National Toxicology Program

National Toxicology Program
https://ntp.niehs.nih.gov/go/5250

TDMS Study 96007-01 Pathology Tables

NTP Experiment-Test: 96007-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT18
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 10/01/03
Route: GAVAGE                                   TOXIC EQUIVALENCY FACTOR EVALUATION (PCB-126)                     Time: 12:01:01

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

                                                              Page   1


NTP Experiment-Test: 96007-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT18  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 10/01/03    
Route: GAVAGE                                   TOXIC EQUIVALENCY FACTOR EVALUATION (PCB-126)                     Time: 12:01:01    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         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 [3.0]     
      Hyperplasia, Focal, Squamous                                               1 [1.0]                                            
      Muscularis, Degeneration                                                                             1 [2.0]                  
      Muscularis, Inflammation                         2 [1.0]      1 [1.0]                   1 [1.0]      1 [1.0]      2 [1.5]     
      Periesophageal Tissue, Inflammation,                                                                                          
        Suppurative                                                                                        1 [3.0]                  
   Intestine Large, Colon                             (52)         (55)         (53)         (53)         (53)         (51)         
      Hyperplasia, Adenomatous                                                   1 [3.0]                                            
      Inflammation                                                               1 [2.0]                                            
      Parasite Metazoan                                             1            2            1                                     
   Intestine Large, Rectum                            (52)         (55)         (53)         (52)         (53)         (52)         
      Infiltration Cellular, Lymphocyte                                          1 [2.0]                                            
      Inflammation, Chronic Active                                                            1 [2.0]                               
      Mineralization                                                1 [2.0]                                                         
      Parasite Metazoan                                2            2            3                         1                        
      Artery, Inflammation, Chronic Active                                                    1 [3.0]                               
   Intestine Large, Cecum                             (52)         (54)         (53)         (51)         (53)         (52)         
      Edema                                                         1 [2.0]                                                         
      Hyperplasia, Lymphoid                                                                                1 [2.0]                  
      Inflammation                                                  1 [1.0]                                                         
   Intestine Small, Duodenum                          (52)         (55)         (52)         (53)         (53)         (51)         
      Erosion                                          1 [2.0]                                                                      
   Intestine Small, Ileum                             (52)         (54)         (52)         (51)         (53)         (52)         
      Hyperplasia, Lymphoid                                                                                1 [2.0]                  
      Mineralization                                                1 [2.0]                                                         
      Epithelium, Hyperplasia                                                                 1 [2.0]                               
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Average severity grade (1-minimal;2-mild;3-moderate;4-marked)                                                                    
                                                                                                                                    
