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https://ntp.niehs.nih.gov/go/12933

TDMS Study 56348-04 Pathology Tables

NTP Experiment-Test: 56348-04         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 07/05/01
Route: DOSED FEED                                                   CITRAL                                        Time: 14:03:02




       Facility:  Battelle Columbus Laboratory

       Chemical CAS #:  5392-40-5

       Lock Date:  03/25/99

       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: 56348-04         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 07/05/01    
Route: DOSED FEED                                                   CITRAL                                        Time: 14:03:02    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE FEMALE                           UNTREAT      VEHICLE      500 PPM      1000 PPM     2000 PPM                  
                                                      CONTROL      CONTROL                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
DISPOSITION SUMMARY                                                                                                                 
                                                                                                                                    
  Animals Initially In Study                          50           50           50           50           50                        
  Early Deaths                                                                                                                      
    Natural Death                                      5            3            3            3            5                        
    Moribund Sacrifice                                 4            5            2            4            5                        
    Accidently Killed                                  1                                                                            
  Survivors                                                                                                                         
    Terminal Sacrifice                                40           41           45           43           40                        
  Missing                                                           1                                                               
                                                                                                                                    
  Animals Examined Microscopically                    50           49           50           50           50                        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Esophagus                                          (50)         (49)         (50)         (50)         (50)                      
      Hyperplasia, Basal Cell                                       1 [3.0]                                                         
   Intestine Small, Duodenum                          (50)         (49)         (50)         (50)         (49)                      
      Ectasia                                          1 [3.0]                                                                      
      Inflammation, Chronic                            1 [1.0]      1 [3.0]      1 [1.0]      1 [1.0]                               
      Ulcer                                                                                   1 [3.0]                               
      Epithelium, Hyperplasia, Focal                   1 [1.0]      1 [2.0]                                                         
      Epithelium, Metaplasia, Squamous                 1 [1.0]                                                                      
   Intestine Small, Jejunum                           (50)         (49)         (50)         (50)         (50)                      
      Inflammation, Chronic Active                                  1 [3.0]                                                         
      Ulcer                                                         1 [2.0]                                1 [3.0]                  
      Muscularis, Infiltration Cellular, Lymphocyte                                                        1 [1.0]                  
      Peyer's Patch, Hyperplasia, Lymphoid             2 [3.5]                                2 [3.0]                               
      Peyer's Patch, Infiltration Cellular, Plasma                                                                                  
          Cell                                                                                1 [3.0]                               
   Intestine Small, Ileum                             (50)         (49)         (50)         (50)         (50)                      
      Inflammation, Chronic                            1 [2.0]                                                                      
      Inflammation, Granulomatous                      1 [4.0]                                                                      
      Ulcer                                            1 [4.0]                                                                      
   Liver                                              (50)         (49)         (50)         (50)         (50)                      
      Basophilic Focus                                                                        1                                     
      Clear Cell Focus                                 3                         2            6                                     
      Eosinophilic Focus                                                         1                         1                        
      Hematopoietic Cell Proliferation                 1 [2.0]      1 [1.0]                   3 [2.7]                               
      Hemorrhage                                                    1 [1.0]                   1 [1.0]                               
      Infarct                                                       1 [1.0]                                                         
      Infiltration Cellular, Lymphocyte               16 [1.0]     18 [1.1]     12 [1.0]     27 [1.2]     25 [1.0]                  
      Inflammation, Granulomatous                     20 [1.0]     14 [1.0]     20 [1.0]     16 [1.0]     11 [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    2                                                              
                                                                                                                                   
