National Toxicology Program

National Toxicology Program
https://ntp.niehs.nih.gov/go/921

TDMS Study 05110-02 Pathology Tables

NTP Experiment-Test: 05110-02         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NAPHTHALENE                                        Date: 02/18/00
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:59:46




       Facility:  Battelle Northwest

       Chemical CAS #:  91-20-3

       Lock Date:  01/05/99

       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

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NTP Experiment-Test: 05110-02         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NAPHTHALENE                                        Date: 02/18/00  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:59:46  
____________________________________________________________________________________________________________________________________

         FISCHER 344 RATS FEMALE                   CONTROL      10 PPM       30 PPM       60 PPM                                    
                                                                                                                                    
____________________________________________________________________________________________________________________________________

DISPOSITION SUMMARY                                                                                                                 


  Animals Initially In Study                          49           49           49           49                                     
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                18           22           16           21                                     
    Natural Death                                      3            6            5            4                                     
  Survivors                                                                                                                         
    Terminal Sacrifice                                28           21           28           24                                     

  Animals Examined Microscopically                    49           49           49           49                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Intestine Large, Cecum                             (49)         (48)         (48)         (48)                                   
      Inflammation, Acute                                                                     1 (2%)                                
   Liver                                              (49)         (49)         (49)         (49)                                   
      Angiectasis                                      2 (4%)       4 (8%)       2 (4%)       1 (2%)                                
      Basophilic Focus                                46 (94%)     44 (90%)     46 (94%)     44 (90%)                               
      Clear Cell Focus                                 7 (14%)     16 (33%)      8 (16%)      6 (12%)                               
      Cyst                                                                                    1 (2%)                                
      Eosinophilic Focus                               1 (2%)                    6 (12%)      2 (4%)                                
      Fatty Change                                    10 (20%)      3 (6%)       2 (4%)       4 (8%)                                
      Hepatodiaphragmatic Nodule                       4 (8%)       1 (2%)       6 (12%)      5 (10%)                               
      Inflammation, Chronic                            2 (4%)                                                                       
      Mixed Cell Focus                                 6 (12%)      6 (12%)      7 (14%)      6 (12%)                               
      Necrosis                                         1 (2%)       1 (2%)       1 (2%)                                             
      Regeneration                                     1 (2%)       2 (4%)       2 (4%)       2 (4%)                                
      Vacuolization Cytoplasmic, Focal                 1 (2%)       1 (2%)                                                          
      Bile Duct, Hyperplasia                           5 (10%)      5 (10%)      5 (10%)      6 (12%)                               
      Centrilobular, Necrosis                         11 (22%)     11 (22%)      7 (14%)      9 (18%)                               
      Hepatocyte, Atrophy                                                        1 (2%)                                             
   Mesentery                                          (13)         (8)          (7)          (5)                                    
      Fat, Hemorrhage                                  1 (8%)                                                                       
      Fat, Inflammation                                             1 (13%)                                                         
      Fat, Necrosis                                   13 (100%)     7 (88%)      6 (86%)      5 (100%)                              
   Pancreas                                           (49)         (49)         (49)         (49)                                   
      Atrophy                                         18 (37%)      9 (18%)     11 (22%)     10 (20%)                               
      Basophilic Focus                                              1 (2%)       1 (2%)                                             
      Hyperplasia                                                   1 (2%)                                                          
      Duct, Cyst                                                    1 (2%)                                                          
   Salivary Glands                                    (49)         (49)         (49)         (49)                                   
      Atrophy                                          1 (2%)                                 2 (4%)                                
      Basophilic Focus                                 1 (2%)                                                                       
   Stomach, Forestomach                               (49)         (49)         (49)         (49)                                   
      Hyperplasia, Squamous                                                                   1 (2%)                                
      Inflammation, Acute                              1 (2%)                                                                       
      Ulcer                                            3 (6%)       2 (4%)       2 (4%)                                             

a  Number of animals examined microscopically at site and number of animals with lesion                                             
NTP Experiment-Test: 05110-02         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NAPHTHALENE                                        Date: 02/18/00  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:59:46  
____________________________________________________________________________________________________________________________________

