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https://ntp.niehs.nih.gov/go/3910

TDMS Study 88034-06 Pathology Tables


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


NTP Experiment-Test: 88034-06                                                                                     Report: PEIRPT03
Study Type: CHRONIC 30-MONTH                                                                                      Date: 05/08/95
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 22:21:59




       Facility:  Battelle Northwest

       Chemical CAS #:  10028-15-6

       Lock Date:  03/09/93

       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: 88034-06         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: 22:21:59  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        CONTROL      0.5 PPM      1.0 PPM                                                
                                                                                                                                    
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially In Study                          50           50           50                                                  
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                34           25           33                                                  
    Natural Death                                      7           13            7                                                  
  Survivors                                                                                                                         
    Terminal Sacrifice                                 9           12           10                                                  
  Animals Examined Microscopically                    50           50           50                                                  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Gallbladder                                        (43)         (38)         (44)                                                
      Inflammation, Suppurative                        1 (2%)                                                                       
      Epithelium, Hyperplasia                          2 (5%)                                                                       
   Intestine Small, Duodenum                          (45)         (41)         (46)                                                
      Necrosis                                         1 (2%)                    1 (2%)                                             
      Epithelium, Hyperplasia                          1 (2%)                                                                       
      Peyer's Patch, Hyperplasia                                                 1 (2%)                                             
   Liver                                              (49)         (50)         (50)                                                
      Angiectasis                                      1 (2%)                    1 (2%)                                             
      Basophilic Focus                                 1 (2%)                    3 (6%)                                             
      Clear Cell Focus                                 1 (2%)                                                                       
      Degeneration, Fatty                                           1 (2%)                                                          
      Eosinophilic Focus                               3 (6%)       6 (12%)      3 (6%)                                             
      Hematopoietic Cell Proliferation                 4 (8%)                    4 (8%)                                             
      Inflammation, Chronic                            2 (4%)       4 (8%)       1 (2%)                                             
      Necrosis                                         7 (14%)      3 (6%)       3 (6%)                                             
      Pigmentation                                     2 (4%)       2 (4%)       1 (2%)                                             
      Vacuolization Cytoplasmic, Focal                 1 (2%)                                                                       
      Bile Duct, Cyst                                  1 (2%)       2 (4%)                                                          
      Bile Duct, Hyperplasia                           1 (2%)                    1 (2%)                                             
      Centrilobular, Degeneration                      1 (2%)                                                                       
      Centrilobular, Necrosis                          1 (2%)       1 (2%)                                                          
      Hepatocyte, Atrophy                              1 (2%)                                                                       
   Mesentery                                          (13)         (5)          (10)                                                
      Artery, Inflammation                             1 (8%)                                                                       
      Fat, Inflammation, Chronic                       1 (8%)                                                                       
      Fat, Necrosis                                    9 (69%)      2 (40%)      4 (40%)                                            
      Lymphatic, Angiectasis                                                     1 (10%)                                            
   Pancreas                                           (48)         (48)         (49)                                                
      Atrophy                                          5 (10%)      1 (2%)       3 (6%)                                             
      Basophilic Focus                                                           5 (10%)                                            
      Inflammation                                     2 (4%)                    1 (2%)                                             
      Duct, Cyst                                       2 (4%)       1 (2%)       2 (4%)                                             
   Stomach, Forestomach                               (48)         (50)         (49)                                                
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    2                                                              
NTP Experiment-Test: 88034-06         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: 22:21:59  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        CONTROL      0.5 PPM      1.0 PPM                                                
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Inflammation, Suppurative                        2 (4%)       3 (6%)       3 (6%)                                             
      Necrosis                                         1 (2%)       1 (2%)       1 (2%)                                             
      Epithelium, Hyperplasia                          3 (6%)       2 (4%)       6 (12%)                                            
   Stomach, Glandular                                 (48)         (49)         (48)                                                
      Inflammation, Acute                                           1 (2%)                                                          
      Mineralization                                                             1 (2%)                                             
      Necrosis                                         1 (2%)       1 (2%)                                                          
      Epithelium, Hyperplasia                                                    1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Heart                                              (50)         (50)         (50)                                                
      Cardiomyopathy                                  37 (74%)     38 (76%)     36 (72%)                                            
