National Toxicology Program

National Toxicology Program
https://ntp.niehs.nih.gov/go/937

TDMS Study 05110-01 Pathology Tables



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


NTP Experiment-Test: 05110-01                                                                                     Report: PEIRPT03
Study Type: CHRONIC                                                                                               Date: 09/14/94
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 02:12:04




       Facility:  Northrop Services, Inc.

       Chemical CAS #:  91-20-3

       Lock Date:  None

       Cage Range:  All

       Reasons For Removal:    All

       Removal Date Range:     All

       Treatment Groups:       Include All
































a  Number of animals examined microscopically at site and number of animals with lesion

                                                             Page   1

NTP Experiment-Test: 05110-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NAPHTHALENE                                        Date: 09/14/94  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 02:12:04  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        CONTROL      10 PPM       30 PPM       30 PPM                                    
                                                                                                                                    
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially In Study                          75           75           75           75                                     
  Scheduled Sacrifice                                  5            7            6            6                                     
  Early Deaths                                                                                                                      
    Dead                                               8            6           10            7                                     
    Moribund                                           2            1            6           10                                     
    Accident                                           1            1                                                               
  Survivors                                                                                                                         
    Terminal Sacrifice                                59           56           51           50                                     
    Dead                                                                         1                                                  
    Accident                                                        1                                                               
  Missing                                                           3            1            2                                     
  Animals Examined Microscopically                    69           65           68           67                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Gallbladder                                        (65)         (2)          (60)         (64)                                   
      Dilatation                                                                              1 (2%)                                
      Infiltration Cellular, Focal, Lymphocyte                                   2 (3%)                                             
      Infiltration Cellular, Multifocal, Lymphocyte                              1 (2%)       1 (2%)                                
      Serosa, Inflammation, Chronic, Multifocal        1 (2%)                                                                       
   Intestine Large, Cecum                             (66)         (1)          (60)         (64)                                   
      Hyperplasia, Focal, Lymphoid                                               1 (2%)       1 (2%)                                
      Serosa, Inflammation, Chronic, Multifocal        1 (2%)                                                                       
   Intestine Large, Colon                             (67)         (2)          (62)         (66)                                   
      Parasite Metazoan                                                          4 (6%)       3 (5%)                                
   Intestine Small, Duodenum                          (66)         (4)          (61)         (63)                                   
      Hyperplasia, Focal, Lymphoid                                  1 (25%)      1 (2%)                                             
   Intestine Small, Ileum                             (66)         (1)          (61)         (63)                                   
      Amyloid Deposition, Multifocal                                                          1 (2%)                                
      Serosa, Inflammation, Chronic, Multifocal        1 (2%)                                                                       
   Intestine Small, Jejunum                           (65)         (1)          (61)         (63)                                   
      Serosa, Inflammation, Chronic, Multifocal        1 (2%)                                                                       
   Liver                                              (68)         (12)         (67)         (67)                                   
      Angiectasis, Focal                                                         1 (1%)       1 (1%)                                
      Basophilic Focus                                 1 (1%)                                                                       
      Clear Cell Focus                                                           1 (1%)                                             
      Cyst                                             1 (1%)                                                                       
      Focal Cellular Change, Focal                                               1 (1%)                                             
      Hematopoietic Cell Proliferation, Focal                                    2 (3%)                                             
      Hematopoietic Cell Proliferation, Multifocal     5 (7%)                    7 (10%)      5 (7%)                                
      Infiltration Cellular, Focal, Lymphocyte         1 (1%)                    5 (7%)       7 (10%)                               
      Infiltration Cellular, Multifocal, Lymphocyte   16 (24%)      1 (8%)      16 (24%)     17 (25%)                               
      Inflammation, Chronic, Multifocal                2 (3%)                                                                       
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    2                                                              
NTP Experiment-Test: 05110-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NAPHTHALENE                                        Date: 09/14/94  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 02:12:04  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        CONTROL      10 PPM       30 PPM       30 PPM                                    
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Mineralization, Focal                                                      1 (1%)       1 (1%)                                
      Necrosis, Focal                                                            1 (1%)       2 (3%)                                
      Necrosis, Multifocal                                          1 (8%)       2 (3%)       1 (1%)                                
      Pigmentation, Focal                              1 (1%)                                 1 (1%)                                
      Bile Duct, Cytoplasmic Alteration, Multifocal                              1 (1%)                                             
      Hepatocyte, Atrophy, Diffuse                                                            1 (1%)                                
   Mesentery                                          (6)                       (3)          (3)                                    
      Infiltration Cellular, Multifocal, Lymphocyte    1 (17%)                                1 (33%)                               
      Infiltration Cellular, Multifocal, Mixed Cell                              1 (33%)                                            
      Inflammation, Chronic, Multifocal                1 (17%)                                                                      
      Inflammation, Focal, Granulomatous               1 (17%)                                                                      
      Fat, Necrosis                                    2 (33%)                   1 (33%)                                            
   Pancreas                                           (69)         (5)          (65)         (67)                                   
      Atrophy, Diffuse                                 2 (3%)                                                                       
      Atrophy, Focal                                                                          1 (1%)                                
      Atrophy, Multifocal                              1 (1%)                    1 (2%)       1 (1%)                                
      Infiltration Cellular, Focal, Lymphocyte         3 (4%)                    3 (5%)       1 (1%)                                
      Infiltration Cellular, Multifocal, Lymphocyte   18 (26%)                  17 (26%)     17 (25%)                               
      Inflammation, Multifocal                         3 (4%)                    1 (2%)       1 (1%)                                
      Vacuolization Cytoplasmic, Multifocal                                      1 (2%)                                             
      Acinus, Hyperplasia, Focal                                                              1 (1%)                                
      Duct, Dilatation                                 1 (1%)                    2 (3%)       1 (1%)                                
