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https://ntp.niehs.nih.gov/go/3922

TDMS Study 88034-05 Pathology Tables


                                     INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)
                                                               OZONE


NTP Experiment-Test: 88034-05                                                                                     Report: PEIRPT03
Study Type: CHRONIC 30-MONTH                                                                                      Date: 05/08/95
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 21:42:15




       Facility:  Battelle Northwest

       Chemical CAS #:  10028-15-6

       Lock Date:  03/24/93

       Cage Range:  All

       Reasons For Removal:    All

       Removal Date Range:     All

       Treatment Groups:       Include All
































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

                                                             Page   1

NTP Experiment-Test: 88034-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC 30-MONTH                                      OZONE                                           Date: 05/08/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 21:42:15  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS FEMALE                   CONTROL      0.5 PPM      1.0 PPM                                                
                                                                                                                                    
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially In Study                          56           56           56                                                  
  Scheduled Sacrifice                                  6            6            6                                                  
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                36           37           40                                                  
    Natural Death                                      8            7            3                                                  
  Survivors                                                                                                                         
    Terminal Sacrifice                                 6            6            7                                                  
  Animals Examined Microscopically                    50           50           50                                                  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Intestine Large, Colon                             (49)         (50)         (50)                                                
      Parasite Metazoan                                3 (6%)       5 (10%)      4 (8%)                                             
   Intestine Large, Rectum                            (48)         (50)         (47)                                                
      Parasite Metazoan                                2 (4%)       4 (8%)       5 (11%)                                            
   Intestine Large, Cecum                             (48)         (49)         (50)                                                
      Inflammation, Acute                                           1 (2%)                                                          
      Necrosis                                                      1 (2%)                                                          
      Parasite Metazoan                                3 (6%)       3 (6%)       5 (10%)                                            
   Intestine Small, Jejunum                           (47)         (47)         (49)                                                
      Hyperplasia, Adenomatous                         1 (2%)                                                                       
   Liver                                              (50)         (50)         (50)                                                
      Angiectasis                                      1 (2%)       7 (14%)      3 (6%)                                             
      Basophilic Focus                                37 (74%)     39 (78%)     42 (84%)                                            
      Clear Cell Focus                                 1 (2%)       5 (10%)      5 (10%)                                            
      Degeneration, Cystic                                                       5 (10%)                                            
      Degeneration, Fatty                             18 (36%)     22 (44%)     11 (22%)                                            
      Eosinophilic Focus                               3 (6%)       3 (6%)       4 (8%)                                             
      Hematopoietic Cell Proliferation                              1 (2%)                                                          
      Hepatodiaphragmatic Nodule                       3 (6%)       7 (14%)     12 (24%)                                            
      Inflammation, Granulomatous                                   2 (4%)                                                          
      Mixed Cell Focus                                11 (22%)      8 (16%)      9 (18%)                                            
      Necrosis                                         2 (4%)                    3 (6%)                                             
      Thrombosis                                       1 (2%)                                                                       
      Vacuolization Cytoplasmic, Focal                 1 (2%)                                                                       
      Bile Duct, Hyperplasia                          15 (30%)     12 (24%)     10 (20%)                                            
      Centrilobular, Necrosis                          8 (16%)      5 (10%)      5 (10%)                                            
   Mesentery                                          (11)         (7)          (4)                                                 
      Inflammation, Chronic Active                     1 (9%)                                                                       
      Artery, Inflammation, Chronic Active                          1 (14%)                                                         
      Artery, Mineralization                           1 (9%)       1 (14%)                                                         
      Fat, Necrosis                                    6 (55%)      6 (86%)      4 (100%)                                           
   Oral Mucosa                                        (2)          (2)                                                              
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    2                                                              
NTP Experiment-Test: 88034-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC 30-MONTH                                      OZONE                                           Date: 05/08/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 21:42:15  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS FEMALE                   CONTROL      0.5 PPM      1.0 PPM                                                
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Gingival, Cyst                                   1 (50%)                                                                      
   Pancreas                                           (49)         (49)         (50)                                                
      Atrophy                                         20 (41%)     14 (29%)     21 (42%)                                            
      Basophilic Focus                                 1 (2%)       1 (2%)                                                          
      Hyperplasia                                      1 (2%)       1 (2%)       1 (2%)                                             
   Salivary Glands                                    (50)         (50)         (50)                                                
      Basophilic Focus                                                           1 (2%)                                             
   Stomach, Forestomach                               (49)         (50)         (50)                                                
      Hyperplasia, Squamous                            2 (4%)                    3 (6%)                                             
      Mineralization                                   1 (2%)                                                                       
      Necrosis                                        11 (22%)      9 (18%)      7 (14%)                                            
