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TDMS Study 88004-05 Pathology Tables

NTP Experiment-Test: 88004-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT18
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 12/17/03
Route: RESPIRATORY EXPOSURE WHOLE BODY                          DIVINYLBENZENE                                    Time: 12:01:01

                                                         FINAL #1 RATS




       Facility:  Battelle Northwest

       Chemical CAS #:  1321-74-0

       Lock Date:  04/16/02

       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
b  Average severity grade (1-minimal;2-mild;3-moderate;4-marked)

                                                              Page   1


NTP Experiment-Test: 88004-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT18  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 12/17/03    
Route: RESPIRATORY EXPOSURE WHOLE BODY                          DIVINYLBENZENE                                    Time: 12:01:01    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS FEMALE                      CONTROL      100 PPM      200 PPM      400 PPM                                
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
DISPOSITION SUMMARY                                                                                                                 
                                                                                                                                    
  Animals Initially In Study                          50           50           50           50                                     
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                10           16           14           26                                     
    Natural Death                                      7            3            3            2                                     
    Accidently Killed                                               1                                                               
  Survivors                                                                                                                         
    Terminal Sacrifice                                33           30           33           22                                     
                                                                                                                                    
  Animals Examined Microscopically                    50           50           50           50                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Intestine Large, Colon                             (50)         (49)         (49)         (50)                                   
      Epithelium, Metaplasia, Focal, Squamous                       1 [3.0]                                                         
   Liver                                              (50)         (50)         (50)         (50)                                   
      Clear Cell Focus                                 5 [2.0]      7 [2.4]      6 [2.8]                                            
      Hepatodiaphragmatic Nodule                       5 [4.0]      7 [4.0]      6 [3.5]      9 [4.0]                               
      Necrosis                                                                   1 [3.0]                                            
      Vacuolization Cytoplasmic                        4 [2.0]      3 [3.0]                   3 [2.0]                               
      Bile Duct, Hyperplasia                                                     1 [4.0]                                            
      Hepatocyte, Regeneration                                      1 [4.0]      1 [4.0]                                            
      Periportal, Inflammation, Chronic                3 [2.3]      2 [3.0]      1 [2.0]      2 [1.5]                               
      Portal, Bile Stasis                              1 [3.0]      3 [3.7]      2 [3.5]      1 [3.0]                               
      Serosa, Fibrosis                                                           1 [3.0]                                            
   Mesentery                                          (15)         (20)         (17)         (6)                                    
      Necrosis                                        14 [3.0]     20 [3.0]     16 [3.1]      6 [3.0]                               
   Oral Mucosa                                        (1)                                                                           
      Pharyngeal, Ulcer                                1 [4.0]                                                                      
   Pancreas                                           (50)         (49)         (50)         (50)                                   
      Acinus, Atrophy                                  3 [1.7]      5 [1.2]      2 [1.0]      4 [2.8]                               
   Salivary Glands                                    (50)         (50)         (50)         (50)                                   
      Inflammation, Chronic                                         1 [3.0]                                                         
   Stomach, Forestomach                               (50)         (50)         (49)         (49)                                   
      Hyperplasia, Focal, Squamous                                  1 [4.0]      1 [3.0]                                            
      Ulcer                                            1 [4.0]      1 [3.0]      1 [4.0]      1 [4.0]                               
   Stomach, Glandular                                 (50)         (50)         (49)         (49)                                   
      Erosion                                                                    1 [2.0]      1 [2.0]                               
      Ulcer                                                                      1 [4.0]                                            
      Epithelium, Hyperplasia                          1 [2.0]                                                                      
   Tongue                                             (1)          (1)          (3)          (3)                                    
      Epithelium, Hyperplasia                          1 [4.0]                   3 [2.7]      2 [4.0]                               
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Average severity grade (1-minimal;2-mild;3-moderate;4-marked)                                                                    
                                                                                                                                    