   Salivary Glands                                    (68)         (5)          (64)         (67)                                   
      Infiltration Cellular, Focal, Lymphocyte         3 (4%)       1 (20%)      3 (5%)      10 (15%)                               
      Infiltration Cellular, Multifocal, Lymphocyte   40 (59%)                  34 (53%)     30 (45%)                               
   Stomach, Forestomach                               (67)         (5)          (67)         (67)                                   
      Hyperkeratosis, Focal                                                                   1 (1%)                                
      Hyperplasia, Focal                                                         1 (1%)       1 (1%)                                
   Stomach, Glandular                                 (67)         (5)          (65)         (67)                                   
      Hemorrhage, Focal                                                                       1 (1%)                                
      Infiltration Cellular, Multifocal, Lymphocyte    1 (1%)                                                                       
      Mucosa, Cyst                                                                            1 (1%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Blood Vessel                                                                 (1)                                                 
      Adventitia, Inflammation, Multifocal                                       1 (100%)                                           
      Media, Hypertrophy, Multifocal                                             1 (100%)                                           
   Heart                                              (69)         (4)          (68)         (67)                                   
      Infiltration Cellular, Focal, Lymphocyte         1 (1%)                                                                       
      Mineralization, Multifocal                                    1 (25%)                                                         
      Myocardium, Inflammation, Chronic, Focal                                   1 (1%)                                             
      Myocardium, Inflammation, Focal, Suppurative                               1 (1%)                                             
      Valve, Pigmentation, Focal                       3 (4%)                    6 (9%)       6 (9%)                                
      Valve, Pigmentation, Multifocal                  7 (10%)                   7 (10%)      7 (10%)                               
____________________________________________________________________________________________________________________________________
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    3                                                              
NTP Experiment-Test: 05110-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NAPHTHALENE                                        Date: 09/14/94  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 02:12:04  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        CONTROL      10 PPM       30 PPM       30 PPM                                    
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Gland                                      (66)         (4)          (67)         (67)                                   
      Capsule, Hyperplasia, Multifocal                66 (100%)     2 (50%)     67 (100%)    66 (99%)                               
      Capsule, Inflammation, Chronic, Multifocal       1 (2%)                                                                       
   Adrenal Gland, Cortex                              (66)         (4)          (67)         (67)                                   
      Accessory Adrenal Cortical Nodule                1 (2%)                                                                       
      Congestion, Multifocal                           1 (2%)                    3 (4%)                                             
      Cyst                                             1 (2%)                                                                       
      Degeneration, Focal                              1 (2%)                    1 (1%)                                             
      Focal Cellular Change                            2 (3%)                                 1 (1%)                                
      Hypertrophy, Focal                                                         1 (1%)                                             
      Pigmentation, Focal                              2 (3%)                                                                       
   Adrenal Gland, Medulla                             (64)         (4)          (66)         (66)                                   
      Congestion, Multifocal                                                     1 (2%)                                             
      Degeneration                                                                            1 (2%)                                
      Hyperplasia                                      1 (2%)                                 1 (2%)                                
   Islets, Pancreatic                                 (69)         (4)          (66)         (67)                                   
      Hyperplasia, Focal                               1 (1%)                                                                       
   Parathyroid Gland                                  (68)                      (66)         (64)                                   
      Cyst, Focal                                      1 (1%)                                 1 (2%)                                
      Degeneration, Focal                                                                     1 (2%)                                
      Infiltration Cellular, Focal, Lymphocyte                                                1 (2%)                                
      Infiltration Cellular, Multifocal, Lymphocyte                                           1 (2%)                                
      Bilateral, Hyperplasia                                                                  1 (2%)                                
   Pituitary Gland                                    (61)         (4)          (50)         (54)                                   
      Cyst, Multifocal                                                                        1 (2%)                                
      Pars Distalis, Angiectasis                       1 (2%)                    2 (4%)                                             
      Pars Distalis, Hyperplasia                       4 (7%)       1 (25%)                   1 (2%)                                
   Thyroid Gland                                      (69)         (4)          (67)         (66)                                   
      Infiltration Cellular, Focal, Lymphocyte                                   1 (1%)       2 (3%)                                
      Inflammation, Acute, Focal                       1 (1%)                    2 (3%)       2 (3%)                                
      Follicle, Dilatation, Focal                      2 (3%)                    2 (3%)       5 (8%)                                
      Follicular Cell, Hyperplasia, Focal              3 (4%)                    2 (3%)       4 (6%)                                
      Follicular Cell, Hyperplasia, Multifocal         1 (1%)                    1 (1%)       1 (2%)                                
      Follicular Cell, Hypertrophy, Multifocal         1 (1%)                                 1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    4                                                              
NTP Experiment-Test: 05110-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NAPHTHALENE                                        Date: 09/14/94  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 02:12:04  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        CONTROL      10 PPM       30 PPM       30 PPM                                    
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Ovary                                              (69)         (14)         (66)         (65)                                   
      Cyst                                            11 (16%)      9 (64%)     16 (24%)     11 (17%)                               
      Cyst, Multifocal                                 1 (1%)       1 (7%)       1 (2%)       2 (3%)                                
      Giant Cell, Multiple                                                                    1 (2%)                                
      Hematocyst, Focal                                             2 (14%)      2 (3%)       2 (3%)                                
      Infiltration Cellular, Histiocyte                                                       1 (2%)                                
      Inflammation, Multifocal, Suppurative                                      1 (2%)                                             
      Metaplasia, Focal, Osseous                                                 1 (2%)                                             
      Mineralization, Multifocal                                                              1 (2%)                                
      Pigmentation                                     1 (1%)                                                                       
      Follicle, Hemorrhage, Focal                      3 (4%)                                 1 (2%)                                
      Interstitium, Hyperplasia                        1 (1%)                                                                       
   Oviduct                                            (2)          (1)          (4)          (4)                                    
      Mucosa, Hyperplasia, Cystic                                   1 (100%)                                                        
      Mucosa, Vacuolization Cytoplasmic, Multifocal    1 (50%)                                                                      
