National Toxicology Program

National Toxicology Program
https://ntp.niehs.nih.gov/go/12623

TDMS Study 90004-07 Pathology Tables

NTP Experiment-Test: 90004-07         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                PROPYLENE GLYCOL MONO-T-BUTYL ETHER                            Date: 03/04/03
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:24:54

                                                          FINAL#2/RATS




       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: 90004-07         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                PROPYLENE GLYCOL MONO-T-BUTYL ETHER                            Date: 03/04/03    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:24:54    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS FEMALE                   CONTROL      75 PPM       300 PPM      1200 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
DISPOSITION SUMMARY                                                                                                                 
                                                                                                                                    
  Animals Initially In Study                          50           50           50           50                                     
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                14           12           20           11                                     
    Natural Death                                      3            4            2            3                                     
  Survivors                                                                                                                         
    Terminal Sacrifice                                33           34           28           36                                     
                                                                                                                                    
  Animals Examined Microscopically                    50           50           50           50                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Liver                                              (49)         (50)         (50)         (50)                                   
      Angiectasis                                      1 (2%)                    3 (6%)       1 (2%)                                
      Basophilic Focus                                39 (80%)     45 (90%)     43 (86%)     40 (80%)                               
      Clear Cell Focus                                12 (24%)     13 (26%)     11 (22%)     27 (54%)                               
      Eosinophilic Focus                               1 (2%)                                 1 (2%)                                
      Fatty Change                                                  1 (2%)                                                          
      Hepatodiaphragmatic Nodule                       8 (16%)     10 (20%)      9 (18%)      7 (14%)                               
      Infarct                                          1 (2%)                                                                       
      Inflammation, Granulomatous                      1 (2%)                    1 (2%)       2 (4%)                                
      Necrosis                                                      1 (2%)       1 (2%)       2 (4%)                                
      Thrombosis                                                                              1 (2%)                                
      Vacuolization Cytoplasmic                        3 (6%)       4 (8%)       3 (6%)                                             
      Bile Duct, Dilatation                            1 (2%)                                                                       
      Serosa, Hemorrhage                               1 (2%)                                                                       
   Mesentery                                          (17)         (23)         (10)         (17)                                   
      Necrosis                                        17 (100%)    21 (91%)      9 (90%)     17 (100%)                              
      Fat, Hemorrhage                                  1 (6%)       1 (4%)                                                          
   Pancreas                                           (49)         (50)         (50)         (50)                                   
      Cyst                                                                       1 (2%)                                             
      Necrosis                                                      1 (2%)                                                          
   Stomach, Forestomach                               (49)         (50)         (50)         (49)                                   
      Erosion                                                                                 1 (2%)                                
      Inflammation, Suppurative                                                  1 (2%)                                             
      Ulcer                                                                      4 (8%)                                             
   Stomach, Glandular                                 (49)         (50)         (50)         (49)                                   
      Ulcer                                            1 (2%)                                                                       
      Epithelium, Hyperplasia                                                                 1 (2%)                                
   Tongue                                             (2)                                    (1)                                    
      Epithelium, Hyperkeratosis                                                              1 (100%)                              
      Epithelium, Hyperplasia                          1 (50%)                                                                      
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page    2                                                              
                                                                                                                                   
NTP Experiment-Test: 90004-07         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                PROPYLENE GLYCOL MONO-T-BUTYL ETHER                            Date: 03/04/03    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:24:54    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS FEMALE                   CONTROL      75 PPM       300 PPM      1200 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
   Tooth                                              (1)                                                                           
      Peridontal Tissue, Inflammation                  1 (100%)                                                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Heart                                              (50)         (50)         (50)         (50)                                   
      Cardiomyopathy                                                3 (6%)       1 (2%)                                             
      Atrium, Thrombosis                                            2 (4%)                                                          
      Epicardium, Inflammation, Chronic                                          1 (2%)                                             
      Myocardium, Degeneration                                                   1 (2%)                                             
      Myocardium, Necrosis                                                       1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (49)         (50)         (50)         (50)                                   
      Accessory Adrenal Cortical Nodule                                                       1 (2%)                                
      Atrophy                                                       1 (2%)                                                          
      Degeneration, Cystic                             1 (2%)                                                                       
      Hemorrhage                                                                 1 (2%)                                             
      Hyperplasia                                      2 (4%)                    2 (4%)       1 (2%)                                
      Metaplasia, Osseous                              1 (2%)                                                                       
      Vacuolization Cytoplasmic                       15 (31%)     10 (20%)      6 (12%)      5 (10%)                               
   Adrenal Medulla                                    (49)         (50)         (50)         (50)                                   
      Hyperplasia                                      1 (2%)       1 (2%)       2 (4%)                                             
   Pituitary Gland                                    (49)         (50)         (50)         (49)                                   
      Angiectasis                                      4 (8%)       4 (8%)       1 (2%)       4 (8%)                                
      Cyst                                                                                    1 (2%)                                
      Hemorrhage                                       1 (2%)                    1 (2%)                                             
      Hyperplasia                                      3 (6%)       6 (12%)      3 (6%)       3 (6%)                                
      Pars Intermedia, Vacuolization Cytoplasmic                                              1 (2%)                                
   Thyroid Gland                                      (49)         (50)         (50)         (50)                                   
      C-Cell, Hyperplasia                              9 (18%)      8 (16%)      7 (14%)      5 (10%)                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page    3                                                              
                                                                                                                                   
