Skip to Main Navigation
Skip to Page Content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it's official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you're on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Share This:
https://ntp.niehs.nih.gov/go/12888

TDMS Study 90004-06 Pathology Tables

NTP Experiment-Test: 90004-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                PROPYLENE GLYCOL MONO-T-BUTYL ETHER                            Date: 01/02/02
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 08:46:38

                                                           FINAL/MICE




       Facility:  Battelle Northwest

       Chemical CAS #:  57018-52-7

       Lock Date:  12/11/00

       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: 90004-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                PROPYLENE GLYCOL MONO-T-BUTYL ETHER                            Date: 01/02/02    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 08:46:38    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE FEMALE                        CONTROL      75 PPM       300 PPM      1200 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
DISPOSITION SUMMARY                                                                                                                 
                                                                                                                                    
  Animals Initially In Study                          50           50           50           50                                     
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                 8           10            6            4                                     
    Natural Death                                      3            3            2            6                                     
    Accidently Killed                                               1                         1                                     
  Survivors                                                                                                                         
    Terminal Sacrifice                                39           36           41           38                                     
    Natural Death                                                                1            1                                     
                                                                                                                                    
  Animals Examined Microscopically                    50           50           50           49                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Gallbladder                                        (40)         (39)         (43)         (33)                                   
      Cyst                                             1 (3%)                                                                       
   Intestine Large, Colon                             (48)         (49)         (50)         (48)                                   
      Infiltration Cellular, Mixed Cell                                                       1 (2%)                                
   Intestine Large, Rectum                            (48)         (49)         (50)         (48)                                   
      Necrosis                                                                                1 (2%)                                
   Intestine Large, Cecum                             (49)         (48)         (49)         (46)                                   
      Necrosis                                                                   2 (4%)                                             
   Intestine Small, Duodenum                          (49)         (47)         (50)         (46)                                   
      Infiltration Cellular, Mixed Cell                                                       1 (2%)                                
      Epithelium, Hyperplasia                                                    1 (2%)                                             
   Intestine Small, Jejunum                           (49)         (48)         (48)         (47)                                   
      Infiltration Cellular, Mixed Cell                                          1 (2%)                                             
      Inflammation, Suppurative                                                               1 (2%)                                
      Necrosis                                                                                1 (2%)                                
   Intestine Small, Ileum                             (49)         (48)         (48)         (45)                                   
      Hyperplasia                                      1 (2%)                                                                       
      Infiltration Cellular, Mixed Cell                2 (4%)       1 (2%)       3 (6%)       1 (2%)                                
      Necrosis                                                                                2 (4%)                                
      Epithelium, Hyperplasia                          1 (2%)                                                                       
   Liver                                              (49)         (50)         (50)         (49)                                   
      Angiectasis                                                                1 (2%)                                             
      Basophilic Focus                                 3 (6%)       4 (8%)       4 (8%)       2 (4%)                                
      Clear Cell Focus                                 4 (8%)       4 (8%)       6 (12%)      5 (10%)                               
      Eosinophilic Focus                              11 (22%)     10 (20%)      9 (18%)     27 (55%)                               
      Fatty Change                                     2 (4%)       1 (2%)       1 (2%)       1 (2%)                                
      Fatty Change, Focal                                           1 (2%)                                                          
      Hematopoietic Cell Proliferation                                           1 (2%)                                             
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page    2                                                              
                                                                                                                                   