   Uterus                                             (69)         (41)         (67)         (66)                                   
      Angiectasis, Multifocal                          1 (1%)       1 (2%)       1 (1%)                                             
      Dilatation                                                    2 (5%)       7 (10%)      6 (9%)                                
      Inflammation, Suppurative                                                  1 (1%)       1 (2%)                                
      Endometrium, Hyperplasia, Cystic                61 (88%)     36 (88%)     49 (73%)     56 (85%)                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Blood                                                                        (1)          (5)                                    
      Leukocytosis                                                               1 (100%)     3 (60%)                               
   Bone Marrow                                        (69)         (4)          (68)         (67)                                   
      Angiectasis                                      1 (1%)                    1 (1%)                                             
      Atrophy                                                                    4 (6%)                                             
      Congestion                                                                 1 (1%)                                             
      Fibrous Osteodystrophy, Focal                                                           1 (1%)                                
      Fibrous Osteodystrophy, Multifocal               1 (1%)                                                                       
      Hyperplasia                                      2 (3%)                    1 (1%)       1 (1%)                                
      Hyperplasia, Lymphoid                            4 (6%)                                                                       
      Hyperplasia, Neutrophil                                                                 1 (1%)                                
      Myelofibrosis                                    2 (3%)                    3 (4%)                                             
      Pigmentation, Focal                                                        1 (1%)                                             
      Pigmentation, Multifocal                                                   1 (1%)                                             
   Lymph Node                                         (69)         (9)          (67)         (67)                                   
      Hyperplasia                                                                             1 (1%)                                
   Lymph Node, Bronchial                              (46)         (1)          (46)         (40)                                   
      Congestion                                                                 1 (2%)                                             
      Hyperplasia, Lymphoid                                                      1 (2%)       2 (5%)                                
      Pigmentation                                     1 (2%)                                                                       
   Lymph Node, Mandibular                             (66)         (6)          (62)         (65)                                   
      Edema                                            1 (2%)                                                                       
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    5                                                              
NTP Experiment-Test: 05110-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NAPHTHALENE                                        Date: 09/14/94  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 02:12:04  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        CONTROL      10 PPM       30 PPM       30 PPM                                    
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
HEMATOPOIETIC SYSTEM - CONT                                                                                                         
      Erythrophagocytosis                                                        1 (2%)                                             
      Hemorrhage                                                                 1 (2%)       1 (2%)                                
      Hyperplasia, Lymphoid                            2 (3%)       1 (17%)                   4 (6%)                                
      Infiltration Cellular, Histiocyte                                                       1 (2%)                                
      Pigmentation                                    15 (23%)                  12 (19%)     13 (20%)                               
   Lymph Node, Mediastinal                            (60)         (6)          (52)         (57)                                   
      Angiectasis                                      1 (2%)                                                                       
      Erythrophagocytosis                                                        1 (2%)                                             
      Hyperplasia, Lymphoid                            1 (2%)                    1 (2%)       2 (4%)                                
      Infiltration Cellular, Histiocyte                             1 (17%)                                                         
      Pigmentation                                     8 (13%)                   3 (6%)       1 (2%)                                
   Lymph Node, Mesenteric                             (67)         (4)          (60)         (62)                                   
      Erythrophagocytosis                              2 (3%)                    1 (2%)       1 (2%)                                
      Giant Cell, Multifocal                          17 (25%)                  16 (27%)      8 (13%)                               
      Hemorrhage                                       4 (6%)                    2 (3%)       2 (3%)                                
      Hyperplasia, Lymphoid                            1 (1%)                    1 (2%)       1 (2%)                                
      Hyperplasia, Multifocal, Plasma Cell             1 (1%)                                                                       
      Infiltration Cellular, Polymorphonuclear         1 (1%)                                                                       
   Spleen                                             (67)         (13)         (67)         (67)                                   
      Angiectasis, Multifocal                                                    1 (1%)                                             
      Congestion                                                                 1 (1%)                                             
      Hematopoietic Cell Proliferation                 4 (6%)       3 (23%)      7 (10%)     10 (15%)                               
      Hyperplasia, Lymphoid                            9 (13%)      3 (23%)      6 (9%)      12 (18%)                               
      Hyperplasia, Neutrophil                                                                 1 (1%)                                
      Hyperplasia, Plasma Cell                         1 (1%)                                 1 (1%)                                
      Infiltration Cellular, Histiocyte                             1 (8%)                                                          
      Capsule, Inflammation, Chronic, Multifocal       1 (1%)                                                                       
   Thymus                                             (64)         (3)          (60)         (59)                                   
      Angiectasis                                      1 (2%)                                                                       
      Cyst, Multiple                                   1 (2%)                                                                       
      Depletion Lymphoid                                                         1 (2%)                                             
      Hyperplasia, Lymphoid                            1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (69)         (5)          (66)         (66)                                   
      Hyperplasia, Focal                               2 (3%)                                                                       
      Infiltration Cellular, Focal, Lymphocyte                                   1 (2%)       1 (2%)                                
      Infiltration Cellular, Multifocal, Lymphocyte    1 (1%)                    1 (2%)       2 (3%)                                
      Duct, Galactocele, Multifocal                                              1 (2%)                                             
   Skin                                               (69)         (6)          (67)         (67)                                   
      Acanthosis, Multifocal                                                                  1 (1%)                                
      Inflammation, Focal                                                                     1 (1%)                                
      Subcutaneous Tissue, Infiltration Cellular,                                                                                   
           Multifocal, Lymphocyte                      1 (1%)                                                                       
      Subcutaneous Tissue, Infiltration Cellular,                                                                                   
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    6                                                              
NTP Experiment-Test: 05110-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NAPHTHALENE                                        Date: 09/14/94  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 02:12:04  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        CONTROL      10 PPM       30 PPM       30 PPM                                    