NTP Experiment-Test: 90004-07         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                PROPYLENE GLYCOL MONO-T-BUTYL ETHER                            Date: 03/04/03    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:24:54    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS FEMALE                   CONTROL      75 PPM       300 PPM      1200 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
GENITAL SYSTEM - CONT                                                                                                               
   Clitoral Gland                                     (50)         (50)         (50)         (50)                                   
      Cyst                                             2 (4%)       3 (6%)       1 (2%)       4 (8%)                                
      Hyperplasia                                      3 (6%)       3 (6%)       2 (4%)       2 (4%)                                
      Inflammation, Chronic                                         1 (2%)       2 (4%)       1 (2%)                                
   Ovary                                              (50)         (50)         (50)         (50)                                   
      Cyst                                             6 (12%)      5 (10%)      3 (6%)       8 (16%)                               
      Hemorrhage                                                                 1 (2%)                                             
   Uterus                                             (50)         (50)         (50)         (50)                                   
      Decidual Reaction                                1 (2%)                                                                       
      Hemorrhage                                       1 (2%)                                 1 (2%)                                
      Hemorrhage, Chronic                              1 (2%)                                                                       
      Necrosis                                                                   1 (2%)                                             
      Endometrium, Hyperplasia                                                   1 (2%)       2 (4%)                                
      Endometrium, Ulcer                                                                      1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Lymph Node                                         (5)          (3)          (3)          (6)                                    
      Deep Cervical, Infiltration Cellular,                                                                                         
        Histiocyte                                                               1 (33%)                                            
      Deep Cervical, Inflammation, Chronic             1 (20%)                                                                      
   Lymph Node, Bronchial                              (9)          (4)          (10)         (5)                                    
      Angiectasis                                      1 (11%)                                1 (20%)                               
      Infiltration Cellular, Histiocyte                                          1 (10%)                                            
   Lymph Node, Mandibular                             (1)          (2)          (2)                                                 
      Ectasia                                                       1 (50%)      1 (50%)                                            
   Lymph Node, Mesenteric                             (50)         (50)         (50)         (50)                                   
      Fibrosis                                                      1 (2%)                                                          
      Hemorrhage                                                    1 (2%)                                                          
   Lymph Node, Mediastinal                            (43)         (46)         (45)         (43)                                   
      Angiectasis                                      3 (7%)       1 (2%)       1 (2%)       2 (5%)                                
      Fibrosis                                                      1 (2%)       1 (2%)                                             
      Hemorrhage                                                    1 (2%)                                                          
      Infiltration Cellular, Histiocyte                1 (2%)       2 (4%)       4 (9%)                                             
      Inflammation, Suppurative                                                  1 (2%)                                             
      Pigmentation                                     3 (7%)       1 (2%)                                                          
   Spleen                                             (49)         (50)         (50)         (50)                                   
      Accessory Spleen                                 1 (2%)       2 (4%)                                                          
      Degeneration                                                  1 (2%)                                                          
      Fibrosis                                                                                2 (4%)                                
      Hematopoietic Cell Proliferation                                                        1 (2%)                                
      Hemorrhage                                       1 (2%)                                                                       
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page    4                                                              
                                                                                                                                   
