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https://ntp.niehs.nih.gov/go/4416

TDMS Study 88034-03 Pathology Tables


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


NTP Experiment-Test: 88034-03                                                                                     Report: PEIRPT03
Study Type: CHRONIC                                                                                               Date: 05/08/95
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 19:53:30




       Facility:  Battelle Northwest

       Chemical CAS #:  10028-15-6

       Lock Date:  02/17/93

       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: 88034-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                               OZONE                                           Date: 05/08/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 19:53:30  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS FEMALE                   CONTROL      0.12 PPM     0.5 PPM      1.0 PPM                                   
                                                                                                                                    
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially In Study                          56           56           56           56                                     
  Scheduled Sacrifice                                  6            6            6            6                                     
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                19           22           17           16                                     
    Natural Death                                      3            4            3            7                                     
  Survivors                                                                                                                         
    Terminal Sacrifice                                28           24           30           27                                     
  Animals Examined Microscopically                    50           50           50           50                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Intestine Large, Colon                             (50)         (50)         (50)         (49)                                   
      Cyst                                                                                    1 (2%)                                
      Parasite Metazoan                                2 (4%)       2 (4%)       3 (6%)       5 (10%)                               
   Intestine Large, Rectum                            (43)         (48)         (45)         (48)                                   
      Parasite Metazoan                                4 (9%)       4 (8%)       3 (7%)       1 (2%)                                
   Intestine Large, Cecum                             (50)         (50)         (50)         (50)                                   
      Parasite Metazoan                                4 (8%)       2 (4%)       8 (16%)      9 (18%)                               
   Intestine Small, Duodenum                          (50)         (50)         (50)         (49)                                   
      Parasite Metazoan                                                          1 (2%)                                             
   Intestine Small, Ileum                             (50)         (49)         (48)         (47)                                   
      Parasite Metazoan                                1 (2%)       1 (2%)                                                          
   Liver                                              (50)         (50)         (50)         (50)                                   
      Angiectasis                                      1 (2%)       2 (4%)                    4 (8%)                                
      Basophilic Focus                                38 (76%)     34 (68%)     35 (70%)     38 (76%)                               
      Clear Cell Focus                                 6 (12%)      5 (10%)      5 (10%)      4 (8%)                                
      Degeneration, Fatty                             13 (26%)      6 (12%)      8 (16%)      4 (8%)                                
      Eosinophilic Focus                               3 (6%)       1 (2%)                    2 (4%)                                
      Hepatodiaphragmatic Nodule                       7 (14%)      6 (12%)      6 (12%)     15 (30%)                               
      Mixed Cell Focus                                 5 (10%)     13 (26%)      6 (12%)      7 (14%)                               
      Necrosis                                         1 (2%)                    1 (2%)                                             
      Regeneration                                                                            1 (2%)                                
      Bile Duct, Hyperplasia                          10 (20%)     11 (22%)      8 (16%)     11 (22%)                               
      Centrilobular, Necrosis                          2 (4%)       4 (8%)       3 (6%)       1 (2%)                                
      Serosa, Fibrosis                                                           1 (2%)                                             
   Mesentery                                          (4)          (5)          (11)         (4)                                    
      Hemorrhage                                       1 (25%)                                                                      
      Artery, Inflammation, Chronic Active             1 (25%)                   1 (9%)       1 (25%)                               
      Artery, Mineralization                           1 (25%)                                                                      
      Fat, Necrosis                                    2 (50%)      5 (100%)     9 (82%)      3 (75%)                               
   Oral Mucosa                                        (1)          (1)                                                              
      Pharyngeal, Hyperplasia                          1 (100%)                                                                     
   Pancreas                                           (50)         (50)         (50)         (49)                                   
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    2                                                              
NTP Experiment-Test: 88034-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                               OZONE                                           Date: 05/08/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 19:53:30  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS FEMALE                   CONTROL      0.12 PPM     0.5 PPM      1.0 PPM                                   
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Atrophy                                         22 (44%)     14 (28%)     18 (36%)     20 (41%)                               
      Basophilic Focus                                 2 (4%)       1 (2%)       1 (2%)       1 (2%)                                