   Stomach, Glandular                                 (49)         (50)         (50)                                                
      Inflammation, Acute                              1 (2%)                                                                       
      Mineralization                                   3 (6%)       2 (4%)       4 (8%)                                             
      Necrosis                                         2 (4%)       2 (4%)       1 (2%)                                             
   Tongue                                                          (1)          (1)                                                 
      Hyperplasia                                                   1 (100%)                                                        
   Tooth                                                           (1)                                                              
      Developmental Malformation                                    1 (100%)                                                        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Blood Vessel                                       (1)          (1)          (1)                                                 
      Aorta, Mineralization                            1 (100%)     1 (100%)     1 (100%)                                           
   Heart                                              (50)         (50)         (50)                                                
      Cardiomyopathy                                  30 (60%)     35 (70%)     35 (70%)                                            
      Artery, Mineralization                           1 (2%)       1 (2%)       1 (2%)                                             
      Atrium, Thrombosis                               1 (2%)       4 (8%)       1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (50)         (49)         (50)                                                
      Atrophy                                          1 (2%)       3 (6%)       1 (2%)                                             
      Hyperplasia                                     19 (38%)     25 (51%)     22 (44%)                                            
      Hypertrophy                                      6 (12%)      5 (10%)      6 (12%)                                            
      Necrosis                                         1 (2%)       1 (2%)       1 (2%)                                             
      Thrombosis                                       1 (2%)       2 (4%)                                                          
      Vacuolization Cytoplasmic                        9 (18%)      7 (14%)      8 (16%)                                            
   Adrenal Medulla                                    (50)         (49)         (50)                                                
      Hyperplasia                                     12 (24%)     18 (37%)     13 (26%)                                            
   Islets, Pancreatic                                 (49)         (49)         (50)                                                
      Hyperplasia                                      2 (4%)       1 (2%)       1 (2%)                                             
   Parathyroid Gland                                  (49)         (48)         (44)                                                
      Hyperplasia                                      4 (8%)       2 (4%)       2 (5%)                                             
   Pituitary Gland                                    (50)         (49)         (50)                                                
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    3                                                              
NTP Experiment-Test: 88034-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC 30-MONTH                                      OZONE                                           Date: 05/08/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 21:42:15  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS FEMALE                   CONTROL      0.5 PPM      1.0 PPM                                                
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ENDOCRINE SYSTEM - CONT                                                                                                             
      Cyst                                             1 (2%)                    2 (4%)                                             
      Pars Distalis, Hyperplasia                       3 (6%)       5 (10%)     10 (20%)                                            
   Thyroid Gland                                      (50)         (49)         (50)                                                
      C-Cell, Hyperplasia                             37 (74%)     38 (78%)     30 (60%)                                            
      Follicular Cell, Hyperplasia                     1 (2%)                    1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Clitoral Gland                                     (45)         (48)         (47)                                                
      Hyperplasia                                                                1 (2%)                                             
      Inflammation, Chronic Active                     4 (9%)       3 (6%)       2 (4%)                                             
   Ovary                                              (50)         (50)         (50)                                                
      Cyst                                             3 (6%)       3 (6%)                                                          
      Hyperplasia                                                                1 (2%)                                             
   Uterus                                             (50)         (50)         (50)                                                
      Cyst                                             1 (2%)                                                                       
      Thrombosis                                                    1 (2%)                                                          
      Endometrium, Hyperplasia                                      1 (2%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (50)         (49)         (50)                                                
      Atrophy                                          1 (2%)                    1 (2%)                                             
      Inflammation, Granulomatous                                   1 (2%)       1 (2%)                                             
      Thrombosis                                                    1 (2%)                                                          
   Lymph Node                                         (10)         (12)         (9)                                                 
      Pancreatic, Inflammation, Granulomatous                       1 (8%)                                                          
      Renal, Hemorrhage                                1 (10%)      1 (8%)                                                          
      Renal, Infiltration Cellular, Plasma Cell                                  1 (11%)                                            
      Renal, Inflammation, Granulomatous               1 (10%)                                                                      
   Lymph Node, Mandibular                             (47)         (44)         (46)                                                
      Infiltration Cellular, Plasma Cell               4 (9%)       1 (2%)       1 (2%)                                             
   Spleen                                             (50)         (50)         (50)                                                
      Depletion Cellular                                            1 (2%)                                                          
      Fibrosis                                         6 (12%)      6 (12%)      3 (6%)                                             
      Hematopoietic Cell Proliferation                 1 (2%)       2 (4%)       2 (4%)                                             
      Hemorrhage                                                    2 (4%)                                                          
      Necrosis                                                      1 (2%)                                                          
      Thrombosis                                       1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    4                                                              