                                                             Page    2                                                              
                                                                                                                                   
NTP Experiment-Test: 96007-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT18  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 10/01/03    
Route: GAVAGE                                   TOXIC EQUIVALENCY FACTOR EVALUATION (PCB-126)                     Time: 12:01:01    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         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 [3.0]                                                                      
   Liver                                              (53)         (55)         (53)         (53)         (53)         (51)         
      Angiectasis                                      3 [1.3]      8 [1.4]      4 [1.0]      1 [2.0]      1 [2.0]      2 [1.5]     
      Basophilic Focus                                 2            4            6            7            2            3           
      Basophilic Focus, Multiple                       5            6            4            6            2            2           
      Cholangiofibrosis                                             1 [2.0]      1 [2.0]      1 [2.0]      3 [1.7]     13 [1.8]     
      Clear Cell Focus                                 1            1                                                               
      Clear Cell Focus, Multiple                       1                                                                            
      Cytoplasmic Alteration                                                     1 [2.0]      1 [2.0]      1 [2.0]      1 [2.0]     
      Degeneration, Cystic                                                                                 1 [1.0]      1 [2.0]     
      Eosinophilic Focus                               6            4            7            4            2            3           
      Eosinophilic Focus, Multiple                     5            6            6           17           15           21           
      Fatty Change, Diffuse                            5 [1.2]      7 [1.0]     14 [1.4]     22 [1.1]     30 [1.1]     45 [1.4]     
      Fatty Change, Focal                              2 [1.5]      6 [1.3]      8 [1.5]      6 [1.5]      3 [1.7]      2 [1.0]     
      Hematopoietic Cell Proliferation                                                                                  1 [2.0]     
      Hepatocyte, Multinucleate                                     2 [1.0]     10 [1.1]     14 [1.0]     19 [1.3]     46 [1.5]     
      Hepatodiaphragmatic Nodule                       1            1                         1                                     
      Hyperplasia, Nodular                                                                    1            3           26           
      Inflammation                                    36 [1.1]     40 [1.1]     49 [1.2]     50 [1.2]     51 [1.2]     51 [1.4]     
      Mixed Cell Focus                                 4            6            7            3                         3           
      Mixed Cell Focus, Multiple                      17           18           25           29           30           26           
      Necrosis                                         4 [2.3]      2 [2.0]      5 [1.6]      8 [2.1]     11 [1.9]     15 [2.0]     
      Pigmentation                                     1 [1.0]     11 [1.3]     41 [1.2]     39 [1.6]     48 [1.9]     51 [2.3]     
      Toxic Hepatopathy                                             6 [1.2]     22 [1.0]     27 [1.0]     39 [1.3]     51 [2.4]     
      Vacuolization Cytoplasmic                                     1 [1.0]                                                         
      Artery, Inflammation, Chronic Active                                                    1 [2.0]      1 [2.0]      1 [2.0]     
      Bile Duct, Cyst                                  3 [1.7]      6 [2.3]                   2 [2.0]      3 [2.7]      8 [2.0]     
      Bile Duct, Fibrosis                              4 [1.0]      4 [1.5]      3 [1.3]      2 [1.0]      1 [1.0]      4 [1.0]     
      Bile Duct, Hyperplasia                           3 [1.3]      7 [1.6]      7 [1.6]     13 [1.4]     14 [1.2]     45 [1.8]     
      Hepatocyte, Degeneration                         3 [2.3]      1 [2.0]      1 [2.0]                   1 [1.0]      1 [1.0]     
      Hepatocyte, Hypertrophy                                      23 [1.1]     32 [1.2]     36 [1.3]     42 [1.4]     50 [2.3]     
      Oval Cell, Hyperplasia                                        1 [1.0]      6 [1.2]      7 [1.1]     10 [1.2]     38 [1.8]     
      Portal, Fibrosis                                                                                     2 [2.0]      1 [1.0]     
      Serosa, Inflammation                                          1 [2.0]                                                         
   Mesentery                                          (1)                       (4)          (2)          (7)          (13)         
      Inflammation, Chronic Active                     1 [4.0]                                                                      
      Artery, Inflammation, Chronic Active                                       2 [3.0]      2 [3.5]      6 [3.2]     10 [2.6]     
      Fat, Necrosis                                                              1 [3.0]                   1 [3.0]      1 [3.0]     
   Oral Mucosa                                        (1)          (1)          (3)          (4)          (2)          (6)          
      Gingival, Hyperplasia, Squamous                  1 [2.0]                   2 [1.0]      2 [2.0]                   4 [1.5]     
   Pancreas                                           (51)         (55)         (53)         (53)         (53)         (52)         
      Basophilic Focus                                              1                         1                                     
      Cyst                                                                                                              1 [2.0]     
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Average severity grade (1-minimal;2-mild;3-moderate;4-marked)                                                                    
                                                                                                                                    