      Metaplasia, Hepatocyte                                        1 (2%)                                                          
      Artery, Inflammation                                                                    1 (2%)                                
   Salivary Glands                                    (50)         (50)         (50)         (50)                                   
      Atrophy                                          1 (2%)                                                                       
      Duct, Metaplasia, Squamous                                                              1 (2%)                                
   Stomach, Forestomach                               (50)         (50)         (50)         (50)                                   
      Diverticulum                                     1 (2%)                                 1 (2%)                                
      Hyperplasia, Squamous                                                      1 (2%)       1 (2%)                                
      Mineralization                                                             2 (4%)                                             
      Necrosis                                         2 (4%)       4 (8%)       4 (8%)       3 (6%)                                
   Stomach, Glandular                                 (50)         (50)         (50)         (50)                                   
      Inflammation, Acute                                                                     1 (2%)                                
      Mineralization                                   5 (10%)      4 (8%)       5 (10%)      7 (14%)                               
      Necrosis                                                      4 (8%)       2 (4%)       2 (4%)                                
   Tongue                                             (1)          (1)                       (1)                                    
      Hyperplasia                                                                             1 (100%)                              
   Tooth                                                           (1)          (1)          (1)                                    
      Developmental Malformation                                    1 (100%)     1 (100%)     1 (100%)                              
      Inflammation, Chronic Active                                  1 (100%)                                                        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Blood Vessel                                       (1)                                                                           
      Aorta, Mineralization                            1 (100%)                                                                     
   Heart                                              (50)         (50)         (50)         (50)                                   
      Cardiomyopathy                                  37 (74%)     32 (64%)     34 (68%)     30 (60%)                               
      Artery, Mineralization                           1 (2%)                                                                       
      Atrium, Thrombosis                               1 (2%)       1 (2%)       2 (4%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (50)         (50)         (50)         (50)                                   
      Hyperplasia                                     21 (42%)     22 (44%)     22 (44%)     23 (46%)                               
      Hypertrophy                                     12 (24%)     13 (26%)      9 (18%)      7 (14%)                               
      Mineralization                                                                          1 (2%)                                
      Necrosis                                         1 (2%)                                 1 (2%)                                
      Vacuolization Cytoplasmic                                                  2 (4%)                                             
   Adrenal Medulla                                    (50)         (50)         (50)         (50)                                   
      Hyperplasia                                      9 (18%)     10 (20%)     11 (22%)      5 (10%)                               
   Parathyroid Gland                                  (49)         (48)         (46)         (49)                                   
      Hyperplasia                                      3 (6%)       1 (2%)       3 (7%)       1 (2%)                                
   Pituitary Gland                                    (50)         (49)         (50)         (49)                                   
      Cyst                                             5 (10%)                   1 (2%)                                             
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    3                                                              
NTP Experiment-Test: 88034-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                               OZONE                                           Date: 05/08/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 19:53:30  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS FEMALE                   CONTROL      0.12 PPM     0.5 PPM      1.0 PPM                                   
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ENDOCRINE SYSTEM - CONT                                                                                                             
      Pars Distalis, Hyperplasia                      13 (26%)      8 (16%)      7 (14%)     10 (20%)                               
      Pars Intermedia, Hyperplasia                                  1 (2%)                                                          
   Thyroid Gland                                      (50)         (50)         (50)         (50)                                   
      C-Cell, Hyperplasia                             43 (86%)     38 (76%)     34 (68%)     31 (62%)                               
      Follicular Cell, Hyperplasia                     2 (4%)                    4 (8%)       1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Clitoral Gland                                     (43)         (50)         (47)         (47)                                   
      Cyst                                                                                    1 (2%)                                
      Hyperplasia                                                   1 (2%)       2 (4%)                                             
      Inflammation, Chronic Active                                  3 (6%)       2 (4%)       4 (9%)                                
   Ovary                                              (50)         (50)         (49)         (49)                                   
      Angiectasis                                      1 (2%)                                                                       
      Cyst                                             1 (2%)       2 (4%)      11 (22%)      1 (2%)                                