                                                             Page    2                                                              
                                                                                                                                   
NTP Experiment-Test: 88004-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT18  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 12/17/03    
Route: RESPIRATORY EXPOSURE WHOLE BODY                          DIVINYLBENZENE                                    Time: 12:01:01    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS FEMALE                      CONTROL      100 PPM      200 PPM      400 PPM                                
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
   Tooth                                                                        (1)                                                 
      Peridontal Tissue, Inflammation                                            1 [4.0]                                            
      Pulp, Inflammation, Suppurative                                            1 [4.0]                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Heart                                              (50)         (50)         (50)         (50)                                   
      Cardiomyopathy                                                                          3 [1.7]                               
      Atrium, Thrombosis                                            1 [4.0]      2 [4.0]                                            
      Pericardium, Infiltration Cellular, Lymphoid                                            1 [3.0]                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (50)         (50)         (50)         (50)                                   
      Accessory Adrenal Cortical Nodule                                          1 [4.0]                                            
      Hemorrhage                                                    1 [2.0]                                                         
      Hyperplasia                                                                             1 [2.0]                               
      Necrosis                                                      1 [4.0]                                                         
      Vacuolization Cytoplasmic                       14 [1.9]      5 [1.8]      7 [1.6]     12 [1.5]                               
   Adrenal Medulla                                    (50)         (50)         (50)         (50)                                   
      Hyperplasia                                      1 [2.0]      1 [2.0]      5 [2.6]      2 [3.0]                               
   Parathyroid Gland                                  (49)         (49)         (47)         (49)                                   
      Hyperplasia                                                                1 [2.0]                                            
   Pituitary Gland                                    (50)         (50)         (50)         (50)                                   
      Cyst                                             6 [3.5]      6 [2.8]      1 [4.0]      5 [2.8]                               
      Pars Distalis, Angiectasis                       1 [3.0]                                                                      
      Pars Distalis, Hematocyst                                                               1 [4.0]                               
      Pars Distalis, Hyperplasia                       4 [3.0]      8 [2.9]      4 [3.0]      7 [2.3]                               
   Thyroid Gland                                      (50)         (50)         (50)         (50)                                   
      Ultimobranchial Cyst                             1 [2.0]                                                                      
      C-Cell, Hyperplasia                              5 [2.8]      8 [2.0]      6 [1.8]      1 [1.0]                               
      Follicular Cell, Hyperplasia                                  1 [2.0]                   1 [2.0]                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Average severity grade (1-minimal;2-mild;3-moderate;4-marked)                                                                    
                                                                                                                                    
                                                             Page    3                                                              
                                                                                                                                   
NTP Experiment-Test: 88004-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT18  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 12/17/03    
Route: RESPIRATORY EXPOSURE WHOLE BODY                          DIVINYLBENZENE                                    Time: 12:01:01    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS FEMALE                      CONTROL      100 PPM      200 PPM      400 PPM                                
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
GENITAL SYSTEM - CONT                                                                                                               
   Clitoral Gland                                     (50)         (50)         (50)         (50)                                   
      Cyst                                             3 [3.7]                   1 [4.0]                                            
      Hyperplasia                                      1 [3.0]      3 [4.0]      2 [2.5]      2 [4.0]                               
      Inflammation, Chronic                            2 [3.5]      1 [2.0]      1 [3.0]                                            
   Ovary                                              (50)         (50)         (50)         (50)                                   
      Cyst                                             5 [3.6]      6 [2.7]     11 [3.2]      4 [2.8]                               
      Bilateral, Cyst                                  1 [3.0]                                                                      
   Uterus                                             (50)         (50)         (50)         (50)                                   
      Hemorrhage                                                                 1 [4.0]                                            
      Necrosis                                                      1 [4.0]                                                         
      Endometrium, Hyperplasia                         2 [2.5]      1 [2.0]      1 [3.0]      2 [1.5]                               
      Myometrium, Hyperplasia                                                    1 [3.0]                                            
   Vagina                                                          (2)                       (3)                                    
      Inflammation, Suppurative                                     1 [4.0]                                                         
      Muscularis, Hypertrophy                                                                 1 [4.0]                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (50)         (50)         (50)         (50)                                   
      Myelofibrosis                                                              1 [3.0]                                            
   Lymph Node                                         (6)          (10)         (9)          (8)                                    
      Deep Cervical, Infiltration Cellular,                                                                                         
        Histiocyte                                                  3 [3.3]                   1 [2.0]                               
      Pancreatic, Pigmentation                                      1 [4.0]      1 [4.0]                                            
   Lymph Node, Bronchial                              (8)          (9)          (5)          (14)                                   
      Infiltration Cellular, Histiocyte                                                       1 [3.0]                               
   Lymph Node, Mesenteric                             (50)         (50)         (50)         (50)                                   
      Infiltration Cellular, Histiocyte                2 [2.5]      1 [3.0]      2 [3.5]                                            
      Pigmentation                                                                            1 [4.0]                               
   Lymph Node, Mediastinal                            (32)         (37)         (44)         (34)                                   
      Fibrosis                                                                   1 [3.0]                                            
      Hyperplasia, Lymphoid                            1 [4.0]                   1 [3.0]                                            
      Infiltration Cellular, Histiocyte                2 [3.0]      1 [3.0]                                                         
      Inflammation, Suppurative                        1 [3.0]                                                                      
   Spleen                                             (50)         (50)         (50)         (50)                                   
      Accessory Spleen                                 2            1            1                                                  
      Fibrosis                                         3 [3.0]      1 [4.0]      3 [3.3]      1 [2.0]                               
      Hematopoietic Cell Proliferation                              1 [4.0]                                                         
      Hemorrhage                                       2 [3.5]      1 [4.0]      1 [4.0]      2 [4.0]                               
      Hyperplasia, Focal, Lymphoid                                  2 [3.5]                                                         
      Inflammation, Chronic Active                                               1 [3.0]                                            
      Necrosis                                                                                1 [4.0]                               
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Average severity grade (1-minimal;2-mild;3-moderate;4-marked)                                                                    
                                                                                                                                    