         FISCHER 344 RATS FEMALE                   CONTROL      10 PPM       30 PPM       60 PPM                                    
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
   Stomach, Glandular                                 (49)         (48)         (49)         (49)                                   
      Hyperplasia                                                                1 (2%)                                             
      Mineralization                                   2 (4%)       2 (4%)                    2 (4%)                                
      Necrosis                                         3 (6%)       2 (4%)       1 (2%)                                             
      Ulcer                                            1 (2%)                    1 (2%)                                             
   Tongue                                             (1)          (1)                       (1)                                    
      Epithelium, Hyperplasia                          1 (100%)                                                                     
   Tooth                                                                        (1)          (1)                                    
      Malformation                                                               1 (100%)     1 (100%)                              
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Heart                                              (49)         (49)         (49)         (49)                                   
      Cardiomyopathy                                  32 (65%)     31 (63%)     31 (63%)     34 (69%)                               
      Atrium, Thrombosis                               2 (4%)       2 (4%)       1 (2%)       1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (49)         (49)         (49)         (49)                                   
      Atrophy                                          2 (4%)                                                                       
      Degeneration, Cystic                             4 (8%)       4 (8%)       3 (6%)       3 (6%)                                
      Hyperplasia                                     23 (47%)     12 (24%)     18 (37%)     24 (49%)                               
      Hypertrophy                                      7 (14%)      4 (8%)      12 (24%)      6 (12%)                               
      Necrosis                                         4 (8%)       2 (4%)                    1 (2%)                                
      Thrombosis                                       1 (2%)                                                                       
      Vacuolization Cytoplasmic                                     2 (4%)                    1 (2%)                                
   Adrenal Medulla                                    (48)         (49)         (49)         (49)                                   
      Hyperplasia                                     10 (21%)      3 (6%)       9 (18%)      5 (10%)                               
      Necrosis                                         2 (4%)       1 (2%)                                                          
      Thrombosis                                       1 (2%)                                                                       
   Islets, Pancreatic                                 (49)         (49)         (49)         (49)                                   
      Hyperplasia                                                                1 (2%)                                             
   Parathyroid Gland                                  (42)         (40)         (41)         (48)                                   
      Hyperplasia                                                                1 (2%)                                             
   Pituitary Gland                                    (49)         (49)         (49)         (48)                                   
      Angiectasis                                      2 (4%)       2 (4%)       3 (6%)       2 (4%)                                
      Cyst                                                                                    1 (2%)                                
      Pars Distalis, Hyperplasia                      24 (49%)     13 (27%)     18 (37%)     15 (31%)                               
   Thyroid Gland                                      (47)         (46)         (48)         (48)                                   
      C-Cell, Hyperplasia                             39 (83%)     37 (80%)     37 (77%)     42 (88%)                               
      Follicular Cell, Hyperplasia                                               1 (2%)                                             
____________________________________________________________________________________________________________________________________

a  Number of animals examined microscopically at site and number of animals with lesion                                             
NTP Experiment-Test: 05110-02         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NAPHTHALENE                                        Date: 02/18/00  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:59:46  
____________________________________________________________________________________________________________________________________

         FISCHER 344 RATS FEMALE                   CONTROL      10 PPM       30 PPM       60 PPM                                    
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Clitoral Gland                                     (49)         (47)         (49)         (48)                                   
      Hyperplasia                                      1 (2%)       2 (4%)       2 (4%)       3 (6%)                                
      Inflammation, Chronic Active                     2 (4%)                    1 (2%)       1 (2%)                                
   Ovary                                              (49)         (49)         (49)         (49)                                   
      Cyst                                             7 (14%)      9 (18%)     11 (22%)      8 (16%)                               
      Inflammation, Granulomatous                      1 (2%)       1 (2%)                    2 (4%)                                
   Uterus                                             (49)         (49)         (49)         (49)                                   
      Cyst                                             1 (2%)                                                                       
   Vagina                                                                       (1)                                                 
      Inflammation, Suppurative                                                  1 (100%)                                           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (49)         (49)         (49)         (49)                                   
      Atrophy                                                                                 1 (2%)                                
      Hyperplasia, Reticulum Cell                      1 (2%)                    1 (2%)                                             
      Myelofibrosis                                    1 (2%)                                                                       
   Lymph Node, Mediastinal                            (40)         (39)         (41)         (31)                                   
      Congestion                                                                 1 (2%)                                             
      Hemorrhage                                                                 1 (2%)                                             
   Spleen                                             (49)         (49)         (49)         (49)                                   
      Fibrosis                                         3 (6%)       3 (6%)       3 (6%)       2 (4%)                                
      Hematopoietic Cell Proliferation                 2 (4%)       4 (8%)       1 (2%)       4 (8%)                                
      Hemorrhage                                                    2 (4%)                    1 (2%)                                
      Metaplasia, Osseous                                                                     1 (2%)                                
      Necrosis                                         2 (4%)       1 (2%)       1 (2%)       1 (2%)                                
   Thymus                                             (46)         (45)         (48)         (41)                                   
      Cyst                                                                       1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (49)         (49)         (49)         (49)                                   
      Galactocele                                      1 (2%)       2 (4%)       1 (2%)       1 (2%)                                
      Hyperplasia, Atypical                                                                   1 (2%)                                
      Inflammation, Chronic Active                     2 (4%)                                                                       
   Skin                                               (49)         (49)         (49)         (49)                                   
      Hyperkeratosis                                                                          1 (2%)                                
      Inflammation, Acute                                                                     2 (4%)                                