NTP Experiment-Test: 56348-04         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 07/05/01    
Route: DOSED FEED                                                   CITRAL                                        Time: 14:03:02    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE FEMALE                           UNTREAT      VEHICLE      500 PPM      1000 PPM     2000 PPM                  
                                                      CONTROL      CONTROL                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Mineralization                                                1 [3.0]                                                         
      Mixed Cell Focus                                 4            5            1            4            3                        
      Necrosis, Focal                                  2 [2.0]      3 [2.0]      2 [1.0]      3 [1.3]                               
      Vacuolization Cytoplasmic, Focal                 4 [1.0]      3 [1.0]      5 [1.0]      3 [1.0]      5 [1.0]                  
      Bile Duct, Cyst                                                            1 [2.0]                                            
      Bile Duct, Inflammation, Granulomatous           1 [1.0]                                                                      
      Centrilobular, Degeneration                      1 [2.0]      1 [3.0]      1 [3.0]      1 [3.0]      2 [1.0]                  
   Mesentery                                          (5)          (3)          (1)          (6)          (2)                       
      Infiltration Cellular, Mast Cell                 1 [2.0]                                                                      
      Inflammation, Granulomatous                      1 [2.0]                                1 [4.0]                               
      Thrombosis                                                                                           1 [3.0]                  
      Artery, Inflammation, Chronic                                 1 [3.0]                   1 [2.0]                               
      Fat, Necrosis                                    3 [2.3]      2 [2.0]      1 [2.0]      2 [2.0]      1 [2.0]                  
   Oral Mucosa                                        (50)         (49)         (50)         (50)         (50)                      
      Infiltration Cellular, Mast Cell                 1 [1.0]                                1 [1.0]                               
      Inflammation, Chronic Active                    20 [1.4]     14 [1.4]     32 [1.9]     35 [1.8]     32 [1.5]                  
      Ulcer                                            6 [1.3]      6 [1.2]     15 [1.9]     22 [1.6]     15 [1.5]                  
   Pancreas                                           (50)         (49)         (50)         (50)         (50)                      
      Fibrosis, Focal                                                            1 [2.0]                                            
      Hypertrophy, Focal                                            1 [1.0]                                                         
      Infiltration Cellular, Mast Cell                 1 [2.0]                                                                      
      Inflammation, Chronic                                                      1 [1.0]                                            
      Acinus, Atrophy                                  1 [4.0]                                             2 [3.0]                  
      Acinus, Hypertrophy, Focal                       1 [2.0]                                2 [1.0]                               
      Duct, Cyst                                       2 [3.5]      1 [3.0]      1 [3.0]                   1 [3.0]                  
      Duct, Inflammation, Chronic                      1 [4.0]                                                                      
   Salivary Glands                                    (49)         (49)         (50)         (50)         (49)                      
      Artery, Inflammation, Chronic                                 1 [2.0]                   1 [2.0]                               
      Parotid Gland, Inflammation, Chronic                          1 [1.0]                                                         
   Stomach, Forestomach                               (50)         (49)         (50)         (50)         (50)                      
      Edema, Diffuse                                                                                       1 [3.0]                  
      Edema, Focal                                     1 [1.0]                                                                      
      Infiltration Cellular, Lymphocyte                1 [1.0]                                                                      
      Inflammation, Chronic, Focal                                               1 [2.0]                                            
      Ulcer                                            1 [2.0]      1 [2.0]      1 [2.0]                   2 [1.5]                  
      Epithelium, Hyperplasia, Focal                   3 [1.3]      2 [2.5]      3 [2.0]      1 [1.0]      2 [2.0]                  
   Stomach, Glandular                                 (50)         (49)         (50)         (50)         (50)                      
      Edema, Diffuse                                                                                       1 [3.0]                  
      Mineralization                                                1 [3.0]                                                         
      Ulcer                                            1 [2.0]      1 [2.0]                                                         
      Artery, Inflammation, Chronic                    1 [1.0]                                                                      
      Epithelium, Hyperplasia, Atypical, Focal                      1 [1.0]                                                         
      Glands, Ectasia                                               1 [1.0]                                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    3                                                              
                                                                                                                                   
NTP Experiment-Test: 56348-04         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 07/05/01    
Route: DOSED FEED                                                   CITRAL                                        Time: 14:03:02    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE FEMALE                           UNTREAT      VEHICLE      500 PPM      1000 PPM     2000 PPM                  
                                                      CONTROL      CONTROL                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Muscularis, Inflammation, Acute                               1 [2.0]                                                         
   Tooth                                              (1)                                                                           
      Pulp, Inflammation, Chronic                      1 [2.0]                                                                      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Blood Vessel                                       (50)         (49)         (50)         (50)         (50)                      
      Aorta, Mineralization                                         1 [4.0]      1 [3.0]      1 [2.0]                               
      Aorta, Adventitia, Inflammation, Chronic         1 [1.0]                                                                      
      Pulmonary Vein, Hemorrhage                       1 [2.0]                                                                      
   Heart                                              (50)         (49)         (50)         (50)         (50)                      
      Artery, Inflammation, Chronic                                 1 [2.0]      2 [1.0]      1 [3.0]      2 [2.0]                  
      Artery, Mineralization                                                     1 [3.0]                                            
      Atrium, Inflammation, Chronic                                              1 [1.0]                   1 [2.0]                  
      Atrium, Thrombosis                                            1 [1.0]                                                         
      Coronary Artery, Inflammation, Chronic                                     1 [1.0]                                            
      Myocardium, Degeneration                         3 [1.3]      1 [2.0]      1 [1.0]      1 [1.0]      1 [2.0]                  
      Myocardium, Inflammation, Chronic                                                                    1 [1.0]                  
      Myocardium, Mineralization                                                 1 [2.0]      1 [1.0]                               
      Valve, Inflammation, Chronic                     2 [4.0]      2 [3.0]      4 [2.5]                   1 [4.0]                  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (50)         (49)         (50)         (50)         (50)                      
      Accessory Adrenal Cortical Nodule                                                       1 [1.0]                               
      Atrophy                                                                    1 [1.0]                                            
      Hematopoietic Cell Proliferation                 1 [2.0]      1 [2.0]      1 [1.0]                                            
      Hyperplasia, Focal                               1 [2.0]                                2 [1.0]      2 [1.0]                  
      Hypertrophy, Focal                               3 [1.0]      3 [1.7]      2 [1.0]      2 [1.0]      3 [1.0]                  
      Inflammation, Granulomatous                                                                          1 [1.0]                  
      Vacuolization Cytoplasmic, Focal                                           1 [2.0]                                            
      Subcapsular, Hyperplasia                        47 [1.0]     49 [1.1]     50 [1.0]     49 [1.0]     49 [1.1]                  
      Subcapsular, Hyperplasia, Focal                                                                      1 [1.0]                  
   Adrenal Medulla                                    (50)         (49)         (50)         (50)         (50)                      
      Hyperplasia, Focal                               1 [1.0]      1 [1.0]                   2 [2.0]      2 [1.0]                  
   Islets, Pancreatic                                 (50)         (49)         (50)         (50)         (50)                      
      Hyperplasia                                      2 [1.0]                   3 [1.3]      1 [2.0]      2 [1.5]                  
   Parathyroid Gland                                  (43)         (42)         (35)         (40)         (43)                      
      Inflammation, Granulomatous                      1 [1.0]                                                                      
   Pituitary Gland                                    (49)         (48)         (50)         (49)         (49)                      
      Angiectasis                                                                                          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    4                                                              
                                                                                                                                   