                                                             Page    4                                                              
                                                                                                                                   
NTP Experiment-Test: 88004-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT18  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 12/17/03    
Route: RESPIRATORY EXPOSURE WHOLE BODY                          DIVINYLBENZENE                                    Time: 12:01:01    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS FEMALE                      CONTROL      100 PPM      200 PPM      400 PPM                                
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
HEMATOPOIETIC SYSTEM - CONT                                                                                                         
   Thymus                                             (45)         (41)         (46)         (39)                                   
      Cyst                                                                                    1 [4.0]                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (50)         (50)         (50)         (50)                                   
      Galactocele                                      1 [1.0]      2 [2.0]                                                         
      Hyperplasia                                                                1 [3.0]                                            
      Inflammation, Chronic                                                      1 [3.0]                                            
   Skin                                               (50)         (50)         (50)         (50)                                   
      Cyst Epithelial Inclusion                                     2 [4.0]                   1 [4.0]                               
      Hyperkeratosis                                                1 [3.0]                                                         
      Inflammation, Granulomatous                                                             1 [4.0]                               
      Ulcer                                            1 [4.0]                   1 [4.0]                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (50)         (50)         (50)         (50)                                   
      Joint, Fracture                                               1 [4.0]                                                         
      Tibia, Fracture                                                            1 [4.0]                                            
   Skeletal Muscle                                    (2)          (3)          (7)          (5)                                    
      Inflammation, Chronic                                         1 [4.0]                                                         
      Necrosis                                         1 [4.0]      1 [3.0]                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (50)         (50)         (50)         (50)                                   
      Compression                                      9 [3.1]     10 [3.1]     11 [2.9]      7 [3.1]                               
      Congestion                                                    1 [1.0]                                                         
      Hemorrhage                                       2 [1.0]      2 [4.0]      6 [2.8]      3 [3.7]                               
      Infarct                                                                    1 [2.0]                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Larynx                                             (50)         (50)         (49)         (50)                                   
      Foreign Body                                                  1 [4.0]      3 [4.0]                                            
      Inflammation, Suppurative                                     2 [2.0]      1 [2.0]                                            
      Epiglottis, Metaplasia, Squamous                 1 [2.0]                                                                      
   Lung                                               (50)         (50)         (50)         (50)                                   
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Average severity grade (1-minimal;2-mild;3-moderate;4-marked)                                                                    
                                                                                                                                    
                                                             Page    5                                                              
                                                                                                                                   
NTP Experiment-Test: 88004-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT18  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 12/17/03    
Route: RESPIRATORY EXPOSURE WHOLE BODY                          DIVINYLBENZENE                                    Time: 12:01:01    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS FEMALE                      CONTROL      100 PPM      200 PPM      400 PPM                                
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
RESPIRATORY SYSTEM - CONT                                                                                                           
      Atrophy                                          1 [4.0]                                                                      
      Cyst                                                                       1 [4.0]                                            
      Foreign Body                                                               1 [2.0]                                            
      Hemorrhage                                       1 [2.0]      1 [1.0]      1 [2.0]      1 [3.0]                               
      Infiltration Cellular, Histiocyte                1 [4.0]                                                                      
      Inflammation, Chronic                                                      1 [2.0]                                            
      Inflammation, Chronic, Diffuse                   1 [3.0]                                1 [2.0]                               
      Inflammation, Chronic, Focal                    27 [1.3]     22 [1.4]     26 [1.3]     33 [1.2]                               
      Alveolar Epithelium, Hyperplasia                 4 [2.3]      2 [1.5]      3 [1.7]      1 [3.0]                               
      Alveolar Epithelium, Hypertrophy                 1 [1.0]      1 [1.0]                   1 [2.0]                               
      Alveolus, Infiltration Cellular, Focal,                                                                                       
        Histiocyte                                     8 [1.1]      3 [1.3]      6 [1.3]      5 [1.2]                               
      Interstitium, Fibrosis                                                                  1 [1.0]                               
      Mediastinum, Necrosis, Fatty                     1 [4.0]                                                                      
   Nose                                               (50)         (50)         (49)         (49)                                   
      Foreign Body                                     1 [3.0]      5 [2.0]      1 [3.0]                                            
      Inflammation, Suppurative                        5 [2.4]     12 [1.7]      8 [1.3]      7 [1.6]                               
      Ulcer                                            1 [4.0]                                                                      
      Glands, Dilatation                                           17 [1.3]     38 [1.3]     44 [1.7]                               
      Goblet Cell, Hyperplasia                         1 [2.0]      3 [1.7]      1 [1.0]      4 [1.5]                               
      Nasolacrimal Duct, Inflammation, Suppurative     3 [2.0]      1 [3.0]      3 [2.3]      1 [2.0]                               
      Nasopharyngeal Duct, Inflammation,                                                                                            
        Suppurative                                                              1 [3.0]                                            
      Olfactory Epithelium, Degeneration                           50 [1.5]     49 [1.8]     48 [2.0]                               
      Olfactory Epithelium, Degeneration, Hyaline     10 [1.5]     14 [1.1]     15 [1.1]      4 [1.0]                               
      Olfactory Epithelium, Hyperplasia, Basal Cell                25 [1.0]     42 [1.3]     45 [1.8]                               
      Olfactory Epithelium, Regeneration, Focal        1 [1.0]                                                                      
      Respiratory Epithelium, Degeneration, Hyaline    5 [1.8]      3 [2.0]      4 [1.3]                                            
      Respiratory Epithelium, Hyperplasia              1 [2.0]                   1 [3.0]                                            
      Respiratory Epithelium, Metaplasia, Squamous                                            1 [2.0]                               
   Pleura                                             (50)         (50)         (50)         (49)                                   
      Fibrosis                                         1 [2.0]                                                                      
      Infiltration Cellular, Lymphoid                                                         1 [4.0]                               
   Trachea                                            (50)         (50)         (50)         (50)                                   
      Glands, Degeneration, Cystic                                               1 [1.0]      1 [2.0]                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                (50)         (48)         (49)         (49)                                   
      Atrophy                                                                    1 [4.0]                                            
      Inflammation, Chronic                            1 [1.0]                                                                      
      Anterior Chamber, Hemorrhage                                               1 [4.0]                                            
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Average severity grade (1-minimal;2-mild;3-moderate;4-marked)                                                                    
                                                                                                                                    