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
INTEGUMENTARY SYSTEM - CONT                                                                                                         
           Multifocal, Polymorphonuclear                                                      1 (1%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (69)         (4)          (68)         (67)                                   
      Fibrous Osteodystrophy, Focal                    3 (4%)                    4 (6%)       6 (9%)                                
      Fibrous Osteodystrophy, Multifocal               7 (10%)                  12 (18%)     11 (16%)                               
      Hyperplasia, Multifocal                                                    1 (1%)                                             
      Metaplasia, Cartilagenous, Focal                                           1 (1%)                                             
   Skeletal Muscle                                                              (3)          (3)                                    
      Head, Hemorrhage, Multifocal                                               1 (33%)                                            
      Hindlimb, Infiltration Cellular, Focal,                                                                                       
          Lymphocyte                                                                          1 (33%)                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (69)         (4)          (68)         (67)                                   
      Fibrosis, Multifocal                                                       1 (1%)                                             
      Hemorrhage, Multifocal                                                     1 (1%)       2 (3%)                                
      Metaplasia, Focal, Osseous                       1 (1%)                                                                       
      Mineralization, Focal                            3 (4%)       1 (25%)     11 (16%)      3 (4%)                                
      Mineralization, Multifocal                      34 (49%)                   8 (12%)     21 (31%)                               
      Cerebrum, Necrosis, Focal                                                  1 (1%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Lung                                               (69)         (65)         (68)         (67)                                   
      Congestion                                       2 (3%)       1 (2%)       1 (1%)                                             
      Hemorrhage                                       1 (1%)       1 (2%)       1 (1%)                                             
      Infiltration Cellular, Lymphocyte               11 (16%)     21 (32%)     20 (29%)     26 (39%)                               
      Infiltration Cellular, Histiocyte                1 (1%)       5 (8%)       2 (3%)       2 (3%)                                
      Inflammation                                     3 (4%)      13 (20%)     34 (50%)     18 (27%)                               
      Inflammation, Granulomatous                                  38 (58%)     14 (21%)     28 (42%)                               
      Metaplasia, Focal, Osseous                                                 1 (1%)                                             
      Alveolar Epithelium, Hyperplasia                 3 (4%)       6 (9%)       5 (7%)       7 (10%)                               
      Glands, Inflammation                             1 (1%)       3 (5%)       7 (10%)      8 (12%)                               
   Nose                                               (69)         (65)         (68)         (67)                                   
      Hemorrhage                                       1 (1%)                    2 (3%)       1 (1%)                                
      Infiltration Cellular, Multifocal, Lymphocyte    1 (1%)                                                                       
      Inflammation                                     1 (1%)      65 (100%)    68 (100%)    67 (100%)                              
      Olfactory Epithelium, Metaplasia                             65 (100%)    68 (100%)    67 (100%)                              
      Respiratory Epithelium, Hyperplasia                          65 (100%)    68 (100%)    67 (100%)                              
   Trachea                                            (69)         (4)          (68)         (66)                                   
      Glands, Dilatation, Multifocal                                                          1 (2%)                                
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    7                                                              
NTP Experiment-Test: 05110-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NAPHTHALENE                                        Date: 09/14/94  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 02:12:04  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        CONTROL      10 PPM       30 PPM       30 PPM                                    
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
RESPIRATORY SYSTEM - CONT                                                                                                           
      Glands, Inflammation, Multifocal, Suppurative    1 (1%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                (2)          (6)          (2)          (4)                                    
      Degeneration                                                  3 (50%)      1 (50%)                                            
      Inflammation                                                                            1 (25%)                               
      Mineralization                                                             1 (50%)                                            
      Pigmentation                                     1 (50%)                                1 (25%)                               
      Bilateral, Lens, Cataract                        1 (50%)                                                                      
      Cornea, Degeneration                             1 (50%)                                                                      
      Lens, Cataract                                                2 (33%)      1 (50%)      2 (50%)                               
      Optic Nerve, Degeneration                        1 (50%)                                                                      
      Retina, Atrophy                                  1 (50%)                                1 (25%)                               
   Harderian Gland                                    (1)          (2)          (1)          (1)                                    
      Infiltration Cellular, Multifocal, Lymphocyte    1 (100%)                                                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (69)         (7)          (67)         (67)                                   
      Congestion, Multifocal                           1 (1%)                                                                       
      Fibrosis, Focal                                                            1 (1%)                                             
      Hemorrhage, Multifocal                                                     1 (1%)                                             
      Infarct, Focal                                   1 (1%)                    1 (1%)                                             
      Infiltration Cellular, Focal, Lymphocyte         2 (3%)                    7 (10%)      1 (1%)                                
      Infiltration Cellular, Multifocal, Lymphocyte   45 (65%)      1 (14%)     40 (60%)     42 (63%)                               
      Inflammation, Acute, Focal                                    1 (14%)                                                         
      Metaplasia, Focal, Osseous                       1 (1%)                                                                       
      Nephropathy                                      3 (4%)       1 (14%)      4 (6%)       4 (6%)                                
      Capsule, Inflammation, Chronic, Multifocal       1 (1%)                                                                       
      Glomerulus, Amyloid Deposition, Multifocal                                              1 (1%)                                
      Renal Tubule, Hyperplasia, Focal                                                        1 (1%)                                
      Renal Tubule, Mineralization, Multifocal                      1 (14%)                                                         
   Urinary Bladder                                    (67)         (1)          (62)         (63)                                   
      Dilatation                                                                 1 (2%)       1 (2%)                                
      Infiltration Cellular, Focal, Lymphocyte         4 (6%)                    6 (10%)      5 (8%)                                
      Infiltration Cellular, Multifocal, Lymphocyte   47 (70%)                  42 (68%)     37 (59%)                               
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    8                                                              
NTP Experiment-Test: 05110-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NAPHTHALENE                                        Date: 09/14/94  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 02:12:04  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          CONTROL      10 PPM       30 PPM       30 PPM                                    
                                                                                                                                    