NTP Experiment-Test: 90004-07         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                PROPYLENE GLYCOL MONO-T-BUTYL ETHER                            Date: 03/04/03    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:24:54    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS FEMALE                   CONTROL      75 PPM       300 PPM      1200 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
HEMATOPOIETIC SYSTEM - CONT                                                                                                         
      Necrosis                                                      1 (2%)                    3 (6%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (49)         (50)         (50)         (50)                                   
      Galactocele                                                   7 (14%)      2 (4%)       1 (2%)                                
   Skin                                               (50)         (50)         (50)         (50)                                   
      Cyst Epithelial Inclusion                                     1 (2%)       1 (2%)                                             
      Hyperkeratosis                                                             1 (2%)                                             
      Inflammation, Chronic                                         1 (2%)       1 (2%)       1 (2%)                                
      Ulcer                                            1 (2%)                                 1 (2%)                                
      Subcutaneous Tissue, Hemorrhage                                                         1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (50)         (50)         (50)         (50)                                   
      Fibrous Osteodystrophy                                        1 (2%)                                                          
      Maxilla, Necrosis                                1 (2%)                                                                       
      Metatarsal, Fracture                                                                    1 (2%)                                
      Tibia, Osteopetrosis                                          1 (2%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (49)         (50)         (50)         (50)                                   
      Compression                                      5 (10%)      9 (18%)      8 (16%)      4 (8%)                                
      Hemorrhage                                       4 (8%)       3 (6%)       6 (12%)      2 (4%)                                
      Hydrocephalus                                                 1 (2%)                                                          
      Medulla, Gliosis, Focal                                                    1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Larynx                                             (49)         (50)         (50)         (50)                                   
      Foreign Body                                     1 (2%)       1 (2%)                                                          
      Inflammation, Suppurative                        4 (8%)       2 (4%)       1 (2%)       2 (4%)                                
      Epiglottis, Metaplasia, Squamous                                           1 (2%)       2 (4%)                                
      Respiratory Epithelium, Epiglottis,                                                                                           
        Degeneration                                                             1 (2%)                                             
   Lung                                               (50)         (50)         (50)         (50)                                   
      Foreign Body                                                                            1 (2%)                                
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page    5                                                              
                                                                                                                                   
NTP Experiment-Test: 90004-07         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                PROPYLENE GLYCOL MONO-T-BUTYL ETHER                            Date: 03/04/03    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:24:54    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS FEMALE                   CONTROL      75 PPM       300 PPM      1200 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
RESPIRATORY SYSTEM - CONT                                                                                                           
      Hemorrhage                                       1 (2%)       2 (4%)                    1 (2%)                                
      Inflammation, Chronic                            9 (18%)      2 (4%)       7 (14%)      6 (12%)                               
      Metaplasia, Osseous                                                        1 (2%)                                             
      Thrombosis                                       1 (2%)                                                                       
      Alveolar Epithelium, Hyperplasia                 6 (12%)      4 (8%)       5 (10%)      4 (8%)                                
      Alveolus, Infiltration Cellular, Histiocyte     15 (30%)      9 (18%)     13 (26%)     20 (40%)                               
      Alveolus, Proteinosis                            4 (8%)                    3 (6%)       2 (4%)                                
      Bronchiole, Hyperplasia                          1 (2%)       1 (2%)                                                          
      Interstitium, Fibrosis                           4 (8%)       1 (2%)       4 (8%)       2 (4%)                                
      Mediastinum, Inflammation, Granulomatous                                   1 (2%)                                             
   Nose                                               (49)         (49)         (50)         (50)                                   
      Foreign Body                                     2 (4%)       2 (4%)       2 (4%)                                             
      Inflammation, Suppurative                        4 (8%)       2 (4%)       5 (10%)                                            
      Glands, Dilatation                                                                      4 (8%)                                
      Goblet Cell, Hyperplasia                                                                3 (6%)                                
      Nasolacrimal Duct, Inflammation, Suppurative     1 (2%)       1 (2%)       4 (8%)       1 (2%)                                
      Olfactory Epithelium, Degeneration, Hyaline     10 (20%)     22 (45%)     48 (96%)     50 (100%)                              
      Respiratory Epithelium, Hyperplasia              2 (4%)       1 (2%)       1 (2%)       1 (2%)                                
   Pleura                                             (50)         (50)         (49)         (50)                                   
      Inflammation, Chronic                           15 (30%)     10 (20%)     11 (22%)     17 (34%)                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                (49)         (50)         (50)         (50)                                   
      Atrophy                                                                    2 (4%)                                             
      Phthisis Bulbi                                   1 (2%)                    1 (2%)                                             
      Anterior Chamber, Sclera, Inflammation,                                                                                       
        Suppurative                                                              1 (2%)                                             
      Cornea, Edema                                                                           1 (2%)                                
      Cornea, Inflammation, Chronic                                              1 (2%)       1 (2%)                                
      Cornea, Mineralization                                                                 10 (20%)                               
      Cornea, Necrosis                                                                        1 (2%)                                
      Lens, Cataract                                   1 (2%)       4 (8%)       3 (6%)       1 (2%)                                
      Lens, Mineralization                                          1 (2%)                                                          
      Sclera, Inflammation, Suppurative                1 (2%)                                                                       
   Zymbal's Gland                                     (42)         (44)         (43)         (46)                                   
      Cyst                                                                       1 (2%)                                             
      Hyperplasia                                                                1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page    6                                                              
                                                                                                                                   