NTP Experiment-Test: 88034-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC 30-MONTH                                      OZONE                                           Date: 05/08/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 21:42:15  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS FEMALE                   CONTROL      0.5 PPM      1.0 PPM                                                
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (50)         (50)         (50)                                                
      Galactocele                                      1 (2%)                    3 (6%)                                             
   Skin                                               (49)         (50)         (50)                                                
      Cyst                                             1 (2%)                                                                       
      Hyperkeratosis                                   1 (2%)                                                                       
      Inflammation, Chronic Active                     6 (12%)      5 (10%)      2 (4%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (50)         (50)         (50)                                                
      Fibrous Osteodystrophy                           1 (2%)       3 (6%)       2 (4%)                                             
      Fracture                                         1 (2%)                                                                       
      Hyperostosis                                     2 (4%)       6 (12%)      2 (4%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (50)         (50)         (50)                                                
      Gliosis                                                                    1 (2%)                                             
      Hemorrhage                                       2 (4%)       1 (2%)                                                          
      Mineralization                                   1 (2%)                    1 (2%)                                             
      Necrosis                                         1 (2%)                                                                       
      Thrombosis                                       1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Larynx                                             (49)         (47)         (50)                                                
      Inflammation, Chronic Active                     1 (2%)                                                                       
      Epiglottis, Metaplasia, Squamous                 2 (4%)      16 (34%)     48 (96%)                                            
   Lung                                               (50)         (50)         (50)                                                
      Congestion, Chronic                                           1 (2%)                                                          
      Hemorrhage                                                    1 (2%)                                                          
      Inflammation, Chronic Active                     1 (2%)       1 (2%)       2 (4%)                                             
      Mineralization                                   1 (2%)       1 (2%)       1 (2%)                                             
      Alveolar Epithelium, Hyperplasia                 4 (8%)       5 (10%)      2 (4%)                                             
      Alveolar Epithelium, Metaplasia                              44 (88%)     50 (100%)                                           
      Alveolus, Infiltration Cellular, Histiocyte                  38 (76%)     49 (98%)                                            
      Artery, Infiltration Cellular, Histiocyte        1 (2%)                                                                       
      Artery, Mediastinum, Mineralization              1 (2%)       1 (2%)       1 (2%)                                             
      Artery, Perivascular, Inflammation, Chronic      1 (2%)                                                                       
      Interstitium, Fibrosis                                       41 (82%)     50 (100%)                                           
   Nose                                               (50)         (49)         (50)                                                
      Inflammation, Suppurative                        6 (12%)      7 (14%)     10 (20%)                                            
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    5                                                              
NTP Experiment-Test: 88034-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC 30-MONTH                                      OZONE                                           Date: 05/08/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 21:42:15  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS FEMALE                   CONTROL      0.5 PPM      1.0 PPM                                                
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
RESPIRATORY SYSTEM - CONT                                                                                                           
      Thrombosis                                       8 (16%)      7 (14%)      3 (6%)                                             
      Goblet Cell, Lateral Wall, Hyperplasia                       47 (96%)     50 (100%)                                           
      Lateral Wall, Hyperplasia                        4 (8%)      49 (100%)    50 (100%)                                           
      Lateral Wall, Metaplasia, Squamous               5 (10%)     25 (51%)     35 (70%)                                            
      Olfactory Epithelium, Degeneration, Hyaline     48 (96%)     48 (98%)     50 (100%)                                           
      Olfactory Epithelium, Metaplasia                              3 (6%)       4 (8%)                                             
   Trachea                                            (50)         (50)         (50)                                                
      Mineralization                                                             1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                             (1)          (2)                                                 
      Cataract                                                                   1 (50%)                                            
      Degeneration                                                               2 (100%)                                           
      Cornea, Inflammation, Chronic Active                          1 (100%)                                                        
      Cornea, Mineralization                                        1 (100%)                                                        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (50)         (50)         (50)                                                
      Cyst                                             1 (2%)                                                                       
      Infarct                                          1 (2%)                                                                       
      Mineralization                                   1 (2%)       1 (2%)       1 (2%)                                             
      Nephropathy                                     49 (98%)     47 (94%)     49 (98%)                                            
      Thrombosis                                                                 1 (2%)                                             
      Pelvis, Dilatation                               1 (2%)       1 (2%)                                                          
      Pelvis, Inflammation, Acute                                                1 (2%)                                             
      Renal Tubule, Hyperplasia                        1 (2%)       1 (2%)       1 (2%)                                             
      Renal Tubule, Necrosis                           1 (2%)       1 (2%)                                                          
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    6                                                              
NTP Experiment-Test: 88034-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC 30-MONTH                                      OZONE                                           Date: 05/08/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 21:42:15  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     CONTROL      0.5 PPM      1.0 PPM                                                
                                                                                                                                    