      Inflammation, Suppurative                                                  1 (2%)                                             
      Necrosis                                         1 (2%)                                                                       
      Pigmentation, Hemosiderin                                                  1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (48)         (49)         (50)                                                
      Angiectasis                                      1 (2%)                                                                       
      Hyperplasia                                      3 (6%)       2 (4%)       3 (6%)                                             
      Hypertrophy                                      6 (13%)      5 (10%)      6 (12%)                                            
      Capsule, Hyperplasia                                          1 (2%)       2 (4%)                                             
   Adrenal Medulla                                    (48)         (49)         (50)                                                
      Hyperplasia                                      4 (8%)       3 (6%)       4 (8%)                                             
   Islets, Pancreatic                                 (47)         (47)         (48)                                                
      Hyperplasia                                      1 (2%)                                                                       
   Parathyroid Gland                                  (36)         (28)         (29)                                                
      Hyperplasia                                      1 (3%)                                                                       
   Pituitary Gland                                    (48)         (48)         (49)                                                
      Pars Distalis, Hyperplasia                      11 (23%)     14 (29%)     16 (33%)                                            
      Pars Intermedia, Hyperplasia                     1 (2%)       2 (4%)       1 (2%)                                             
      Pars Intermedia, Hypertrophy                                               1 (2%)                                             
   Thyroid Gland                                      (49)         (49)         (50)                                                
      Follicular Cell, Hyperplasia                    22 (45%)     24 (49%)     30 (60%)                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    3                                                              
NTP Experiment-Test: 88034-06         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: 22:21:59  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        CONTROL      0.5 PPM      1.0 PPM                                                
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Clitoral Gland                                     (45)         (44)         (42)                                                
      Inflammation, Chronic Active                     1 (2%)                    2 (5%)                                             
   Ovary                                              (49)         (48)         (50)                                                
      Angiectasis                                      3 (6%)       2 (4%)       1 (2%)                                             
      Atrophy                                         28 (57%)     33 (69%)     30 (60%)                                            
      Cyst                                            23 (47%)     18 (38%)     16 (32%)                                            
      Inflammation, Chronic                            1 (2%)                    1 (2%)                                             
      Necrosis                                                      1 (2%)                                                          
      Germinal Epithelium, Hyperplasia                 2 (4%)       4 (8%)                                                          
      Interstitial Cell, Hyperplasia                                             2 (4%)                                             
   Uterus                                             (49)         (50)         (50)                                                
      Angiectasis                                      4 (8%)       3 (6%)       2 (4%)                                             
      Cyst                                             6 (12%)      2 (4%)       9 (18%)                                            
      Decidual Reaction                                                          1 (2%)                                             
      Hemorrhage                                                    1 (2%)                                                          
      Hydrometra                                       3 (6%)       5 (10%)      1 (2%)                                             
      Inflammation, Chronic                                                      1 (2%)                                             
      Inflammation, Suppurative                                     1 (2%)                                                          
      Thrombosis                                       2 (4%)                                                                       
      Endometrium, Hyperplasia                         1 (2%)       2 (4%)                                                          
      Myometrium, Hyperplasia                          1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (49)         (49)         (50)                                                
      Angiectasis                                      2 (4%)                                                                       
      Hyperplasia                                      3 (6%)       1 (2%)       4 (8%)                                             
   Lymph Node                                         (15)         (6)          (9)                                                 
      Hyperplasia                                      1 (7%)                                                                       
      Iliac, Angiectasis                               2 (13%)                                                                      
      Iliac, Hyperplasia                               1 (7%)                                                                       
      Lumbar, Congestion                               1 (7%)                                                                       
      Lumbar, Hyperplasia                                                        1 (11%)                                            
      Renal, Congestion                                1 (7%)                                                                       
      Renal, Hyperplasia                                                         1 (11%)                                            
   Lymph Node, Bronchial                              (36)         (32)         (33)                                                
      Hyperplasia                                      1 (3%)       1 (3%)       1 (3%)                                             
      Infiltration Cellular, Plasma Cell               1 (3%)                                                                       
      Infiltration Cellular, Histiocyte                1 (3%)                                                                       
   Lymph Node, Mandibular                             (38)         (40)         (41)                                                
      Hematopoietic Cell Proliferation                              1 (3%)                                                          
      Hyperplasia                                      2 (5%)       4 (10%)      3 (7%)                                             
