National Toxicology Program

National Toxicology Program
https://ntp.niehs.nih.gov/go/4923

TDMS Study 96007-01 Pathology Tables

NTP Experiment-Test: 96007-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                           TOXIC EQUIVALENCY FACTOR EVALUATION (PCB-126)                       Date: 10/01/03
Route: GAVAGE                                                                                                     Time: 11:41:44

                                                         FINAL #3/RATS




       Facility:  Battelle Columbus Laboratory

       Chemical CAS #:  57465-28-8

       Lock Date:  01/09/01

       Cage Range:  All

       Reasons For Removal:    25022 Accidently Killed                 25018 Dosing Accident
                               25019 Moribund Sacrifice                25020 Natural Death
                               25021 Terminal Sacrifice

       Removal Date Range:     All

       Treatment Groups:       Include 001    0 NG/KG
                               Include 003    30 NG/KG
                               Include 004    100     NG/KG
                               Include 005    175     NG/KG
                               Include 006    300     NG/KG
                               Include 007    550     NG/KG
                               Include 008    1000    NG/KG
                               Include 009    1000 NG/KG/STOP

























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

                                                              Page   1


NTP Experiment-Test: 96007-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                           TOXIC EQUIVALENCY FACTOR EVALUATION (PCB-126)                       Date: 10/01/03    
Route: GAVAGE                                                                                                     Time: 11:41:44    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         SPRAGUE-DAWLEY RATS FEMALE                0 NG/KG      30 NG/KG     100          175          300          550             
                                                                             NG/KG        NG/KG        NG/KG        NG/KG           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
DISPOSITION SUMMARY                                                                                                                 
                                                                                                                                    
  Animals Initially In Study                          98           98           98           98           98           98           
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                25           18           21           19           27           18           
    Natural Death                                     10            9            6           11            9           12           
    Accidently Killed                                  1            3                                                               
    Dosing Accident                                    2                                      1            1                        
  Survivors                                                                                                                         
    Natural Death                                                   1            1                                                  
    Terminal Sacrifice                                15           24           25           22           16           23           
                                                                                                                                    
  Animals Examined Microscopically                    53           55           53           53           53           53           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Esophagus                                          (52)         (55)         (53)         (53)         (53)         (52)         
      Hemorrhage                                                                                                        1 (2%)      
      Hyperplasia, Focal, Squamous                                               1 (2%)                                             
      Muscularis, Degeneration                                                                             1 (2%)                   
      Muscularis, Inflammation                         2 (4%)       1 (2%)                    1 (2%)       1 (2%)       2 (4%)      
      Periesophageal Tissue, Inflammation,                                                                                          
        Suppurative                                                                                        1 (2%)                   
   Intestine Large, Colon                             (52)         (55)         (53)         (53)         (53)         (51)         
      Hyperplasia, Adenomatous                                                   1 (2%)                                             
      Inflammation                                                               1 (2%)                                             
      Parasite Metazoan                                             1 (2%)       2 (4%)       1 (2%)                                
   Intestine Large, Rectum                            (52)         (55)         (53)         (52)         (53)         (52)         
      Infiltration Cellular, Lymphocyte                                          1 (2%)                                             
      Inflammation, Chronic Active                                                            1 (2%)                                
      Mineralization                                                1 (2%)                                                          
      Parasite Metazoan                                2 (4%)       2 (4%)       3 (6%)                    1 (2%)                   
      Artery, Inflammation, Chronic Active                                                    1 (2%)                                
   Intestine Large, Cecum                             (52)         (54)         (53)         (51)         (53)         (52)         
      Edema                                                         1 (2%)                                                          
      Hyperplasia, Lymphoid                                                                                1 (2%)                   
      Inflammation                                                  1 (2%)                                                          
   Intestine Small, Duodenum                          (52)         (55)         (52)         (53)         (53)         (51)         
      Erosion                                          1 (2%)                                                                       
   Intestine Small, Ileum                             (52)         (54)         (52)         (51)         (53)         (52)         
      Hyperplasia, Lymphoid                                                                                1 (2%)                   
      Mineralization                                                1 (2%)                                                          
      Epithelium, Hyperplasia                                                                 1 (2%)                                
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page    2                                                              
                                                                                                                                   