                                                             Page    6                                                              
                                                                                                                                   
NTP Experiment-Test: 88004-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT18  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 12/17/03    
Route: RESPIRATORY EXPOSURE WHOLE BODY                          DIVINYLBENZENE                                    Time: 12:01:01    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS FEMALE                      CONTROL      100 PPM      200 PPM      400 PPM                                
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
SPECIAL SENSES SYSTEM - CONT                                                                                                        
      Ciliary Body, Inflammation                                    1 [2.0]                                                         
      Cornea, Inflammation                             1 [2.0]                                                                      
      Lens, Cataract                                   1 [4.0]      3 [2.7]      4 [3.8]      1 [4.0]                               
   Harderian Gland                                    (50)         (50)         (50)         (50)                                   
      Inflammation, Suppurative                        1 [4.0]                                                                      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (50)         (50)         (49)         (50)                                   
      Cyst                                                                       1 [4.0]                                            
      Nephropathy, Chronic                            19 [1.4]     21 [1.3]     19 [1.7]     10 [2.2]                               
      Bilateral, Cortex, Renal Tubule, Degeneration                                           1 [4.0]                               
      Cortex, Infarct                                                                         2 [2.0]                               
      Cortex, Renal Tubule, Accumulation, Hyaline                                                                                   
        Droplet                                                                               1 [4.0]                               
      Cortex, Renal Tubule, Hyperplasia                1 [3.0]      1 [1.0]                                                         
      Medulla, Renal Tubule, Degeneration                                                     1 [3.0]                               
      Pelvis, Transitional Epithelium, Hyperplasia     1 [2.0]                                1 [2.0]                               
      Pelvis, Transitional Epithelium,                                                                                              
        Mineralization                                 1 [2.0]                                                                      
      Renal Tubule, Dilatation                         1 [4.0]                                                                      
   Urinary Bladder                                    (50)         (50)         (49)         (49)                                   
      Transitional Epithelium, Hyperplasia             1 [4.0]                                                                      
                                                                                                                                    
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Average severity grade (1-minimal;2-mild;3-moderate;4-marked)                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page    7                                                              
                                                                                                                                   
NTP Experiment-Test: 88004-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT18  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 12/17/03    
Route: RESPIRATORY EXPOSURE WHOLE BODY                          DIVINYLBENZENE                                    Time: 12:01:01    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS MALE                        CONTROL      100 PPM      200 PPM      400 PPM                                
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
DISPOSITION SUMMARY                                                                                                                 
                                                                                                                                    
  Animals Initially In Study                          50           50           50           50                                     
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                15            9           12           13                                     
    Natural Death                                      4            6            6            5                                     
  Survivors                                                                                                                         
    Terminal Sacrifice                                31           35           31           32                                     
    Natural Death                                                                1                                                  
                                                                                                                                    