                                                             Page    3                                                              
                                                                                                                                   
NTP Experiment-Test: 96007-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT18  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 10/01/03    
Route: GAVAGE                                   TOXIC EQUIVALENCY FACTOR EVALUATION (PCB-126)                     Time: 12:01:01    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         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 [1.6]      1 [1.0]      3 [2.0]      4 [1.3]      4 [1.8]      6 [2.3]     
      Acinus, Atrophy                                  5 [2.0]      3 [1.3]      2 [2.5]      7 [1.6]      2 [2.5]     11 [2.2]     
      Acinus, Hyperplasia                                           1 [2.0]      1 [3.0]      1 [2.0]      1 [2.0]                  
      Acinus, Vacuolization Cytoplasmic                                          1 [1.0]      4 [1.5]      9 [1.0]     20 [1.1]     
      Artery, Inflammation, Chronic Active                          4 [2.0]      2 [3.0]      4 [2.5]      8 [2.5]     15 [2.5]     
      Artery, Mineralization                                        1 [2.0]                                             1 [2.0]     
      Duct, Hyperplasia                                                                                                 1 [4.0]     
      Duct, Inflammation, Chronic Active                                                                                2 [3.0]     
   Salivary Glands                                    (51)         (54)         (53)         (51)         (52)         (51)         
      Atrophy                                                                                 1 [1.0]      1 [2.0]                  
      Cyst                                                          1 [2.0]                                1 [2.0]                  
      Inflammation, Acute                                                                                  1 [1.0]                  
      Inflammation, Chronic Active                     1 [2.0]                                             1 [2.0]                  
   Stomach, Forestomach                               (52)         (55)         (53)         (53)         (53)         (51)         
      Edema                                            1 [3.0]                   1 [2.0]                   1 [2.0]                  
      Erosion                                                       1 [1.0]                                                         
      Hyperkeratosis                                                3 [1.7]      1 [2.0]      1 [1.0]      3 [1.7]      1 [2.0]     
      Hyperplasia, Squamous                            3 [1.7]      4 [2.0]      6 [1.8]      2 [2.0]      5 [1.8]      6 [1.7]     
      Inflammation, Acute                              1 [1.0]                                                                      
      Inflammation, Chronic Active                                  1 [3.0]      2 [2.0]      1 [2.0]      1 [2.0]                  
      Mineralization                                   1 [2.0]                   1 [3.0]      1 [2.0]                   1 [2.0]     
      Necrosis, Focal                                                            1 [2.0]                                            
      Ulcer                                            3 [2.0]      1 [2.0]                   1 [2.0]      3 [2.3]      2 [2.0]     
   Stomach, Glandular                                 (51)         (53)         (53)         (53)         (53)         (51)         
      Erosion                                          1 [2.0]      1 [2.0]                   1 [2.0]                               
      Metaplasia, Focal                                                          1 [2.0]                                            
      Mineralization                                   1 [2.0]      1 [3.0]                   1 [1.0]                               
   Tooth                                              (12)         (12)         (10)         (9)          (10)         (9)          
      Peridontal Tissue, Inflammation, Chronic                                                                                      
        Active                                         2 [2.5]                                                          1 [4.0]     
      Peridontal Tissue, Inflammation, Suppurative    10 [1.3]     12 [1.3]     10 [1.4]      9 [1.4]     10 [1.4]      8 [1.8]     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Blood Vessel                                       (53)         (55)         (53)         (53)         (53)         (53)         
      Aorta, Mineralization                            3 [1.3]      1 [3.0]      1 [3.0]                                2 [1.0]     
   Heart                                              (52)         (54)         (53)         (53)         (53)         (51)         
      Cardiomyopathy                                   9 [1.0]     16 [1.1]     17 [1.1]     16 [1.2]     24 [1.1]     28 [1.1]     
      Degeneration                                     1 [2.0]      1 [3.0]                                             1 [3.0]     
      Inflammation                                                  1 [2.0]                                                         
      Mineralization                                   1 [2.0]      1 [2.0]                                             1 [2.0]     
      Thrombosis                                       1 [2.0]                                                          1 [2.0]     
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Average severity grade (1-minimal;2-mild;3-moderate;4-marked)                                                                    
                                                                                                                                    
