia, Lymphoid                            2 (4%)       1 (2%)                                                          
      Metaplasia, Osseous                              1 (2%)       3 (6%)       2 (4%)                                             
      Nephropathy                                     17 (34%)     17 (35%)     19 (39%)     13 (28%)                               
      Pigmentation                                     1 (2%)                                                                       
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    7                                                              
NTP Experiment-Test: 05181-04         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:46:29  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          CONTROL      200 PPM      600 PPM      1800 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially In Study                          50           50           50           50                                     
  Early Deaths                                                                                                                      
    Natural Death                                      7            7            4           14                                     
    Moribund Sacrifice                                11           12           18           24                                     
  Survivors                                                                                                                         
    Terminal Sacrifice                                32           31           28           12                                     
  Animals Examined Microscopically                    50           50           50           50                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Gallbladder                                        (42)         (46)         (44)         (38)                                   
      Degeneration, Hyaline                            1 (2%)       1 (2%)                                                          
      Inflammation                                     1 (2%)       1 (2%)                                                          
      Epithelium, Hyperplasia                          1 (2%)                                 1 (3%)                                
   Intestine Large, Cecum                             (47)         (47)         (46)         (40)                                   
      Muscularis, Hyperplasia                                                                 1 (3%)                                
   Intestine Small, Duodenum                          (44)         (45)         (45)         (40)                                   
      Ulcer                                                         1 (2%)                                                          
      Epithelium, Hyperplasia                          1 (2%)                                                                       
   Intestine Small, Jejunum                           (45)         (45)         (46)         (37)                                   
      Peyer's Patch, Hyperplasia                                    1 (2%)       1 (2%)                                             
   Intestine Small, Ileum                             (46)         (46)         (46)         (40)                                   
      Peyer's Patch, Hyperplasia                                                 1 (2%)                                             
      Peyer's Patch, Inflammation                                                1 (2%)                                             
   Liver                                              (50)         (50)         (50)         (50)                                   
      Angiectasis                                                                             1 (2%)                                
      Basophilic Focus                                 1 (2%)                    1 (2%)                                             
      Clear Cell Focus                                                           2 (4%)       2 (4%)                                
      Congestion                                       2 (4%)                                                                       
      Degeneration, Fatty, Focal                       1 (2%)                                                                       
      Eosinophilic Focus                              11 (22%)      8 (16%)     10 (20%)      5 (10%)                               
      Hematopoietic Cell Proliferation                              1 (2%)       1 (2%)                                             
      Infiltration Cellular, Histiocyte                1 (2%)                                                                       
      Inflammation, Chronic                            1 (2%)                    1 (2%)                                             
      Mixed Cell Focus                                 1 (2%)       1 (2%)                                                          
      Necrosis                                         8 (16%)      5 (10%)      6 (12%)      4 (8%)                                
      Centrilobular, Necrosis                                       1 (2%)                                                          
   Mesentery                                          (3)          (3)          (2)                                                 
      Fat, Necrosis                                    2 (67%)      1 (33%)      1 (50%)                                            
   Pancreas                                           (48)         (48)         (46)         (48)                                   
      Amyloid Deposition                               1 (2%)                                                                       
      Atrophy                                          1 (2%)       4 (8%)                    1 (2%)                                
      Basophilic Focus                                                           1 (2%)                                             
      Cytoplasmic Alteration                           1 (2%)                                                                       
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    8                                                              
NTP Experiment-Test: 05181-04         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:46:29  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          CONTROL      200 PPM      600 PPM      1800 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Hypertrophy                                                   1 (2%)                    1 (2%)                                
   Salivary Glands                                    (50)         (50)         (50)         (50)                                   
      Basophilic Focus                                                           1 (2%)                                             
   Stomach, Forestomach                               (49)         (50)         (48)         (49)                                   
      Hyperplasia                                                                1 (2%)                                             
      Ulcer                                            1 (2%)                                 1 (2%)                                
      Epithelium, Hyperplasia                          1 (2%)                                 1 (2%)                                
   Stomach, Glandular                                 (48)         (48)         (46)         (48)                                   
      Degeneration, Hyaline                                                                   1 (2%)                                
      Erosion                                                                    1 (2%)       3 (6%)                                
      Infiltration Cellular, Mast Cell                                           1 (2%)                                             
      Inflammation, Suppurative                                                               2 (4%)                                
      Mineralization                                   1 (2%)                                                                       
      Epithelium, Hyperplasia                                       2 (4%)                                                          