  Animals Examined Microscopically                    50           50           50           50                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Esophagus                                          (50)         (50)         (50)         (50)                                   
      Foreign Body                                                                            1                                     
   Intestine Small, Jejunum                           (46)         (47)         (47)         (46)                                   
      Necrosis                                                      1 [3.0]                                                         
   Intestine Small, Ileum                             (46)         (47)         (45)         (46)                                   
      Dilatation                                                    1 [4.0]                                                         
   Liver                                              (50)         (49)         (50)         (50)                                   
      Angiectasis                                                                1 [4.0]      1 [3.0]                               
      Clear Cell Focus                                 2 [1.0]      5 [2.5]      1 [4.0]      1 [4.0]                               
      Hemorrhage                                       1 [3.0]                                                                      
      Hepatodiaphragmatic Nodule                       2 [4.0]      2 [4.0]      4 [4.0]      8 [4.0]                               
      Inflammation, Granulomatous                                   1 [3.0]                                                         
      Necrosis                                         1 [4.0]      1 [2.0]      3 [2.3]      2 [3.5]                               
      Vacuolization Cytoplasmic                        1 [3.0]      2 [2.0]      3 [2.7]      3 [2.3]                               
      Bile Duct, Hyperplasia                                                     3 [2.0]                                            
      Hepatocyte, Regeneration                                                   1 [4.0]                                            
      Periportal, Inflammation, Chronic                                          2 [2.0]                                            
      Serosa, Fibrosis                                              1 [4.0]                   1 [4.0]                               
      Serosa, Hemorrhage                                                                      1 [4.0]                               
   Mesentery                                          (12)         (13)         (18)         (11)                                   
      Necrosis                                         7 [2.9]     13 [2.9]     18 [2.9]      9 [3.0]                               
      Fat, Hemorrhage                                                                         1 [4.0]                               
   Oral Mucosa                                        (1)                       (1)          (4)                                    
      Gingival, Cyst                                                                          1 [4.0]                               
      Gingival, Hyperplasia, Squamous                  1 [1.0]                                                                      
   Pancreas                                           (50)         (49)         (50)         (50)                                   
      Thrombosis                                                                 1 [4.0]                                            
      Acinus, Atrophy                                 15 [1.8]     18 [1.8]     27 [1.7]     21 [2.0]                               
      Acinus, Hyperplasia                                                        1 [3.0]                                            
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Average severity grade (1-minimal;2-mild;3-moderate;4-marked)                                                                    
                                                                                                                                    
                                                             Page    8                                                              
                                                                                                                                   
NTP Experiment-Test: 88004-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT18  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 12/17/03    
Route: RESPIRATORY EXPOSURE WHOLE BODY                          DIVINYLBENZENE                                    Time: 12:01:01    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS MALE                        CONTROL      100 PPM      200 PPM      400 PPM                                
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Acinus, Inflammation                                          1 [2.0]                                                         
      Duct, Cyst                                       1 [1.0]      2 [2.5]      3 [3.0]                                            
   Stomach, Forestomach                               (50)         (48)         (50)         (50)                                   
      Diverticulum                                                  1 [3.0]                                                         
      Hyperplasia, Squamous                            1 [2.0]                                                                      
      Inflammation, Suppurative                                     1 [1.0]                                                         
      Ulcer                                            4 [3.0]      1 [4.0]      1 [4.0]                                            
   Stomach, Glandular                                 (50)         (48)         (50)         (49)                                   
      Erosion                                                       2 [2.5]      2 [2.5]      2 [2.5]                               
      Ulcer                                            1 [4.0]      2 [4.0]      1 [3.0]                                            
      Epithelium, Hyperplasia                                                                 1 [2.0]                               
   Tongue                                             (1)          (1)                                                              
      Epithelium, Hyperplasia                                       1 [3.0]                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Blood Vessel                                       (50)         (50)         (50)         (50)                                   
      Thrombosis                                       1 [3.0]                                                                      
   Heart                                              (50)         (50)         (50)         (50)                                   
      Cardiomyopathy                                   7 [1.6]      5 [2.2]      1 [2.0]      1 [2.0]                               
      Atrium, Thrombosis                               2 [3.5]      1 [4.0]      2 [4.0]      1 [4.0]                               
      Pericardium, Inflammation                                                  1 [3.0]                                            
      Pericardium, Pigmentation                                                  1 [4.0]                                            
      Pericardium, Epicardium, Infiltration                                                                                         
        Cellular, Histiocyte                                        1 [4.0]                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (50)         (50)         (50)         (50)                                   
      Hyperplasia                                      1 [3.0]                                2 [1.5]                               
      Necrosis                                                      2 [2.5]                                                         
      Vacuolization Cytoplasmic                        8 [2.1]      8 [1.8]      7 [1.7]      6 [1.8]                               
   Adrenal Medulla                                    (50)         (50)         (50)         (50)                                   
      Hyperplasia                                     12 [3.2]     13 [2.7]      8 [2.4]     14 [2.3]                               
      Bilateral, Hyperplasia                                                                  1 [4.0]                               
   Islets, Pancreatic                                 (50)         (48)         (50)         (50)                                   
      Hyperplasia                                      1 [1.0]      1 [1.0]      2 [2.0]      2 [3.0]                               
   Parathyroid Gland                                  (46)         (48)         (49)         (47)                                   
      Hyperplasia                                      1 [2.0]      1 [3.0]                                                         
   Pituitary Gland                                    (50)         (50)         (50)         (49)                                   
      Cyst                                             1 [2.0]      1 [4.0]      1 [4.0]      1 [3.0]                               
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Average severity grade (1-minimal;2-mild;3-moderate;4-marked)                                                                    
                                                                                                                                    