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially In Study                          56           56           56                                                  
  Scheduled Sacrifice                                  6            6            6                                                  
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                47           43           42                                                  
    Natural Death                                      3            7            7                                                  
  Survivors                                                                                                                         
    Terminal Sacrifice                                                           1                                                  
  Animals Examined Microscopically                    50           50           50                                                  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Intestine Large, Colon                             (49)         (50)         (49)                                                
      Mineralization                                   5 (10%)                                                                      
      Parasite Metazoan                                2 (4%)       2 (4%)       3 (6%)                                             
   Intestine Large, Rectum                            (50)         (50)         (49)                                                
      Parasite Metazoan                                             3 (6%)       2 (4%)                                             
   Intestine Large, Cecum                             (49)         (50)         (49)                                                
      Inflammation, Acute                              1 (2%)       1 (2%)       1 (2%)                                             
      Mineralization                                   2 (4%)                                                                       
      Parasite Metazoan                                3 (6%)       5 (10%)      4 (8%)                                             
      Artery, Inflammation, Chronic Active                          1 (2%)                                                          
   Intestine Small, Duodenum                          (50)         (48)         (49)                                                
      Inflammation, Acute                                           2 (4%)                                                          
   Intestine Small, Ileum                             (49)         (47)         (48)                                                
      Inflammation, Acute                              1 (2%)                                                                       
      Mineralization                                   3 (6%)                                                                       
   Liver                                              (50)         (50)         (50)                                                
      Angiectasis                                      2 (4%)       6 (12%)      3 (6%)                                             
      Basophilic Focus                                23 (46%)     18 (36%)     23 (46%)                                            
      Clear Cell Focus                                 1 (2%)                                                                       
      Degeneration, Cystic                            15 (30%)     13 (26%)     16 (32%)                                            
      Degeneration, Fatty                             14 (28%)     13 (26%)      9 (18%)                                            
      Eosinophilic Focus                               1 (2%)       1 (2%)       5 (10%)                                            
      Hepatodiaphragmatic Nodule                       3 (6%)       2 (4%)       6 (12%)                                            
      Infiltration Cellular, Mixed Cell                             1 (2%)                                                          
      Mixed Cell Focus                                 3 (6%)       2 (4%)       1 (2%)                                             
      Necrosis                                         1 (2%)       4 (8%)       3 (6%)                                             
      Thrombosis                                       2 (4%)                    1 (2%)                                             
      Vacuolization Cytoplasmic, Focal                 1 (2%)       2 (4%)                                                          
      Bile Duct, Hyperplasia                          39 (78%)     38 (76%)     29 (58%)                                            
      Centrilobular, Necrosis                          7 (14%)     10 (20%)      6 (12%)                                            
   Mesentery                                          (16)         (17)         (7)                                                 
      Inflammation, Chronic Active                     1 (6%)                                                                       
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    7                                                              
NTP Experiment-Test: 88034-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC 30-MONTH                                      OZONE                                           Date: 05/08/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 21:42:15  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     CONTROL      0.5 PPM      1.0 PPM                                                
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Artery, Inflammation, Chronic Active                          1 (6%)                                                          
      Artery, Mineralization                           6 (38%)      3 (18%)                                                         
      Fat, Hemorrhage                                                            1 (14%)                                            
      Fat, Necrosis                                    8 (50%)     10 (59%)      4 (57%)                                            
   Oral Mucosa                                                                  (4)                                                 
      Gingival, Hyperplasia, Squamous                                            1 (25%)                                            
   Pancreas                                           (50)         (50)         (50)                                                
      Atrophy                                         28 (56%)     28 (56%)     28 (56%)                                            
      Basophilic Focus                                              1 (2%)       2 (4%)                                             
      Hyperplasia                                      3 (6%)       3 (6%)                                                          
      Inflammation, Suppurative                                     1 (2%)                                                          