      Hemorrhage                                                                              1 (2%)                                
      Inflammation, Granulomatous                      2 (4%)                    1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (50)         (50)         (50)         (50)                                   
      Hyperplasia, Reticulum Cell                      1 (2%)       2 (4%)                    4 (8%)                                
   Lymph Node                                         (5)          (9)          (3)          (3)                                    
      Renal, Hemorrhage                                             1 (11%)                   1 (33%)                               
      Renal, Inflammation, Granulomatous                            1 (11%)      1 (33%)                                            
   Lymph Node, Mandibular                             (48)         (47)         (46)         (46)                                   
      Infiltration Cellular, Plasma Cell                            1 (2%)                    1 (2%)                                
   Lymph Node, Mesenteric                             (49)         (50)         (49)         (50)                                   
      Hemorrhage                                                    1 (2%)       1 (2%)                                             
   Lymph Node, Mediastinal                            (39)         (46)         (41)         (47)                                   
      Hemorrhage                                       1 (3%)                    1 (2%)                                             
   Spleen                                             (50)         (50)         (50)         (49)                                   
      Fibrosis                                         2 (4%)       4 (8%)       2 (4%)                                             
      Hematopoietic Cell Proliferation                 2 (4%)                    2 (4%)       2 (4%)                                
      Hemorrhage                                       1 (2%)                                 1 (2%)                                
      Necrosis                                         2 (4%)       1 (2%)                                                          
      Capsule, Fibrosis                                                          1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    4                                                              
NTP Experiment-Test: 88034-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                               OZONE                                           Date: 05/08/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 19:53:30  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS FEMALE                   CONTROL      0.12 PPM     0.5 PPM      1.0 PPM                                   
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (50)         (49)         (50)         (50)                                   
      Galactocele                                                   2 (4%)                                                          
      Hyperplasia, Atypical                            4 (8%)                    1 (2%)                                             
      Inflammation, Suppurative                                     1 (2%)                                                          
   Skin                                               (50)         (50)         (50)         (50)                                   
      Hyperkeratosis                                   1 (2%)       1 (2%)                                                          
      Inflammation, Chronic Active                     1 (2%)       2 (4%)       3 (6%)       1 (2%)                                
      Prepuce, Inflammation, Acute                     1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (50)         (50)         (50)         (50)                                   
      Fibrous Osteodystrophy                           1 (2%)                                 1 (2%)                                
      Hyperostosis                                     3 (6%)       2 (4%)       6 (12%)      6 (12%)                               
   Skeletal Muscle                                    (1)                                    (3)                                    
      Cyst                                                                                    1 (33%)                               
      Hemorrhage                                       1 (100%)                               1 (33%)                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (50)         (50)         (50)         (50)                                   
      Hemorrhage                                       1 (2%)                                                                       
      Necrosis                                                      1 (2%)                                                          
      Meninges, Hyperplasia                            1 (2%)                                 1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Larynx                                             (50)         (50)         (50)         (50)                                   
      Inflammation, Acute                              1 (2%)       1 (2%)                    1 (2%)                                
      Mineralization                                   1 (2%)                                                                       
      Epiglottis, Metaplasia, Squamous                 4 (8%)       5 (10%)      9 (18%)     43 (86%)                               
   Lung                                               (50)         (50)         (50)         (50)                                   
      Inflammation, Chronic Active                     5 (10%)      3 (6%)                                                          
      Inflammation, Suppurative                                     1 (2%)                                                          
      Mineralization                                   2 (4%)                                 1 (2%)                                
      Alveolar Epithelium, Hyperplasia                 4 (8%)       5 (10%)      5 (10%)      6 (12%)                               
      Alveolar Epithelium, Metaplasia                               6 (12%)     48 (96%)     48 (96%)                               
      Alveolus, Infiltration Cellular, Histiocyte                               31 (62%)     43 (86%)                               
      Artery, Mediastinum, Mineralization              1 (2%)                                                                       
      Interstitium, Fibrosis                                                    42 (84%)     47 (94%)                               
   Nose                                               (50)         (50)         (50)         (50)                                   
      Inflammation, Suppurative                        3 (6%)       6 (12%)      2 (4%)       2 (4%)                                