                                                             Page    9                                                              
                                                                                                                                   
NTP Experiment-Test: 88004-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT18  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 12/17/03    
Route: RESPIRATORY EXPOSURE WHOLE BODY                          DIVINYLBENZENE                                    Time: 12:01:01    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS MALE                        CONTROL      100 PPM      200 PPM      400 PPM                                
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ENDOCRINE SYSTEM - CONT                                                                                                             
      Hemorrhage                                       1 [3.0]                                1 [3.0]                               
      Pars Distalis, Hematocyst                                     1 [4.0]                                                         
      Pars Distalis, Hyperplasia                       5 [2.2]      8 [2.3]      9 [2.6]      8 [2.8]                               
   Thyroid Gland                                      (50)         (50)         (50)         (49)                                   
      C-Cell, Hyperplasia                              2 [2.5]      4 [3.0]      9 [2.6]      7 [2.4]                               
      Follicular Cell, Hyperplasia                                  2 [2.0]      2 [2.5]      1 [1.0]                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Penis                                                                        (2)                                                 
      Inflammation                                                               1 [4.0]                                            
   Preputial Gland                                    (48)         (50)         (50)         (49)                                   
      Cyst                                             1 [3.0]      1 [4.0]      2 [4.0]      1 [4.0]                               
      Hyperplasia                                      1 [4.0]      4 [3.8]      1 [4.0]      1 [4.0]                               
   Prostate                                           (50)         (50)         (50)         (50)                                   
      Hyperplasia                                                                1 [1.0]                                            
      Inflammation, Suppurative                        5 [2.0]      1 [2.0]      4 [3.5]      2 [1.5]                               
   Seminal Vesicle                                    (50)         (49)         (50)         (50)                                   
      Dilatation                                                                              1 [4.0]                               
      Hyperplasia                                                   1 [3.0]                                                         
      Inflammation, Suppurative                        1 [3.0]                                                                      
   Testes                                             (50)         (50)         (50)         (50)                                   
      Artery, Inflammation, Chronic Active                                       2 [3.0]                                            
      Germinal Epithelium, Atrophy                    16 [3.9]     12 [3.1]     11 [3.3]      9 [3.4]                               
      Interstitial Cell, Hyperplasia                   7 [3.0]      6 [2.8]      2 [2.5]      3 [2.7]                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Lymph Node                                         (11)         (5)          (11)         (6)                                    
      Deep Cervical, Angiectasis                       1 [4.0]                                1 [2.0]                               
      Deep Cervical, Cyst                                           1 [2.0]                                                         
      Deep Cervical, Hemorrhage                                                  1 [3.0]                                            
      Deep Cervical, Hyperplasia, Lymphoid             1 [3.0]                                                                      
      Pancreatic, Ectasia                                                        1 [3.0]                                            
      Pancreatic, Hemorrhage                                                                  1 [3.0]                               
      Pancreatic, Infiltration Cellular, Histiocyte                              1 [3.0]                                            
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Average severity grade (1-minimal;2-mild;3-moderate;4-marked)                                                                    
                                                                                                                                    
                                                             Page   10                                                              
                                                                                                                                   
NTP Experiment-Test: 88004-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT18  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 12/17/03    
Route: RESPIRATORY EXPOSURE WHOLE BODY                          DIVINYLBENZENE                                    Time: 12:01:01    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS MALE                        CONTROL      100 PPM      200 PPM      400 PPM                                
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
HEMATOPOIETIC SYSTEM - CONT                                                                                                         
   Lymph Node, Bronchial                              (7)          (6)          (12)         (5)                                    
      Hemorrhage                                                                              1 [3.0]                               
      Infiltration Cellular                                                                   1 [3.0]                               
      Pigmentation                                                                            1 [3.0]                               
   Lymph Node, Mesenteric                             (49)         (49)         (50)         (50)                                   
      Angiectasis                                      1 [4.0]                                                                      
      Ectasia                                                       1 [4.0]                                                         
      Hemorrhage                                                                              1 [3.0]                               
      Hyperplasia, Lymphoid                                                      1 [4.0]                                            
      Infiltration Cellular, Histiocyte                1 [1.0]                   1 [4.0]      3 [3.3]                               
   Lymph Node, Mediastinal                            (19)         (23)         (25)         (38)                                   
      Angiectasis                                                                             1 [4.0]                               
      Hyperplasia, Lymphoid                                                                   1 [3.0]                               
   Spleen                                             (50)         (49)         (50)         (50)                                   
      Accessory Spleen                                              3                         1                                     
      Fibrosis                                         2 [3.5]      6 [3.2]      4 [3.3]      1 [4.0]                               
      Hematopoietic Cell Proliferation                                                        1 [4.0]                               
      Hemorrhage                                                    2 [4.0]      1 [4.0]      1 [4.0]                               
      Hyperplasia, Focal, Lymphoid                                  1 [3.0]                                                         
      Necrosis                                         3 [4.0]      1 [4.0]      1 [4.0]      1 [4.0]                               
      Lymphocyte, Hyperplasia, Diffuse                 1 [2.0]                                                                      
   Thymus                                             (48)         (44)         (46)         (42)                                   
      Hemorrhage                                                                 1 [3.0]                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (35)         (43)         (47)         (48)                                   
      Galactocele                                      3 [3.7]      2 [1.5]      6 [4.0]      3 [4.0]                               
   Skin                                               (50)         (50)         (50)         (50)                                   
      Cyst Epithelial Inclusion                        4 [4.0]      1 [4.0]      3 [4.0]      2 [4.0]                               
      Hyperkeratosis                                   2 [3.5]      1 [3.0]      2 [3.5]                                            
      Inflammation, Acute                                                        2 [4.0]                                            
      Inflammation, Granulomatous                                                             1 [4.0]                               
      Ulcer                                                                      2 [3.5]                                            
      Subcutaneous Tissue, Thrombosis                                            1 [4.0]                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (50)         (50)         (50)         (50)                                   
      Hyperostosis                                                               1 [3.0]                                            
      Cartilage, Femur, Hyperplasia                    1 [1.0]                                                                      
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Average severity grade (1-minimal;2-mild;3-moderate;4-marked)                                                                    
                                                                                                                                    