NTP Experiment-Test: 56348-04         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 07/05/01    
Route: DOSED FEED                                                   CITRAL                                        Time: 14:03:02    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE FEMALE                           UNTREAT      VEHICLE      500 PPM      1000 PPM     2000 PPM                  
                                                      CONTROL      CONTROL                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ENDOCRINE SYSTEM - CONT                                                                                                             
      Cyst                                                                       1 [1.0]      1 [1.0]                               
      Pars Distalis, Hyperplasia, Focal                7 [1.1]      7 [1.3]      7 [1.6]     10 [1.4]      9 [1.3]                  
      Pars Nervosa, Mineralization                                               1 [3.0]                                            
   Thyroid Gland                                      (48)         (49)         (50)         (50)         (49)                      
      Inflammation, Chronic, Focal                                  1 [1.0]                                                         
      Inflammation, Granulomatous                      2 [1.0]                                                                      
      Follicle, Hyperplasia                                                      1 [2.0]                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Clitoral Gland                                     (47)         (48)         (50)         (47)         (49)                      
      Cyst                                                                       1 [2.0]                                            
      Inflammation, Granulomatous                                                1 [2.0]                                            
      Inflammation, Suppurative                                                                            1 [2.0]                  
   Ovary                                              (50)         (49)         (50)         (49)         (50)                      
      Angiectasis                                                   1 [3.0]                   2 [2.0]                               
      Cyst                                            19 [2.4]     20 [2.1]     23 [2.0]     16 [1.9]     17 [1.9]                  
      Dysplasia, Focal                                 1 [1.0]      1 [1.0]                                                         
      Necrosis, Focal                                  1 [3.0]                                                                      
      Thrombosis                                                                 2 [4.0]                                            
      Interstitial Cell, Hyperplasia                                                          1 [3.0]                               
   Uterus                                             (50)         (49)         (50)         (50)         (50)                      
      Inflammation, Suppurative                                                  1 [2.0]                                            
      Thrombosis                                                    1 [3.0]                   1 [4.0]                               
      Ulcer                                                                                   1 [4.0]                               
      Endometrium, Hyperplasia, Cystic                43 [1.4]     45 [1.4]     43 [1.5]     44 [1.3]     35 [1.3]                  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (50)         (49)         (50)         (50)         (50)                      
      Hyperplasia                                      2 [2.5]     11 [1.8]      6 [1.8]      6 [1.8]     13 [2.4]                  
   Lymph Node                                         (2)          (1)                       (7)          (5)                       
      Lumbar, Hyperplasia, Lymphoid                                                           1 [2.0]                               
      Pancreatic, Hyperplasia, Lymphoid                                                       1 [3.0]                               
      Renal, Hyperplasia, Lymphoid                                                            1 [4.0]                               
   Lymph Node, Mandibular                             (49)         (49)         (48)         (47)         (44)                      
                                                                                                                                    