      Necrosis                                                      1 (2%)                                                          
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    5                                                              
NTP Experiment-Test: 88034-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                               OZONE                                           Date: 05/08/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 19:53:30  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS FEMALE                   CONTROL      0.12 PPM     0.5 PPM      1.0 PPM                                   
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
RESPIRATORY SYSTEM - CONT                                                                                                           
      Thrombosis                                       6 (12%)      3 (6%)       4 (8%)       3 (6%)                                
      Goblet Cell, Lateral Wall, Hyperplasia           1 (2%)       2 (4%)      45 (90%)     50 (100%)                              
      Lateral Wall, Hyperplasia                        2 (4%)       8 (16%)     48 (96%)     50 (100%)                              
      Lateral Wall, Metaplasia, Squamous               2 (4%)      11 (22%)     21 (42%)     45 (90%)                               
      Nasopharyngeal Duct, Inflammation, Acute         1 (2%)                                                                       
      Olfactory Epithelium, Degeneration, Hyaline     50 (100%)    48 (96%)     50 (100%)    47 (94%)                               
      Olfactory Epithelium, Metaplasia                              3 (6%)                                                          
   Trachea                                            (50)         (50)         (50)         (50)                                   
      Inflammation, Acute                              1 (2%)                                                                       
      Mineralization                                   1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                             (1)                       (2)                                    
      Cataract                                                                                2 (100%)                              
      Degeneration                                                  1 (100%)                                                        
      Retina, Atrophy                                                                         1 (50%)                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (50)         (50)         (50)         (50)                                   
      Cyst                                                                       1 (2%)       1 (2%)                                
      Hemorrhage                                                                              1 (2%)                                
      Infarct                                          1 (2%)                                                                       
      Mineralization                                   1 (2%)                                                                       
      Nephropathy                                     49 (98%)     48 (96%)     48 (96%)     46 (92%)                               
      Renal Tubule, Hyperplasia                                                  1 (2%)       1 (2%)                                
      Renal Tubule, Vacuolization Cytoplasmic                       1 (2%)                                                          
   Urinary Bladder                                    (50)         (49)         (49)         (50)                                   
      Hemorrhage                                                    1 (2%)                                                          
      Necrosis                                                      1 (2%)                                                          
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    6                                                              
NTP Experiment-Test: 88034-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                               OZONE                                           Date: 05/08/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 19:53:30  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     CONTROL      0.12 PPM     0.5 PPM      1.0 PPM                                   
                                                                                                                                    
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially In Study                          56           56           56           56                                     
  Scheduled Sacrifice                                  6            6            6            6                                     
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                35           40           36           36                                     
    Natural Death                                      6            5            7            7                                     
    Accidently Killed                                  1                                                                            
  Survivors                                                                                                                         
    Terminal Sacrifice                                 8            5            7            7                                     
  Animals Examined Microscopically                    50           50           50           50                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Intestine Large, Colon                             (50)         (50)         (50)         (50)                                   
      Inflammation, Chronic Active                     1 (2%)                                                                       
      Mineralization                                   1 (2%)       1 (2%)                                                          
      Parasite Metazoan                                3 (6%)       4 (8%)       9 (18%)      6 (12%)                               
   Intestine Large, Rectum                            (50)         (50)         (50)         (49)                                   
      Mineralization                                                1 (2%)                                                          
      Parasite Metazoan                                2 (4%)       2 (4%)       2 (4%)       3 (6%)                                
   Intestine Large, Cecum                             (50)         (50)         (49)         (50)                                   
      Inflammation, Chronic Active                     1 (2%)                                                                       
      Parasite Metazoan                                3 (6%)       5 (10%)      3 (6%)       5 (10%)                               