   Tooth                                                           (1)          (2)                                                 
      Developmental Malformation                                    1 (100%)     1 (50%)                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Blood Vessel                                                                 (1)                                                 
      Aorta, Inflammation                                                        1 (100%)                                           
      Aorta, Pigmentation, Hemosiderin                                           1 (100%)                                           
   Heart                                              (49)         (50)         (50)         (50)                                   
      Cardiomyopathy                                  28 (57%)     36 (72%)     35 (70%)     14 (28%)                               
      Hyperplasia, Atypical                                                      1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (48)         (50)         (49)         (50)                                   
      Hemorrhage                                                                 1 (2%)                                             
      Hyperplasia                                      7 (15%)      5 (10%)      6 (12%)      2 (4%)                                
      Hypertrophy                                     20 (42%)     24 (48%)     19 (39%)     10 (20%)                               
      Capsule, Hyperplasia                                                       1 (2%)       1 (2%)                                
   Adrenal Medulla                                    (48)         (50)         (49)         (50)                                   
      Hyperplasia                                                   2 (4%)                    1 (2%)                                
   Islets, Pancreatic                                 (48)         (48)         (46)         (48)                                   
      Hyperplasia                                      6 (13%)      2 (4%)       3 (7%)       2 (4%)                                
   Pituitary Gland                                    (45)         (47)         (45)         (47)                                   
      Pars Distalis, Cyst                              5 (11%)                   1 (2%)       1 (2%)                                
      Pars Distalis, Hyperplasia                       2 (4%)       2 (4%)       1 (2%)                                             
   Thyroid Gland                                      (49)         (50)         (49)         (49)                                   
      Follicular Cell, Hyperplasia                    16 (33%)     12 (24%)      9 (18%)      3 (6%)                                
____________________________________________________________________________________________________________________________________
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    9                                                              
NTP Experiment-Test: 05181-04         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:46:29  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          CONTROL      200 PPM      600 PPM      1800 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Coagulating Gland                                                            (1)          (1)                                    
      Inflammation, Suppurative                                                  1 (100%)                                           
   Epididymis                                         (49)         (50)         (50)         (50)                                   
      Granuloma Sperm                                               1 (2%)       1 (2%)                                             
      Inflammation                                                  1 (2%)                    1 (2%)                                
   Penis                                              (1)          (2)          (2)          (27)                                   
      Congestion                                                                              1 (4%)                                
      Inflammation, Suppurative                                     1 (50%)      1 (50%)      9 (33%)                               
   Preputial Gland                                    (50)         (49)         (50)         (48)                                   
      Cyst                                             5 (10%)      3 (6%)       1 (2%)       1 (2%)                                
      Inflammation                                     8 (16%)     16 (33%)      9 (18%)      9 (19%)                               
      Duct, Hyperplasia                                             1 (2%)                                                          
   Prostate                                           (48)         (43)         (44)         (47)                                   
      Inflammation, Suppurative                        3 (6%)       4 (9%)       4 (9%)      14 (30%)                               
   Seminal Vesicle                                    (48)         (48)         (46)         (46)                                   
      Angiectasis                                                                1 (2%)                                             
      Inflammation, Chronic                                         2 (4%)                                                          
      Inflammation, Suppurative                                                               1 (2%)                                
   Testes                                             (50)         (50)         (50)         (50)                                   
      Atrophy                                          5 (10%)      3 (6%)       2 (4%)       2 (4%)                                
      Mineralization                                                             1 (2%)                                             
      Interstitial Cell, Hyperplasia                   1 (2%)       1 (2%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (49)         (50)         (49)         (50)                                   
      Angiectasis                                      1 (2%)                                                                       
      Hyperplasia                                      5 (10%)      6 (12%)      7 (14%)     14 (28%)                               
      Infiltration Cellular, Mast Cell                                           2 (4%)                                             
   Lymph Node                                         (1)          (4)          (4)          (5)                                    
      Iliac, Hyperplasia                                            3 (75%)      3 (75%)      5 (100%)                              
      Renal, Hyperplasia                               1 (100%)     1 (25%)                                                         
   Lymph Node, Bronchial                              (33)         (32)         (36)         (26)                                   
      Hyperplasia                                      2 (6%)       3 (9%)       1 (3%)                                             
   Lymph Node, Mandibular                             (42)         (40)         (43)         (35)                                   
      Hyperplasia                                      4 (10%)      1 (3%)                                                          
   Lymph Node, Mesenteric                             (47)         (48)         (46)         (41)                                   
      Angiectasis                                      2 (4%)       1 (2%)       1 (2%)                                             
      Congestion                                                    1 (2%)                                                          
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   10                                                              
NTP Experiment-Test: 05181-04         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:46:29  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          CONTROL      200 PPM      600 PPM      1800 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