NTP Experiment-Test: 90004-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                PROPYLENE GLYCOL MONO-T-BUTYL ETHER                            Date: 01/02/02    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 08:46:38    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE FEMALE                        CONTROL      75 PPM       300 PPM      1200 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Infarct                                                                    1 (2%)                                             
      Inflammation, Granulomatous                     23 (47%)      9 (18%)     17 (34%)     12 (24%)                               
      Tension Lipidosis                                4 (8%)       3 (6%)       6 (12%)      4 (8%)                                
      Thrombosis                                                                 1 (2%)                                             
      Bile Duct, Cyst                                  1 (2%)                                                                       
      Bile Duct, Hyperplasia                                        1 (2%)       1 (2%)                                             
      Centrilobular, Necrosis                                       3 (6%)                                                          
      Hepatocyte, Mitotic Alteration                                1 (2%)                                                          
   Mesentery                                          (17)         (21)         (13)         (2)                                    
      Infiltration Cellular, Mast Cell                 1 (6%)                                                                       
      Fat, Congestion                                  1 (6%)                                                                       
      Fat, Necrosis                                   14 (82%)     19 (90%)     12 (92%)      2 (100%)                              
   Oral Mucosa                                        (1)                                                                           
      Inflammation                                     1 (100%)                                                                     
   Pancreas                                           (49)         (50)         (50)         (48)                                   
      Atrophy                                          1 (2%)                    2 (4%)                                             
      Basophilic Focus                                 1 (2%)       1 (2%)       1 (2%)                                             
      Duct, Cyst                                                                 1 (2%)                                             
   Salivary Glands                                    (50)         (50)         (50)         (49)                                   
      Atrophy                                                                                 1 (2%)                                
   Stomach, Forestomach                               (49)         (50)         (50)         (48)                                   
      Hyperplasia, Squamous                            3 (6%)       5 (10%)      1 (2%)       6 (13%)                               
      Infiltration Cellular, Mast Cell                                           1 (2%)                                             
      Infiltration Cellular, Mixed Cell                1 (2%)                                                                       
      Inflammation                                     2 (4%)       5 (10%)      2 (4%)       6 (13%)                               
      Ulcer                                            2 (4%)                    1 (2%)       4 (8%)                                
   Stomach, Glandular                                 (49)         (48)         (50)         (48)                                   
      Mineralization                                   2 (4%)       1 (2%)       1 (2%)       1 (2%)                                
   Tooth                                              (50)         (50)         (50)         (49)                                   
      Inflammation, Chronic Active                     1 (2%)       2 (4%)       1 (2%)       7 (14%)                               
      Malformation                                     1 (2%)       1 (2%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Blood Vessel                                                                 (2)                                                 
      Inflammation, Chronic                                                      1 (50%)                                            
   Heart                                              (50)         (50)         (50)         (49)                                   
      Cardiomyopathy                                   5 (10%)      4 (8%)       8 (16%)      3 (6%)                                
      Inflammation, Chronic                                         1 (2%)                                                          
      Mineralization                                   1 (2%)       1 (2%)                                                          
      Thrombosis                                                                              1 (2%)                                
      Artery, Inflammation, Chronic Active             1 (2%)                                                                       
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page    3                                                              
                                                                                                                                   