   Intestine Small, Duodenum                          (50)         (50)         (50)         (49)                                   
      Hyperplasia, Adenomatous                         1 (2%)                                                                       
      Necrosis                                         1 (2%)       3 (6%)                    1 (2%)                                
   Intestine Small, Ileum                             (50)         (50)         (49)         (48)                                   
      Inflammation, Acute                                           1 (2%)                                                          
   Liver                                              (50)         (50)         (50)         (50)                                   
      Angiectasis                                      4 (8%)       1 (2%)       2 (4%)       4 (8%)                                
      Basophilic Focus                                14 (28%)     18 (36%)     11 (22%)      9 (18%)                               
      Clear Cell Focus                                 2 (4%)       2 (4%)       1 (2%)       1 (2%)                                
      Degeneration, Cystic                            13 (26%)     16 (32%)     19 (38%)     14 (28%)                               
      Degeneration, Fatty                              9 (18%)      5 (10%)      5 (10%)      4 (8%)                                
      Eosinophilic Focus                               1 (2%)       4 (8%)       2 (4%)       2 (4%)                                
      Fibrosis                                         1 (2%)                                                                       
      Hepatodiaphragmatic Nodule                       3 (6%)       5 (10%)      2 (4%)       4 (8%)                                
      Inflammation, Granulomatous                      2 (4%)                                                                       
      Mineralization                                   1 (2%)                                                                       
      Mixed Cell Focus                                 2 (4%)       1 (2%)       4 (8%)       1 (2%)                                
      Necrosis                                         2 (4%)       3 (6%)       1 (2%)                                             
      Regeneration                                     2 (4%)                                 2 (4%)                                
      Thrombosis                                       1 (2%)                    1 (2%)                                             
      Bile Duct, Hyperplasia                          29 (58%)     34 (68%)     37 (74%)     33 (66%)                               
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    7                                                              
NTP Experiment-Test: 88034-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                               OZONE                                           Date: 05/08/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 19:53:30  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     CONTROL      0.12 PPM     0.5 PPM      1.0 PPM                                   
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Centrilobular, Necrosis                          3 (6%)       6 (12%)      3 (6%)       2 (4%)                                
   Mesentery                                          (12)         (6)          (12)         (8)                                    
      Thrombosis                                       1 (8%)                                                                       
      Artery, Inflammation, Chronic Active             1 (8%)                    1 (8%)                                             
      Artery, Mineralization                           3 (25%)      2 (33%)      1 (8%)       1 (13%)                               
      Fat, Necrosis                                    7 (58%)      4 (67%)      9 (75%)      5 (63%)                               
   Pancreas                                           (50)         (50)         (50)         (50)                                   
      Atrophy                                         22 (44%)     23 (46%)     30 (60%)     26 (52%)                               
      Basophilic Focus                                 1 (2%)                    4 (8%)                                             
      Hyperplasia                                      2 (4%)       4 (8%)       4 (8%)       2 (4%)                                
      Thrombosis                                                    1 (2%)                                                          
      Artery, Inflammation                             3 (6%)       1 (2%)       1 (2%)                                             
      Artery, Mineralization                           2 (4%)                                                                       
   Salivary Glands                                    (49)         (50)         (50)         (50)                                   
      Inflammation, Chronic                                                      1 (2%)                                             
   Stomach, Forestomach                               (50)         (50)         (50)         (50)                                   
      Diverticulum                                                               2 (4%)                                             
      Foreign Body                                                                            1 (2%)                                
      Hyperplasia, Squamous                            4 (8%)       2 (4%)       1 (2%)       3 (6%)                                
      Inflammation, Acute                              3 (6%)       1 (2%)       1 (2%)       2 (4%)                                
      Mineralization                                   2 (4%)       5 (10%)      1 (2%)       4 (8%)                                
      Necrosis                                         4 (8%)       7 (14%)      9 (18%)      7 (14%)                               
   Stomach, Glandular                                 (50)         (50)         (50)         (50)                                   
      Cyst                                                                                    1 (2%)                                
      Inflammation, Acute                              1 (2%)       1 (2%)                    1 (2%)                                
      Mineralization                                   6 (12%)      7 (14%)      7 (14%)     10 (20%)                               
      Necrosis                                         2 (4%)       4 (8%)       3 (6%)       3 (6%)                                
   Tooth                                              (2)          (2)          (1)          (2)                                    
      Developmental Malformation                       2 (100%)     2 (100%)                                                        