NTP Experiment-Test: 96007-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                           TOXIC EQUIVALENCY FACTOR EVALUATION (PCB-126)                       Date: 10/01/03    
Route: GAVAGE                                                                                                     Time: 11:41:44    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         SPRAGUE-DAWLEY RATS FEMALE                0 NG/KG      30 NG/KG     100          175          300          550             
                                                                             NG/KG        NG/KG        NG/KG        NG/KG           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Serosa, Inflammation, Chronic Active             1 (2%)                                                                       
   Liver                                              (53)         (55)         (53)         (53)         (53)         (51)         
      Angiectasis                                      3 (6%)       8 (15%)      4 (8%)       1 (2%)       1 (2%)       2 (4%)      
      Basophilic Focus                                 2 (4%)       4 (7%)       6 (11%)      7 (13%)      2 (4%)       3 (6%)      
      Basophilic Focus, Multiple                       5 (9%)       6 (11%)      4 (8%)       6 (11%)      2 (4%)       2 (4%)      
      Cholangiofibrosis                                             1 (2%)       1 (2%)       1 (2%)       3 (6%)      13 (25%)     
      Clear Cell Focus                                 1 (2%)       1 (2%)                                                          
      Clear Cell Focus, Multiple                       1 (2%)                                                                       
      Cytoplasmic Alteration                                                     1 (2%)       1 (2%)       1 (2%)       1 (2%)      
      Degeneration, Cystic                                                                                 1 (2%)       1 (2%)      
      Eosinophilic Focus                               6 (11%)      4 (7%)       7 (13%)      4 (8%)       2 (4%)       3 (6%)      
      Eosinophilic Focus, Multiple                     5 (9%)       6 (11%)      6 (11%)     17 (32%)     15 (28%)     21 (41%)     
      Fatty Change, Diffuse                            5 (9%)       7 (13%)     14 (26%)     22 (42%)     30 (57%)     45 (88%)     
      Fatty Change, Focal                              2 (4%)       6 (11%)      8 (15%)      6 (11%)      3 (6%)       2 (4%)      
      Hematopoietic Cell Proliferation                                                                                  1 (2%)      
      Hepatocyte, Multinucleate                                     2 (4%)      10 (19%)     14 (26%)     19 (36%)     46 (90%)     
      Hepatodiaphragmatic Nodule                       1 (2%)       1 (2%)                    1 (2%)                                
      Hyperplasia, Nodular                                                                    1 (2%)       3 (6%)      26 (51%)     
      Inflammation                                    36 (68%)     40 (73%)     49 (92%)     50 (94%)     51 (96%)     51 (100%)    
      Mixed Cell Focus                                 4 (8%)       6 (11%)      7 (13%)      3 (6%)                    3 (6%)      
      Mixed Cell Focus, Multiple                      17 (32%)     18 (33%)     25 (47%)     29 (55%)     30 (57%)     26 (51%)     
      Necrosis                                         4 (8%)       2 (4%)       5 (9%)       8 (15%)     11 (21%)     15 (29%)     
      Pigmentation                                     1 (2%)      11 (20%)     41 (77%)     39 (74%)     48 (91%)     51 (100%)    
      Toxic Hepatopathy                                             6 (11%)     22 (42%)     27 (51%)     39 (74%)     51 (100%)    
      Vacuolization Cytoplasmic                                     1 (2%)                                                          
      Artery, Inflammation, Chronic Active                                                    1 (2%)       1 (2%)       1 (2%)      
      Bile Duct, Cyst                                  3 (6%)       6 (11%)                   2 (4%)       3 (6%)       8 (16%)     
      Bile Duct, Fibrosis                              4 (8%)       4 (7%)       3 (6%)       2 (4%)       1 (2%)       4 (8%)      
      Bile Duct, Hyperplasia                           3 (6%)       7 (13%)      7 (13%)     13 (25%)     14 (26%)     45 (88%)     
      Hepatocyte, Degeneration                         3 (6%)       1 (2%)       1 (2%)                    1 (2%)       1 (2%)      
      Hepatocyte, Hypertrophy                                      23 (42%)     32 (60%)     36 (68%)     42 (79%)     50 (98%)     
      Oval Cell, Hyperplasia                                        1 (2%)       6 (11%)      7 (13%)     10 (19%)     38 (75%)     
      Portal, Fibrosis                                                                                     2 (4%)       1 (2%)      
      Serosa, Inflammation                                          1 (2%)                                                          
   Mesentery                                          (1)                       (4)          (2)          (7)          (13)         
      Inflammation, Chronic Active                     1 (100%)                                                                     
      Artery, Inflammation, Chronic Active                                       2 (50%)      2 (100%)     6 (86%)     10 (77%)     
      Fat, Necrosis                                                              1 (25%)                   1 (14%)      1 (8%)      
   Oral Mucosa                                        (1)          (1)          (3)          (4)          (2)          (6)          
      Gingival, Hyperplasia, Squamous                  1 (100%)                  2 (67%)      2 (50%)                   4 (67%)     
   Pancreas                                           (51)         (55)         (53)         (53)         (53)         (52)         
      Basophilic Focus                                              1 (2%)                    1 (2%)                                
      Cyst                                                                                                              1 (2%)      
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page    3                                                              
                                                                                                                                   
NTP Experiment-Test: 96007-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                           TOXIC EQUIVALENCY FACTOR EVALUATION (PCB-126)                       Date: 10/01/03    
Route: GAVAGE                                                                                                     Time: 11:41:44    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         SPRAGUE-DAWLEY RATS FEMALE                0 NG/KG      30 NG/KG     100          175          300          550             
                                                                             NG/KG        NG/KG        NG/KG        NG/KG           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Inflammation, Chronic Active                     5 (10%)      1 (2%)       3 (6%)       4 (8%)       4 (8%)       6 (12%)     
      Acinus, Atrophy                                  5 (10%)      3 (5%)       2 (4%)       7 (13%)      2 (4%)      11 (21%)     
      Acinus, Hyperplasia                                           1 (2%)       1 (2%)       1 (2%)       1 (2%)                   
      Acinus, Vacuolization Cytoplasmic                                          1 (2%)       4 (8%)       9 (17%)     20 (38%)     
      Artery, Inflammation, Chronic Active                          4 (7%)       2 (4%)       4 (8%)       8 (15%)     15 (29%)     
      Artery, Mineralization                                        1 (2%)                                              1 (2%)      
      Duct, Hyperplasia                                                                                                 1 (2%)      
      Duct, Inflammation, Chronic Active                                                                                2 (4%)      
   Salivary Glands                                    (51)         (54)         (53)         (51)         (52)         (51)         
      Atrophy                                                                                 1 (2%)       1 (2%)                   
      Cyst                                                          1 (2%)                                 1 (2%)                   
      Inflammation, Acute                                                                                  1 (2%)                   
      Inflammation, Chronic Active                     1 (2%)                                              1 (2%)                   
   Stomach, Forestomach                               (52)         (55)         (53)         (53)         (53)         (51)         
      Edema                                            1 (2%)                    1 (2%)                    1 (2%)                   
      Erosion                                                       1 (2%)                                                          
      Hyperkeratosis                                                3 (5%)       1 (2%)       1 (2%)       3 (6%)       1 (2%)      
      Hyperplasia, Squamous                            3 (6%)       4 (7%)       6 (11%)      2 (4%)       5 (9%)       6 (12%)     
      Inflammation, Acute                              1 (2%)                                                                       
      Inflammation, Chronic Active                                  1 (2%)       2 (4%)       1 (2%)       1 (2%)                   
      Mineralization                                   1 (2%)                    1 (2%)       1 (2%)                    1 (2%)      
      Necrosis, Focal                                                            1 (2%)                                             
      Ulcer                                            3 (6%)       1 (2%)                    1 (2%)       3 (6%)       2 (4%)      
   Stomach, Glandular                                 (51)         (53)         (53)         (53)         (53)         (51)         
      Erosion                                          1 (2%)       1 (2%)                    1 (2%)                                
      Metaplasia, Focal                                                          1 (2%)                                             
      Mineralization                                   1 (2%)       1 (2%)                    1 (2%)                                
   Tooth                                              (12)         (12)         (10)         (9)          (10)         (9)          
      Peridontal Tissue, Inflammation, Chronic                                                                                      
        Active                                         2 (17%)                                                          1 (11%)     
      Peridontal Tissue, Inflammation, Suppurative    10 (83%)     12 (100%)    10 (100%)     9 (100%)    10 (100%)     8 (89%)     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Blood Vessel                                       (53)         (55)         (53)         (53)         (53)         (53)         
      Aorta, Mineralization                            3 (6%)       1 (2%)       1 (2%)                                 2 (4%)      
   Heart                                              (52)         (54)         (53)         (53)         (53)         (51)         
      Cardiomyopathy                                   9 (17%)     16 (30%)     17 (32%)     16 (30%)     24 (45%)     28 (55%)     
      Degeneration                                     1 (2%)       1 (2%)                                              1 (2%)      
      Inflammation                                                  1 (2%)                                                          
      Mineralization                                   1 (2%)       1 (2%)                                              1 (2%)      
      Thrombosis                                       1 (2%)                                                           1 (2%)      
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page    4                                                              
                                                                                                                                   