                                                             Page   11                                                              
                                                                                                                                   
NTP Experiment-Test: 88004-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT18  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 12/17/03    
Route: RESPIRATORY EXPOSURE WHOLE BODY                          DIVINYLBENZENE                                    Time: 12:01:01    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS MALE                        CONTROL      100 PPM      200 PPM      400 PPM                                
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
MUSCULOSKELETAL SYSTEM - CONT                                                                                                       
      Femur, Fracture                                               1 [4.0]                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (49)         (50)         (50)         (50)                                   
      Compression                                     10 [2.9]      5 [2.4]      8 [2.9]      6 [3.5]                               
      Gliosis                                                                                 1 [3.0]                               
      Hemorrhage                                                    1 [4.0]                   1 [3.0]                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Larynx                                             (49)         (49)         (50)         (49)                                   
      Foreign Body                                     1 [4.0]      2 [4.0]      3 [4.0]      2 [2.5]                               
      Inflammation, Suppurative                                     1 [2.0]      1 [4.0]      1 [1.0]                               
      Epiglottis, Metaplasia, Squamous                                           1 [3.0]      1 [2.0]                               
   Lung                                               (50)         (50)         (50)         (50)                                   
      Congestion                                                                              1 [2.0]                               
      Hemorrhage                                       2 [3.0]      1 [2.0]      4 [1.8]      4 [1.5]                               
      Inflammation, Chronic                                                      1 [3.0]                                            
      Inflammation, Chronic, Diffuse                                             1 [2.0]                                            
      Inflammation, Chronic, Focal                     4 [1.0]      4 [1.5]      5 [1.6]     14 [1.1]                               
      Inflammation, Suppurative                        1 [1.0]                                                                      
      Necrosis                                         1 [2.0]                   1 [4.0]                                            
      Thrombosis                                       1 [4.0]                                                                      
      Alveolar Epithelium, Hyperplasia                 4 [2.5]      8 [1.8]      6 [1.7]      6 [3.2]                               
      Alveolar Epithelium, Hypertrophy                              1 [1.0]      1 [1.0]      2 [1.0]                               
      Alveolus, Hypertrophy                                                                   1 [1.0]                               
      Alveolus, Infiltration Cellular, Focal,                                                                                       
        Histiocyte                                     9 [1.6]     12 [1.6]     11 [1.5]      4 [1.5]                               
      Interstitium, Fibrosis                           1 [2.0]      1 [1.0]      1 [1.0]      1 [1.0]                               
      Mediastinum, Abscess                             1 [3.0]                                                                      
      Mediastinum, Inflammation, Chronic                                         1 [2.0]                                            
      Mediastinum, Pigmentation                                                  1 [4.0]                                            
      Perivascular, Edema                                                                     1 [1.0]                               
      Perivascular, Infiltration Cellular,                                                                                          
        Eosinophil                                                                            1 [1.0]                               
   Nose                                               (50)         (48)         (50)         (49)                                   
      Foreign Body                                     5 [2.0]      1 [3.0]      3 [1.7]                                            
      Inflammation, Suppurative                        5 [2.4]      9 [1.4]     17 [1.7]     10 [1.6]                               
      Glands, Dilatation                               3 [1.7]     30 [1.2]     48 [1.5]     46 [1.5]                               
      Goblet Cell, Hyperplasia                         1 [2.0]      3 [1.7]      7 [1.7]     16 [1.6]                               
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Average severity grade (1-minimal;2-mild;3-moderate;4-marked)                                                                    
                                                                                                                                    