      Necrosis                                         1 (3%)                                                                       
   Lymph Node, Mesenteric                             (45)         (48)         (44)                                                
      Angiectasis                                                                1 (2%)                                             
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    4                                                              
NTP Experiment-Test: 88034-06         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: 22:21:59  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        CONTROL      0.5 PPM      1.0 PPM                                                
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
HEMATOPOIETIC SYSTEM - CONT                                                                                                         
      Congestion                                                    2 (4%)                                                          
      Hematopoietic Cell Proliferation                              1 (2%)       1 (2%)                                             
      Hyperplasia                                      1 (2%)       1 (2%)                                                          
      Infiltration Cellular, Histiocyte                             1 (2%)                                                          
   Lymph Node, Mediastinal                            (43)         (36)         (38)                                                
      Hyperplasia                                      5 (12%)      9 (25%)      1 (3%)                                             
      Infiltration Cellular, Histiocyte                2 (5%)                                                                       
   Spleen                                             (49)         (50)         (50)                                                
      Hematopoietic Cell Proliferation                15 (31%)     19 (38%)     21 (42%)                                            
      Hyperplasia, Histiocytic                                      1 (2%)                                                          
      Hyperplasia, Lymphoid                            6 (12%)      9 (18%)      4 (8%)                                             
      Infiltration Cellular, Histiocyte                             1 (2%)                                                          
   Thymus                                             (35)         (35)         (33)                                                
      Atrophy                                          2 (6%)       3 (9%)       1 (3%)                                             
      Hyperplasia, Lymphoid                            1 (3%)                    2 (6%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (50)         (50)         (50)                                                
      Hyperplasia                                      1 (2%)       1 (2%)       3 (6%)                                             
   Skin                                               (50)         (50)         (50)                                                
      Inflammation, Chronic Active                     1 (2%)                                                                       
      Inflammation, Suppurative                                     1 (2%)                                                          
      Vulva, Inflammation, Suppurative                                           1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (50)         (50)         (50)                                                
      Chondradysplasia                                                           1 (2%)                                             
      Fibrous Osteodystrophy                          15 (30%)     18 (36%)     14 (28%)                                            
      Fracture                                         1 (2%)                                                                       
      Cranium, Fracture                                1 (2%)                                                                       
      Cranium, Myelofibrosis                                        1 (2%)                                                          
      Femur, Myelofibrosis                                          1 (2%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (49)         (49)         (50)                                                
      Angiectasis                                      1 (2%)                                                                       
      Hydrocephalus                                                              1 (2%)                                             
      Meninges, Infiltration Cellular                  2 (4%)       2 (4%)       2 (4%)                                             
   Peripheral Nerve                                   (1)                                                                           
      Degeneration                                     1 (100%)                                                                     
   Spinal Cord                                        (1)                                                                           
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    5                                                              
NTP Experiment-Test: 88034-06         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: 22:21:59  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        CONTROL      0.5 PPM      1.0 PPM                                                
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
NERVOUS SYSTEM - CONT                                                                                                               
      Degeneration                                     1 (100%)                                                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Larynx                                             (50)         (49)         (50)                                                
      Hyperplasia                                     13 (26%)     11 (22%)     24 (48%)                                            
      Inflammation, Chronic Active                     4 (8%)                                                                       
      Inflammation, Suppurative                        5 (10%)      4 (8%)      10 (20%)                                            
      Necrosis                                                                   2 (4%)                                             
      Epiglottis, Hyperplasia                                                    4 (8%)                                             
      Epiglottis, Metaplasia, Squamous                 2 (4%)       2 (4%)      19 (38%)                                            
   Lung                                               (50)         (49)         (50)                                                
      Congestion, Chronic                                                        2 (4%)                                             
      Hemorrhage                                       1 (2%)       2 (4%)       1 (2%)                                             
      Inflammation, Chronic, Focal                     1 (2%)                                                                       
      Alveolar Epithelium, Hyperplasia                 3 (6%)       1 (2%)       3 (6%)                                             
      Alveolar Epithelium, Metaplasia                              43 (88%)     50 (100%)                                           
      Alveolus, Infiltration Cellular, Histiocyte      5 (10%)     39 (80%)     45 (90%)                                            
      Mediastinum, Angiectasis                                      1 (2%)                                                          
      Mediastinum, Necrosis                                                      1 (2%)                                             