NTP Experiment-Test: 96007-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                           TOXIC EQUIVALENCY FACTOR EVALUATION (PCB-126)                       Date: 10/01/03    
Route: GAVAGE                                                                                                     Time: 11:41:44    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         SPRAGUE-DAWLEY RATS FEMALE                0 NG/KG      30 NG/KG     100          175          300          550             
                                                                             NG/KG        NG/KG        NG/KG        NG/KG           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
CARDIOVASCULAR SYSTEM - CONT                                                                                                        
      Artery, Inflammation, Chronic Active                                                    1 (2%)                                
      Epicardium, Inflammation, Chronic Active                                                             1 (2%)                   
      Epicardium, Inflammation, Suppurative            2 (4%)                                 1 (2%)                                
      Myocardium, Inflammation                                                                             1 (2%)       1 (2%)      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (52)         (55)         (53)         (53)         (53)         (52)         
      Angiectasis                                     11 (21%)     13 (24%)     25 (47%)     19 (36%)     20 (38%)      8 (15%)     
      Atrophy                                          1 (2%)       3 (5%)       5 (9%)       3 (6%)       5 (9%)      19 (37%)     
      Degeneration, Cystic                            11 (21%)     14 (25%)     10 (19%)     14 (26%)     14 (26%)     16 (31%)     
      Hyperplasia                                     23 (44%)     21 (38%)     27 (51%)     25 (47%)     25 (47%)     31 (60%)     
      Hypertrophy                                     34 (65%)     41 (75%)     40 (75%)     41 (77%)     40 (75%)     41 (79%)     
      Inflammation, Suppurative                                                  1 (2%)                                             
      Mineralization                                   1 (2%)                                                           1 (2%)      
      Necrosis                                         1 (2%)       1 (2%)                    1 (2%)       1 (2%)       1 (2%)      
      Thrombosis                                                                                                        1 (2%)      
      Vacuolization Cytoplasmic                        5 (10%)      3 (5%)       5 (9%)       2 (4%)       9 (17%)      4 (8%)      
   Adrenal Medulla                                    (52)         (55)         (53)         (53)         (53)         (52)         
      Angiectasis                                                                2 (4%)       1 (2%)       2 (4%)       2 (4%)      
      Hyperplasia                                      8 (15%)     18 (33%)     11 (21%)     11 (21%)     12 (23%)      6 (12%)     
      Necrosis                                                                                1 (2%)                                
   Islets, Pancreatic                                 (52)         (54)         (53)         (53)         (53)         (52)         
      Hyperplasia                                      1 (2%)       2 (4%)       1 (2%)       1 (2%)                    1 (2%)      
   Parathyroid Gland                                  (47)         (50)         (48)         (46)         (49)         (47)         
      Hyperplasia                                                   1 (2%)       1 (2%)       2 (4%)       1 (2%)       1 (2%)      
   Pituitary Gland                                    (51)         (54)         (53)         (53)         (53)         (53)         
      Angiectasis                                     14 (27%)     15 (28%)     22 (42%)     12 (23%)     16 (30%)     19 (36%)     
      Cyst                                                          3 (6%)       1 (2%)       1 (2%)                    2 (4%)      
      Cytoplasmic Alteration                                        1 (2%)       1 (2%)       1 (2%)       3 (6%)       1 (2%)      
      Inflammation, Focal, Granulomatous                                                                                1 (2%)      
      Necrosis                                                                                             1 (2%)                   
      Pigmentation                                                                                         1 (2%)                   
      Vacuolization Cytoplasmic                                     1 (2%)       1 (2%)                                             
      Pars Distalis, Hyperplasia                      18 (35%)     20 (37%)     23 (43%)     17 (32%)     21 (40%)     26 (49%)     
   Thyroid Gland                                      (52)         (55)         (52)         (51)         (52)         (50)         
      Angiectasis                                                   1 (2%)       4 (8%)                                             
      Cyst                                                                                    1 (2%)                    1 (2%)      
      C-Cell, Hyperplasia                             12 (23%)     21 (38%)     17 (33%)     19 (37%)     18 (35%)     16 (32%)     
      Follicle, Cyst                                                             1 (2%)                                             
      Follicular Cell, Hyperplasia                                               1 (2%)       1 (2%)                                
      Follicular Cell, Hypertrophy                     9 (17%)     13 (24%)     13 (25%)     17 (33%)     28 (54%)     26 (52%)     
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page    5                                                              
                                                                                                                                   
NTP Experiment-Test: 96007-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                           TOXIC EQUIVALENCY FACTOR EVALUATION (PCB-126)                       Date: 10/01/03    
Route: GAVAGE                                                                                                     Time: 11:41:44    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         SPRAGUE-DAWLEY RATS FEMALE                0 NG/KG      30 NG/KG     100          175          300          550             
                                                                             NG/KG        NG/KG        NG/KG        NG/KG           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Clitoral Gland                                     (50)         (55)         (52)         (50)         (53)         (52)         
      Hyperplasia                                                   1 (2%)                                                          
      Hyperplasia, Squamous                                                      1 (2%)                                             
      Inflammation                                    28 (56%)     36 (65%)     39 (75%)     28 (56%)     30 (57%)     27 (52%)     
      Duct, Cyst                                      29 (58%)     32 (58%)     34 (65%)     37 (74%)     39 (74%)     42 (81%)     
   Ovary                                              (52)         (54)         (53)         (52)         (52)         (52)         
      Atrophy                                         45 (87%)     49 (91%)     46 (87%)     45 (87%)     47 (90%)     46 (88%)     
      Cyst                                            12 (23%)     17 (31%)     17 (32%)     15 (29%)     16 (31%)     18 (35%)     
      Inflammation, Chronic Active                                                            1 (2%)       1 (2%)                   
      Inflammation, Suppurative                                     1 (2%)                                              2 (4%)      
      Necrosis                                                                                             1 (2%)                   
      Artery, Inflammation, Chronic Active                                       1 (2%)       1 (2%)                                
   Oviduct                                            (1)          (1)                                    (1)          (3)          
      Cyst                                                                                                              1 (33%)     
      Inflammation, Chronic Active                                                                         1 (100%)                 
      Inflammation, Suppurative                        1 (100%)     1 (100%)                                            2 (67%)     
   Uterus                                             (52)         (55)         (53)         (52)         (53)         (52)         
      Adenomyosis                                                   1 (2%)                    1 (2%)                    2 (4%)      
      Cyst                                                          1 (2%)                                                          
      Erosion                                                                    1 (2%)                                             
      Hemorrhage                                                                              1 (2%)       2 (4%)       1 (2%)      
      Inflammation, Chronic Active                                                            2 (4%)       1 (2%)       1 (2%)      
      Inflammation, Granulomatous                      1 (2%)                                                                       
      Inflammation, Suppurative                       12 (23%)     12 (22%)     11 (21%)     16 (31%)     10 (19%)      6 (12%)     
      Metaplasia, Squamous                            26 (50%)     33 (60%)     25 (47%)     28 (54%)     29 (55%)     27 (52%)     
      Thrombosis                                                                              1 (2%)                    1 (2%)      
      Ulcer                                                         1 (2%)                                                          
      Vacuolization Cytoplasmic                                                  2 (4%)                                             
      Artery, Inflammation, Chronic Active                                       1 (2%)                                 1 (2%)      
      Cervix, Cyst                                                                                         1 (2%)                   
      Cervix, Hyperplasia, Stromal                                                                                      1 (2%)      
      Endometrium, Hyperplasia, Cystic                23 (44%)     33 (60%)     28 (53%)     24 (46%)     26 (49%)     32 (62%)     
      Epithelium, Hyperplasia                          1 (2%)                                 1 (2%)                                
      Epithelium, Necrosis                                                       1 (2%)       1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page    6                                                              
                                                                                                                                   