a  Number of animals examined microscopically at site and number of animals with lesion                                             
NTP Experiment-Test: 05110-02         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NAPHTHALENE                                        Date: 02/18/00  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:59:46  
____________________________________________________________________________________________________________________________________

         FISCHER 344 RATS FEMALE                   CONTROL      10 PPM       30 PPM       60 PPM                                    
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
INTEGUMENTARY SYSTEM - CONT                                                                                                         
      Inflammation, Chronic Active                     1 (2%)                                                                       
      Epidermis, Hyperplasia                           1 (2%)                                                                       
      Subcutaneous Tissue, Hemorrhage                               1 (2%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (49)         (49)         (49)         (49)                                   
      Osteopetrosis                                   10 (20%)      4 (8%)       7 (14%)      5 (10%)                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (49)         (49)         (49)         (49)                                   
      Angiectasis                                                                1 (2%)                                             
      Degeneration                                     1 (2%)                                                                       
      Thrombosis                                       1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Larynx                                             (49)         (49)         (49)         (49)                                   
      Hyperplasia                                                                             1 (2%)                                
      Metaplasia, Squamous                             2 (4%)                    4 (8%)       1 (2%)                                
   Lung                                               (49)         (49)         (49)         (49)                                   
      Congestion, Chronic                                                        1 (2%)                                             
      Inflammation, Chronic Active                    16 (33%)     15 (31%)     19 (39%)     22 (45%)                               
      Metaplasia, Osseous                                                        1 (2%)                                             
      Alveolar Epithelium, Hyperplasia                 4 (8%)      11 (22%)     11 (22%)      9 (18%)                               
      Alveolus, Infiltration Cellular, Histiocyte     19 (39%)      7 (14%)     11 (22%)     14 (29%)                               
      Bronchiole, Hyperplasia                          1 (2%)       1 (2%)       1 (2%)       1 (2%)                                
   Nose                                               (49)         (49)         (49)         (49)                                   
      Inflammation, Suppurative                        2 (4%)       5 (10%)      5 (10%)      5 (10%)                               
      Thrombosis                                       7 (14%)      4 (8%)       3 (6%)       3 (6%)                                
      Glands, Hyperplasia                                          48 (98%)     48 (98%)     42 (86%)                               
      Glands, Metaplasia, Squamous                                  2 (4%)      20 (41%)     20 (41%)                               
      Goblet Cell, Respiratory Epithelium,                                                                                          
          Hyperplasia                                              16 (33%)     29 (59%)     20 (41%)                               
      Olfactory Epithelium, Atrophy                                49 (100%)    49 (100%)    47 (96%)                               
      Olfactory Epithelium, Degeneration, Hyaline     13 (27%)     46 (94%)     49 (100%)    45 (92%)                               
      Olfactory Epithelium, Hyperplasia, Atypical                  48 (98%)     48 (98%)     43 (88%)                               
      Olfactory Epithelium, Inflammation, Chronic                  47 (96%)     47 (96%)     45 (92%)                               
      Respiratory Epithelium, Degeneration, Hyaline    8 (16%)     33 (67%)     34 (69%)     28 (57%)                               
      Respiratory Epithelium, Hyperplasia                          18 (37%)     22 (45%)     23 (47%)                               
      Respiratory Epithelium, Metaplasia, Squamous                 21 (43%)     17 (35%)     15 (31%)                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    

a  Number of animals examined microscopically at site and number of animals with lesion                                             
NTP Experiment-Test: 05110-02         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NAPHTHALENE                                        Date: 02/18/00  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:59:46  
____________________________________________________________________________________________________________________________________