NTP Experiment-Test: 90004-07         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                PROPYLENE GLYCOL MONO-T-BUTYL ETHER                            Date: 03/04/03    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:24:54    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS FEMALE                   CONTROL      75 PPM       300 PPM      1200 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
URINARY SYSTEM - CONT                                                                                                               
   Kidney                                             (49)         (50)         (50)         (50)                                   
      Inflammation, Suppurative                                     2 (4%)                                                          
      Nephropathy, Chronic                            45 (92%)     45 (90%)     45 (90%)     49 (98%)                               
      Cortex, Infarct                                                                         1 (2%)                                
      Cortex, Renal Tubule, Accumulation, Hyaline                                                                                   
        Droplet                                        1 (2%)       2 (4%)                    1 (2%)                                
      Cortex, Renal Tubule, Hyperplasia                                          1 (2%)       1 (2%)                                
      Pelvis, Mineralization                          13 (27%)      5 (10%)      7 (14%)      3 (6%)                                
      Pelvis, Transitional Epithelium, Hyperplasia                  4 (8%)                                                          
      Renal Tubule, Mineralization                                               2 (4%)                                             
   Urethra                                                                                   (1)                                    
      Transitional Epithelium, Hyperplasia                                                    1 (100%)                              
   Urinary Bladder                                    (49)         (50)         (50)         (50)                                   
      Hemorrhage                                       1 (2%)                                                                       
      Mineralization                                                             1 (2%)                                             
      Ulcer                                                                      1 (2%)                                             
      Transitional Epithelium, Hyperplasia             1 (2%)       1 (2%)                                                          
      Transitional Epithelium, Mineralization                                    1 (2%)                                             
                                                                                                                                    
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page    7                                                              
                                                                                                                                   
NTP Experiment-Test: 90004-07         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                PROPYLENE GLYCOL MONO-T-BUTYL ETHER                            Date: 03/04/03    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:24:54    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS MALE                     CONTROL      75 PPM       300 PPM      1200 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
DISPOSITION SUMMARY                                                                                                                 
                                                                                                                                    
  Animals Initially In Study                          50           50           50           50                                     
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                20           15           26           22                                     
    Natural Death                                      3            6            8            6                                     
  Survivors                                                                                                                         
    Terminal Sacrifice                                27           29           16           22                                     
                                                                                                                                    