NTP Experiment-Test: 90004-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                PROPYLENE GLYCOL MONO-T-BUTYL ETHER                            Date: 01/02/02    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 08:46:38    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE FEMALE                        CONTROL      75 PPM       300 PPM      1200 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
CARDIOVASCULAR SYSTEM - CONT                                                                                                        
      Endocardium, Hyperplasia                                      1 (2%)                                                          
      Valve, Inflammation, Suppurative                              1 (2%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (49)         (50)         (50)         (48)                                   
      Hyperplasia                                      8 (16%)      3 (6%)       3 (6%)       4 (8%)                                
      Hypertrophy                                      7 (14%)      7 (14%)      1 (2%)       2 (4%)                                
      Necrosis                                         1 (2%)       1 (2%)                                                          
      Vacuolization Cytoplasmic                                     3 (6%)       3 (6%)                                             
   Adrenal Medulla                                    (47)         (49)         (50)         (48)                                   
      Hyperplasia                                      2 (4%)       4 (8%)       1 (2%)       3 (6%)                                
      Hypertrophy                                                                             1 (2%)                                
      Necrosis                                         1 (2%)                                                                       
   Islets, Pancreatic                                 (49)         (50)         (50)         (48)                                   
      Hyperplasia                                      1 (2%)                                 1 (2%)                                
   Pituitary Gland                                    (48)         (49)         (47)         (46)                                   
      Pars Distalis, Angiectasis                       1 (2%)                    1 (2%)       1 (2%)                                
      Pars Distalis, Hyperplasia                      16 (33%)     11 (22%)     16 (34%)     11 (24%)                               
   Thyroid Gland                                      (49)         (50)         (50)         (48)                                   
      Follicular Cell, Hyperplasia                     2 (4%)       1 (2%)       3 (6%)       1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   Peritoneum                                                      (1)          (2)                                                 
      Inflammation, Chronic, Suppurative                            1 (100%)                                                        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Clitoral Gland                                     (42)         (43)         (48)         (45)                                   
      Inflammation, Chronic                                         1 (2%)                                                          
   Ovary                                              (50)         (49)         (49)         (48)                                   
      Angiectasis                                      1 (2%)       1 (2%)                                                          
      Atrophy                                                                                 1 (2%)                                
      Cyst                                            12 (24%)     12 (24%)     12 (24%)     11 (23%)                               
      Inflammation, Chronic Active                                  1 (2%)                                                          
      Thrombosis                                                                 1 (2%)                                             
   Uterus                                             (50)         (50)         (50)         (48)                                   
      Angiectasis                                      3 (6%)       1 (2%)       4 (8%)       2 (4%)                                
      Inflammation, Suppurative                                     1 (2%)       2 (4%)       2 (4%)                                
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page    4                                                              
                                                                                                                                   
NTP Experiment-Test: 90004-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                PROPYLENE GLYCOL MONO-T-BUTYL ETHER                            Date: 01/02/02    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 08:46:38    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE FEMALE                        CONTROL      75 PPM       300 PPM      1200 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
GENITAL SYSTEM - CONT                                                                                                               
      Thrombosis                                                    2 (4%)                                                          
      Endometrium, Fibrosis                            1 (2%)                                                                       
      Endometrium, Hyperplasia, Cystic                46 (92%)     48 (96%)     48 (96%)     45 (94%)                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (49)         (50)         (50)         (48)                                   
      Thrombosis                                                                              1 (2%)                                
   Lymph Node                                         (4)          (8)          (6)          (2)                                    
      Angiectasis                                                   2 (25%)                                                         
      Ectasia                                                                    1 (17%)                                            
      Lumbar, Angiectasis                              1 (25%)                                                                      
      Renal, Angiectasis                               1 (25%)                                                                      
      Renal, Ectasia                                   1 (25%)                                                                      
   Lymph Node, Mandibular                             (44)         (45)         (45)         (34)                                   
      Hyperplasia, Lymphoid                                                                   1 (3%)                                
      Infiltration Cellular, Plasma Cell                                                      1 (3%)                                
   Lymph Node, Mesenteric                             (48)         (48)         (48)         (48)                                   
      Angiectasis                                      1 (2%)       2 (4%)       2 (4%)       1 (2%)                                
      Infiltration Cellular, Plasma Cell                            1 (2%)                                                          
      Inflammation, Granulomatous                                                1 (2%)                                             
      Inflammation, Suppurative                                                               1 (2%)                                
   Lymph Node, Mediastinal                            (40)         (41)         (41)         (31)                                   
      Hemorrhage                                       1 (3%)                                                                       
   Spleen                                             (49)         (50)         (50)         (48)                                   
      Fibrosis                                                      1 (2%)                                                          
      Hematopoietic Cell Proliferation                 4 (8%)       4 (8%)       2 (4%)       3 (6%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Skin                                               (50)         (50)         (50)         (49)                                   
      Hyperplasia, Squamous                            1 (2%)                                                                       
      Infiltration Cellular, Mixed Cell                1 (2%)       3 (6%)       2 (4%)                                             
      Inflammation, Acute                                                                     1 (2%)                                
      Inflammation, Chronic Active                                                            1 (2%)                                
      Subcutaneous Tissue, Inflammation, Acute                      1 (2%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (50)         (50)         (50)         (49)                                   
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page    5                                                              
                                                                                                                                   