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially In Study                          75           75           75           75                                     
  Scheduled Sacrifice                                  5            5            6            7                                     
  Early Deaths                                                                                                                      
    Moribund                                          13            7            3            5                                     
    Dead                                              31           10            2            5                                     
    Accident                                                                     2                                                  
  Survivors                                                                                                                         
    Dead                                                            1            1                                                  
    Terminal Sacrifice                                26           50           59           58                                     
    Accident                                                        1                                                               
  Missing                                                           1            2                                                  
  Animals Examined Microscopically                    70           69           67           68                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Gallbladder                                        (57)         (7)          (61)         (65)                                   
      Dilatation                                                    1 (14%)                                                         
      Hemorrhage, Focal                                                                       1 (2%)                                
      Epithelium, Hyperplasia, Focal, Papillary                                  1 (2%)                                             
   Intestine Large, Cecum                             (56)         (5)          (65)         (65)                                   
      Hyperplasia, Focal, Lymphoid                                               1 (2%)       1 (2%)                                
      Inflammation, Diffuse                            1 (2%)                                                                       
   Intestine Large, Colon                             (56)         (7)          (65)         (68)                                   
      Parasite Metazoan                                                          4 (6%)       3 (4%)                                
   Intestine Large, Rectum                            (58)         (5)          (64)         (66)                                   
      Diverticulum                                     1 (2%)                                                                       
      Hemorrhage, Focal                                                                       1 (2%)                                
      Inflammation, Diffuse                            1 (2%)                                                                       
      Parasite Metazoan                                                          1 (2%)                                             
      Prolapse                                                                                1 (2%)                                
   Intestine Small                                    (57)         (8)          (65)         (66)                                   
      Serosa, Fibrosis                                              1 (13%)                                                         
   Intestine Small, Duodenum                          (49)         (5)          (64)         (66)                                   
      Submucosa, Dilatation, Focal                                               1 (2%)                                             
   Intestine Small, Ileum                             (51)         (6)          (64)         (66)                                   
      Inflammation, Multifocal                         1 (2%)                                                                       
   Intestine Small, Jejunum                           (51)         (5)          (64)         (66)                                   
      Hyperplasia, Focal, Lymphoid                                                            2 (3%)                                
   Liver                                              (70)         (33)         (67)         (68)                                   
      Basophilic Focus                                 2 (3%)                    5 (7%)                                             
      Basophilic Focus, Multifocal                                               1 (1%)                                             
      Clear Cell Focus                                                           1 (1%)       2 (3%)                                
      Clear Cell Focus, Multifocal                                                            1 (1%)                                
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    9                                                              
NTP Experiment-Test: 05110-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NAPHTHALENE                                        Date: 09/14/94  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 02:12:04  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          CONTROL      10 PPM       30 PPM       30 PPM                                    
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Cyst, Focal                                                                             1 (1%)                                
      Cytoplasmic Alteration, Focal                                                           1 (1%)                                
      Degeneration, Focal                                           1 (3%)                    1 (1%)                                
      Eosinophilic Focus                                                                      1 (1%)                                
      Fatty Change, Focal                              2 (3%)                                                                       
      Fibrosis, Focal                                                            1 (1%)                                             
      Hematopoietic Cell Proliferation, Focal          1 (1%)                    2 (3%)       2 (3%)                                
      Hematopoietic Cell Proliferation, Multifocal     1 (1%)                    1 (1%)       1 (1%)                                
      Hematopoietic Cell Proliferation Granulocytic    1 (1%)                                                                       
      Hemorrhage, Focal                                                                       1 (1%)                                
      Infarct, Focal                                                                          1 (1%)                                
      Infiltration Cellular, Focal, Lymphocyte                                   1 (1%)       2 (3%)                                
      Infiltration Cellular, Multifocal, Lymphocyte                              3 (4%)       1 (1%)                                
      Mineralization, Focal                                                      1 (1%)                                             
      Mixed Cell Focus                                                           2 (3%)       1 (1%)                                
      Necrosis, Focal                                               2 (6%)                                                          
      Necrosis, Multifocal                             4 (6%)       2 (6%)                    1 (1%)                                
      Thrombosis, Multifocal                                                                  1 (1%)                                
      Hepatocyte, Cytomegaly, Focal                                                           1 (1%)                                
      Serosa, Fibrosis                                              1 (3%)                                                          
      Sinusoid, Ectasia, Focal                         1 (1%)                                 1 (1%)                                
   Mesentery                                          (1)                                    (1)                                    
      Fat, Necrosis, Focal                             1 (100%)                                                                     
   Pancreas                                           (67)         (10)         (66)         (68)                                   
      Atrophy                                          3 (4%)                    1 (2%)       4 (6%)                                
      Infiltration Cellular, Focal, Lymphocyte         3 (4%)                    1 (2%)       1 (1%)                                
      Infiltration Cellular, Multifocal, Lymphocyte    3 (4%)                    3 (5%)       3 (4%)                                
      Infiltration Cellular, Polymorphonuclear         1 (1%)                                                                       
      Inflammation, Chronic Active, Diffuse                         1 (10%)                                                         
      Inflammation, Focal                                                        1 (2%)       1 (1%)                                
   Salivary Glands                                    (69)         (11)         (67)         (68)                                   
      Atrophy, Multifocal                                                                     1 (1%)                                
      Infiltration Cellular, Focal, Lymphocyte         1 (1%)                    8 (12%)      4 (6%)                                
      Infiltration Cellular, Multifocal, Lymphocyte   13 (19%)      1 (9%)      14 (21%)     16 (24%)                               
      Infiltration Cellular, Polymorphonuclear         1 (1%)                                                                       
   Stomach, Forestomach                               (63)         (10)         (65)         (68)                                   
      Hyperplasia, Focal                                                         1 (2%)       1 (1%)                                
      Inflammation, Focal                              1 (2%)                                                                       