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: 56348-04         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 07/05/01    
Route: DOSED FEED                                                   CITRAL                                        Time: 14:03:02    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE FEMALE                           UNTREAT      VEHICLE      500 PPM      1000 PPM     2000 PPM                  
                                                      CONTROL      CONTROL                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
HEMATOPOIETIC SYSTEM - CONT                                                                                                         
      Amyloid Deposition                               1 [4.0]                                                                      
      Hyperplasia, Lymphoid                                         1 [2.0]                                                         
   Lymph Node, Mesenteric                             (49)         (47)         (48)         (50)         (49)                      
      Atrophy                                          1 [1.0]                                                                      
      Fibrosis                                         1 [3.0]                                                                      
      Hematopoietic Cell Proliferation                              1 [2.0]                                                         
      Hyperplasia, Lymphoid                            1 [3.0]                   1 [2.0]                                            
      Infiltration Cellular, Plasma Cell               3 [1.3]      2 [3.0]      1 [2.0]      2 [2.5]      1 [1.0]                  
      Infiltration Cellular, Polymorphonuclear                                                1 [2.0]                               
      Inflammation, Granulomatous                      1 [2.0]                                                                      
   Spleen                                             (50)         (49)         (50)         (49)         (50)                      
      Hematopoietic Cell Proliferation                17 [1.8]     14 [1.9]     19 [2.0]     10 [1.8]     19 [1.7]                  
      Lymphoid Follicle, Atrophy                       8 [2.9]      4 [2.5]      7 [2.3]      2 [3.5]      4 [2.3]                  
      Lymphoid Follicle, Hyperplasia                   8 [1.6]     14 [1.7]      7 [1.0]     12 [1.8]     13 [1.5]                  
   Thymus                                             (47)         (48)         (49)         (48)         (50)                      
      Atrophy                                         26 [2.0]     31 [2.3]     33 [1.7]     24 [2.0]     19 [2.0]                  
      Hyperplasia, Lymphoid                           11 [1.6]      7 [1.4]      5 [1.8]     16 [1.6]     14 [1.3]                  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (50)         (49)         (50)         (49)         (49)                      
      Hyperplasia                                                   1 [2.0]                                                         
      Hyperplasia, Cystic                              1 [1.0]                                             1 [3.0]                  
   Skin                                               (50)         (49)         (50)         (50)         (50)                      
      Necrosis                                                      1 [3.0]                                                         
      Dermis, Fibrosis, Focal                          1 [1.0]                                                                      
      Subcutaneous Tissue, Fibrosis                                                           1 [2.0]                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (50)         (49)         (50)         (50)         (50)                      
      Fibrosis                                        19 [1.5]     11 [1.7]     22 [1.9]     21 [1.5]     18 [1.7]                  
      Fracture                                         1 [4.0]                                                                      
      Joint, Inflammation, Chronic                                                            1 [1.0]                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (50)         (48)         (50)         (50)         (50)                      
      Hemorrhage, Focal                                1 [2.0]                                                                      
      Hydrocephalus                                                              1 [2.0]      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    6                                                              
                                                                                                                                   
NTP Experiment-Test: 56348-04         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 07/05/01    
Route: DOSED FEED                                                   CITRAL                                        Time: 14:03:02    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE FEMALE                           UNTREAT      VEHICLE      500 PPM      1000 PPM     2000 PPM                  
                                                      CONTROL      CONTROL                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
NERVOUS SYSTEM - CONT                                                                                                               
      Necrosis, Focal                                  1 [3.0]                                                                      
      Artery, Meninges, Inflammation, Chronic                                                 1 [2.0]                               
      Hypothalamus, Compression                                     1 [3.0]                                1 [4.0]                  
      Meninges, Inflammation, Acute                    1 [4.0]                                                                      
   Peripheral Nerve                                                (1)                                    (2)                       
      Axon, Degeneration                                            1 [3.0]                                2 [2.0]                  
   Spinal Cord                                                     (1)                                    (2)                       
      Artery, Inflammation, Chronic                                 1 [4.0]                                                         
      Axon, Degeneration                                            1 [4.0]                                1 [3.0]                  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Lung                                               (50)         (49)         (50)         (50)         (50)                      
      Hemorrhage                                       1 [1.0]                   2 [1.0]      1 [1.0]                               
      Inflammation, Acute, Focal                                                              1 [1.0]                               
      Inflammation, Granulomatous                      1 [3.0]                   2 [1.0]      3 [1.0]      2 [1.0]                  
      Metaplasia, Osseous                                                                     1 [1.0]                               
      Mineralization                                                1 [4.0]                                                         
      Alveolar Epithelium, Hyperplasia, Focal          2 [1.5]                   3 [1.7]      2 [1.0]      2 [1.0]                  
      Alveolus, Inflammation, Chronic, Focal           1 [1.0]                                                                      
   Nose                                               (50)         (49)         (50)         (50)         (50)                      
      Hemorrhage                                                    1 [1.0]                                                         
      Inflammation, Suppurative                                                                            1 [2.0]                  
   Trachea                                            (50)         (49)         (50)         (50)         (49)                      
      Glands, Inflammation, Suppurative                1 [1.0]                                                                      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                (1)                                                                           
      Synechia                                         1 [2.0]                                                                      
      Retrobulbar, Fibrosis                            1 [2.0]                                                                      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (50)         (49)         (50)         (50)         (50)                      
      Hydronephrosis                                   1 [2.0]                                                                      
      Infarct                                          4 [1.8]      1 [1.0]      1 [1.0]      5 [1.6]      2 [2.5]                  
      Inflammation, Suppurative                                                  1 [2.0]                                            
      Metaplasia, Osseous                                                        3 [1.0]      1 [1.0]                               
      Nephropathy                                     13 [1.0]      9 [1.0]     16 [1.0]     15 [1.2]     17 [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    7                                                              
                                                                                                                                   