NTP Experiment-Test: 90004-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                PROPYLENE GLYCOL MONO-T-BUTYL ETHER                            Date: 01/02/02    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 08:46:38    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE FEMALE                        CONTROL      75 PPM       300 PPM      1200 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
MUSCULOSKELETAL SYSTEM - CONT                                                                                                       
      Synovial Tissue, Hyperplasia                                               1 (2%)                                             
   Skeletal Muscle                                    (1)          (2)                                                              
      Hemorrhage                                       1 (100%)                                                                     
      Inflammation, Acute                                           1 (50%)                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (50)         (50)         (50)         (49)                                   
      Meninges, Infiltration Cellular, Mononuclear                                                                                  
          Cell                                         1 (2%)                                                                       
   Spinal Cord                                        (2)                                                                           
      Hemorrhage                                       1 (50%)                                                                      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Larynx                                             (50)         (50)         (50)         (48)                                   
      Metaplasia, Squamous                             1 (2%)                                                                       
   Lung                                               (50)         (50)         (50)         (49)                                   
      Foreign Body                                                               1 (2%)                                             
      Inflammation, Granulomatous                                                             2 (4%)                                
      Mineralization                                                             1 (2%)                                             
      Thrombosis                                       1 (2%)                                 2 (4%)                                
      Alveolar Epithelium, Hyperplasia                 3 (6%)       2 (4%)       4 (8%)       3 (6%)                                
      Alveolus, Infiltration Cellular, Histiocyte      2 (4%)       1 (2%)                    3 (6%)                                
      Artery, Inflammation, Acute                                                             2 (4%)                                
   Nose                                               (50)         (50)         (49)         (49)                                   
      Inflammation, Acute                                           1 (2%)                                                          
      Inflammation, Suppurative                        3 (6%)                    1 (2%)       1 (2%)                                
      Respiratory Epithelium, Metaplasia, Squamous     2 (4%)                                                                       
      Respiratory Epithelium, Necrosis                 2 (4%)                                 1 (2%)                                
   Pleura                                                          (1)          (1)                                                 
      Hyperplasia                                                   1 (100%)                                                        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                (50)         (50)         (50)         (48)                                   
      Cataract                                                                                2 (4%)                                
      Anterior Chamber, Inflammation, Acute            1 (2%)                                 1 (2%)                                
      Cornea, Erosion                                                                         3 (6%)                                
      Cornea, Hyperplasia, Squamous                    1 (2%)       2 (4%)                    2 (4%)                                
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page    6                                                              
                                                                                                                                   
NTP Experiment-Test: 90004-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                PROPYLENE GLYCOL MONO-T-BUTYL ETHER                            Date: 01/02/02    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 08:46:38    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE FEMALE                        CONTROL      75 PPM       300 PPM      1200 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
SPECIAL SENSES SYSTEM - CONT                                                                                                        
      Cornea, Inflammation, Acute                                                             1 (2%)                                
      Cornea, Inflammation, Chronic Active             1 (2%)       2 (4%)                    4 (8%)                                
      Cornea, Mineralization                           1 (2%)       2 (4%)                   20 (42%)                               
      Cornea, Ulcer                                                 1 (2%)                    1 (2%)                                
      Retrobulbar, Inflammation, Granulomatous                                                1 (2%)                                
   Harderian Gland                                    (50)         (50)         (50)         (49)                                   
      Hyperplasia                                      3 (6%)       3 (6%)       4 (8%)       4 (8%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (49)         (50)         (50)         (48)                                   
      Infarct                                          1 (2%)                    2 (4%)       3 (6%)                                
      Metaplasia, Osseous                              2 (4%)       1 (2%)       1 (2%)       1 (2%)                                
      Nephropathy                                     34 (69%)     34 (68%)     32 (64%)     34 (71%)                               
      Thrombosis                                                                 1 (2%)                                             
      Pelvis, Dilatation                                                         1 (2%)                                             
      Renal Tubule, Degeneration, Hyaline              1 (2%)                                 1 (2%)                                
      Renal Tubule, Necrosis                                                     1 (2%)                                             
   Urinary Bladder                                    (50)         (49)         (50)         (47)                                   
      Inflammation, Acute                                                                     1 (2%)                                
      Transitional Epithelium, Hyperplasia             1 (2%)                                                                       
                                                                                                                                    