                                                             Page   12                                                              
                                                                                                                                   
NTP Experiment-Test: 88004-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT18  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 12/17/03    
Route: RESPIRATORY EXPOSURE WHOLE BODY                          DIVINYLBENZENE                                    Time: 12:01:01    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS MALE                        CONTROL      100 PPM      200 PPM      400 PPM                                
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
RESPIRATORY SYSTEM - CONT                                                                                                           
      Nasolacrimal Duct, Inflammation, Suppurative     2 [1.0]      6 [1.7]      1 [1.0]      4 [2.3]                               
      Nasopharyngeal Duct, Cyst                                                               1 [4.0]                               
      Nasopharyngeal Duct, Foreign Body                                                       1 [1.0]                               
      Nasopharyngeal Duct, Inflammation,                                                                                            
        Suppurative                                                              1 [2.0]                                            
      Nasopharyngeal Duct, Respiratory Epithelium,                                                                                  
         Hyperplasia                                                                          1 [4.0]                               
      Olfactory Epithelium, Degeneration                           47 [1.6]     49 [1.7]     49 [2.0]                               
      Olfactory Epithelium, Degeneration, Hyaline      4 [1.3]                   2 [1.0]      1 [2.0]                               
      Olfactory Epithelium, Hyperplasia, Basal Cell                21 [1.0]     44 [1.4]     48 [1.7]                               
      Olfactory Epithelium, Metaplasia                              1 [1.0]                   2 [1.5]                               
      Respiratory Epithelium, Hyperplasia              1 [3.0]                                                                      
      Turbinate, Cyst                                               1 [2.0]                                                         
   Pleura                                             (50)         (50)         (50)         (50)                                   
      Mesothelium, Hyperplasia                                                   1 [2.0]                                            
   Trachea                                            (50)         (49)         (50)         (49)                                   
      Glands, Degeneration, Cystic                     1 [2.0]                                5 [1.6]                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                (50)         (48)         (48)         (49)                                   
      Anterior Chamber, Hemorrhage                                               1 [4.0]                                            
      Cornea, Mineralization                                                                  1 [1.0]                               
      Lens, Cataract                                   2 [2.0]      1 [4.0]      3 [3.0]      1 [2.0]                               
      Retina, Atrophy                                               1 [4.0]                                                         
   Harderian Gland                                    (50)         (50)         (50)         (50)                                   
      Atrophy                                                                    1 [4.0]                                            
   Zymbal's Gland                                     (1)                       (3)                                                 
      Inflammation, Suppurative                                                  1 [4.0]                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (50)         (49)         (50)         (49)                                   
      Cyst                                                          1 [4.0]                   1 [4.0]                               
      Nephropathy, Chronic                            37 [1.8]     41 [1.5]     41 [2.1]     45 [1.8]                               
      Cortex, Infarct                                  1 [4.0]      1 [2.0]                                                         
      Cortex, Renal Tubule, Degeneration                                                      1 [2.0]                               
      Cortex, Renal Tubule, Hyperplasia                1 [2.0]      2 [1.0]                   2 [4.0]                               
      Cortex, Renal Tubule, Hypertrophy                1 [1.0]                                                                      
      Medulla, Infarct                                              1 [4.0]                                                         
      Medulla, Infiltration Cellular, Lipocyte                      1 [3.0]                                                         
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Average severity grade (1-minimal;2-mild;3-moderate;4-marked)                                                                    
                                                                                                                                    
                                                             Page   13                                                              
                                                                                                                                   
NTP Experiment-Test: 88004-05         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT18  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 12/17/03    
Route: RESPIRATORY EXPOSURE WHOLE BODY                          DIVINYLBENZENE                                    Time: 12:01:01    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         FISCHER 344 RATS MALE                        CONTROL      100 PPM      200 PPM      400 PPM                                
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
URINARY SYSTEM - CONT                                                                                                               
      Papilla, Renal Tubule, Dilatation                                                       1 [4.0]                               
      Pelvis, Transitional Epithelium, Hyperplasia     1 [4.0]      1 [2.0]                                                         
      Pelvis, Transitional Epithelium,                                                                                              
        Mineralization                                                                        1 [3.0]                               
   Urethra                                                                      (1)                                                 
      Transitional Epithelium, Hyperplasia                                       1 [3.0]                                            
   Urinary Bladder                                    (50)         (49)         (50)         (49)                                   
      Calculus Micro Observation Only                  4 [2.0]      2 [2.5]      4 [3.3]      4 [2.0]                               
      Hemorrhage                                       2 [3.0]      1 [4.0]      1 [3.0]                                            
      Transitional Epithelium, Hyperplasia                                       1 [2.0]                                            
                                                                                                                                    
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Average severity grade (1-minimal;2-mild;3-moderate;4-marked)                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page   14                                                              
                                                                                                                                   
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                             ----------              END OF REPORT             ----------                                           
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