NTP Experiment-Test: 56348-04         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 07/05/01    
Route: DOSED FEED                                                   CITRAL                                        Time: 14:03:02    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE FEMALE                           UNTREAT      VEHICLE      500 PPM      1000 PPM     2000 PPM                  
                                                      CONTROL      CONTROL                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
URINARY SYSTEM - CONT                                                                                                               
      Artery, Inflammation, Chronic                                 1 [3.0]                                                         
      Artery, Mineralization                                                     1 [3.0]                                            
      Capsule, Inflammation, Granulomatous                                                    1 [1.0]                               
      Glomerulus, Inflammation, Chronic                1 [3.0]                                                                      
      Papilla, Fibrosis, Focal                                      1 [1.0]                                                         
      Papilla, Necrosis                                                                       1 [1.0]                               
      Pelvis, Inflammation, Granulomatous              1 [2.0]                                                                      
      Renal Tubule, Cyst                               1 [1.0]      1 [1.0]                                                         
      Renal Tubule, Cytoplasmic Alteration                                                                 1 [2.0]                  
      Renal Tubule, Degeneration, Focal                                                       1 [2.0]                               
      Renal Tubule, Mineralization                     3 [1.0]      4 [1.0]     14 [1.0]     18 [1.0]      6 [1.2]                  
      Renal Tubule, Necrosis                                                     1 [3.0]                                            
      Transitional Epithelium, 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: 56348-04         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 07/05/01    
Route: DOSED FEED                                                   CITRAL                                        Time: 14:03:02    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE MALE                             UNTREAT      VEHICLE      500 PPM      1000 PPM     2000 PPM                  
                                                      CONTROL      CONTROL                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
DISPOSITION SUMMARY                                                                                                                 
                                                                                                                                    
  Animals Initially In Study                          50           50           50           50           50                        
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                 1            4            2            6            3                        
    Natural Death                                      1            3            8            2            7                        
  Survivors                                                                                                                         
    Terminal Sacrifice                                47           42           40           42           40                        
    Natural Death                                      1                                                                            
    Accidently Killed                                               1                                                               
                                                                                                                                    
  Animals Examined Microscopically                    50           50           50           50           50                        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Gallbladder                                        (50)         (50)         (48)         (48)         (49)                      
      Epithelium, Cytoplasmic Alteration                                         1 [4.0]                                            
   Intestine Large, Colon                             (50)         (50)         (50)         (50)         (50)                      
      Serosa, Inflammation, Granulomatous                                                     1 [2.0]                               
   Intestine Large, Rectum                            (50)         (50)         (50)         (50)         (50)                      
      Ulcer                                                                                   1 [4.0]                               
   Intestine Large, Cecum                             (50)         (50)         (50)         (50)         (50)                      
      Edema                                                                                   1 [3.0]                               
      Serosa, Inflammation, Granulomatous              1 [3.0]                                                                      
   Intestine Small, Duodenum                          (50)         (50)         (50)         (49)         (50)                      
      Epithelium, Hyperplasia, Focal                   1 [1.0]                                                                      
      Epithelium, Hypertrophy                          1 [2.0]                                                                      
      Epithelium, Metaplasia, Focal, Squamous          1 [1.0]                                                                      
      Epithelium, Necrosis, Focal                      2 [1.0]                                                                      
      Peyer's Patch, Inflammation, Granulomatous                                 1 [1.0]                                            
   Intestine Small, Jejunum                           (50)         (50)         (50)         (50)         (50)                      
      Muscularis, Atrophy                              1 [3.0]                                                                      
      Muscularis, Inflammation, Chronic                                                       1 [1.0]      1 [2.0]                  
      Peyer's Patch, Hyperplasia, Lymphoid                          1 [2.0]                   1 [3.0]                               
      Peyer's Patch, Infiltration Cellular, Plasma                                                                                  
          Cell                                                                                1 [4.0]                               
      Peyer's Patch, Inflammation, Suppurative         1 [1.0]                                                                      
      Serosa, Inflammation, Granulomatous              1 [2.0]      2 [2.0]                                                         
   Intestine Small, Ileum                             (50)         (50)         (50)         (50)         (50)                      
      Inflammation, Chronic                                                                   1 [3.0]      1 [2.0]                  
      Inflammation, Granulomatous                                                             1 [1.0]                               
      Serosa, Inflammation, Granulomatous                                        1 [1.0]      1 [1.0]                               
   Liver                                              (50)         (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    9                                                              
                                                                                                                                   