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page    7                                                              
                                                                                                                                   
NTP Experiment-Test: 90004-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                PROPYLENE GLYCOL MONO-T-BUTYL ETHER                            Date: 01/02/02    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 08:46:38    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE MALE                          CONTROL      75 PPM       300 PPM      1200 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
DISPOSITION SUMMARY                                                                                                                 
                                                                                                                                    
  Animals Initially In Study                          50           50           50           50                                     
  Early Deaths                                                                                                                      
    Natural Death                                     11            4            4            5                                     
    Moribund Sacrifice                                 4            6            6            8                                     
  Survivors                                                                                                                         
    Terminal Sacrifice                                35           40           40           37                                     
                                                                                                                                    
  Animals Examined Microscopically                    50           50           50           50                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Gallbladder                                        (38)         (41)         (39)         (40)                                   
      Degeneration, Hyaline                                         1 (2%)       2 (5%)                                             
   Intestine Large, Colon                             (46)         (48)         (48)         (47)                                   
      Serosa, Inflammation, Granulomatous                           1 (2%)                                                          
   Intestine Large, Rectum                            (46)         (48)         (48)         (46)                                   
      Infiltration Cellular, Mixed Cell                1 (2%)                                                                       
   Intestine Large, Cecum                             (43)         (47)         (48)         (48)                                   
      Necrosis                                         1 (2%)       1 (2%)                                                          
   Intestine Small, Jejunum                           (42)         (47)         (47)         (45)                                   
      Infiltration Cellular, Mixed Cell                2 (5%)                    2 (4%)                                             
      Inflammation, Granulomatous                      1 (2%)       1 (2%)                                                          
      Necrosis                                                                   1 (2%)                                             
      Epithelium, Hyperplasia                          1 (2%)                                                                       
   Intestine Small, Ileum                             (43)         (47)         (46)         (46)                                   
      Infiltration Cellular, Mixed Cell                4 (9%)       2 (4%)       2 (4%)       1 (2%)                                
      Inflammation, Acute                                                        1 (2%)                                             
      Inflammation, Chronic Active                                  1 (2%)       1 (2%)                                             
      Necrosis                                                                   1 (2%)                                             
      Epithelium, Hyperplasia                          1 (2%)       1 (2%)                                                          
   Liver                                              (50)         (49)         (50)         (50)                                   
      Basophilic Focus                                 6 (12%)     11 (22%)     16 (32%)      4 (8%)                                
      Clear Cell Focus                                20 (40%)     18 (37%)     16 (32%)     17 (34%)                               
      Eosinophilic Focus                               9 (18%)     14 (29%)     11 (22%)     29 (58%)                               
      Fatty Change                                                  1 (2%)                    2 (4%)                                
      Hematopoietic Cell Proliferation                 1 (2%)       1 (2%)       1 (2%)                                             
      Infarct                                          2 (4%)       1 (2%)       1 (2%)       3 (6%)                                
      Inflammation, Granulomatous                      9 (18%)     12 (24%)     11 (22%)      3 (6%)                                
      Mixed Cell Focus                                                                        4 (8%)                                
      Tension Lipidosis                                1 (2%)       2 (4%)       4 (8%)       2 (4%)                                
      Centrilobular, Necrosis                          1 (2%)       1 (2%)       1 (2%)                                             
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page    8                                                              
                                                                                                                                   