      Perivascular, Infiltration Cellular              6 (12%)                   1 (2%)                                             
   Nose                                               (50)         (49)         (50)                                                
      Artery, Inflammation                                          1 (2%)                                                          
      Lateral Wall, Degeneration, Hyaline                          49 (100%)    50 (100%)                                           
      Lateral Wall, Fibrosis                           1 (2%)      23 (47%)     48 (96%)                                            
      Lateral Wall, Hyperplasia                        1 (2%)      42 (86%)     47 (94%)                                            
      Lateral Wall, Inflammation, Suppurative          3 (6%)      44 (90%)     50 (100%)                                           
      Lateral Wall, Metaplasia, Squamous               2 (4%)       3 (6%)      28 (56%)                                            
      Lateral Wall, Necrosis                                                     1 (2%)                                             
      Nasolacrimal Duct, Inflammation, Suppurative     2 (4%)       1 (2%)                                                          
      Olfactory Epithelium, Atrophy                    9 (18%)     23 (47%)     40 (80%)                                            
      Turbinate, Hyperplasia                           1 (2%)                                                                       
      Turbinate, Inflammation, Suppurative             1 (2%)                                                                       
   Trachea                                            (48)         (48)         (50)                                                
      Metaplasia, Squamous                                                       1 (2%)                                             
      Mineralization                                                             1 (2%)                                             
      Necrosis                                                                   1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Ear                                                             (1)                                                              
      Inflammation, Granulomatous                                   1 (100%)                                                        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    6                                                              
NTP Experiment-Test: 88034-06         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: 22:21:59  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        CONTROL      0.5 PPM      1.0 PPM                                                
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (49)         (49)         (50)                                                
      Fibrosis, Focal                                  1 (2%)                                                                       
      Glomerulosclerosis                                                         2 (4%)                                             
      Hydronephrosis                                   1 (2%)                    2 (4%)                                             
      Infarct                                                       1 (2%)                                                          
      Karyomegaly                                                                2 (4%)                                             
      Metaplasia, Osseous                              4 (8%)       1 (2%)       5 (10%)                                            
      Mineralization                                                             1 (2%)                                             
      Nephropathy                                     24 (49%)     27 (55%)     30 (60%)                                            
      Cortex, Inflammation, Suppurative                                          1 (2%)                                             
      Pelvis, Dilatation                                            1 (2%)                                                          
      Renal Tubule, Hyperplasia                                     2 (4%)                                                          
   Urinary Bladder                                    (47)         (48)         (46)                                                
      Inflammation, Suppurative                        1 (2%)                                                                       
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    7                                                              
NTP Experiment-Test: 88034-06         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: 22:21:59  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          CONTROL      0.5 PPM      1.0 PPM                                                
                                                                                                                                    
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially In Study                          50           50           50                                                  
  Early Deaths                                                                                                                      
    Natural Death                                     10            9           15                                                  
    Moribund Sacrifice                                26           30           23                                                  
  Survivors                                                                                                                         
    Terminal Sacrifice                                14           11           12                                                  
  Animals Examined Microscopically                    50           50           50                                                  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Gallbladder                                        (43)         (44)         (40)                                                
      Inflammation, Suppurative                                     1 (2%)       2 (5%)                                             
      Mineralization                                                             1 (3%)                                             
      Epithelium, Hyperplasia                                       1 (2%)                                                          
   Intestine Small, Duodenum                          (44)         (45)         (38)                                                
      Necrosis                                         1 (2%)                                                                       
   Intestine Small, Jejunum                           (43)         (44)         (41)                                                
      Peyer's Patch, Hyperplasia                                                 2 (5%)                                             
   Liver                                              (49)         (50)         (50)                                                
      Angiectasis                                                                1 (2%)                                             
      Basophilic Focus                                 2 (4%)       1 (2%)       2 (4%)                                             
      Clear Cell Focus                                 1 (2%)                                                                       
      Degeneration, Fatty                              2 (4%)       1 (2%)       2 (4%)                                             
      Eosinophilic Focus                              10 (20%)      9 (18%)      3 (6%)                                             