NTP Experiment-Test: 96007-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                           TOXIC EQUIVALENCY FACTOR EVALUATION (PCB-126)                       Date: 10/01/03    
Route: GAVAGE                                                                                                     Time: 11:41:44    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         SPRAGUE-DAWLEY RATS FEMALE                0 NG/KG      30 NG/KG     100          175          300          550             
                                                                             NG/KG        NG/KG        NG/KG        NG/KG           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (53)         (55)         (53)         (53)         (53)         (53)         
      Angiectasis                                                                                                       1 (2%)      
      Fibrosis                                                                   1 (2%)                                             
      Hyperplasia                                     47 (89%)     37 (67%)     35 (66%)     44 (83%)     45 (85%)     46 (87%)     
   Lymph Node                                         (2)          (6)          (6)          (6)          (4)          (7)          
      Ectasia                                                                                 1 (17%)                               
      Deep Cervical, Ectasia                                                     1 (17%)                                            
      Inguinal, Hyperplasia, Plasma Cell                                         1 (17%)                                            
      Inguinal, Pigmentation                                                     1 (17%)                                            
      Lumbar, Ectasia                                                                                                   2 (29%)     
      Lumbar, Hyperplasia                                                                                               1 (14%)     
      Lumbar, Hyperplasia, Lymphoid                                 1 (17%)                                                         
      Lumbar, Hyperplasia, Plasma Cell                                                        2 (33%)      1 (25%)                  
      Mediastinal, Ectasia                                          2 (33%)      3 (50%)                                            
      Mediastinal, Hemorrhage                                                    2 (33%)      1 (17%)      1 (25%)                  
      Mediastinal, Hyperplasia, Lymphoid                                                                   1 (25%)                  
      Mediastinal, Hyperplasia, Plasma Cell                                                                1 (25%)      1 (14%)     
      Mediastinal, Inflammation, Suppurative                                                               1 (25%)                  
      Pancreatic, Hyperplasia, Plasma Cell                                                                              1 (14%)     
   Lymph Node, Mandibular                             (52)         (53)         (51)         (51)         (52)         (51)         
      Ectasia                                          1 (2%)       1 (2%)       4 (8%)       4 (8%)       4 (8%)       4 (8%)      
      Hemorrhage                                                                                           1 (2%)                   
      Hyperplasia, Lymphoid                                         1 (2%)       1 (2%)       1 (2%)       2 (4%)                   
      Hyperplasia, Plasma Cell                        18 (35%)     24 (45%)     31 (61%)     21 (41%)     29 (56%)     11 (22%)     
   Lymph Node, Mesenteric                             (52)         (54)         (52)         (52)         (53)         (51)         
      Atrophy                                                                    1 (2%)                                             
      Ectasia                                          1 (2%)                                                           1 (2%)      
      Hemorrhage                                       2 (4%)       3 (6%)                    1 (2%)       1 (2%)                   
      Hyperplasia, Histiocytic                         3 (6%)                                                           1 (2%)      
      Hyperplasia, Plasma Cell                                                                             1 (2%)                   
      Pigmentation                                                                                                      1 (2%)      
   Spleen                                             (52)         (55)         (52)         (53)         (53)         (52)         
      Hematopoietic Cell Proliferation                39 (75%)     43 (78%)     46 (88%)     45 (85%)     41 (77%)     42 (81%)     
      Hyperplasia, Lymphoid                                                      1 (2%)                    1 (2%)       1 (2%)      
      Necrosis                                                      1 (2%)                                                          
      Pigmentation                                    49 (94%)     50 (91%)     51 (98%)     51 (96%)     52 (98%)     52 (100%)    
      Lymphoid Follicle, Atrophy                                    5 (9%)       3 (6%)       2 (4%)       5 (9%)       3 (6%)      
      Red Pulp, Atrophy                                                          4 (8%)       1 (2%)       1 (2%)                   
   Thymus                                             (50)         (52)         (46)         (48)         (41)         (49)         
      Atrophy                                         37 (74%)     34 (65%)     41 (89%)     45 (94%)     36 (88%)     47 (96%)     
      Fibrosis                                                                   1 (2%)                                             
      Hemorrhage                                       1 (2%)       1 (2%)                                                          
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page    7                                                              
                                                                                                                                   
NTP Experiment-Test: 96007-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                           TOXIC EQUIVALENCY FACTOR EVALUATION (PCB-126)                       Date: 10/01/03    
Route: GAVAGE                                                                                                     Time: 11:41:44    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         SPRAGUE-DAWLEY RATS FEMALE                0 NG/KG      30 NG/KG     100          175          300          550             
                                                                             NG/KG        NG/KG        NG/KG        NG/KG           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
HEMATOPOIETIC SYSTEM - CONT                                                                                                         
      Inflammation                                     1 (2%)                                 1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (52)         (55)         (53)         (53)         (53)         (52)         
      Cyst                                             8 (15%)      3 (5%)       1 (2%)       4 (8%)       5 (9%)       1 (2%)      
      Fibrosis, Focal                                                                                      1 (2%)                   
      Hyperplasia                                     32 (62%)     33 (60%)     30 (57%)     29 (55%)     21 (40%)     23 (44%)     
      Inflammation, Chronic Active                     1 (2%)                                 2 (4%)       2 (4%)                   
      Inflammation, Granulomatous                      2 (4%)       2 (4%)                    1 (2%)                                
   Skin                                               (52)         (55)         (53)         (53)         (53)         (53)         
      Cyst, Squamous                                   1 (2%)       1 (2%)                                                          
      Ulcer                                                                      1 (2%)                                             
      Dermis, Inflammation, Focal                      1 (2%)                                                                       
      Subcutaneous Tissue, Inflammation,                                                                                            
        Suppurative                                                                           1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (53)         (55)         (53)         (53)         (53)         (53)         
      Inflammation, Chronic Active                     1 (2%)                                                                       
      Osteopetrosis                                                              1 (2%)                    2 (4%)                   
      Cartilage, Hypertrophy, Focal                                                                                     1 (2%)      
   Skeletal Muscle                                    (1)          (1)          (1)                                                 
      Inflammation, Chronic Active                     1 (100%)                                                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (53)         (55)         (53)         (53)         (53)         (53)         
      Hemorrhage                                                                                                        1 (2%)      
      Hydrocephalus                                    1 (2%)                    2 (4%)                                 1 (2%)      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Lung                                               (53)         (55)         (53)         (53)         (53)         (51)         
      Congestion                                       1 (2%)       1 (2%)                                 1 (2%)                   
      Infiltration Cellular, Histiocyte               41 (77%)     49 (89%)     45 (85%)     48 (91%)     45 (85%)     49 (96%)     
      Inflammation, Chronic Active                     5 (9%)       3 (5%)                    1 (2%)       1 (2%)                   
      Inflammation, Granulomatous                      3 (6%)                    2 (4%)                                             
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page    8                                                              
                                                                                                                                   