NTP Experiment-Test: 90004-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                PROPYLENE GLYCOL MONO-T-BUTYL ETHER                            Date: 01/02/02    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 08:46:38    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE MALE                          CONTROL      75 PPM       300 PPM      1200 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Hepatocyte, Multinucleated                      27 (54%)     23 (47%)     24 (48%)     46 (92%)                               
   Mesentery                                          (14)         (16)         (13)         (11)                                   
      Inflammation, Granulomatous                      2 (14%)      1 (6%)       4 (31%)      1 (9%)                                
      Artery, Inflammation                                                       1 (8%)       2 (18%)                               
      Fat, Necrosis                                   10 (71%)     14 (88%)      7 (54%)      7 (64%)                               
   Pancreas                                           (48)         (49)         (50)         (50)                                   
      Atrophy                                                       1 (2%)                                                          
      Basophilic Focus                                                                        1 (2%)                                
   Stomach, Forestomach                               (48)         (49)         (50)         (50)                                   
      Hyperkeratosis                                                             1 (2%)                                             
      Hyperplasia, Squamous                                                                   1 (2%)                                
      Inflammation                                     2 (4%)       3 (6%)       9 (18%)      9 (18%)                               
      Ulcer                                                                                   1 (2%)                                
      Artery, Inflammation, Chronic Active                                       1 (2%)                                             
      Epithelium, Hyperplasia, Squamous                2 (4%)       5 (10%)      9 (18%)      7 (14%)                               
      Epithelium, Ulcer                                1 (2%)       1 (2%)       3 (6%)       3 (6%)                                
   Stomach, Glandular                                 (46)         (48)         (50)         (48)                                   
      Hyperplasia                                      1 (2%)                                                                       
      Metaplasia, Squamous                             1 (2%)                                                                       
      Mineralization                                   1 (2%)       1 (2%)       1 (2%)       1 (2%)                                
      Necrosis                                                      2 (4%)       1 (2%)                                             
   Tooth                                              (50)         (50)         (50)         (50)                                   
      Inflammation, Chronic Active                     3 (6%)       5 (10%)      4 (8%)      15 (30%)                               
      Malformation                                    24 (48%)     15 (30%)     15 (30%)     16 (32%)                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Heart                                              (50)         (50)         (50)         (50)                                   
      Cardiomyopathy                                   9 (18%)      8 (16%)     11 (22%)      7 (14%)                               
      Mineralization                                   1 (2%)       1 (2%)                                                          
      Necrosis                                         2 (4%)                                                                       
      Thrombosis                                                                 1 (2%)       1 (2%)                                
      Artery, Inflammation, Chronic Active                                       3 (6%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (48)         (49)         (50)         (50)                                   
      Hyperplasia                                     11 (23%)      9 (18%)     14 (28%)      7 (14%)                               
      Hypertrophy                                     34 (71%)     32 (65%)     29 (58%)     18 (36%)                               
   Adrenal Medulla                                    (47)         (49)         (49)         (49)                                   
      Hyperplasia                                                   1 (2%)       1 (2%)       2 (4%)                                
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page    9                                                              
                                                                                                                                   