      Hematopoietic Cell Proliferation                 2 (4%)       1 (2%)       1 (2%)                                             
      Hepatodiaphragmatic Nodule                       1 (2%)                    1 (2%)                                             
      Infiltration Cellular, Mast Cell                                           1 (2%)                                             
      Inflammation, Chronic                            2 (4%)       1 (2%)       1 (2%)                                             
      Necrosis                                         3 (6%)       8 (16%)      3 (6%)                                             
      Bile Duct, Cyst                                  1 (2%)       1 (2%)       2 (4%)                                             
      Centrilobular, Necrosis                                       1 (2%)       1 (2%)                                             
   Mesentery                                          (3)          (3)          (4)                                                 
      Artery, Inflammation, Chronic Active                                       1 (25%)                                            
      Fat, Necrosis                                    1 (33%)      1 (33%)      2 (50%)                                            
   Pancreas                                           (49)         (49)         (49)                                                
      Atrophy                                          3 (6%)       3 (6%)       1 (2%)                                             
      Basophilic Focus                                 1 (2%)                                                                       
      Cytoplasmic Alteration                                                     1 (2%)                                             
      Vacuolization Cytoplasmic                        1 (2%)                                                                       
      Duct, Cyst                                                    1 (2%)                                                          
   Stomach, Forestomach                               (49)         (49)         (50)                                                
      Angiectasis                                                                1 (2%)                                             
      Infiltration Cellular, Mast Cell                                           1 (2%)                                             
      Inflammation, Suppurative                                     2 (4%)                                                          
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    8                                                              
NTP Experiment-Test: 88034-06         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: 22:21:59  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          CONTROL      0.5 PPM      1.0 PPM                                                
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Necrosis                                                                   3 (6%)                                             
      Epithelium, Hyperplasia                          1 (2%)       4 (8%)       3 (6%)                                             
   Stomach, Glandular                                 (49)         (47)         (48)                                                
      Inflammation, Acute                              1 (2%)       1 (2%)                                                          
      Mineralization                                                1 (2%)                                                          
      Necrosis                                         2 (4%)       3 (6%)       1 (2%)                                             
      Epithelium, Hyperplasia                          1 (2%)                    1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Blood Vessel                                                                 (1)                                                 
      Mineralization                                                             1 (100%)                                           
   Heart                                              (50)         (50)         (50)                                                
      Cardiomyopathy                                  40 (80%)     40 (80%)     40 (80%)                                            
      Inflammation, Suppurative                        2 (4%)                                                                       
      Mineralization                                                1 (2%)                                                          
      Necrosis                                         1 (2%)                    1 (2%)                                             
      Artery, Inflammation, Chronic Active                                       1 (2%)                                             
      Atrium, Thrombosis                               2 (4%)       1 (2%)       2 (4%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (47)         (49)         (49)                                                
      Hyperplasia                                      9 (19%)     13 (27%)      8 (16%)                                            
      Hypertrophy                                     20 (43%)     16 (33%)     13 (27%)                                            
      Capsule, Hyperplasia                             9 (19%)     12 (24%)      7 (14%)                                            
   Adrenal Medulla                                    (48)         (48)         (49)                                                
      Hyperplasia                                      2 (4%)       2 (4%)                                                          
      Thrombosis                                                    1 (2%)                                                          
   Islets, Pancreatic                                 (49)         (49)         (49)                                                
      Hyperplasia                                      4 (8%)       1 (2%)       2 (4%)                                             
   Pituitary Gland                                    (47)         (49)         (48)                                                
      Pars Distalis, Hyperplasia                       1 (2%)       4 (8%)       3 (6%)                                             
      Pars Intermedia, Hyperplasia                     1 (2%)                    2 (4%)                                             
   Thyroid Gland                                      (49)         (48)         (50)                                                
      Follicular Cell, Hyperplasia                    18 (37%)     20 (42%)     32 (64%)                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    9                                                              
NTP Experiment-Test: 88034-06         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: 22:21:59  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          CONTROL      0.5 PPM      1.0 PPM                                                
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Epididymis                                         (49)         (49)         (50)                                                
      Atrophy                                                       1 (2%)                                                          
      Granuloma Sperm                                  1 (2%)       1 (2%)                                                          
      Inflammation                                     2 (4%)                    1 (2%)                                             
      Inflammation, Chronic                                         1 (2%)                                                          
   Penis                                              (4)          (2)          (7)                                                 