  Animals Examined Microscopically                    50           50           50           50                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Intestine Large, Rectum                            (50)         (48)         (47)         (48)                                   
      Diverticulum                                     1 (2%)                                                                       
   Intestine Large, Cecum                             (47)         (47)         (47)         (45)                                   
      Hemorrhage                                                                 1 (2%)                                             
      Necrosis                                                      1 (2%)                                                          
   Intestine Small, Duodenum                          (48)         (47)         (47)         (47)                                   
      Epithelium, Hyperplasia                                                                 1 (2%)                                
   Intestine Small, Jejunum                           (47)         (47)         (42)         (46)                                   
      Epithelium, Hyperplasia                                                                 1 (2%)                                
   Intestine Small, Ileum                             (47)         (47)         (43)         (45)                                   
      Epithelium, Hyperplasia                                                                 1 (2%)                                
   Liver                                              (50)         (50)         (49)         (50)                                   
      Basophilic Focus                                 6 (12%)     18 (36%)     15 (31%)     17 (34%)                               
      Clear Cell Focus                                 8 (16%)     11 (22%)     11 (22%)      9 (18%)                               
      Degeneration, Cystic                             1 (2%)                    1 (2%)       3 (6%)                                
      Eosinophilic Focus                                            1 (2%)       1 (2%)       2 (4%)                                
      Fatty Change                                     3 (6%)                                 1 (2%)                                
      Hepatodiaphragmatic Nodule                       1 (2%)       6 (12%)     11 (22%)      5 (10%)                               
      Necrosis                                                                   3 (6%)       1 (2%)                                
      Thrombosis                                       1 (2%)                                                                       
      Vacuolization Cytoplasmic                        3 (6%)       1 (2%)       2 (4%)       1 (2%)                                
      Bile Duct, Cyst                                  1 (2%)                                                                       
      Bile Duct, Dilatation                                                      1 (2%)                                             
      Bile Duct, Hyperplasia                                                     1 (2%)       1 (2%)                                
      Hepatocyte, Regeneration                                                   1 (2%)                                             
   Mesentery                                          (13)         (9)          (10)         (7)                                    
      Necrosis                                        13 (100%)     9 (100%)    10 (100%)     5 (71%)                               
      Thrombosis                                                                              1 (14%)                               
      Fat, Hemorrhage                                               1 (11%)                                                         
   Oral Mucosa                                                     (1)                                                              
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page    8                                                              
                                                                                                                                   
NTP Experiment-Test: 90004-07         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                PROPYLENE GLYCOL MONO-T-BUTYL ETHER                            Date: 03/04/03    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:24:54    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS MALE                     CONTROL      75 PPM       300 PPM      1200 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Ulcer                                                         1 (100%)                                                        
   Pancreas                                           (50)         (50)         (49)         (50)                                   
      Acinus, Atrophy                                               1 (2%)       1 (2%)                                             
      Artery, Inflammation                                                                    1 (2%)                                
   Stomach, Forestomach                               (50)         (50)         (49)         (50)                                   
      Hyperplasia, Squamous                            2 (4%)       1 (2%)       2 (4%)       4 (8%)                                
      Inflammation, Suppurative                        1 (2%)                                                                       
      Necrosis                                                                   1 (2%)                                             
      Ulcer                                            3 (6%)                    3 (6%)       4 (8%)                                
   Stomach, Glandular                                 (50)         (50)         (49)         (50)                                   
      Erosion                                                                    3 (6%)                                             
      Mineralization                                                             1 (2%)                                             
      Necrosis                                         1 (2%)                                 1 (2%)                                
      Ulcer                                                                      1 (2%)                                             
      Epithelium, Hyperplasia                                                                 1 (2%)                                
   Tongue                                             (2)                       (3)          (1)                                    
      Epithelium, Hyperplasia                          2 (100%)                  3 (100%)     1 (100%)                              
   Tooth                                              (1)          (2)                       (1)                                    
      Malformation                                                  1 (50%)                                                         
      Peridontal Tissue, Inflammation                  1 (100%)     1 (50%)                   1 (100%)                              
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Blood Vessel                                       (50)         (50)         (49)         (50)                                   
      Pulmonary Artery, Degeneration, Mucoid                                     1 (2%)                                             
   Heart                                              (50)         (50)         (49)         (50)                                   
      Cardiomyopathy                                   7 (14%)      6 (12%)      4 (8%)       7 (14%)                               
      Inflammation, Focal, Suppurative                                           1 (2%)                                             
      Atrium, Thrombosis                               1 (2%)                    1 (2%)                                             
      Myocardium, Fibrosis                                          1 (2%)                                                          
      Myocardium, Necrosis                             1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (50)         (50)         (49)         (50)                                   
      Hyperplasia                                                   1 (2%)                    3 (6%)                                
      Mineralization                                                             1 (2%)                                             
      Necrosis                                         1 (2%)                                                                       
      Vacuolization Cytoplasmic                        6 (12%)     14 (28%)      6 (12%)      9 (18%)                               
   Adrenal Medulla                                    (50)         (50)         (49)         (50)                                   
      Hyperplasia                                      6 (12%)      4 (8%)      11 (22%)      9 (18%)                               
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page    9                                                              
                                                                                                                                   