NTP Experiment-Test: 96007-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                           TOXIC EQUIVALENCY FACTOR EVALUATION (PCB-126)                       Date: 10/01/03    
Route: GAVAGE                                                                                                     Time: 11:41:44    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         SPRAGUE-DAWLEY RATS FEMALE                0 NG/KG      30 NG/KG     100          175          300          550             
                                                                             NG/KG        NG/KG        NG/KG        NG/KG           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
RESPIRATORY SYSTEM - CONT                                                                                                           
      Inflammation, Suppurative                                                                                         1 (2%)      
      Metaplasia, Squamous                             1 (2%)                    1 (2%)       2 (4%)       3 (6%)       9 (18%)     
      Mineralization                                                1 (2%)       1 (2%)                                 1 (2%)      
      Thrombosis                                                    2 (4%)                                              1 (2%)      
      Alveolar Epithelium, Hyperplasia                12 (23%)      1 (2%)                    1 (2%)       2 (4%)                   
      Alveolar Epithelium, Metaplasia, Bronchiolar                 29 (53%)     34 (64%)     41 (77%)     39 (74%)     47 (92%)     
      Serosa, Fibrosis                                                           2 (4%)                                             
      Serosa, Inflammation, Chronic Active                          1 (2%)                                                          
      Serosa, Inflammation, Suppurative                2 (4%)                                 1 (2%)       1 (2%)                   
      Vein, Thrombosis                                                                        1 (2%)                                
   Nose                                               (53)         (54)         (52)         (53)         (52)         (53)         
      Nasolacrimal Duct, Inflammation                               1 (2%)                    1 (2%)       1 (2%)                   
      Nasolacrimal Duct, Glands, Hyperplasia                                                                            1 (2%)      
      Nasolacrimal Duct, Respiratory Epithelium,                                                                                    
         Hyperplasia                                                                                       1 (2%)                   
      Nasopharyngeal Duct, Inflammation,                                                                                            
        Suppurative                                    1 (2%)                    1 (2%)                                             
      Olfactory Epithelium, Inflammation,                                                                                           
        Suppurative                                    1 (2%)                    1 (2%)                                             
      Respiratory Epithelium, Hyperplasia              2 (4%)                    1 (2%)       1 (2%)       2 (4%)       2 (4%)      
      Respiratory Epithelium, Inflammation,                                                                                         
        Suppurative                                                              1 (2%)                    1 (2%)       1 (2%)      
      Respiratory Epithelium, Metaplasia               1 (2%)                                              1 (2%)                   
      Turbinate, Cyst                                                                                                   1 (2%)      
      Turbinate, Inflammation, Suppurative             2 (4%)                    1 (2%)       1 (2%)       2 (4%)                   
   Trachea                                            (53)         (55)         (53)         (53)         (53)         (52)         
      Inflammation                                     1 (2%)                                                                       
      Peritracheal Tissue, Inflammation                1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Ear                                                                                                    (1)                       
      Inflammation                                                                                         1 (100%)                 
   Eye                                                (51)         (55)         (53)         (53)         (53)         (52)         
      Atrophy                                                                    1 (2%)       1 (2%)                                
      Cataract                                                                                             1 (2%)       1 (2%)      
      Edema                                                                                                1 (2%)                   
      Anterior Chamber, Inflammation, Suppurative                                                                       1 (2%)      
      Anterior Chamber, Ciliary Body, Cornea,                                                                                       
        Inflammation, Suppurative                                                1 (2%)                                             
      Cornea, Inflammation, Suppurative                                                                                 1 (2%)      
      Retina, Atrophy                                                            3 (6%)       1 (2%)                    1 (2%)      
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page    9                                                              
                                                                                                                                   
NTP Experiment-Test: 96007-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                           TOXIC EQUIVALENCY FACTOR EVALUATION (PCB-126)                       Date: 10/01/03    
Route: GAVAGE                                                                                                     Time: 11:41:44    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         SPRAGUE-DAWLEY RATS FEMALE                0 NG/KG      30 NG/KG     100          175          300          550             
                                                                             NG/KG        NG/KG        NG/KG        NG/KG           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
SPECIAL SENSES SYSTEM - CONT                                                                                                        
      Retina, Degeneration                                                                                              1 (2%)      
   Harderian Gland                                    (53)         (53)         (53)         (53)         (53)         (52)         
      Inflammation                                     2 (4%)       3 (6%)       6 (11%)      6 (11%)      3 (6%)       3 (6%)      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (53)         (55)         (53)         (53)         (53)         (52)         
      Calculus Micro Observation Only                                            1 (2%)       1 (2%)                    1 (2%)      
      Casts Protein                                    4 (8%)       3 (5%)       1 (2%)       6 (11%)                               
      Cyst                                                                                    2 (4%)                                
      Inflammation, Chronic Active                     2 (4%)       2 (4%)       1 (2%)       1 (2%)       1 (2%)       1 (2%)      
      Inflammation, Suppurative                                                  3 (6%)                                 1 (2%)      
      Mineralization                                  32 (60%)     39 (71%)     44 (83%)     44 (83%)     44 (83%)     39 (75%)     
      Necrosis                                                                   1 (2%)                    1 (2%)       1 (2%)      
      Nephropathy                                     32 (60%)     29 (53%)     38 (72%)     35 (66%)     38 (72%)     42 (81%)     
      Papilla, Angiectasis                                                                                 1 (2%)                   
      Pelvis, Dilatation                               2 (4%)       1 (2%)                                              1 (2%)      
      Pelvis, Inflammation, Chronic Active                          2 (4%)       2 (4%)       2 (4%)                                
      Pelvis, Inflammation, Suppurative                2 (4%)                                              3 (6%)                   
      Renal Tubule, Accumulation, Hyaline Droplet                   1 (2%)                                                          
      Renal Tubule, Dilatation                                                                1 (2%)                                
      Transitional Epithelium, Hyperplasia             4 (8%)       2 (4%)       8 (15%)      4 (8%)       8 (15%)      8 (15%)     
   Ureter                                                                       (1)                                                 
      Mineralization                                                             1 (100%)                                           
      Transitional Epithelium, Hyperplasia                                       1 (100%)                                           
   Urinary Bladder                                    (51)         (54)         (53)         (52)         (52)         (52)         
      Edema                                                                                   1 (2%)                                
      Hemorrhage                                                                              1 (2%)                                
      Inflammation                                     4 (8%)       6 (11%)     10 (19%)      6 (12%)      7 (13%)      4 (8%)      
      Transitional Epithelium, Hyperplasia             1 (2%)       1 (2%)       1 (2%)       2 (4%)       1 (2%)       2 (4%)      
                                                                                                                                    