      Inflammation, Suppurative                        3 (75%)      2 (100%)     5 (71%)                                            
   Preputial Gland                                    (49)         (49)         (49)                                                
      Cyst                                            11 (22%)     11 (22%)      8 (16%)                                            
      Hyperplasia                                                                1 (2%)                                             
      Inflammation, Chronic Active                    15 (31%)     13 (27%)      9 (18%)                                            
   Prostate                                           (48)         (47)         (47)                                                
      Hyperplasia                                      1 (2%)                                                                       
      Inflammation, Suppurative                        3 (6%)       5 (11%)      3 (6%)                                             
      Artery, Inflammation, Chronic Active                                       1 (2%)                                             
   Seminal Vesicle                                    (48)         (49)         (49)                                                
      Hyperplasia                                                                1 (2%)                                             
      Inflammation, Suppurative                        1 (2%)                    1 (2%)                                             
   Testes                                             (50)         (49)         (50)                                                
      Atrophy                                         11 (22%)     10 (20%)      5 (10%)                                            
      Mineralization                                                1 (2%)       1 (2%)                                             
      Interstitial Cell, Hyperplasia                   2 (4%)       1 (2%)                                                          
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 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (49)         (49)         (50)                                                
      Hyperplasia                                      3 (6%)       5 (10%)      4 (8%)                                             
      Hyperplasia, Megakaryocyte                                                 1 (2%)                                             
      Infiltration Cellular, Mast Cell                                           1 (2%)                                             
      Necrosis                                         1 (2%)                                                                       
   Lymph Node                                         (2)          (3)          (7)                                                 
      Congestion                                                                 1 (14%)                                            
      Iliac, Hyperplasia                                                         2 (29%)                                            
      Iliac, Infiltration Cellular, Plasma Cell        1 (50%)                                                                      
      Iliac, Pigmentation                                           1 (33%)                                                         
      Renal, Hyperplasia                                                         2 (29%)                                            
   Lymph Node, Bronchial                              (26)         (27)         (32)                                                
      Hyperplasia                                                   1 (4%)       2 (6%)                                             
   Lymph Node, Mandibular                             (34)         (31)         (32)                                                
      Hyperplasia                                      1 (3%)       1 (3%)                                                          
      Infiltration Cellular, Mast Cell                                           1 (3%)                                             
   Lymph Node, Mesenteric                             (48)         (46)         (44)                                                
      Angiectasis                                      3 (6%)                    4 (9%)                                             
      Congestion                                       1 (2%)       2 (4%)                                                          
      Hematopoietic Cell Proliferation                 2 (4%)                                                                       
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   10                                                              
NTP Experiment-Test: 88034-06         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: 22:21:59  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          CONTROL      0.5 PPM      1.0 PPM                                                
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
HEMATOPOIETIC SYSTEM - CONT                                                                                                         
      Hemorrhage                                                    1 (2%)                                                          
      Hyperplasia                                      2 (4%)       2 (4%)       3 (7%)                                             
   Lymph Node, Mediastinal                            (37)         (39)         (43)                                                
      Hyperplasia                                      1 (3%)       5 (13%)      5 (12%)                                            
   Spleen                                             (49)         (49)         (50)                                                
      Angiectasis                                      1 (2%)                    1 (2%)                                             
      Hematopoietic Cell Proliferation                14 (29%)     14 (29%)     15 (30%)                                            
      Hyperplasia, Lymphoid                            2 (4%)       2 (4%)       1 (2%)                                             
      Infiltration Cellular, Mast Cell                                           1 (2%)                                             
      Pigmentation, Melanin                            1 (2%)                                                                       
   Thymus                                             (29)         (26)         (25)                                                
      Atrophy                                          4 (14%)      1 (4%)       5 (20%)                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Skin                                               (49)         (50)         (50)                                                
      Inflammation, Chronic Active                     1 (2%)       1 (2%)                                                          
      Epidermis, Hyperplasia                                        2 (4%)                                                          
      Prepuce, Inflammation, Chronic Active           11 (22%)     13 (26%)     16 (32%)                                            
      Subcutaneous Tissue, Edema                                    1 (2%)                                                          
      Subcutaneous Tissue, Hemorrhage                  1 (2%)                                                                       
      Subcutaneous Tissue, Infiltration Cellular,                                                                                   
           Mast Cell                                                1 (2%)                                                          