NTP Experiment-Test: 90004-07         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                PROPYLENE GLYCOL MONO-T-BUTYL ETHER                            Date: 03/04/03    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:24:54    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS MALE                     CONTROL      75 PPM       300 PPM      1200 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ENDOCRINE SYSTEM - CONT                                                                                                             
      Thrombosis                                                                 1 (2%)                                             
   Islets, Pancreatic                                 (50)         (50)         (49)         (50)                                   
      Hyperplasia                                                                1 (2%)       1 (2%)                                
   Parathyroid Gland                                  (49)         (49)         (48)         (49)                                   
      Hyperplasia                                      1 (2%)                                                                       
   Pituitary Gland                                    (50)         (50)         (49)         (50)                                   
      Angiectasis                                      1 (2%)       3 (6%)       1 (2%)                                             
      Atrophy                                                                                 1 (2%)                                
      Cyst                                                          1 (2%)                                                          
      Hemorrhage                                       1 (2%)       1 (2%)       2 (4%)                                             
      Hyperplasia                                      5 (10%)      2 (4%)       4 (8%)       2 (4%)                                
   Thyroid Gland                                      (50)         (50)         (49)         (50)                                   
      C-Cell, Hyperplasia                              8 (16%)      4 (8%)       7 (14%)      7 (14%)                               
      Follicular Cell, Hyperplasia                     1 (2%)       1 (2%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Penis                                                                        (1)                                                 
      Necrosis                                                                   1 (100%)                                           
   Preputial Gland                                    (50)         (50)         (49)         (50)                                   
      Hyperplasia                                      2 (4%)       3 (6%)       3 (6%)                                             
      Inflammation, Suppurative                        4 (8%)                    4 (8%)                                             
   Prostate                                           (50)         (50)         (49)         (50)                                   
      Hyperplasia                                      1 (2%)       1 (2%)                    1 (2%)                                
      Inflammation, Suppurative                       31 (62%)     24 (48%)     27 (55%)     27 (54%)                               
   Seminal Vesicle                                    (50)         (50)         (49)         (50)                                   
      Dilatation                                                    1 (2%)                                                          
      Inflammation, Suppurative                        1 (2%)                                                                       
      Epithelium, Hyperplasia                          1 (2%)                                                                       
   Testes                                             (50)         (50)         (49)         (50)                                   
      Bilateral, Interstitial Cell, Hyperplasia                                  1 (2%)       1 (2%)                                
      Germinal Epithelium, Atrophy                    20 (40%)     19 (38%)     18 (37%)     20 (40%)                               
      Interstitial Cell, Hyperplasia                   4 (8%)       3 (6%)       7 (14%)      7 (14%)                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page   10                                                              
                                                                                                                                   
NTP Experiment-Test: 90004-07         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                PROPYLENE GLYCOL MONO-T-BUTYL ETHER                            Date: 03/04/03    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:24:54    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS MALE                     CONTROL      75 PPM       300 PPM      1200 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
HEMATOPOIETIC SYSTEM - CONT                                                                                                         
   Lymph Node                                         (12)         (7)          (15)         (6)                                    
      Deep Cervical, Ectasia                                        1 (14%)                                                         
      Deep Cervical, Hyperplasia, Lymphoid             1 (8%)                                                                       
      Deep Cervical, Inflammation                                   1 (14%)                                                         
      Deep Cervical, Inflammation, Suppurative                                                1 (17%)                               
      Pancreatic, Ectasia                              1 (8%)                                                                       
      Pancreatic, Hemorrhage                                                     1 (7%)                                             
      Pancreatic, Pigmentation                                      1 (14%)                                                         
   Lymph Node, Bronchial                              (24)         (7)          (9)          (21)                                   
      Hemorrhage                                                                 1 (11%)                                            
      Hyperplasia, Lymphoid                                                                   2 (10%)                               
   Lymph Node, Mesenteric                             (50)         (50)         (49)         (50)                                   
      Ectasia                                                       1 (2%)                                                          
      Fibrosis                                                                                1 (2%)                                
   Lymph Node, Mediastinal                            (38)         (41)         (46)         (45)                                   
      Angiectasis                                                   1 (2%)       1 (2%)                                             
      Hyperplasia, Lymphoid                            1 (3%)       1 (2%)                                                          
   Spleen                                             (50)         (50)         (49)         (50)                                   
      Accessory Spleen                                 2 (4%)       3 (6%)       4 (8%)       1 (2%)                                
      Fibrosis                                         5 (10%)      1 (2%)       7 (14%)      4 (8%)                                
      Hemorrhage                                       1 (2%)                    1 (2%)       3 (6%)                                
      Necrosis                                         1 (2%)       2 (4%)       5 (10%)      1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (50)         (50)         (49)         (50)                                   
      Galactocele                                      3 (6%)       2 (4%)       2 (4%)       1 (2%)                                
      Metaplasia, Squamous                                          1 (2%)                                                          
      Epithelium, Cyst, Squamous                                                              1 (2%)                                
   Skin                                               (50)         (50)         (49)         (50)                                   
      Cyst Epithelial Inclusion                        3 (6%)       5 (10%)      3 (6%)       1 (2%)                                
      Hyperkeratosis                                   3 (6%)       1 (2%)       6 (12%)      1 (2%)                                
      Inflammation, Granulomatous                                                             2 (4%)                                
      Ulcer                                            1 (2%)                                 2 (4%)                                
      Prepuce, Ulcer                                                             1 (2%)                                             
      Sebaceous Gland, Hyperplasia, Squamous           1 (2%)                                                                       
      Subcutaneous Tissue, Hemorrhage                                                         1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (50)         (50)         (49)         (50)                                   
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page   11                                                              
                                                                                                                                   