   Stomach, Glandular                                 (62)         (10)         (65)         (68)                                   
      Cyst, Focal                                                                             1 (1%)                                
      Infiltration Cellular, Polymorphonuclear         1 (2%)                                                                       
      Inflammation, Acute, Focal                       1 (2%)                    1 (2%)                                             
      Mineralization, Focal                                                      1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   10                                                              
NTP Experiment-Test: 05110-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NAPHTHALENE                                        Date: 09/14/94  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 02:12:04  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          CONTROL      10 PPM       30 PPM       30 PPM                                    
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Heart                                              (70)         (10)         (67)         (68)                                   
      Infiltration Cellular, Polymorphonuclear         1 (1%)                                                                       
      Myocardium, Inflammation, Multifocal             1 (1%)                                 1 (1%)                                
      Valve, Pigmentation, Focal                       5 (7%)                    7 (10%)      5 (7%)                                
      Valve, Pigmentation, Multifocal                  4 (6%)                    3 (4%)       3 (4%)                                
      Ventricle, Thrombosis, Focal                                                            1 (1%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Gland                                      (66)         (11)         (65)         (68)                                   
      Capsule, Hyperplasia, Focal                                                3 (5%)       2 (3%)                                
      Capsule, Hyperplasia, Multifocal                45 (68%)      2 (18%)     49 (75%)     49 (72%)                               
   Adrenal Gland, Cortex                              (66)         (9)          (65)         (68)                                   
      Atrophy, Focal                                   1 (2%)                                                                       
      Atypia Cellular, Focal                                                                  1 (1%)                                
      Clear Cell Focus                                 1 (2%)                                                                       
      Cyst                                                                       1 (2%)                                             
      Focal Cellular Change                            1 (2%)                    3 (5%)                                             
      Giant Cell, Multifocal                                                                  1 (1%)                                
      Hyperplasia, Focal                                                                      1 (1%)                                
      Hypertrophy, Focal                               2 (3%)                    4 (6%)       1 (1%)                                
   Adrenal Gland, Medulla                             (66)         (11)         (64)         (66)                                   
      Hyperplasia                                      1 (2%)       1 (9%)                                                          
   Islets, Pancreatic                                 (67)         (9)          (66)         (68)                                   
      Infiltration Cellular, Focal,                                                                                                 
          Polymorphonuclear                                                      1 (2%)                                             
      Infiltration Cellular, Polymorphonuclear         1 (1%)                                                                       
   Parathyroid Gland                                  (64)         (6)          (62)         (66)                                   
      Cyst, Focal                                      1 (2%)                    4 (6%)       2 (3%)                                
      Ectopic Tissue                                                                          1 (2%)                                
   Pituitary Gland                                    (52)         (5)          (58)         (55)                                   
      Cyst                                                                       1 (2%)                                             
      Pars Distalis, Congestion                        1 (2%)                                                                       
   Thyroid Gland                                      (67)         (8)          (66)         (68)                                   
      Cyst                                                                       1 (2%)                                             
      Infiltration Cellular, Focal, Lymphocyte                                                1 (1%)                                
      C-Cell, Hyperplasia                              1 (1%)                                                                       
      Follicle, Dilatation, Focal                                                             3 (4%)                                
      Follicular Cell, Hyperplasia, Focal              1 (1%)                    1 (2%)       2 (3%)                                
____________________________________________________________________________________________________________________________________
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   11                                                              
NTP Experiment-Test: 05110-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NAPHTHALENE                                        Date: 09/14/94  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 02:12:04  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          CONTROL      10 PPM       30 PPM       30 PPM                                    
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Ductus Deferens                                                 (1)                                                              
      Serosa, Inflammation, Chronic                                 1 (100%)                                                        
   Epididymis                                         (69)         (11)         (67)         (68)                                   
      Granuloma Sperm                                                            2 (3%)       1 (1%)                                
      Infiltration Cellular, Focal, Lymphocyte                                   1 (1%)                                             
      Infiltration Cellular, Polymorphonuclear         1 (1%)                                                                       
      Inflammation, Focal                                                                     1 (1%)                                
      Spermatocele, Focal                              1 (1%)                                 1 (1%)                                
      Duct, Dilatation, Focal                                                    2 (3%)                                             
      Serosa, Inflammation, Chronic                                 1 (9%)                                                          
   Penis                                              (2)          (2)                       (1)                                    
      Inflammation, Multifocal                         1 (50%)                                                                      
   Preputial Gland                                    (4)          (1)                       (3)                                    
      Hyperplasia                                                                             1 (33%)                               
      Inflammation                                     1 (25%)                                1 (33%)                               
      Duct, Dilatation                                 3 (75%)      1 (100%)                  1 (33%)                               
   Prostate                                           (65)         (11)         (67)         (66)                                   
      Infiltration Cellular, Lymphocyte                1 (2%)       1 (9%)                    1 (2%)                                
      Infiltration Cellular, Polymorphonuclear         1 (2%)                                                                       
      Inflammation, Acute                              8 (12%)      2 (18%)                   1 (2%)                                
      Serosa, Inflammation, Chronic                                 1 (9%)                                                          
   Seminal Vesicle                                    (66)         (16)         (67)         (68)                                   
      Dilatation                                       3 (5%)       2 (13%)                   1 (1%)                                
      Inflammation, Focal                              2 (3%)                                 1 (1%)                                
      Serosa, Inflammation, Chronic                                 2 (13%)                                                         
   Testes                                             (69)         (12)         (67)         (68)                                   
      Angiectasis, Focal                                                         1 (1%)                                             
      Atrophy                                                       1 (8%)       1 (1%)       2 (3%)                                
      Mineralization, Focal                            4 (6%)                    2 (3%)       4 (6%)                                
      Thrombosis, Focal                                                          1 (1%)                                             
      Bilateral, Atrophy                               1 (1%)                                 1 (1%)                                
      Interstitial Cell, Hyperplasia, Multifocal                                 1 (1%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Blood                                              (3)                                    (1)                                    