NTP Experiment-Test: 56348-04         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 07/05/01    
Route: DOSED FEED                                                   CITRAL                                        Time: 14:03:02    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE MALE                             UNTREAT      VEHICLE      500 PPM      1000 PPM     2000 PPM                  
                                                      CONTROL      CONTROL                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Angiectasis                                                                                          2 [1.0]                  
      Basophilic Focus                                                           1                                                  
      Clear Cell Focus                                 8            9            3            7            2                        
      Eosinophilic Focus                               3            4            2            5            1                        
      Hematopoietic Cell Proliferation                 1 [1.0]                   2 [2.0]                                            
      Infiltration Cellular, Mast Cell                 1 [1.0]      1 [1.0]                                                         
      Infiltration Cellular, Lymphocyte                2 [1.0]      1 [1.0]      4 [1.0]      5 [1.0]      4 [1.0]                  
      Inflammation, Granulomatous                      9 [1.1]      7 [1.0]     12 [1.0]     12 [1.1]      7 [1.1]                  
      Mixed Cell Focus                                 9           10            8            9            7                        
      Necrosis, Focal                                  3 [1.7]      1 [2.0]      4 [1.5]      5 [1.8]      1 [1.0]                  
      Vacuolization Cytoplasmic, Focal                 6 [1.2]     11 [1.0]      7 [1.0]      4 [1.0]      4 [1.0]                  
      Bile Duct, Cyst                                                            1 [1.0]                                            
      Bile Duct, Cytoplasmic Alteration                                                                    1 [1.0]                  
      Bile Duct, Hyperplasia                                        1 [2.0]                                                         
      Centrilobular, Degeneration                      1 [2.0]      1 [2.0]      1 [1.0]                                            
      Periportal, Degeneration                                      1 [2.0]                                                         
      Periportal, Fibrosis                                                                                 1 [1.0]                  
   Mesentery                                          (6)          (3)          (2)          (3)          (3)                       
      Inflammation, Chronic                            1 [2.0]      1 [1.0]                   1 [1.0]                               
      Inflammation, Granulomatous                      3 [1.7]      1 [3.0]      1 [1.0]                   1 [2.0]                  
      Artery, Inflammation, Chronic                                              1 [3.0]                   1 [3.0]                  
      Fat, Necrosis                                    1 [2.0]      1 [2.0]                   2 [2.0]      1 [2.0]                  
   Oral Mucosa                                        (50)         (50)         (50)         (50)         (50)                      
      Inflammation, Chronic Active                     6 [2.0]     12 [1.8]     16 [1.9]     21 [1.9]     21 [1.5]                  
      Ulcer                                            4 [2.3]      9 [1.8]      8 [1.6]     12 [1.4]     10 [1.6]                  
   Pancreas                                           (50)         (50)         (50)         (50)         (50)                      
      Inflammation, Chronic Active                                               1 [1.0]                                            
   Salivary Glands                                    (50)         (50)         (50)         (50)         (50)                      
      Inflammation, Chronic                                                                   1 [1.0]                               
      Duct, Hypertrophy, Focal                                      1 [2.0]                                                         
   Stomach, Forestomach                               (50)         (50)         (49)         (50)         (50)                      
      Inflammation, Chronic                                                                   1 [2.0]                               
      Inflammation, Suppurative                                     2 [1.5]                                2 [1.5]                  
      Ulcer                                            1 [2.0]                                2 [2.5]                               
      Epithelium, Cyst                                              2 [2.0]                                                         
      Epithelium, Hyperkeratosis, Diffuse              1 [1.0]      1 [2.0]                                2 [1.0]                  
      Epithelium, Hyperplasia, Diffuse                 1 [1.0]                                2 [3.0]                               
      Epithelium, Hyperplasia, Focal                   1 [1.0]      5 [2.4]                   2 [2.5]      2 [2.5]                  
   Stomach, Glandular                                 (50)         (50)         (50)         (50)         (50)                      
      Inflammation, Chronic, Focal                                               1 [1.0]                                            
      Ulcer                                                                                   2 [2.0]                               
      Epithelium, Hyperplasia, Focal                   2 [1.5]                                             1 [2.0]                  
      Epithelium, Inflammation, Acute, Focal                        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   10                                                              
                                                                                                                                   
NTP Experiment-Test: 56348-04         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 07/05/01    
Route: DOSED FEED                                                   CITRAL                                        Time: 14:03:02    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE MALE                             UNTREAT      VEHICLE      500 PPM      1000 PPM     2000 PPM                  
                                                      CONTROL      CONTROL                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Glands, Ectasia                                  1 [1.0]      1 [1.0]                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Blood Vessel                                       (50)         (50)         (50)         (50)         (50)                      
      Aorta, Adventitia, Inflammation, Chronic                                                1 [1.0]                               
   Heart                                              (50)         (50)         (50)         (50)         (50)                      
      Artery, Inflammation, Chronic                                              1 [2.0]                   1 [1.0]                  
      Atrium, Thrombosis                                            1 [4.0]                                                         
      Coronary Artery, Inflammation, Chronic           1 [1.0]                                             1 [2.0]                  
      Myocardium, Degeneration                         1 [1.0]      2 [1.0]                   3 [1.0]      1 [1.0]                  
      Myocardium, Inflammation, Chronic                                                       1 [2.0]                               
      Valve, Inflammation, Chronic                                  2 [4.0]      1 [3.0]      1 [3.0]      2 [4.0]                  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (50)         (50)         (50)         (50)         (50)                      
      Fibrosis, Focal                                  1 [1.0]                                1 [1.0]                               
      Hyperplasia                                                                             1 [1.0]                               
      Hyperplasia, Focal                               1 [1.0]                   3 [1.0]      1 [1.0]      5 [1.6]                  
      Hypertrophy                                                   1 [1.0]                                                         
      Hypertrophy, Focal                              25 [1.5]     25 [1.3]     17 [1.1]     28 [1.1]     22 [1.0]                  
      Inflammation, Granulomatous                                                1 [1.0]                                            
      Mineralization, Focal                                                      1 [1.0]                                            
      Vacuolization Cytoplasmic, Focal                 1 [1.0]                                             1 [1.0]                  
      Subcapsular, Hyperplasia                        36 [1.0]     42 [1.2]     40 [1.1]     47 [1.0]     39 [1.1]                  
      Subcapsular, Hyperplasia, Focal                  1 [1.0]                                                                      
   Adrenal Medulla                                    (49)         (50)         (50)         (50)         (50)                      
      Hyperplasia, Focal                                                                      1 [3.0]      1 [1.0]                  
   Islets, Pancreatic                                 (50)         (50)         (50)         (50)         (50)                      
      Hyperplasia                                     15 [1.1]     18 [1.3]     28 [1.4]     30 [1.1]      9 [1.0]                  
   Parathyroid Gland                                  (43)         (43)         (39)         (44)         (37)                      
      Cyst                                                                                                 2 [1.5]                  
      Hyperplasia, Focal                                            1 [1.0]                                                         
   Pituitary Gland                                    (50)         (48)         (49)         (47)         (50)                      
      Cyst                                             1 [1.0]                   1 [1.0]      1 [1.0]      1 [1.0]                  
      Pars Distalis, Hyperplasia, Focal                                          1 [1.0]                   3 [1.0]                  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY 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   11                                                              
                                                                                                                                   