NTP Experiment-Test: 90004-07         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                PROPYLENE GLYCOL MONO-T-BUTYL ETHER                            Date: 03/04/03    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:24:54    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS MALE                     CONTROL      75 PPM       300 PPM      1200 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
MUSCULOSKELETAL SYSTEM - CONT                                                                                                       
      Fibrous Osteodystrophy                           1 (2%)                                                                       
      Cranium, Hemorrhage                                                                     1 (2%)                                
   Skeletal Muscle                                                              (2)          (3)                                    
      Mineralization                                                                          1 (33%)                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (50)         (50)         (49)         (50)                                   
      Compression                                      7 (14%)      4 (8%)       5 (10%)      3 (6%)                                
      Gliosis                                                                    1 (2%)                                             
      Hemorrhage                                       4 (8%)       4 (8%)       4 (8%)       2 (4%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Larynx                                             (50)         (49)         (48)         (50)                                   
      Foreign Body                                     1 (2%)       2 (4%)       1 (2%)       1 (2%)                                
      Inflammation, Chronic                            1 (2%)                                 3 (6%)                                
      Inflammation, Suppurative                                     2 (4%)       1 (2%)                                             
      Epiglottis, Hyperplasia                                       1 (2%)       1 (2%)       1 (2%)                                
      Epiglottis, Metaplasia, Squamous                                           1 (2%)                                             
   Lung                                               (50)         (50)         (49)         (50)                                   
      Hemorrhage                                       1 (2%)       2 (4%)       1 (2%)       1 (2%)                                
      Inflammation, Chronic                            5 (10%)      2 (4%)       5 (10%)      4 (8%)                                
      Inflammation, Suppurative                                                  1 (2%)       2 (4%)                                
      Necrosis, Focal                                  1 (2%)                                                                       
      Alveolar Epithelium, Hyperplasia                 6 (12%)      2 (4%)       5 (10%)      6 (12%)                               
      Alveolar Epithelium, Metaplasia, Squamous        1 (2%)                                 4 (8%)                                
      Alveolus, Foreign Body                                                                  2 (4%)                                
      Alveolus, Infiltration Cellular, Histiocyte     11 (22%)      3 (6%)       8 (16%)      8 (16%)                               
      Alveolus, Proteinosis                                         1 (2%)                                                          
      Artery, Mineralization                                                     1 (2%)                                             
      Artery, Thrombosis                                                         1 (2%)                                             
      Interstitium, Fibrosis                           5 (10%)      1 (2%)       4 (8%)       6 (12%)                               
   Nose                                               (50)         (49)         (49)         (50)                                   
      Foreign Body                                     6 (12%)      6 (12%)      4 (8%)       3 (6%)                                
      Hemorrhage                                                                              1 (2%)                                
      Inflammation, Chronic                                                                   4 (8%)                                
      Inflammation, Suppurative                        6 (12%)     10 (20%)     11 (22%)      4 (8%)                                
      Glands, Dilatation                               1 (2%)       2 (4%)       7 (14%)     15 (30%)                               
      Goblet Cell, Hyperplasia                         1 (2%)       1 (2%)       2 (4%)      15 (30%)                               
      Nasolacrimal Duct, Inflammation, Suppurative                  1 (2%)                    1 (2%)                                
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page   12                                                              
                                                                                                                                   