      Inflammation, Chronic Active                                               1 (100%)     1 (50%)                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Blood Vessel                                       (4)          (4)          (1)          (2)                                    
      Aorta, Mineralization                            4 (100%)     4 (100%)     1 (100%)     2 (100%)                              
   Heart                                              (50)         (50)         (50)         (50)                                   
      Cardiomyopathy                                  39 (78%)     37 (74%)     44 (88%)     36 (72%)                               
      Mineralization                                   1 (2%)       2 (4%)                                                          
      Thrombosis                                                    2 (4%)                                                          
      Artery, Mineralization                           3 (6%)       2 (4%)       1 (2%)       1 (2%)                                
      Atrium, Thrombosis                               2 (4%)       3 (6%)       5 (10%)      1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    8                                                              
NTP Experiment-Test: 88034-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                               OZONE                                           Date: 05/08/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 19:53:30  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     CONTROL      0.12 PPM     0.5 PPM      1.0 PPM                                   
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (50)         (50)         (50)         (50)                                   
      Accessory Adrenal Cortical Nodule                             1 (2%)                                                          
      Hyperplasia                                     24 (48%)     20 (40%)     23 (46%)     18 (36%)                               
      Hypertrophy                                      6 (12%)      7 (14%)      7 (14%)      7 (14%)                               
      Necrosis                                         2 (4%)                    2 (4%)       2 (4%)                                
      Vacuolization Cytoplasmic                        1 (2%)                                                                       
   Adrenal Medulla                                    (50)         (50)         (50)         (50)                                   
      Hyperplasia                                     23 (46%)     29 (58%)     24 (48%)     17 (34%)                               
   Islets, Pancreatic                                 (50)         (50)         (50)         (50)                                   
      Hyperplasia                                      2 (4%)       1 (2%)       2 (4%)                                             
   Parathyroid Gland                                  (49)         (49)         (48)         (47)                                   
      Hyperplasia                                     10 (20%)     10 (20%)     15 (31%)     11 (23%)                               
   Pituitary Gland                                    (50)         (50)         (49)         (49)                                   
      Cyst                                             1 (2%)                                                                       
      Mineralization                                                2 (4%)       1 (2%)                                             
      Pars Distalis, Hemorrhage                                                               1 (2%)                                
      Pars Distalis, Hyperplasia                                    3 (6%)       3 (6%)       5 (10%)                               
      Pars Distalis, Metaplasia, Osseous               1 (2%)                                                                       
      Pars Intermedia, Hyperplasia                                  1 (2%)                                                          
   Thyroid Gland                                      (49)         (50)         (50)         (50)                                   
      C-Cell, Hyperplasia                             29 (59%)     25 (50%)     31 (62%)     16 (32%)                               
      Follicular Cell, Hyperplasia                     2 (4%)       1 (2%)       2 (4%)       2 (4%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Epididymis                                         (50)         (50)         (50)         (50)                                   
      Granuloma Sperm                                  1 (2%)       1 (2%)       2 (4%)       2 (4%)                                
   Preputial Gland                                    (49)         (50)         (50)         (49)                                   
      Cyst                                                                       1 (2%)                                             
      Inflammation, Chronic Active                     4 (8%)       2 (4%)       3 (6%)       6 (12%)                               
   Prostate                                           (49)         (50)         (50)         (50)                                   
      Hyperplasia                                      1 (2%)                    1 (2%)       1 (2%)                                
      Inflammation, Chronic Active                     7 (14%)      7 (14%)      5 (10%)      6 (12%)                               
      Inflammation, Suppurative                        2 (4%)                                                                       
   Seminal Vesicle                                    (50)         (50)         (50)         (50)                                   
      Inflammation, Chronic Active                     1 (2%)                    1 (2%)                                             
      Mineralization                                                1 (2%)                                                          
   Testes                                             (50)         (50)         (50)         (50)                                   
      Atrophy                                         10 (20%)      4 (8%)       6 (12%)      6 (12%)                               
      Artery, Inflammation, Chronic Active             7 (14%)      8 (16%)      4 (8%)       3 (6%)                                
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    9                                                              
NTP Experiment-Test: 88034-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                               OZONE                                           Date: 05/08/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 19:53:30  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     CONTROL      0.12 PPM     0.5 PPM      1.0 PPM                                   
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
GENITAL SYSTEM - CONT                                                                                                               