      Leukocytosis                                     3 (100%)                               1 (100%)                              
   Bone Marrow                                        (70)         (10)         (67)         (68)                                   
      Angiectasis, Focal                                                         1 (1%)                                             
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   12                                                              
NTP Experiment-Test: 05110-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NAPHTHALENE                                        Date: 09/14/94  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 02:12:04  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          CONTROL      10 PPM       30 PPM       30 PPM                                    
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
HEMATOPOIETIC SYSTEM - CONT                                                                                                         
      Congestion                                                                              1 (1%)                                
      Hemorrhage, Focal                                                          1 (1%)       1 (1%)                                
      Hyperplasia                                      9 (13%)                   1 (1%)       5 (7%)                                
      Myelofibrosis, Focal                                                       1 (1%)                                             
      Thrombosis                                       1 (1%)                                                                       
      Myeloid Cell, Hyperplasia                        1 (1%)                                                                       
   Lymph Node, Bronchial                              (38)         (5)          (57)         (43)                                   
      Giant Cell, Multifocal                                                     2 (4%)       1 (2%)                                
      Hyperplasia, Lymphoid                            1 (3%)       1 (20%)      2 (4%)                                             
      Infiltration Cellular, Polymorphonuclear         1 (3%)                                                                       
      Pigmentation                                     3 (8%)                    2 (4%)       3 (7%)                                
      Lymphocyte, Necrosis                                          1 (20%)                                                         
   Lymph Node, Mandibular                             (61)         (8)          (59)         (66)                                   
      Angiectasis                                      1 (2%)                                                                       
      Hemorrhage                                       1 (2%)                                                                       
      Hyperplasia, Lymphoid                                                      2 (3%)                                             
      Infiltration Cellular, Polymorphonuclear         1 (2%)                                                                       
      Pigmentation                                    12 (20%)      1 (13%)      5 (8%)      11 (17%)                               
      Lymphocyte, Necrosis, Multifocal                 1 (2%)                                                                       
   Lymph Node, Mediastinal                            (37)         (4)          (43)         (47)                                   
      Hyperplasia, Lymphoid                                         1 (25%)      1 (2%)       1 (2%)                                
      Infiltration Cellular, Polymorphonuclear         1 (3%)                                                                       
      Inflammation, Acute                                           1 (25%)                                                         
      Pigmentation                                     2 (5%)                    1 (2%)       3 (6%)                                
   Lymph Node, Mesenteric                             (57)         (4)          (66)         (63)                                   
      Angiectasis                                      1 (2%)                                                                       
      Erythrophagocytosis                              7 (12%)                  13 (20%)     13 (21%)                               
      Giant Cell, Multifocal                          11 (19%)                  24 (36%)     16 (25%)                               
      Hematopoietic Cell Proliferation Granulocytic    3 (5%)                                                                       
      Hemorrhage                                      12 (21%)                  16 (24%)     13 (21%)                               
      Hyperplasia, Lymphoid                            1 (2%)                    4 (6%)       4 (6%)                                
      Hyperplasia, Plasma Cell                         1 (2%)                                                                       
      Infiltration Cellular, Polymorphonuclear         1 (2%)                                                                       
      Inflammation, Acute                              3 (5%)                                                                       
      Lymphocyte, Necrosis, Multifocal                 1 (2%)                    1 (2%)                                             
   Spleen                                             (69)         (18)         (67)         (68)                                   
      Congestion                                       1 (1%)                                 1 (1%)                                
      Depletion Lymphoid                                            1 (6%)                                                          
      Hematopoietic Cell Proliferation                20 (29%)      5 (28%)                  13 (19%)                               
      Hematopoietic Cell Proliferation Granulocytic    1 (1%)                                                                       
      Hyperplasia, Lymphoid                            1 (1%)       1 (6%)       2 (3%)       5 (7%)                                
      Capsule, Fibrosis                                             1 (6%)                                                          
      Lymphocyte, Necrosis                             2 (3%)                    1 (1%)                                             
   Thymus                                             (47)         (1)          (63)         (63)                                   
      Cyst                                             2 (4%)                    4 (6%)       2 (3%)                                
      Cyst, Multifocal                                                           2 (3%)       2 (3%)                                
      Depletion Lymphoid, Diffuse                      1 (2%)                                                                       
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   13                                                              
NTP Experiment-Test: 05110-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NAPHTHALENE                                        Date: 09/14/94  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 02:12:04  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          CONTROL      10 PPM       30 PPM       30 PPM                                    
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
HEMATOPOIETIC SYSTEM - CONT                                                                                                         
      Ectopic Parathyroid Gland, Focal                                                        1 (2%)                                
      Hyperplasia, Lymphoid, Multifocal                1 (2%)                                                                       
      Epithelial Cell, Cytoplasmic Alteration,                                                                                      
           Focal                                                                              1 (2%)                                
      Thymocyte, Necrosis                              8 (17%)      1 (100%)     1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Skin                                               (69)         (21)         (67)         (68)                                   
      Acanthosis, Focal                                2 (3%)                    1 (1%)                                             
      Cyst Epithelial Inclusion                        1 (1%)                                                                       
      Infiltration Cellular, Polymorphonuclear         1 (1%)                                                                       
      Inflammation, Focal                              5 (7%)       2 (10%)      1 (1%)       2 (3%)                                
      Ulcer                                            4 (6%)       2 (10%)                                                         
      Lymphatic, Dilatation                                                                   2 (3%)                                
      Prepuce, Inflammation, Chronic Active            1 (1%)                                                                       
      Prepuce, Ulcer                                   3 (4%)                                                                       
      Subcutaneous Tissue, Angiectasis                                                        1 (1%)                                
      Subcutaneous Tissue, Edema, Diffuse              1 (1%)                                                                       
      Subcutaneous Tissue, Fibrosis, Multifocal        1 (1%)                                 1 (1%)                                
      Subcutaneous Tissue, Hemorrhage                  1 (1%)                                                                       
      Sweat Gland, Ectasia, Multifocal                                           1 (1%)                                             
      Tail, Inflammation, Multifocal, Necrotizing      1 (1%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (70)         (11)         (67)         (68)                                   
      Vertebra, Developmental Malformation             1 (1%)                                                                       
      Vertebra, Fracture Healed                                     1 (9%)                                                          