         FISCHER 344 RATS FEMALE                   CONTROL      10 PPM       30 PPM       60 PPM                                    
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                (48)         (47)         (46)         (48)                                   
      Cataract                                         5 (10%)      2 (4%)       6 (13%)      3 (6%)                                
      Cornea, Infiltration Cellular,                                                                                                
          Polymorphonuclear                            2 (4%)                                                                       
      Retina, Atrophy                                  5 (10%)      2 (4%)       4 (9%)       2 (4%)                                
   Harderian Gland                                                                           (1)                                    
      Inflammation, Chronic                                                                   1 (100%)                              
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (48)         (49)         (49)         (49)                                   
      Cyst                                                          1 (2%)                                                          
      Infarct                                                                    1 (2%)       1 (2%)                                
      Nephropathy                                     41 (85%)     38 (78%)     34 (69%)     31 (63%)                               
      Renal Tubule, Necrosis                           1 (2%)       1 (2%)                                                          
                                                                                                                                    

a  Number of animals examined microscopically at site and number of animals with lesion                                             
NTP Experiment-Test: 05110-02         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NAPHTHALENE                                        Date: 02/18/00  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:59:46  
____________________________________________________________________________________________________________________________________

         FISCHER 344 RATS MALE                     CONTROL      10 PPM       30 PPM       60 PPM                                    
                                                                                                                                    
____________________________________________________________________________________________________________________________________

DISPOSITION SUMMARY                                                                                                                 


  Animals Initially In Study                          49           49           49           49                                     
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                21           22           19           25                                     
    Natural Death                                      4            5            6            3                                     
  Survivors                                                                                                                         
    Terminal Sacrifice                                24           22           23           21                                     
  Other                                                                          1                                                  

  Animals Examined Microscopically                    49           49           48           49                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Liver                                              (49)         (49)         (48)         (49)                                   
      Angiectasis                                      1 (2%)       1 (2%)       1 (2%)                                             
      Basophilic Focus                                34 (69%)     31 (63%)     28 (58%)     32 (65%)                               
      Clear Cell Focus                                14 (29%)     14 (29%)     14 (29%)     11 (22%)                               
      Degeneration, Cystic                             3 (6%)       3 (6%)       2 (4%)       2 (4%)                                
      Eosinophilic Focus                               3 (6%)       2 (4%)       1 (2%)       2 (4%)                                
      Fatty Change                                     2 (4%)       2 (4%)       4 (8%)       5 (10%)                               
      Hepatodiaphragmatic Nodule                       1 (2%)       3 (6%)       2 (4%)       2 (4%)                                
      Inflammation, Granulomatous                                   1 (2%)                                                          
      Mixed Cell Focus                                 3 (6%)       2 (4%)       2 (4%)       2 (4%)                                
      Necrosis                                                                   1 (2%)                                             
      Regeneration                                     1 (2%)       2 (4%)       1 (2%)       1 (2%)                                
      Syncytial Alteration                                                                    1 (2%)                                
      Tension Lipidosis                                                          1 (2%)                                             
      Artery, Inflammation                             1 (2%)                                                                       
      Bile Duct, Hyperplasia                          35 (71%)     32 (65%)     28 (58%)     21 (43%)                               
      Centrilobular, Necrosis                         13 (27%)     11 (22%)      7 (15%)      4 (8%)                                
   Mesentery                                          (13)         (6)          (9)          (8)                                    
      Artery, Inflammation, Chronic Active             3 (23%)                                1 (13%)                               
      Artery, Mineralization                                                     1 (11%)                                            
      Fat, Hemorrhage                                               1 (17%)                                                         
      Fat, Inflammation                                             1 (17%)                                                         
      Fat, Necrosis                                   10 (77%)      4 (67%)      8 (89%)      6 (75%)                               
   Pancreas                                           (49)         (49)         (48)         (49)                                   
      Atrophy                                         19 (39%)     17 (35%)     17 (35%)     14 (29%)                               
      Basophilic Focus                                              1 (2%)       1 (2%)       1 (2%)                                
      Hyperplasia                                                   3 (6%)       2 (4%)       1 (2%)                                
      Artery, Inflammation                             1 (2%)                    1 (2%)                                             
      Duct, Cyst                                                                              1 (2%)                                
   Salivary Glands                                    (49)         (49)         (47)         (49)                                   
      Atrophy                                                       1 (2%)                                                          
      Metaplasia, Squamous                             1 (2%)                                                                       
      Necrosis                                         1 (2%)                                                                       