      Interstitial Cell, Hyperplasia                  13 (26%)     13 (26%)     13 (26%)      9 (18%)                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (50)         (50)         (50)         (50)                                   
      Atrophy                                          1 (2%)                                                                       
   Lymph Node                                         (18)         (10)         (24)         (10)                                   
      Iliac, Hemorrhage                                1 (6%)                                                                       
      Renal, Angiectasis                               1 (6%)                                                                       
      Renal, Hemorrhage                                6 (33%)      2 (20%)      6 (25%)      1 (10%)                               
      Renal, Inflammation, Granulomatous                                         1 (4%)                                             
   Lymph Node, Bronchial                              (43)         (38)         (44)         (38)                                   
      Fibrosis                                                                                1 (3%)                                
      Hemorrhage                                       1 (2%)                                                                       
   Lymph Node, Mandibular                             (46)         (46)         (46)         (42)                                   
      Hemorrhage                                       1 (2%)       1 (2%)                                                          
      Infiltration Cellular, Plasma Cell               1 (2%)       2 (4%)       2 (4%)       2 (5%)                                
   Lymph Node, Mesenteric                             (49)         (49)         (50)         (50)                                   
      Ectasia                                                       1 (2%)                                                          
      Hemorrhage                                       1 (2%)                                                                       
   Lymph Node, Mediastinal                            (46)         (47)         (48)         (46)                                   
      Hemorrhage                                                    1 (2%)       1 (2%)                                             
   Spleen                                             (50)         (50)         (50)         (50)                                   
      Fibrosis                                        12 (24%)     11 (22%)     16 (32%)     14 (28%)                               
      Hematopoietic Cell Proliferation                 2 (4%)       2 (4%)       1 (2%)                                             
      Hemorrhage                                                                 1 (2%)                                             
      Hyperplasia, Focal                                                                      1 (2%)                                
      Necrosis                                         2 (4%)       5 (10%)      1 (2%)       1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (33)         (29)         (28)         (30)                                   
      Galactocele                                      2 (6%)       1 (3%)       1 (4%)       1 (3%)                                
   Skin                                               (50)         (50)         (50)         (50)                                   
      Hyperkeratosis                                   3 (6%)       3 (6%)       1 (2%)                                             
      Inflammation, Chronic Active                     2 (4%)       8 (16%)      2 (4%)       1 (2%)                                
      Prepuce, Inflammation, Acute                     3 (6%)       4 (8%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (50)         (50)         (50)         (50)                                   
      Fibrous Osteodystrophy                           7 (14%)      8 (16%)      8 (16%)      4 (8%)                                
      Hyperostosis                                                  1 (2%)                    1 (2%)                                
   Skeletal Muscle                                    (2)                       (2)          (1)                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   10                                                              
NTP Experiment-Test: 88034-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                               OZONE                                           Date: 05/08/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 19:53:30  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     CONTROL      0.12 PPM     0.5 PPM      1.0 PPM                                   
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
MUSCULOSKELETAL SYSTEM - CONT                                                                                                       
      Hemorrhage                                       1 (50%)                                                                      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (50)         (50)         (50)         (50)                                   
      Hemorrhage                                       2 (4%)                                                                       
      Necrosis                                         1 (2%)                                 1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Larynx                                             (50)         (50)         (50)         (50)                                   
      Inflammation, Acute                              1 (2%)                                                                       
      Mineralization                                   1 (2%)                                 1 (2%)                                
      Epiglottis, Metaplasia, Squamous                              2 (4%)      16 (32%)     43 (86%)                               
   Lung                                               (50)         (50)         (50)         (50)                                   
      Congestion, Chronic                                                        1 (2%)                                             
      Hemorrhage                                       2 (4%)       2 (4%)                                                          
      Inflammation, Chronic Active                     2 (4%)                                 1 (2%)                                
      Inflammation, Suppurative                                     1 (2%)                                                          
      Metaplasia, Osseous                              2 (4%)       1 (2%)       1 (2%)                                             
      Mineralization                                   3 (6%)       4 (8%)       1 (2%)       2 (4%)                                