NTP Experiment-Test: 90004-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                PROPYLENE GLYCOL MONO-T-BUTYL ETHER                            Date: 01/02/02    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 08:46:38    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE MALE                          CONTROL      75 PPM       300 PPM      1200 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ENDOCRINE SYSTEM - CONT                                                                                                             
      Infiltration Cellular, Polymorphonuclear                                   1 (2%)                                             
   Islets, Pancreatic                                 (48)         (49)         (50)         (50)                                   
      Hyperplasia                                                   1 (2%)                                                          
   Pituitary Gland                                    (43)         (48)         (50)         (48)                                   
      Cyst                                                          1 (2%)                                                          
      Pars Distalis, Hyperplasia                                    1 (2%)       4 (8%)       1 (2%)                                
   Thyroid Gland                                      (48)         (48)         (49)         (49)                                   
      Follicular Cell, Hyperplasia                                               1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Epididymis                                         (50)         (50)         (50)         (50)                                   
      Granuloma Sperm                                  1 (2%)       1 (2%)                                                          
      Inflammation, Chronic                                         1 (2%)                                                          
   Preputial Gland                                    (50)         (50)         (50)         (50)                                   
      Ectasia                                          2 (4%)       1 (2%)       1 (2%)                                             
      Hyperplasia, Squamous                            1 (2%)                                 2 (4%)                                
      Inflammation, Chronic                                         2 (4%)       2 (4%)                                             
      Inflammation, Suppurative                                     3 (6%)       2 (4%)       2 (4%)                                
   Prostate                                           (49)         (49)         (47)         (50)                                   
      Inflammation, Suppurative                                                  1 (2%)                                             
      Artery, Inflammation, Chronic Active                          1 (2%)       1 (2%)                                             
   Seminal Vesicle                                    (47)         (49)         (49)         (49)                                   
      Inflammation, Chronic                                         2 (4%)       1 (2%)                                             
   Testes                                             (50)         (50)         (50)         (50)                                   
      Amyloid Deposition                                            1 (2%)                                                          
      Atrophy                                                       1 (2%)       1 (2%)                                             
      Mineralization                                   1 (2%)                                                                       
      Germinal Epithelium, Degeneration                1 (2%)                                 1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (49)         (49)         (50)         (50)                                   
      Thrombosis                                                                              1 (2%)                                
   Lymph Node, Bronchial                              (32)         (36)         (36)         (35)                                   
      Infiltration Cellular, Plasma Cell               1 (3%)                                                                       
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page   10                                                              
                                                                                                                                   
NTP Experiment-Test: 90004-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                PROPYLENE GLYCOL MONO-T-BUTYL ETHER                            Date: 01/02/02    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 08:46:38    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE MALE                          CONTROL      75 PPM       300 PPM      1200 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
HEMATOPOIETIC SYSTEM - CONT                                                                                                         
   Lymph Node, Mandibular                             (28)         (38)         (30)         (25)                                   
      Infiltration Cellular, Plasma Cell                                                      1 (4%)                                
   Lymph Node, Mesenteric                             (48)         (49)         (49)         (50)                                   
      Angiectasis                                                                1 (2%)                                             
      Infiltration Cellular, Plasma Cell               2 (4%)       1 (2%)       4 (8%)                                             
      Infiltration Cellular, Mixed Cell                1 (2%)                                                                       
      Pigmentation                                                  1 (2%)                                                          
   Lymph Node, Mediastinal                            (39)         (39)         (43)         (36)                                   
      Inflammation, Granulomatous                                   1 (3%)                                                          
   Spleen                                             (48)         (48)         (50)         (50)                                   
      Angiectasis                                                                             1 (2%)                                
      Hematopoietic Cell Proliferation                 4 (8%)       2 (4%)       2 (4%)       2 (4%)                                
      Hyperplasia, Lymphoid                                                                   1 (2%)                                
      Infiltration Cellular, Histiocyte                1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Skin                                               (49)         (50)         (50)         (50)                                   
      Infiltration Cellular, Mixed Cell                             1 (2%)                                                          
      Inflammation, Chronic Active                     4 (8%)       1 (2%)       6 (12%)      5 (10%)                               
      Epidermis, Hyperplasia                                                                  1 (2%)                                
      Subcutaneous Tissue, Edema                       1 (2%)                                                                       
      Subcutaneous Tissue, Hemorrhage                  1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (50)         (50)         (50)         (50)                                   
      Fibrous Osteodystrophy                           1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (50)         (50)         (50)         (50)                                   
      Necrosis                                         1 (2%)                                                                       
      Artery, Inflammation, Chronic Active                                       1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Larynx                                             (49)         (50)         (50)         (50)                                   
      Artery, Inflammation, Chronic Active                                       1 (2%)                                             
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page   11                                                              
                                                                                                                                   