   Skeletal Muscle                                                 (4)                                                              
      Inflammation, Chronic                                         3 (75%)                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (70)         (10)         (67)         (68)                                   
      Mineralization, Focal                            1 (1%)                    7 (10%)      4 (6%)                                
      Mineralization, Multifocal                      18 (26%)      1 (10%)     25 (37%)     25 (37%)                               
      Olfactory Lobe, Hemorrhage, Focal                                          1 (1%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   14                                                              
NTP Experiment-Test: 05110-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NAPHTHALENE                                        Date: 09/14/94  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 02:12:04  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          CONTROL      10 PPM       30 PPM       30 PPM                                    
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Larynx                                             (69)         (9)          (64)         (67)                                   
      Infiltration Cellular, Focal, Lymphocyte                                   1 (2%)                                             
      Inflammation, Focal                              1 (1%)                                 2 (3%)                                
      Epithelium, Hyperplasia, Focal                   2 (3%)                                                                       
   Lung                                               (70)         (69)         (67)         (68)                                   
      Congestion                                       9 (13%)      1 (1%)                                                          
      Hemorrhage                                       4 (6%)       3 (4%)       5 (7%)                                             
      Infiltration Cellular, Lymphocyte                3 (4%)                    4 (6%)       4 (6%)                                
      Infiltration Cellular, Polymorphonuclear         1 (1%)                                                                       
      Infiltration Cellular, Histiocyte                1 (1%)      12 (17%)     11 (16%)      5 (7%)                                
      Inflammation                                                 21 (30%)     28 (42%)     28 (41%)                               
      Inflammation, Granulomatous                                  19 (28%)      3 (4%)      12 (18%)                               
      Alveolar Epithelium, Hyperplasia                 2 (3%)       7 (10%)      8 (12%)      4 (6%)                                
      Glands, Dilatation                               2 (3%)                                                                       
      Glands, Inflammation                             7 (10%)     14 (20%)     14 (21%)      8 (12%)                               
      Peribronchiolar, Cyst, Multifocal                1 (1%)                                                                       
   Nose                                               (70)         (69)         (67)         (68)                                   
      Congestion, Multifocal                           3 (4%)                                                                       
      Hemorrhage                                                                 1 (1%)                                             
      Inflammation                                                 67 (97%)     66 (99%)     67 (99%)                               
      Olfactory Epithelium, Metaplasia                             66 (96%)     67 (100%)    67 (99%)                               
      Respiratory Epithelium, Hyperplasia                          66 (96%)     67 (100%)    67 (99%)                               
   Trachea                                            (70)         (9)          (67)         (67)                                   
      Glands, Dilatation                               2 (3%)                    1 (1%)                                             
      Glands, Infiltration Cellular, Focal,                                                                                         
          Lymphocyte                                                             1 (1%)                                             
      Glands, Inflammation, Focal, Suppurative                                   3 (4%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Ear                                                (2)                       (1)          (1)                                    
      Pinna, Inflammation, Focal                       1 (50%)                                                                      
   Eye                                                (3)          (4)          (4)          (3)                                    
      Degeneration                                                  1 (25%)                                                         
      Dysplasia, Multifocal                                                      1 (25%)                                            
      Cornea, Inflammation, Focal                                                             1 (33%)                               
      Iris, Hyperplasia, Multifocal, Melanocyte                                               1 (33%)                               
      Lens, Cataract                                   1 (33%)                                1 (33%)                               
   Harderian Gland                                    (1)          (1)          (1)          (1)                                    
      Cyst, Multiple                                                1 (100%)                                                        
      Inflammation, Chronic                                         1 (100%)                                                        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   15                                                              
NTP Experiment-Test: 05110-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                            NAPHTHALENE                                        Date: 09/14/94  
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 02:12:04  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          CONTROL      10 PPM       30 PPM       30 PPM                                    
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (70)         (16)         (67)         (68)                                   
      Congestion, Multifocal                           1 (1%)                                                                       
      Degeneration                                                  1 (6%)                                                          
      Hydronephrosis                                   1 (1%)       1 (6%)                                                          
      Hypoplasia                                                                              1 (1%)                                
      Infarct, Focal                                   1 (1%)                    1 (1%)       2 (3%)                                
      Infiltration Cellular, Focal, Lymphocyte                                   3 (4%)       3 (4%)                                
      Infiltration Cellular, Multifocal, Lymphocyte   17 (24%)      2 (13%)     30 (45%)     18 (26%)                               
      Infiltration Cellular, Polymorphonuclear         1 (1%)                                                                       
      Inflammation, Acute, Multifocal                  2 (3%)       1 (6%)                    1 (1%)                                
      Nephropathy                                      6 (9%)       2 (13%)      8 (12%)      6 (9%)                                
      Pelvis, Inflammation, Acute                      3 (4%)                                                                       
      Renal Tubule, Dilatation, Focal                  1 (1%)       1 (6%)       3 (4%)                                             
      Renal Tubule, Giant Cell, Focal                                                         1 (1%)                                
      Renal Tubule, Hyperplasia, Focal                 1 (1%)                    3 (4%)                                             
      Renal Tubule, Mineralization, Focal              4 (6%)       1 (6%)       1 (1%)       3 (4%)                                
   Urethra                                            (1)                                                                           
      Distal, Dilatation                               1 (100%)                                                                     
      Epithelium, Necrosis, Multifocal                 1 (100%)                                                                     
   Urinary Bladder                                    (60)         (16)         (66)         (68)                                   
      Dilatation                                       7 (12%)      6 (38%)      3 (5%)       2 (3%)                                
      Hemorrhage                                       2 (3%)                                                                       
      Infiltration Cellular, Focal, Lymphocyte                                                2 (3%)                                
      Infiltration Cellular, Multifocal, Lymphocyte                              6 (9%)       7 (10%)                               
      Infiltration Cellular, Polymorphonuclear         1 (2%)                                                                       
      Inflammation, Acute                              3 (5%)                                                                       
      Inflammation, Chronic Active                     3 (5%)       2 (13%)                   1 (1%)                                
      Serosa, Inflammation, Chronic                                 1 (6%)                                                          
      Transitional Epithelium, Hyperplasia,                                                                                         
          Multifocal                                   1 (2%)                                                                       
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
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NTP is located at the National Institute of Environmental Health Sciences, part of the National Institutes of Health.