      Thrombosis                                       1 (2%)       1 (2%)                                                          
      Alveolar Epithelium, Hyperplasia                 6 (12%)      6 (12%)      3 (6%)       4 (8%)                                
      Alveolar Epithelium, Metaplasia                               9 (18%)     46 (92%)     47 (94%)                               
      Alveolus, Edema                                  1 (2%)                                 1 (2%)                                
      Alveolus, Infiltration Cellular, Histiocyte      1 (2%)                   27 (54%)     42 (84%)                               
      Artery, Infiltration Cellular, Histiocyte        1 (2%)                                                                       
      Artery, Mediastinum, Inflammation                1 (2%)                                                                       
      Artery, Mediastinum, Mineralization              5 (10%)      3 (6%)       1 (2%)       2 (4%)                                
      Bronchiole, Necrosis                                                                    1 (2%)                                
      Interstitium, Fibrosis                                        2 (4%)      40 (80%)     44 (88%)                               
   Nose                                               (50)         (50)         (50)         (50)                                   
      Inflammation, Suppurative                        3 (6%)      10 (20%)     12 (24%)     20 (40%)                               
      Thrombosis                                       8 (16%)     13 (26%)     12 (24%)      8 (16%)                               
      Goblet Cell, Lateral Wall, Hyperplasia           1 (2%)       4 (8%)      41 (82%)     48 (96%)                               
      Lateral Wall, Hyperplasia                                     8 (16%)     50 (100%)    49 (98%)                               
      Lateral Wall, Metaplasia, Squamous               2 (4%)       6 (12%)     36 (72%)     46 (92%)                               
      Olfactory Epithelium, Degeneration, Hyaline     50 (100%)    50 (100%)    50 (100%)    50 (100%)                              
      Olfactory Epithelium, Metaplasia                 2 (4%)       2 (4%)       1 (2%)       1 (2%)                                
   Trachea                                            (50)         (50)         (50)         (50)                                   
      Inflammation, Acute                                           1 (2%)       1 (2%)                                             
      Metaplasia, Squamous                             1 (2%)                                 1 (2%)                                
      Mineralization                                   2 (4%)       1 (2%)                    2 (4%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   11                                                              
NTP Experiment-Test: 88034-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                               OZONE                                           Date: 05/08/95  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 19:53:30  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     CONTROL      0.12 PPM     0.5 PPM      1.0 PPM                                   
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                (3)          (1)          (2)                                                 
      Cataract                                         2 (67%)                   2 (100%)                                           
      Degeneration                                                  1 (100%)                                                        
      Hemorrhage                                       1 (33%)                                                                      
      Cornea, Inflammation, Chronic Active                                       1 (50%)                                            
      Cornea, Mineralization                           1 (33%)                                                                      
      Retina, Atrophy                                  2 (67%)                   1 (50%)                                            
   Zymbal's Gland                                                  (1)          (1)          (1)                                    
      Hyperplasia, Squamous                                         1 (100%)                                                        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (50)         (50)         (50)         (50)                                   
      Angiectasis                                                                1 (2%)                                             
      Cyst                                             1 (2%)       1 (2%)       3 (6%)       3 (6%)                                
      Infarct                                          1 (2%)       2 (4%)                    1 (2%)                                
      Mineralization                                   4 (8%)       5 (10%)      1 (2%)       2 (4%)                                
      Nephropathy                                     49 (98%)     48 (96%)     50 (100%)    50 (100%)                              
      Thrombosis                                       1 (2%)                    1 (2%)                                             
      Artery, Inflammation                             1 (2%)                    1 (2%)                                             
      Papilla, Necrosis                                1 (2%)                                                                       
      Pelvis, Inflammation, Acute                      2 (4%)       3 (6%)       4 (8%)       2 (4%)                                
      Pelvis, Transitional Epithelium, Hyperplasia     1 (2%)                                                                       
      Renal Tubule, Hyperplasia                        1 (2%)       3 (6%)       1 (2%)                                             
   Urinary Bladder                                    (50)         (50)         (50)         (50)                                   
      Hemorrhage                                       1 (2%)                                                                       
      Inflammation, Acute                              2 (4%)                                                                       
      Inflammation, Chronic Active                     1 (2%)       3 (6%)       4 (8%)       1 (2%)                                
      Transitional Epithelium, Hyperplasia             1 (2%)       1 (2%)                    1 (2%)                                
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   12                                                              
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                             ----------              END OF REPORT             ----------                                           
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