NTP Experiment-Test: 56348-04         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 07/05/01    
Route: DOSED FEED                                                   CITRAL                                        Time: 14:03:02    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE MALE                             UNTREAT      VEHICLE      500 PPM      1000 PPM     2000 PPM                  
                                                      CONTROL      CONTROL                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Epididymis                                         (50)         (50)         (50)         (50)         (50)                      
      Granuloma Sperm                                               1 [2.0]                                1 [3.0]                  
      Inflammation, Chronic Active                     1 [1.0]                                                                      
      Inflammation, Granulomatous                                                             1 [2.0]                               
   Preputial Gland                                    (50)         (50)         (50)         (50)         (50)                      
      Atrophy                                                                                 1 [4.0]                               
      Cyst                                            17 [2.8]     14 [2.8]     19 [2.8]     18 [2.8]     12 [3.0]                  
      Inflammation, Granulomatous                                   3 [2.0]      1 [3.0]      2 [2.0]      1 [1.0]                  
      Inflammation, Suppurative                        2 [2.5]      3 [1.7]      2 [3.0]      1 [2.0]      4 [2.5]                  
   Prostate                                           (50)         (50)         (50)         (50)         (50)                      
      Inflammation, Chronic Active                     1 [2.0]                   1 [3.0]                                            
      Artery, Inflammation, Chronic                                              1 [2.0]                                            
   Seminal Vesicle                                    (50)         (50)         (50)         (50)         (50)                      
      Fibrosis                                                                   1 [3.0]      3 [1.3]                               
   Testes                                             (50)         (50)         (50)         (50)         (50)                      
      Germinal Epithelium, Degeneration                4 [1.0]      2 [1.5]                   4 [1.0]      4 [1.3]                  
      Germinal Epithelium, Mineralization                                        1 [1.0]                   1 [1.0]                  
      Tunic, Mineralization                                                                   1 [1.0]      1 [1.0]                  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (50)         (50)         (50)         (50)         (50)                      
      Hyperplasia                                      9 [1.9]     19 [1.5]     18 [2.1]     14 [1.6]     14 [1.8]                  
      Inflammation, Focal, Suppurative                 1 [1.0]                                                                      
   Lymph Node, Mandibular                             (48)         (45)         (47)         (47)         (49)                      
      Infiltration Cellular, Mast Cell                 1 [3.0]                                                                      
   Lymph Node, Mesenteric                             (48)         (47)         (49)         (48)         (50)                      
      Congestion                                                                              1 [3.0]                               
      Hematopoietic Cell Proliferation                                                                     1 [2.0]                  
      Hyperplasia, Lymphoid                                                      1 [3.0]                                            
      Infiltration Cellular, Plasma Cell               1 [3.0]                                1 [4.0]                               
      Infiltration Cellular, Histiocyte                1 [2.0]                                1 [4.0]                               
      Inflammation, Granulomatous                      1 [2.0]                                1 [2.0]                               
   Spleen                                             (50)         (50)         (49)         (50)         (50)                      
      Hematopoietic Cell Proliferation                17 [1.3]     13 [1.8]     18 [1.9]     13 [2.0]     11 [1.7]                  
      Infiltration Cellular, Mast Cell                 1 [2.0]      1 [1.0]                                                         
      Lymphoid Follicle, Atrophy                       3 [2.7]      4 [2.8]      5 [1.8]      3 [3.3]      6 [2.2]                  
      Lymphoid Follicle, Hyperplasia                   6 [1.7]      8 [1.8]      3 [1.3]      3 [2.3]      5 [1.2]                  
                                                                                                                                    