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page   10                                                              
                                                                                                                                   
NTP Experiment-Test: 96007-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                           TOXIC EQUIVALENCY FACTOR EVALUATION (PCB-126)                       Date: 10/01/03    
Route: GAVAGE                                                                                                     Time: 11:41:44    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         SPRAGUE-DAWLEY RATS FEMALE                1000         1000 NG/                                                            
                                                   NG/KG        KG/STOP                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
DISPOSITION SUMMARY                                                                                                                 
                                                                                                                                    
  Animals Initially In Study                          98           50                                                               
  Early Deaths                                                                                                                      
    Natural Death                                     12            6                                                               
    Moribund Sacrifice                                34           15                                                               
    Dosing Accident                                                 1                                                               
  Survivors                                                                                                                         
    Terminal Sacrifice                                 7           28                                                               
                                                                                                                                    
  Animals Examined Microscopically                    53           50                                                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Esophagus                                          (52)         (50)                                                             
      Cyst                                             1 (2%)                                                                       
      Muscularis, Inflammation                                      1 (2%)                                                          
   Intestine Large, Colon                             (53)         (50)                                                             
      Parasite Metazoan                                1 (2%)                                                                       
   Intestine Large, Rectum                            (53)         (50)                                                             
      Parasite Metazoan                                1 (2%)       1 (2%)                                                          
   Intestine Small, Duodenum                          (53)         (50)                                                             
      Erosion                                          2 (4%)                                                                       
      Ulcer                                            1 (2%)                                                                       
      Epithelium, Hyperplasia                          1 (2%)                                                                       
   Intestine Small, Jejunum                           (53)         (50)                                                             
      Hyperplasia, Lymphoid                            1 (2%)                                                                       
   Liver                                              (53)         (50)                                                             
      Angiectasis                                      2 (4%)       8 (16%)                                                         
      Basophilic Focus                                 2 (4%)       7 (14%)                                                         
      Basophilic Focus, Multiple                       3 (6%)       9 (18%)                                                         
      Cholangiofibrosis                               22 (42%)      1 (2%)                                                          
      Clear Cell Focus                                              1 (2%)                                                          
      Clear Cell Focus, Multiple                                    4 (8%)                                                          
      Cytoplasmic Alteration                           1 (2%)                                                                       
      Degeneration, Cystic                             2 (4%)       3 (6%)                                                          
      Eosinophilic Focus                               6 (11%)      3 (6%)                                                          
      Eosinophilic Focus, Multiple                    11 (21%)      9 (18%)                                                         
      Fatty Change, Diffuse                           47 (89%)     12 (24%)                                                         
      Fatty Change, Focal                                          11 (22%)                                                         
      Hepatocyte, Multinucleate                       49 (92%)     20 (40%)                                                         
      Hepatodiaphragmatic Nodule                       1 (2%)       1 (2%)                                                          
      Hyperplasia, Nodular                            39 (74%)                                                                      
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page   11                                                              
                                                                                                                                   
NTP Experiment-Test: 96007-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                           TOXIC EQUIVALENCY FACTOR EVALUATION (PCB-126)                       Date: 10/01/03    
Route: GAVAGE                                                                                                     Time: 11:41:44    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         SPRAGUE-DAWLEY RATS FEMALE                1000         1000 NG/                                                            
                                                   NG/KG        KG/STOP                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Inflammation                                    51 (96%)     46 (92%)                                                         
      Mixed Cell Focus                                 4 (8%)       1 (2%)                                                          
      Mixed Cell Focus, Multiple                       5 (9%)      35 (70%)                                                         
      Multinucleated                                                1 (2%)                                                          
      Necrosis                                        17 (32%)      4 (8%)                                                          
      Pigmentation                                    48 (91%)     48 (96%)                                                         
      Toxic Hepatopathy                               49 (92%)     15 (30%)                                                         
      Bile Duct, Cyst                                 12 (23%)      5 (10%)                                                         
      Bile Duct, Fibrosis                              5 (9%)       4 (8%)                                                          
      Bile Duct, Hyperplasia                          45 (85%)     16 (32%)                                                         
      Bile Duct, Inflammation                          1 (2%)                                                                       
      Hepatocyte, Degeneration                         7 (13%)                                                                      
      Hepatocyte, Hypertrophy                         49 (92%)     21 (42%)                                                         
      Oval Cell, Hyperplasia                          40 (75%)      1 (2%)                                                          
      Portal, Fibrosis                                10 (19%)                                                                      
      Serosa, Inflammation                             1 (2%)                                                                       
   Mesentery                                          (11)                                                                          
      Inflammation, Chronic Active                     3 (27%)                                                                      
      Artery, Inflammation, Chronic Active             7 (64%)                                                                      
      Fat, Necrosis                                    1 (9%)                                                                       
   Oral Mucosa                                        (11)         (6)                                                              
      Gingival, Cyst, Squamous                         1 (9%)                                                                       
      Gingival, Hyperplasia, Squamous                  3 (27%)      3 (50%)                                                         
      Pharyngeal, Hyperplasia, Squamous                             1 (17%)                                                         
   Pancreas                                           (51)         (48)                                                             
      Basophilic Focus                                              1 (2%)                                                          
      Cyst                                             1 (2%)                                                                       
      Inflammation, Chronic Active                    13 (25%)      4 (8%)                                                          
      Necrosis                                         1 (2%)                                                                       
      Acinus, Atrophy                                 18 (35%)      7 (15%)                                                         
      Acinus, Vacuolization Cytoplasmic               23 (45%)      1 (2%)                                                          
      Artery, Inflammation, Chronic Active            11 (22%)      1 (2%)                                                          
      Duct, Dilatation                                 2 (4%)                                                                       
      Duct, Hyperplasia                                1 (2%)                                                                       
   Salivary Glands                                    (51)         (49)                                                             
      Atrophy                                                       1 (2%)                                                          
      Cyst                                                          2 (4%)                                                          
      Inflammation, Acute                              1 (2%)                                                                       
   Stomach, Forestomach                               (53)         (50)                                                             
      Edema                                                         2 (4%)                                                          
      Hyperkeratosis                                   2 (4%)                                                                       
      Hyperplasia, Squamous                            8 (15%)      2 (4%)                                                          
      Mineralization                                   2 (4%)                                                                       
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page   12                                                              
                                                                                                                                   