a  Number of animals examined microscopically at site and number of animals with lesion                                             
NTP Experiment-Test: 05110-02         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NAPHTHALENE                                        Date: 02/18/00  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:59:46  
____________________________________________________________________________________________________________________________________

         FISCHER 344 RATS MALE                     CONTROL      10 PPM       30 PPM       60 PPM                                    
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
   Stomach, Forestomach                               (49)         (49)         (48)         (49)                                   
      Diverticulum                                     1 (2%)                                                                       
      Hyperplasia, Squamous                            2 (4%)       2 (4%)       2 (4%)       1 (2%)                                
      Inflammation, Acute                                                        1 (2%)                                             
      Necrosis                                                                                1 (2%)                                
      Ulcer                                            1 (2%)       6 (12%)      3 (6%)       2 (4%)                                
   Stomach, Glandular                                 (49)         (49)         (48)         (49)                                   
      Inflammation, Acute                                                        1 (2%)                                             
      Mineralization                                                2 (4%)       1 (2%)                                             
      Necrosis                                         7 (14%)      2 (4%)       2 (4%)       3 (6%)                                
      Ulcer                                                         1 (2%)                    1 (2%)                                
      Artery, Inflammation                             1 (2%)                                                                       
   Tongue                                                          (1)          (1)                                                 
      Epithelium, Hyperplasia                                                    1 (100%)                                           
   Tooth                                              (1)          (2)          (4)          (2)                                    
      Inflammation, Chronic Active                     1 (100%)     1 (50%)      4 (100%)                                           
      Malformation                                                  1 (50%)                   2 (100%)                              
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Heart                                              (49)         (49)         (48)         (49)                                   
      Cardiomyopathy                                  42 (86%)     44 (90%)     37 (77%)     42 (86%)                               
      Necrosis                                         1 (2%)                                                                       
      Atrium, Thrombosis                               5 (10%)      2 (4%)       3 (6%)       2 (4%)                                
      Valve, Thrombosis, Chronic                                    1 (2%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (49)         (49)         (48)         (49)                                   
      Angiectasis                                      1 (2%)       1 (2%)                                                          
      Degeneration, Cystic                                          2 (4%)       1 (2%)       1 (2%)                                
      Hyperplasia                                     30 (61%)     28 (57%)     23 (48%)     36 (73%)                               
      Hypertrophy                                      7 (14%)      6 (12%)      9 (19%)      4 (8%)                                
      Necrosis                                                      1 (2%)       2 (4%)       1 (2%)                                
      Vacuolization Cytoplasmic                        1 (2%)       1 (2%)       3 (6%)                                             
   Adrenal Medulla                                    (49)         (49)         (47)         (49)                                   
      Hyperplasia                                     26 (53%)     13 (27%)     23 (49%)     12 (24%)                               
      Necrosis                                                      1 (2%)                                                          
   Islets, Pancreatic                                 (49)         (49)         (48)         (49)                                   
      Hyperplasia                                                   1 (2%)       2 (4%)       1 (2%)                                
   Pituitary Gland                                    (49)         (49)         (47)         (49)                                   
      Angiectasis                                      1 (2%)                                 1 (2%)                                
      Cyst                                                          1 (2%)                    1 (2%)                                
      Pars Distalis, Hyperplasia                      11 (22%)     12 (24%)     10 (21%)     15 (31%)                               
   Thyroid Gland                                      (46)         (47)         (45)         (47)                                   

a  Number of animals examined microscopically at site and number of animals with lesion                                             
NTP Experiment-Test: 05110-02         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NAPHTHALENE                                        Date: 02/18/00  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:59:46  
____________________________________________________________________________________________________________________________________