      Thrombosis                                       1 (2%)                                                                       
      Artery, Inflammation                             1 (2%)                                                                       
      Artery, Mineralization                           2 (4%)                                                                       
   Salivary Glands                                    (50)         (49)         (50)                                                
      Artery, Mineralization                           1 (2%)                                                                       
      Duct, Metaplasia, Squamous                                                 1 (2%)                                             
   Stomach, Forestomach                               (50)         (50)         (50)                                                
      Diverticulum                                                  1 (2%)       1 (2%)                                             
      Hyperplasia, Squamous                                         1 (2%)       2 (4%)                                             
      Mineralization                                   7 (14%)      2 (4%)                                                          
      Necrosis                                         9 (18%)     10 (20%)      5 (10%)                                            
   Stomach, Glandular                                 (50)         (50)         (50)                                                
      Inflammation, Acute                                           1 (2%)                                                          
      Mineralization                                  13 (26%)      7 (14%)      6 (12%)                                            
      Necrosis                                         6 (12%)      4 (8%)       2 (4%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Blood Vessel                                       (9)          (4)          (4)                                                 
      Aorta, Mineralization                            9 (100%)     4 (100%)     4 (100%)                                           
   Heart                                              (50)         (50)         (50)                                                
      Cardiomyopathy                                  40 (80%)     44 (88%)     39 (78%)                                            
      Inflammation, Chronic Active                                  1 (2%)                                                          
      Mineralization                                   1 (2%)                                                                       
      Artery, Mineralization                           8 (16%)      6 (12%)      2 (4%)                                             
      Atrium, Thrombosis                               7 (14%)      3 (6%)       1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (50)         (49)         (50)                                                
      Atrophy                                          1 (2%)       2 (4%)                                                          
      Hyperplasia                                     18 (36%)     22 (45%)     25 (50%)                                            
      Hypertrophy                                      7 (14%)      5 (10%)      1 (2%)                                             
      Necrosis                                                      1 (2%)       1 (2%)                                             
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    8                                                              
NTP Experiment-Test: 88034-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC 30-MONTH                                      OZONE                                           Date: 05/08/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 21:42:15  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     CONTROL      0.5 PPM      1.0 PPM                                                
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ENDOCRINE SYSTEM - CONT                                                                                                             
      Vacuolization Cytoplasmic                        5 (10%)      2 (4%)       4 (8%)                                             
   Adrenal Medulla                                    (50)         (49)         (50)                                                
      Hyperplasia                                     21 (42%)     19 (39%)     14 (28%)                                            
   Islets, Pancreatic                                 (50)         (50)         (50)                                                
      Hyperplasia                                      2 (4%)       4 (8%)       3 (6%)                                             
   Parathyroid Gland                                  (49)         (50)         (50)                                                
      Hyperplasia                                     15 (31%)     10 (20%)     12 (24%)                                            
   Pituitary Gland                                    (50)         (48)         (50)                                                
      Hemorrhage                                                                 1 (2%)                                             
      Mineralization                                   1 (2%)                    1 (2%)                                             
      Thrombosis                                       1 (2%)       1 (2%)                                                          
      Pars Distalis, Hyperplasia                       7 (14%)      9 (19%)      8 (16%)                                            
      Pars Distalis, Necrosis                                       1 (2%)                                                          
   Thyroid Gland                                      (50)         (50)         (50)                                                
      C-Cell, Hyperplasia                             28 (56%)     29 (58%)     22 (44%)                                            
      Follicular Cell, Hyperplasia                     1 (2%)       2 (4%)       3 (6%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Epididymis                                         (50)         (50)         (50)                                                
      Granuloma Sperm                                  2 (4%)                    1 (2%)                                             
   Penis                                              (4)          (4)          (1)                                                 
      Inflammation, Acute                              1 (25%)      2 (50%)                                                         
   Preputial Gland                                    (50)         (48)         (50)                                                
      Inflammation, Chronic Active                     5 (10%)      2 (4%)       6 (12%)                                            
   Prostate                                           (50)         (50)         (50)                                                