NTP Experiment-Test: 96007-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                           TOXIC EQUIVALENCY FACTOR EVALUATION (PCB-126)                       Date: 10/01/03    
Route: GAVAGE                                                                                                     Time: 11:41:44    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         SPRAGUE-DAWLEY RATS FEMALE                1000         1000 NG/                                                            
                                                   NG/KG        KG/STOP                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Ulcer                                            2 (4%)                                                                       
   Stomach, Glandular                                 (53)         (50)                                                             
      Erosion                                                       1 (2%)                                                          
      Inflammation, Chronic Active                     1 (2%)                                                                       
      Mineralization                                   1 (2%)                                                                       
      Artery, Inflammation, Chronic Active             1 (2%)                                                                       
      Glands, Ectasia                                  1 (2%)                                                                       
      Glands, Hyperplasia                              1 (2%)                                                                       
   Tooth                                              (19)         (12)                                                             
      Peridontal Tissue, Fibrosis                      1 (5%)       1 (8%)                                                          
      Peridontal Tissue, Inflammation, Suppurative    18 (95%)     11 (92%)                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Blood Vessel                                       (53)         (50)                                                             
      Aorta, Mineralization                                         1 (2%)                                                          
   Heart                                              (51)         (50)                                                             
      Cardiomyopathy                                  32 (63%)     15 (30%)                                                         
      Mineralization                                                1 (2%)                                                          
      Thrombosis                                       1 (2%)       1 (2%)                                                          
      Artery, Inflammation, Chronic Active                          1 (2%)                                                          
      Endocardium, Myocardium, Inflammation, Acute     1 (2%)                                                                       
      Epicardium, Inflammation, Chronic Active         1 (2%)                                                                       
      Epicardium, Inflammation, Suppurative                         1 (2%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (53)         (50)                                                             
      Angiectasis                                      1 (2%)      14 (28%)                                                         
      Atrophy                                         30 (57%)      9 (18%)                                                         
      Degeneration, Cystic                            10 (19%)     20 (40%)                                                         
      Hyperplasia                                     24 (45%)     26 (52%)                                                         
      Hypertrophy                                     41 (77%)     42 (84%)                                                         
      Inflammation, Suppurative                                     1 (2%)                                                          
      Mineralization                                   1 (2%)                                                                       
      Necrosis                                         2 (4%)       2 (4%)                                                          
      Vacuolization Cytoplasmic                       17 (32%)      6 (12%)                                                         
   Adrenal Medulla                                    (53)         (50)                                                             
      Hyperplasia                                      1 (2%)       9 (18%)                                                         
   Parathyroid Gland                                  (46)         (44)                                                             
      Cyst                                                          1 (2%)                                                          
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page   13                                                              
                                                                                                                                   
NTP Experiment-Test: 96007-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                           TOXIC EQUIVALENCY FACTOR EVALUATION (PCB-126)                       Date: 10/01/03    
Route: GAVAGE                                                                                                     Time: 11:41:44    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         SPRAGUE-DAWLEY RATS FEMALE                1000         1000 NG/                                                            
                                                   NG/KG        KG/STOP                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ENDOCRINE SYSTEM - CONT                                                                                                             
      Hyperplasia                                                   2 (5%)                                                          
   Pituitary Gland                                    (53)         (48)                                                             
      Angiectasis                                      9 (17%)     14 (29%)                                                         
      Cyst                                             1 (2%)       1 (2%)                                                          
      Cytoplasmic Alteration                                        1 (2%)                                                          
      Pars Distalis, Hyperplasia                      17 (32%)     17 (35%)                                                         
   Thyroid Gland                                      (48)         (47)                                                             
      Angiectasis                                                   1 (2%)                                                          
      Atrophy                                          1 (2%)                                                                       
      Infiltration Cellular, Lymphocyte                1 (2%)                                                                       
      C-Cell, Hyperplasia                             19 (40%)     18 (38%)                                                         
      Follicular Cell, Hyperplasia                     1 (2%)                                                                       
      Follicular Cell, Hypertrophy                    16 (33%)     22 (47%)                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Clitoral Gland                                     (51)         (48)                                                             
      Inflammation                                    22 (43%)     32 (67%)                                                         
      Duct, Cyst                                      45 (88%)     39 (81%)                                                         
   Ovary                                              (53)         (50)                                                             
      Atrophy                                         33 (62%)     47 (94%)                                                         
      Cyst                                            11 (21%)     17 (34%)                                                         
   Oviduct                                            (1)          (2)                                                              
      Inflammation, Suppurative                        1 (100%)     2 (100%)                                                        
   Uterus                                             (53)         (50)                                                             
      Hemorrhage                                       1 (2%)                                                                       
      Inflammation, Chronic Active                                  1 (2%)                                                          
      Inflammation, Suppurative                        4 (8%)      11 (22%)                                                         
      Metaplasia, Squamous                            11 (21%)     28 (56%)                                                         
      Endometrium, Hyperplasia, Cystic                 9 (17%)     31 (62%)                                                         
      Epithelium, Hyperplasia                                       1 (2%)                                                          
   Vagina                                             (1)                                                                           
      Cyst                                             1 (100%)                                                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page   14                                                              
                                                                                                                                   