NTP Experiment-Test: 90004-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                PROPYLENE GLYCOL MONO-T-BUTYL ETHER                            Date: 01/02/02    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 08:46:38    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE MALE                          CONTROL      75 PPM       300 PPM      1200 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
RESPIRATORY SYSTEM - CONT                                                                                                           
   Lung                                               (50)         (50)         (50)         (50)                                   
      Hemorrhage                                                    1 (2%)                    1 (2%)                                
      Inflammation, Granulomatous                                   1 (2%)                    1 (2%)                                
      Inflammation, Suppurative                                                  1 (2%)                                             
      Mineralization                                                1 (2%)                                                          
      Thrombosis                                                    3 (6%)                                                          
      Alveolar Epithelium, Hyperplasia                 6 (12%)      4 (8%)       4 (8%)                                             
      Alveolus, Infiltration Cellular, Histiocyte      1 (2%)                                 2 (4%)                                
   Nose                                               (50)         (49)         (50)         (50)                                   
      Amyloid Deposition                                            1 (2%)                                                          
      Inflammation, Suppurative                        5 (10%)                   4 (8%)       6 (12%)                               
      Olfactory Epithelium, Atrophy                                              1 (2%)                                             
      Respiratory Epithelium, Metaplasia, Squamous                                            1 (2%)                                
      Respiratory Epithelium, Necrosis                                           1 (2%)       1 (2%)                                
   Pleura                                             (1)                       (1)                                                 
      Necrosis, Fatty                                                            1 (100%)                                           
   Trachea                                            (48)         (48)         (50)         (50)                                   
      Degeneration, Hyaline                                                      1 (2%)                                             
      Inflammation, Suppurative                                                  1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                (48)         (49)         (50)         (50)                                   
      Cornea, Erosion                                                                         1 (2%)                                
      Cornea, Hyperplasia, Squamous                    1 (2%)                                 1 (2%)                                
      Cornea, Inflammation, Chronic Active             1 (2%)                    1 (2%)       1 (2%)                                
      Cornea, Mineralization                                                                  3 (6%)                                
   Harderian Gland                                    (50)         (50)         (50)         (50)                                   
      Hyperplasia                                     10 (20%)      3 (6%)       5 (10%)      1 (2%)                                
   Zymbal's Gland                                     (35)         (35)         (36)         (32)                                   
      Hyperplasia                                      1 (3%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (50)         (49)         (50)         (50)                                   
      Amyloid Deposition                                            1 (2%)                                                          
      Cyst                                             1 (2%)       1 (2%)       2 (4%)                                             
      Infarct                                          3 (6%)       3 (6%)       3 (6%)       7 (14%)                               
      Inflammation, Chronic, Suppurative                            1 (2%)                    1 (2%)                                
      Metaplasia, Osseous                              3 (6%)       6 (12%)      2 (4%)                                             
      Mineralization                                                1 (2%)                                                          
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page   12                                                              
                                                                                                                                   
NTP Experiment-Test: 90004-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                PROPYLENE GLYCOL MONO-T-BUTYL ETHER                            Date: 01/02/02    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 08:46:38    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE MALE                          CONTROL      75 PPM       300 PPM      1200 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
URINARY SYSTEM - CONT                                                                                                               
      Nephropathy                                     41 (82%)     40 (82%)     44 (88%)     36 (72%)                               
      Artery, Inflammation, Chronic Active                                       2 (4%)       1 (2%)                                
      Papilla, Inflammation, Suppurative                                         1 (2%)                                             
      Pelvis, Dilatation                                                         1 (2%)       2 (4%)                                
      Renal Tubule, Hyperplasia                        2 (4%)                    1 (2%)                                             
      Renal Tubule, Necrosis                           1 (2%)                                                                       
      Transitional Epithelium, Hyperplasia                                                    2 (4%)                                
   Urinary Bladder                                    (48)         (48)         (49)         (50)                                   
      Inflammation, Chronic Active                                               1 (2%)                                             
      Artery, Inflammation, Chronic Active                          1 (2%)       1 (2%)                                             
                                                                                                                                    
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page   13                                                              
                                                                                                                                   
                             ------------------------------------------------------------                                           
                             ----------              END OF REPORT             ----------                                           
                             ------------------------------------------------------------