      Hyperplasia                                      6 (12%)      1 (2%)       4 (8%)                                             
      Inflammation, Chronic Active                    10 (20%)      3 (6%)       4 (8%)                                             
   Seminal Vesicle                                    (50)         (50)         (50)                                                
      Inflammation, Chronic Active                     1 (2%)                                                                       
      Mineralization                                   3 (6%)       2 (4%)                                                          
   Testes                                             (50)         (50)         (50)                                                
      Atrophy                                          9 (18%)      5 (10%)      1 (2%)                                             
      Artery, Inflammation, Chronic Active             4 (8%)       3 (6%)       3 (6%)                                             
      Artery, Mineralization                           1 (2%)                                                                       
      Interstitial Cell, Hyperplasia                  10 (20%)      4 (8%)      10 (20%)                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    9                                                              
NTP Experiment-Test: 88034-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC 30-MONTH                                      OZONE                                           Date: 05/08/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 21:42:15  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     CONTROL      0.5 PPM      1.0 PPM                                                
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Lymph Node                                         (20)         (13)         (13)                                                
      Iliac, Infiltration Cellular, Plasma Cell                                  1 (8%)                                             
      Lumbar, Hemorrhage                                            1 (8%)                                                          
      Renal, Hemorrhage                                7 (35%)      4 (31%)                                                         
      Renal, Pigmentation                                           1 (8%)                                                          
   Lymph Node, Bronchial                              (36)         (37)         (36)                                                
      Hemorrhage                                                    1 (3%)                                                          
   Lymph Node, Mandibular                             (48)         (47)         (47)                                                
      Hemorrhage                                                    1 (2%)       1 (2%)                                             
      Infiltration Cellular, Plasma Cell               3 (6%)                                                                       
      Necrosis                                                                   1 (2%)                                             
   Lymph Node, Mesenteric                             (49)         (49)         (49)                                                
      Ectasia                                          1 (2%)                                                                       
   Lymph Node, Mediastinal                            (45)         (48)         (47)                                                
      Hemorrhage                                                    2 (4%)                                                          
   Spleen                                             (50)         (50)         (50)                                                
      Fibrosis                                        16 (32%)      6 (12%)     13 (26%)                                            
      Hematopoietic Cell Proliferation                              1 (2%)                                                          
      Hemorrhage                                       1 (2%)       1 (2%)       3 (6%)                                             
      Necrosis                                         1 (2%)       1 (2%)       2 (4%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (31)         (21)         (26)                                                
      Galactocele                                      4 (13%)                   1 (4%)                                             
      Hyperplasia, Atypical                            1 (3%)                                                                       
      Inflammation, Chronic Active                     1 (3%)                                                                       
   Skin                                               (50)         (50)         (49)                                                
      Cyst                                                                       1 (2%)                                             
      Fibrosis                                         1 (2%)                                                                       
      Hyperkeratosis                                   4 (8%)                                                                       
      Inflammation, Chronic Active                    16 (32%)      3 (6%)       5 (10%)                                            
      Prepuce, Inflammation, Acute                                  1 (2%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (50)         (50)         (50)                                                
      Fibrous Osteodystrophy                          15 (30%)      8 (16%)      5 (10%)                                            
      Hyperostosis                                                  1 (2%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   10                                                              
NTP Experiment-Test: 88034-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC 30-MONTH                                      OZONE                                           Date: 05/08/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 21:42:15  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     CONTROL      0.5 PPM      1.0 PPM                                                
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (50)         (50)         (50)                                                
      Hemorrhage                                                                 2 (4%)                                             
      Mineralization                                                1 (2%)       1 (2%)                                             
      Necrosis                                                      1 (2%)       1 (2%)                                             
      Pigmentation, Hemosiderin                        1 (2%)                                                                       