NTP Experiment-Test: 96007-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                           TOXIC EQUIVALENCY FACTOR EVALUATION (PCB-126)                       Date: 10/01/03    
Route: GAVAGE                                                                                                     Time: 11:41:44    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         SPRAGUE-DAWLEY RATS FEMALE                1000         1000 NG/                                                            
                                                   NG/KG        KG/STOP                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
HEMATOPOIETIC SYSTEM - CONT                                                                                                         
   Bone Marrow                                        (53)         (50)                                                             
      Atrophy                                          1 (2%)                                                                       
      Hyperplasia                                     46 (87%)     34 (68%)                                                         
   Lymph Node                                         (12)         (2)                                                              
      Iliac, Ectasia                                                1 (50%)                                                         
      Mediastinal, Angiectasis                         1 (8%)                                                                       
      Mediastinal, Ectasia                             5 (42%)                                                                      
      Mediastinal, Hemorrhage                          6 (50%)                                                                      
      Mediastinal, Hyperplasia, Lymphoid               1 (8%)                                                                       
      Mediastinal, Pigmentation                        2 (17%)                                                                      
      Pancreatic, Hemorrhage                           1 (8%)                                                                       
   Lymph Node, Mandibular                             (51)         (49)                                                             
      Atrophy                                          1 (2%)                                                                       
      Ectasia                                          3 (6%)       3 (6%)                                                          
      Hemorrhage                                       1 (2%)                                                                       
      Hyperplasia, Lymphoid                            1 (2%)                                                                       
      Hyperplasia, Plasma Cell                        15 (29%)     21 (43%)                                                         
   Lymph Node, Mesenteric                             (53)         (50)                                                             
      Atrophy                                          1 (2%)       2 (4%)                                                          
      Ectasia                                          1 (2%)                                                                       
      Hemorrhage                                       2 (4%)                                                                       
      Hyperplasia, Histiocytic                         1 (2%)       1 (2%)                                                          
      Hyperplasia, Lymphoid                            2 (4%)                                                                       
      Hyperplasia, Plasma Cell                                      1 (2%)                                                          
   Spleen                                             (52)         (50)                                                             
      Hematopoietic Cell Proliferation                37 (71%)     37 (74%)                                                         
      Hyperplasia, Lymphoid                            3 (6%)                                                                       
      Pigmentation                                    50 (96%)     50 (100%)                                                        
      Lymphoid Follicle, Atrophy                       6 (12%)      4 (8%)                                                          
      Red Pulp, Atrophy                                2 (4%)                                                                       
   Thymus                                             (44)         (43)                                                             
      Atrophy                                         41 (93%)     39 (91%)                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (53)         (50)                                                             
      Cyst                                             1 (2%)      13 (26%)                                                         
      Hyperplasia                                      9 (17%)     22 (44%)                                                         
   Skin                                               (53)         (50)                                                             
      Cyst, Squamous                                   1 (2%)       2 (4%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page   15                                                              
                                                                                                                                   
NTP Experiment-Test: 96007-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                           TOXIC EQUIVALENCY FACTOR EVALUATION (PCB-126)                       Date: 10/01/03    
Route: GAVAGE                                                                                                     Time: 11:41:44    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         SPRAGUE-DAWLEY RATS FEMALE                1000         1000 NG/                                                            
                                                   NG/KG        KG/STOP                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Skeletal Muscle                                    (1)                                                                           
      Inflammation, Chronic Active                     1 (100%)                                                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (53)         (50)                                                             
      Hemorrhage                                       1 (2%)                                                                       
      Inflammation, Focal, Suppurative                 1 (2%)                                                                       
      Necrosis, Focal                                  1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Lung                                               (51)         (50)                                                             
      Hemorrhage                                       1 (2%)       1 (2%)                                                          
      Infiltration Cellular, Histiocyte               42 (82%)     42 (84%)                                                         
      Inflammation, Chronic Active                     2 (4%)                                                                       
      Metaplasia, Squamous                             4 (8%)                                                                       
      Mineralization                                   1 (2%)       1 (2%)                                                          
      Alveolar Epithelium, Metaplasia, Bronchiolar    40 (78%)     32 (64%)                                                         
      Serosa, Inflammation, Suppurative                             1 (2%)                                                          
   Nose                                               (53)         (50)                                                             
      Goblet Cell, Respiratory Epithelium,                                                                                          
        Hyperplasia                                    1 (2%)                                                                       
      Nasolacrimal Duct, Inflammation                  1 (2%)       1 (2%)                                                          
      Nasolacrimal Duct, Respiratory Epithelium,                                                                                    
         Hyperplasia                                   1 (2%)                                                                       
      Nasopharyngeal Duct, Respiratory Epithelium,                                                                                  
         Hyperplasia                                   1 (2%)                                                                       
      Respiratory Epithelium, Hyperplasia              1 (2%)       1 (2%)                                                          
      Turbinate, Cyst                                  1 (2%)                                                                       
      Turbinate, Inflammation, Suppurative             4 (8%)       1 (2%)                                                          
      Vomeronasal Organ, Vacuolization Cytoplasmic     1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                (52)         (50)                                                             
      Anterior Chamber, Inflammation, Suppurative      1 (2%)       1 (2%)                                                          
      Cornea, Inflammation, Suppurative                2 (4%)       1 (2%)                                                          
      Optic Nerve, Degeneration                        1 (2%)                                                                       
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page   16                                                              
                                                                                                                                   
NTP Experiment-Test: 96007-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                           TOXIC EQUIVALENCY FACTOR EVALUATION (PCB-126)                       Date: 10/01/03    
Route: GAVAGE                                                                                                     Time: 11:41:44    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         SPRAGUE-DAWLEY RATS FEMALE                1000         1000 NG/                                                            
                                                   NG/KG        KG/STOP                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
SPECIAL SENSES SYSTEM - CONT                                                                                                        
      Retina, Atrophy                                  4 (8%)                                                                       
   Harderian Gland                                    (52)         (50)                                                             
      Inflammation                                     6 (12%)      9 (18%)                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (53)         (50)                                                             
      Casts Protein                                    2 (4%)       3 (6%)                                                          
      Inflammation, Suppurative                        2 (4%)                                                                       
      Mineralization                                  37 (70%)     45 (90%)                                                         
      Necrosis                                         1 (2%)                                                                       
      Nephropathy                                     47 (89%)     38 (76%)                                                         
      Papilla, Necrosis                                1 (2%)                                                                       
      Pelvis, Dilatation                               2 (4%)       1 (2%)                                                          
      Pelvis, Hemorrhage                               1 (2%)                                                                       
      Pelvis, Inflammation, Chronic Active             1 (2%)       1 (2%)                                                          
      Pelvis, Metaplasia, Squamous                     1 (2%)                                                                       
      Transitional Epithelium, Hyperplasia            11 (21%)      2 (4%)                                                          
   Ureter                                             (3)                                                                           
      Inflammation                                     1 (33%)                                                                      
      Metaplasia, Squamous                             2 (67%)                                                                      
      Mineralization                                   2 (67%)                                                                      
      Transitional Epithelium, Hyperplasia             3 (100%)                                                                     
   Urinary Bladder                                    (53)         (50)                                                             
      Inflammation                                     6 (11%)      3 (6%)                                                          
      Metaplasia, Squamous                             1 (2%)                                                                       
      Transitional Epithelium, Hyperplasia             2 (4%)                                                                       
                                                                                                                                    
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page   17                                                              
                                                                                                                                   
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                             ----------              END OF REPORT             ----------                                           
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NTP is located at the National Institute of Environmental Health Sciences, part of the National Institutes of Health.