HEMATOPOIETIC SYSTEM - CONT                                                                                                         
      Hematopoietic Cell Proliferation                 2 (4%)       2 (4%)                                                          
      Hyperplasia                                      3 (6%)       1 (2%)       3 (7%)       1 (2%)                                
   Lymph Node, Mediastinal                            (36)         (40)         (39)         (32)                                   
      Hyperplasia                                                   2 (5%)       1 (3%)                                             
   Spleen                                             (48)         (49)         (47)         (49)                                   
      Atrophy                                                                                 1 (2%)                                
      Hematopoietic Cell Proliferation                 9 (19%)     13 (27%)     14 (30%)     18 (37%)                               
      Hyperplasia, Lymphoid                            5 (10%)      2 (4%)       3 (6%)                                             
   Thymus                                             (35)         (37)         (34)         (36)                                   
      Atrophy                                          2 (6%)       2 (5%)       4 (12%)      9 (25%)                               
      Hyperplasia, Lymphoid                                                      1 (3%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Skin                                               (47)         (50)         (48)         (50)                                   
      Inflammation, Suppurative                                     1 (2%)       2 (4%)                                             
      Prepuce, Inflammation, Suppurative               7 (15%)      7 (14%)      7 (15%)     18 (36%)                               
      Subcutaneous Tissue, Infiltration Cellular,                                                                                   
           Mast Cell                                                1 (2%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (50)         (50)         (50)         (50)                                   
      Fibrous Osteodystrophy                           3 (6%)       2 (4%)       2 (4%)       1 (2%)                                
      Synovial Tissue, Inflammation, Chronic                                     1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Larynx                                             (48)         (49)         (48)         (48)                                   
      Epiglottis, Metaplasia, Squamous                              2 (4%)       1 (2%)                                             
   Lung                                               (50)         (50)         (50)         (50)                                   
      Hemorrhage                                                                 1 (2%)                                             
      Infiltration Cellular, Histiocyte                5 (10%)      7 (14%)      7 (14%)      1 (2%)                                
      Inflammation, Chronic, Focal                                  2 (4%)       1 (2%)                                             
      Pigmentation, Hemosiderin                                     1 (2%)                                                          
      Thrombosis                                                                              1 (2%)                                
      Alveolar Epithelium, Hyperplasia                 6 (12%)      1 (2%)       1 (2%)       1 (2%)                                
      Perivascular, Infiltration Cellular,                                                                                          
          Mononuclear Cell                                          1 (2%)                                                          
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   11                                                              
NTP Experiment-Test: 05181-04         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 11:46:29  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          CONTROL      200 PPM      600 PPM      1800 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
RESPIRATORY SYSTEM - CONT                                                                                                           
   Nose                                               (48)         (50)         (50)         (50)                                   
      Fibrosis                                                                   1 (2%)                                             
      Inflammation, Suppurative                                     3 (6%)       2 (4%)       4 (8%)                                
      Nasolacrimal Duct, Inflammation, Suppurative     3 (6%)       1 (2%)                    2 (4%)                                
      Olfactory Epithelium, Atrophy, Focal             2 (4%)       1 (2%)       4 (8%)       1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (49)         (50)         (49)         (50)                                   
      Glomerulosclerosis                               2 (4%)                                                                       
      Hydronephrosis                                   3 (6%)       3 (6%)       5 (10%)     18 (36%)                               
      Inflammation, Suppurative                        3 (6%)       5 (10%)      5 (10%)     18 (36%)                               
      Metaplasia, Osseous                                           1 (2%)       2 (4%)       3 (6%)                                
      Mineralization                                                             1 (2%)                                             
      Nephropathy                                     31 (63%)     40 (80%)     33 (67%)     14 (28%)                               
      Cortex, Cyst                                     2 (4%)       1 (2%)                    1 (2%)                                
      Pelvis, Necrosis                                                                        3 (6%)                                
      Renal Tubule, Hyperplasia                        2 (4%)       2 (4%)       1 (2%)                                             
      Renal Tubule, Hypertrophy                                                               1 (2%)                                
      Renal Tubule, Necrosis                                                                  2 (4%)                                
   Ureter                                                          (1)                                                              
      Inflammation, Suppurative                                     1 (100%)                                                        
   Urethra                                                         (3)          (1)          (14)                                   
      Inflammation, Suppurative                                     3 (100%)     1 (100%)    12 (86%)                               
      Necrosis                                                                   1 (100%)     5 (36%)                               
   Urinary Bladder                                    (48)         (49)         (46)         (48)                                   
      Calculus Gross Observation                                                              3 (6%)                                
      Calculus Micro Observation Only                               1 (2%)                    2 (4%)                                
      Inflammation, Suppurative                        3 (6%)       6 (12%)      6 (13%)     16 (33%)                               
      Transitional Epithelium, Hyperplasia                          1 (2%)       1 (2%)       5 (10%)                               
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   12                                                              
                             ------------------------------------------------------------                                           
                             ----------              END OF REPORT             ----------                                           
                             ------------------------------------------------------------