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: 56348-04         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 07/05/01    
Route: DOSED FEED                                                   CITRAL                                        Time: 14:03:02    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE MALE                             UNTREAT      VEHICLE      500 PPM      1000 PPM     2000 PPM                  
                                                      CONTROL      CONTROL                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
HEMATOPOIETIC SYSTEM - CONT                                                                                                         
   Thymus                                             (50)         (49)         (48)         (48)         (46)                      
      Atrophy                                         41 [2.2]     43 [2.0]     39 [2.3]     32 [2.2]     41 [1.9]                  
      Ectopic Parathyroid Gland                                                  1 [1.0]                                            
      Hyperplasia, Lymphoid                                                      1 [2.0]                                            
      Inflammation, Suppurative                                                               1 [4.0]                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Skin                                               (50)         (50)         (50)         (50)         (50)                      
      Cyst Epithelial Inclusion                                                               1                                     
      Dermis, Inflammation, Chronic, Focal                                                    1 [1.0]                               
      Epidermis, Hyperplasia, Focal                    2 [1.0]                   1 [3.0]                                            
      Subcutaneous Tissue, Inflammation,                                                                                            
          Granulomatous                                                          1 [3.0]      1 [3.0]                               
      Subcutaneous Tissue, Inflammation,                                                                                            
          Suppurative                                                                                      1 [3.0]                  
      Subcutaneous Tissue, Necrosis                                              1 [1.0]                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (50)         (50)         (50)         (50)         (50)                      
      Fibrosis                                                      1 [2.0]      3 [1.3]                   1 [1.0]                  
      Inflammation, Granulomatous                                                             1 [2.0]                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (50)         (50)         (50)         (50)         (50)                      
      Cyst Epithelial Inclusion                                                               1                                     
   Peripheral Nerve                                                                          (1)                                    
      Axon, Degeneration                                                                      1 [3.0]                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Lung                                               (50)         (50)         (50)         (50)         (50)                      
      Hemorrhage                                                                 6 [1.3]      2 [1.5]                               
      Inflammation, Chronic, Focal                     1 [1.0]                                                                      
      Inflammation, Granulomatous                                   1 [1.0]                   1 [1.0]      1 [1.0]                  
      Alveolar Epithelium, Hyperplasia                                                        1 [3.0]                               
      Alveolar Epithelium, Hyperplasia, Focal          2 [1.5]      1 [1.0]      1 [2.0]      4 [1.5]      2 [3.5]                  
                                                                                                                                    
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: 56348-04         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 07/05/01    
Route: DOSED FEED                                                   CITRAL                                        Time: 14:03:02    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE MALE                             UNTREAT      VEHICLE      500 PPM      1000 PPM     2000 PPM                  
                                                      CONTROL      CONTROL                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
RESPIRATORY SYSTEM - CONT                                                                                                           
      Alveolus, Infiltration Cellular, Histiocyte      1 [3.0]                                                                      
      Bronchiole, Inflammation, Suppurative            1 [1.0]                                                                      
      Serosa, Fibrosis                                 2 [1.0]                                1 [2.0]                               
      Serosa, Fibrosis, Focal                                       1 [1.0]                                                         
      Serosa, Inflammation, Chronic                                 1 [1.0]                                                         
   Nose                                               (50)         (50)         (50)         (50)         (50)                      
      Infiltration Cellular, Mast Cell                 1 [2.0]                                                                      
      Inflammation, Suppurative                                     1 [2.0]      1 [1.0]                                            
      Sinus, Inflammation, Suppurative                 1 [2.0]                                                                      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                             (1)                                                              
      Anterior Chamber, Infiltration Cellular,                                                                                      
           Histiocyte                                               1 [2.0]                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (50)         (50)         (50)         (50)         (50)                      
      Infarct                                          2 [1.0]      8 [1.1]      5 [1.8]      6 [1.3]      3 [2.0]                  
      Infiltration Cellular, Mast Cell                              1 [3.0]                                                         
      Inflammation, Granulomatous                      1 [3.0]                                1 [1.0]                               
      Inflammation, Suppurative                                                               1 [1.0]                               
      Metaplasia, Osseous                              2 [1.0]      3 [1.0]      3 [1.0]                   1 [1.0]                  
      Nephropathy                                     45 [1.1]     46 [1.0]     36 [1.1]     46 [1.0]     38 [1.1]                  
      Artery, Inflammation, Chronic                                              1 [2.0]                                            
      Artery, Inflammation, Suppurative                                                                    1 [3.0]                  
      Capsule, Inflammation, Chronic                                                          1 [1.0]                               
      Papilla, Hemorrhage                              1 [2.0]                                                                      
      Pelvis, Hemorrhage                               1 [2.0]                                                                      
      Renal Tubule, Cyst                               8 [1.5]      4 [2.0]      6 [1.8]      6 [1.3]      4 [1.0]                  
      Renal Tubule, Cytoplasmic Alteration                                       1 [3.0]                                            
      Renal Tubule, Hyperplasia                        2 [1.0]                   1 [1.0]      2 [2.0]      2 [1.0]                  
      Renal Tubule, Mineralization                    45 [1.0]     48 [1.0]     43 [1.0]     50 [1.0]     33 [1.0]                  
   Urinary Bladder                                    (50)         (50)         (49)         (50)         (50)                      
      Inflammation, Chronic                                                      1 [1.0]                                            
      Transitional Epithelium, Cytoplasmic                                                                                          
          Alteration                                                             1 [2.0]                   1 [2.0]                  
      Transitional Epithelium, Hyperplasia                          1 [2.0]                                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   14                                                              
                                                                                                                                   
                             ------------------------------------------------------------                                           
                             ----------              END OF REPORT             ----------                                           
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