NTP Experiment-Test: 90004-07         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                PROPYLENE GLYCOL MONO-T-BUTYL ETHER                            Date: 03/04/03    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:24:54    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS MALE                     CONTROL      75 PPM       300 PPM      1200 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
RESPIRATORY SYSTEM - CONT                                                                                                           
      Olfactory Epithelium, Degeneration, Hyaline                  25 (51%)     45 (92%)     50 (100%)                              
      Olfactory Epithelium, Hyperplasia, Basal Cell                                           1 (2%)                                
      Respiratory Epithelium, Hyperplasia              2 (4%)       2 (4%)       4 (8%)       3 (6%)                                
      Respiratory Epithelium, Metaplasia, Squamous                               1 (2%)                                             
   Pleura                                             (49)         (50)         (49)         (50)                                   
      Inflammation, Chronic                            6 (12%)      2 (4%)       3 (6%)       7 (14%)                               
      Mesothelium, Hyperplasia                                                                2 (4%)                                
   Trachea                                            (50)         (49)         (49)         (50)                                   
      Glands, Cyst                                                               1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Ear                                                             (1)                       (1)                                    
      Cyst                                                          1 (100%)                                                        
   Eye                                                (50)         (49)         (49)         (50)                                   
      Atrophy                                                                                 1 (2%)                                
      Hemorrhage                                       1 (2%)                                                                       
      Anterior Chamber, Inflammation, Suppurative                                1 (2%)                                             
      Anterior Chamber, Cornea, Inflammation                                                  1 (2%)                                
      Anterior Chamber, Cornea, Inflammation,                                                                                       
        Suppurative                                                                           1 (2%)                                
      Cornea, Inflammation, Suppurative                                          1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (50)         (50)         (49)         (50)                                   
      Infarct                                                       1 (2%)                                                          
      Nephropathy, Chronic                            46 (92%)     50 (100%)    49 (100%)    50 (100%)                              
      Pigmentation                                                               1 (2%)                                             
      Cortex, Infarct                                  4 (8%)                                 2 (4%)                                
      Cortex, Renal Tubule, Accumulation, Hyaline                                                                                   
        Droplet                                        1 (2%)       2 (4%)       9 (18%)     17 (34%)                               
      Cortex, Renal Tubule, Hyperplasia                             3 (6%)       7 (14%)     19 (38%)                               
      Cortex, Renal Tubule, Necrosis                                             1 (2%)                                             
      Papilla, Mineralization                                       8 (16%)     28 (57%)     41 (82%)                               
      Pelvis, Dilatation                               1 (2%)                                                                       
      Pelvis, Inflammation, Suppurative                                          1 (2%)                                             
      Pelvis, Transitional Epithelium, Hyperplasia     2 (4%)       1 (2%)       6 (12%)     15 (30%)                               
      Renal Tubule, Mineralization                     1 (2%)                                                                       
      Renal Tubule, Pigmentation                       1 (2%)                    2 (4%)                                             
   Urethra                                            (1)                       (1)          (2)                                    
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page   13                                                              
                                                                                                                                   
NTP Experiment-Test: 90004-07         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                PROPYLENE GLYCOL MONO-T-BUTYL ETHER                            Date: 03/04/03    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 10:24:54    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS MALE                     CONTROL      75 PPM       300 PPM      1200 PPM                                  
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
URINARY SYSTEM - CONT                                                                                                               
      Inflammation, Suppurative                                                               1 (50%)                               
      Transitional Epithelium, Hyperplasia             1 (100%)                  1 (100%)     2 (100%)                              
   Urinary Bladder                                    (50)         (49)         (49)         (50)                                   
      Hemorrhage                                       1 (2%)                                                                       
      Inflammation, Chronic                            1 (2%)                                                                       
      Inflammation, Suppurative                        1 (2%)                                                                       
      Necrosis                                         1 (2%)                                                                       
      Ulcer                                            1 (2%)                                                                       
      Transitional Epithelium, Hyperplasia             3 (6%)       1 (2%)       3 (6%)       6 (12%)                               
                                                                                                                                    
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page   14                                                              
                                                                                                                                   
                             ------------------------------------------------------------                                           
                             ----------              END OF REPORT             ----------                                           
                             ------------------------------------------------------------                                           
NTP is located at the National Institute of Environmental Health Sciences, part of the National Institutes of Health.