         FISCHER 344 RATS MALE                     CONTROL      10 PPM       30 PPM       60 PPM                                    
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ENDOCRINE SYSTEM - CONT                                                                                                             
      C-Cell, Hyperplasia                             32 (70%)     36 (77%)     31 (69%)     33 (70%)                               
      Follicular Cell, Hyperplasia                     2 (4%)                    3 (7%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   Peritoneum                                                                   (1)                                                 
      Inflammation, Suppurative                                                  1 (100%)                                           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Epididymis                                         (49)         (49)         (48)         (49)                                   
      Angiectasis                                                   1 (2%)                                                          
      Granuloma Sperm                                               1 (2%)                                                          
   Preputial Gland                                    (48)         (49)         (47)         (49)                                   
      Cyst                                                                       1 (2%)       1 (2%)                                
      Hyperplasia, Squamous                            1 (2%)                                                                       
      Inflammation, Chronic Active                     2 (4%)                    2 (4%)       2 (4%)                                
   Prostate                                           (49)         (49)         (48)         (49)                                   
      Hyperplasia                                     11 (22%)      8 (16%)     16 (33%)      8 (16%)                               
      Inflammation, Chronic Active                     3 (6%)       2 (4%)       3 (6%)       2 (4%)                                
      Epithelium, Hyperplasia                          1 (2%)                                                                       
   Seminal Vesicle                                    (47)         (49)         (47)         (47)                                   
      Inflammation, Chronic Active                                                            1 (2%)                                
   Testes                                             (49)         (49)         (48)         (49)                                   
      Atrophy                                          2 (4%)       4 (8%)       2 (4%)       4 (8%)                                
      Artery, Inflammation, Chronic Active                          2 (4%)                    2 (4%)                                
      Interstitial Cell, Hyperplasia                   5 (10%)      9 (18%)      2 (4%)      11 (22%)                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Lymph Node                                         (3)          (3)          (8)          (4)                                    
      Iliac, Hemorrhage                                1 (33%)                                                                      
   Lymph Node, Mandibular                             (40)         (45)         (46)         (44)                                   
      Infiltration Cellular, Plasma Cell               1 (3%)       1 (2%)       1 (2%)       1 (2%)                                
      Infiltration Cellular, Polymorphonuclear         1 (3%)                                                                       
   Spleen                                             (49)         (49)         (48)         (49)                                   
      Fibrosis                                         7 (14%)     12 (24%)      6 (13%)      6 (12%)                               
      Hematopoietic Cell Proliferation                 4 (8%)       3 (6%)       1 (2%)       4 (8%)                                
      Hemorrhage                                       3 (6%)       1 (2%)       2 (4%)       2 (4%)                                
      Necrosis                                         3 (6%)       2 (4%)       1 (2%)       2 (4%)                                
      Thrombosis                                       1 (2%)                                 1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    

a  Number of animals examined microscopically at site and number of animals with lesion                                             
NTP Experiment-Test: 05110-02         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NAPHTHALENE                                        Date: 02/18/00  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:59:46  
____________________________________________________________________________________________________________________________________

         FISCHER 344 RATS MALE                     CONTROL      10 PPM       30 PPM       60 PPM                                    
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (21)         (20)         (30)         (28)                                   
      Galactocele                                                                1 (3%)                                             
   Skin                                               (48)         (48)         (48)         (48)                                   
      Cyst Epithelial Inclusion                                                  1 (2%)                                             
      Hyperkeratosis                                   4 (8%)       2 (4%)                    1 (2%)                                
      Hyperplasia, Basal Cell                                                    1 (2%)                                             
      Hyperplasia, Squamous                                                                   1 (2%)                                
      Inflammation, Acute                                           1 (2%)                                                          
      Inflammation, Chronic Active                     4 (8%)       1 (2%)                                                          
      Epithelium, Hyperplasia, Basal Cell              1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (49)         (49)         (48)         (49)                                   
      Osteopetrosis                                                              1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (49)         (49)         (48)         (49)                                   
      Degeneration                                     1 (2%)                    1 (2%)                                             
      Necrosis                                                                   1 (2%)                                             
      Artery, Inflammation                             1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Larynx                                             (49)         (49)         (48)         (49)                                   
      Metaplasia, Squamous                                          1 (2%)       2 (4%)                                             
   Lung                                               (49)         (49)         (48)         (49)                                   
      Cyst, Squamous                                                1 (2%)                                                          
      Foreign Body                                     1 (2%)                                 1 (2%)                                
      Hemorrhage                                       1 (2%)                                                                       
      Inflammation, Chronic Active                     2 (4%)      13 (27%)      6 (13%)     15 (31%)                               
      Inflammation, Granulomatous                      1 (2%)                                 1 (2%)                                
      Inflammation, Suppurative                                     1 (2%)                                                          
      Metaplasia, Osseous                              1 (2%)                                                                       
      Thrombosis                                       1 (2%)       1 (2%)                                                          
      Alveolar Epithelium, Hyperplasia                23 (47%)     12 (24%)      9 (19%)     16 (33%)                               
      Alveolar Epithelium, Metaplasia                  1 (2%)                                                                       
      Alveolus, Infiltration Cellular, Histiocyte     12 (24%)      9 (18%)      6 (13%)     15 (31%)                               
      Bronchiole, Hyperplasia                          1 (2%)       1 (2%)                                                          
   Nose                                               (49)         (49)         (48)         (48)                                   
      Foreign Body                                     1 (2%)                                                                       
      Inflammation, Suppurative                       12 (24%)     18 (37%)     16 (33%)      9 (19%)                               