      Subcutaneous Tissue, Inflammation, Chronic                    1 (2%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (50)         (50)         (50)                                                
      Fibrous Osteodystrophy                           1 (2%)       2 (4%)       1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (49)         (49)         (50)                                                
      Developmental Malformation                       1 (2%)                                                                       
      Hemorrhage                                       1 (2%)                                                                       
      Hydrocephalus                                                              1 (2%)                                             
      Artery, Inflammation, Chronic Active                                       1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   11                                                              
NTP Experiment-Test: 88034-06         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: 22:21:59  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          CONTROL      0.5 PPM      1.0 PPM                                                
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Larynx                                             (49)         (49)         (50)                                                
      Hyperplasia                                      4 (8%)       7 (14%)     15 (30%)                                            
      Inflammation, Acute                              1 (2%)                                                                       
      Inflammation, Chronic                            1 (2%)                                                                       
      Inflammation, Chronic Active                     6 (12%)      7 (14%)      7 (14%)                                            
      Inflammation, Suppurative                        1 (2%)       5 (10%)      4 (8%)                                             
      Epiglottis, Hyperplasia                          1 (2%)       2 (4%)       2 (4%)                                             
      Epiglottis, Metaplasia, Squamous                 2 (4%)       1 (2%)      10 (20%)                                            
   Lung                                               (49)         (49)         (50)                                                
      Angiectasis                                      1 (2%)                                                                       
      Hemorrhage                                       1 (2%)                                                                       
      Inflammation, Chronic, Focal                                  1 (2%)                                                          
      Alveolar Epithelium, Hyperplasia                10 (20%)      8 (16%)      1 (2%)                                             
      Alveolar Epithelium, Metaplasia                              48 (98%)     47 (94%)                                            
      Alveolus, Infiltration Cellular, Histiocyte      3 (6%)      40 (82%)     41 (82%)                                            
      Bronchiole, Metaplasia                                                     1 (2%)                                             
      Bronchiole, Necrosis                                                       1 (2%)                                             
      Perivascular, Infiltration Cellular              1 (2%)                    3 (6%)                                             
   Nose                                               (49)         (48)         (49)                                                
      Lateral Wall, Degeneration, Hyaline              2 (4%)      48 (100%)    49 (100%)                                           
      Lateral Wall, Fibrosis                                        8 (17%)     43 (88%)                                            
      Lateral Wall, Hyperplasia                        2 (4%)      33 (69%)     45 (92%)                                            
      Lateral Wall, Inflammation, Suppurative          1 (2%)      38 (79%)     46 (94%)                                            
      Lateral Wall, Metaplasia, Squamous               1 (2%)       2 (4%)      20 (41%)                                            
      Nasolacrimal Duct, Inflammation, Suppurative     2 (4%)       2 (4%)       2 (4%)                                             
      Olfactory Epithelium, Atrophy                    4 (8%)       4 (8%)      18 (37%)                                            
   Trachea                                            (49)         (49)         (49)                                                
      Hyperplasia                                      1 (2%)                                                                       
      Metaplasia, Squamous                                                       1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                (3)          (1)          (1)                                                 
      Inflammation                                     2 (67%)      1 (100%)     1 (100%)                                           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (49)         (49)         (50)                                                
      Cyst                                             4 (8%)       1 (2%)       3 (6%)                                             
      Hydronephrosis                                                1 (2%)                                                          
      Infarct                                          1 (2%)                    1 (2%)                                             
      Mineralization                                                2 (4%)                                                          
      Nephropathy                                     40 (82%)     43 (88%)     37 (74%)                                            
      Cortex, Inflammation, Suppurative                             2 (4%)       3 (6%)                                             
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   12                                                              
NTP Experiment-Test: 88034-06         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: 22:21:59  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          CONTROL      0.5 PPM      1.0 PPM                                                
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
URINARY SYSTEM - CONT                                                                                                               
      Papilla, Inflammation, Suppurative               3 (6%)       6 (12%)      6 (12%)                                            
      Papilla, Necrosis                                1 (2%)                                                                       
      Pelvis, Dilatation                               2 (4%)                    1 (2%)                                             
      Renal Tubule, Hyperplasia                        1 (2%)                                                                       
   Urinary Bladder                                    (47)         (49)         (48)                                                
      Calculus Gross Observation                                    3 (6%)                                                          
      Inflammation, Chronic Active                     2 (4%)       1 (2%)       2 (4%)                                             
      Inflammation, Suppurative                        1 (2%)       5 (10%)      5 (10%)                                            
      Transitional Epithelium, Hyperplasia                                       1 (2%)                                             
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   13                                                              
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