      Meninges, Hyperplasia                                                      1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Larynx                                             (50)         (48)         (47)                                                
      Mineralization                                   5 (10%)      1 (2%)                                                          
      Epiglottis, Metaplasia, Squamous                             20 (42%)     43 (91%)                                            
   Lung                                               (50)         (50)         (50)                                                
      Congestion, Chronic                              1 (2%)       1 (2%)                                                          
      Foreign Body                                                  1 (2%)                                                          
      Hemorrhage                                       2 (4%)       2 (4%)       3 (6%)                                             
      Inflammation, Chronic Active                     3 (6%)                    1 (2%)                                             
      Inflammation, Suppurative                                     1 (2%)       1 (2%)                                             
      Mineralization                                  10 (20%)      6 (12%)      4 (8%)                                             
      Necrosis                                         1 (2%)                                                                       
      Thrombosis                                       1 (2%)                    1 (2%)                                             
      Alveolar Epithelium, Hyperplasia                 4 (8%)       4 (8%)       6 (12%)                                            
      Alveolar Epithelium, Metaplasia                              45 (90%)     50 (100%)                                           
      Alveolus, Infiltration Cellular, Histiocyte                  38 (76%)     49 (98%)                                            
      Artery, Mediastinum, Mineralization              7 (14%)      1 (2%)       1 (2%)                                             
      Artery, Mediastinum, Thrombosis                  1 (2%)                                                                       
      Interstitium, Fibrosis                                       44 (88%)     50 (100%)                                           
   Nose                                               (50)         (49)         (49)                                                
      Inflammation, Suppurative                       14 (28%)     13 (27%)     18 (37%)                                            
      Thrombosis                                      11 (22%)      6 (12%)      3 (6%)                                             
      Goblet Cell, Lateral Wall, Hyperplasia           1 (2%)      46 (94%)     48 (98%)                                            
      Lateral Wall, Hyperplasia                       10 (20%)     48 (98%)     47 (96%)                                            
      Lateral Wall, Metaplasia, Squamous              10 (20%)     23 (47%)     40 (82%)                                            
      Olfactory Epithelium, Degeneration, Hyaline     49 (98%)     49 (100%)    49 (100%)                                           
      Olfactory Epithelium, Metaplasia                 5 (10%)      1 (2%)                                                          
   Trachea                                            (50)         (50)         (50)                                                
      Mineralization                                   3 (6%)                    2 (4%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                (1)          (2)          (3)                                                 
      Cataract                                                      1 (50%)      2 (67%)                                            
      Degeneration                                     1 (100%)     1 (50%)      2 (67%)                                            
      Retina, Atrophy                                               1 (50%)      1 (33%)                                            
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   11                                                              
NTP Experiment-Test: 88034-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC 30-MONTH                                      OZONE                                           Date: 05/08/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 21:42:15  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     CONTROL      0.5 PPM      1.0 PPM                                                
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
SPECIAL SENSES SYSTEM - CONT                                                                                                        
   Harderian Gland                                                              (1)                                                 
      Inflammation, Chronic Active                                               1 (100%)                                           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (50)         (50)         (50)                                                
      Cyst                                             3 (6%)       3 (6%)       3 (6%)                                             
      Hyperplasia, Oncocytic                           1 (2%)                                                                       
      Mineralization                                  10 (20%)      5 (10%)      2 (4%)                                             
      Nephropathy                                     50 (100%)    49 (98%)     50 (100%)                                           
      Pelvis, Dilatation                               1 (2%)                                                                       
      Pelvis, Inflammation, Acute                      1 (2%)                                                                       
      Renal Tubule, Hyperplasia                        6 (12%)      4 (8%)       3 (6%)                                             
      Renal Tubule, Hyperplasia, Oncocytic             1 (2%)       1 (2%)                                                          
      Transitional Epithelium, Hyperplasia             2 (4%)                                                                       
   Urinary Bladder                                    (50)         (50)         (49)                                                
      Hemorrhage                                       1 (2%)                                                                       
      Infiltration Cellular, Polymorphonuclear                      1 (2%)       1 (2%)                                             
      Inflammation, Chronic Active                     2 (4%)                                                                       
      Transitional Epithelium, Hyperplasia             2 (4%)                                                                       
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   12                                                              
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