a  Number of animals examined microscopically at site and number of animals with lesion                                             
NTP Experiment-Test: 05110-02         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NAPHTHALENE                                        Date: 02/18/00  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:59:46  
____________________________________________________________________________________________________________________________________

         FISCHER 344 RATS MALE                     CONTROL      10 PPM       30 PPM       60 PPM                                    
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
RESPIRATORY SYSTEM - CONT                                                                                                           
      Thrombosis                                       6 (12%)      7 (14%)      6 (13%)      3 (6%)                                
      Glands, Hyperplasia                              1 (2%)      49 (100%)    48 (100%)    48 (100%)                              
      Glands, Metaplasia, Squamous                                  3 (6%)      14 (29%)     26 (54%)                               
      Goblet Cell, Respiratory Epithelium,                                                                                          
          Hyperplasia                                              25 (51%)     29 (60%)     26 (54%)                               
      Olfactory Epithelium, Atrophy                    3 (6%)      49 (100%)    48 (100%)    47 (98%)                               
      Olfactory Epithelium, Degeneration, Hyaline      3 (6%)      45 (92%)     40 (83%)     38 (79%)                               
      Olfactory Epithelium, Hyperplasia, Atypical                  48 (98%)     45 (94%)     46 (96%)                               
      Olfactory Epithelium, Inflammation, Chronic                  49 (100%)    48 (100%)    48 (100%)                              
      Respiratory Epithelium, Degeneration, Hyaline                20 (41%)     19 (40%)     19 (40%)                               
      Respiratory Epithelium, Hyperplasia              3 (6%)      21 (43%)     29 (60%)     29 (60%)                               
      Respiratory Epithelium, Metaplasia, Squamous                 15 (31%)     23 (48%)     18 (38%)                               
   Trachea                                            (49)         (49)         (48)         (49)                                   
      Inflammation, Suppurative                                                  1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                (48)         (48)         (48)         (48)                                   
      Cataract                                         4 (8%)       2 (4%)       1 (2%)       3 (6%)                                
      Hemorrhage                                                                              1 (2%)                                
      Inflammation, Suppurative                        1 (2%)                                                                       
      Retina, Atrophy                                  2 (4%)       1 (2%)       1 (2%)       2 (4%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (49)         (49)         (48)         (49)                                   
      Infarct                                          3 (6%)                    1 (2%)       3 (6%)                                
      Inflammation, Suppurative                                                               1 (2%)                                
      Metaplasia, Osseous                                                        1 (2%)                                             
      Nephropathy                                     43 (88%)     44 (90%)     45 (94%)     43 (88%)                               
      Renal Tubule, Hyperplasia                                                  1 (2%)       1 (2%)                                
   Urinary Bladder                                    (48)         (49)         (48)         (49)                                   
      Hemorrhage                                       1 (2%)                                                                       
      Transitional Epithelium, Hyperplasia                                                    1 (2%)                                
                                                                                                                                    

a  Number of animals examined microscopically at site and number of animals with lesion                                             
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                             ----------              END OF REPORT             ----------                                           
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NTP is located at the National Institute of Environmental Health Sciences, part of the National Institutes of Health.