                                                             Page    4                                                              
                                                                                                                                   
NTP Experiment-Test: 96007-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT18  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 10/01/03    
Route: GAVAGE                                   TOXIC EQUIVALENCY FACTOR EVALUATION (PCB-126)                     Time: 12:01:01    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         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 [2.0]                               
      Epicardium, Inflammation, Chronic Active                                                             1 [3.0]                  
      Epicardium, Inflammation, Suppurative            2 [2.0]                                1 [4.0]                               
      Myocardium, Inflammation                                                                             1 [3.0]      1 [1.0]     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (52)         (55)         (53)         (53)         (53)         (52)         
      Angiectasis                                     11 [1.5]     13 [1.5]     25 [1.5]     19 [1.7]     20 [1.5]      8 [1.4]     
      Atrophy                                          1 [1.0]      3 [2.3]      5 [1.2]      3 [1.0]      5 [1.6]     19 [1.8]     
      Degeneration, Cystic                            11 [2.1]     14 [2.4]     10 [2.0]     14 [2.8]     14 [2.1]     16 [2.3]     
      Hyperplasia                                     23 [1.9]     21 [2.4]     27 [2.1]     25 [2.0]     25 [2.4]     31 [2.7]     
      Hypertrophy                                     34 [1.9]     41 [2.0]     40 [1.9]     41 [2.1]     40 [1.9]     41 [2.0]     
      Inflammation, Suppurative                                                  1 [1.0]                                            
      Mineralization                                   1 [2.0]                                                          1 [1.0]     
      Necrosis                                         1 [2.0]      1 [2.0]                   1 [3.0]      1 [2.0]      1 [2.0]     
      Thrombosis                                                                                                        1 [2.0]     
      Vacuolization Cytoplasmic                        5 [1.2]      3 [1.7]      5 [2.0]      2 [2.0]      9 [1.9]      4 [1.0]     
   Adrenal Medulla                                    (52)         (55)         (53)         (53)         (53)         (52)         
      Angiectasis                                                                2 [2.0]      1 [2.0]      2 [2.5]      2 [2.5]     
      Hyperplasia                                      8 [1.5]     18 [2.0]     11 [1.7]     11 [2.0]     12 [1.8]      6 [2.0]     
      Necrosis                                                                                1 [3.0]                               
   Islets, Pancreatic                                 (52)         (54)         (53)         (53)         (53)         (52)         
      Hyperplasia                                      1 [2.0]      2 [2.0]      1 [1.0]      1 [1.0]                   1 [1.0]     
   Parathyroid Gland                                  (47)         (50)         (48)         (46)         (49)         (47)         
      Hyperplasia                                                   1 [2.0]      1 [2.0]      2 [1.5]      1 [3.0]      1 [1.0]     
   Pituitary Gland                                    (51)         (54)         (53)         (53)         (53)         (53)         
      Angiectasis                                     14 [2.1]     15 [2.1]     22 [2.2]     12 [2.3]     16 [2.3]     19 [2.3]     
      Cyst                                                          3 [2.3]      1 [2.0]      1 [1.0]                   2 [2.5]     
      Cytoplasmic Alteration                                        1 [2.0]      1 [2.0]      1 [2.0]      3 [2.0]      1 [2.0]     
      Inflammation, Focal, Granulomatous                                                                                1 [2.0]     
      Necrosis                                                                                             1 [2.0]                  
      Pigmentation                                                                                         1 [2.0]                  
      Vacuolization Cytoplasmic                                     1 [2.0]      1 [1.0]                                            
      Pars Distalis, Hyperplasia                      18 [1.9]     20 [2.5]     23 [2.2]     17 [2.1]     21 [1.9]     26 [2.2]     
   Thyroid Gland                                      (52)         (55)         (52)         (51)         (52)         (50)         
      Angiectasis                                                   1 [2.0]      4 [2.0]                                            
      Cyst                                                                                    1 [2.0]                   1 [2.0]     
      C-Cell, Hyperplasia                             12 [1.9]     21 [1.7]     17 [1.5]     19 [1.8]     18 [1.9]     16 [1.9]     
      Follicle, Cyst                                                             1 [2.0]                                            
      Follicular Cell, Hyperplasia                                               1 [1.0]      1 [1.0]                               
      Follicular Cell, Hypertrophy                     9 [1.3]     13 [1.2]     13 [1.5]     17 [1.1]     28 [1.5]     26 [1.3]     
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Average severity grade (1-minimal;2-mild;3-moderate;4-marked)                                                                    
                                                                                                                                    
                                                             Page    5                                                              
                                                                                                                                   
NTP Experiment-Test: 96007-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT18  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 10/01/03    
Route: GAVAGE                                   TOXIC EQUIVALENCY FACTOR EVALUATION (PCB-126)                     Time: 12:01:01    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         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 [2.0]                                                         
      Hyperplasia, Squamous                                                      1 [1.0]                                            
      Inflammation                                    28 [1.5]     36 [1.4]     39 [1.7]     28 [1.6]     30 [1.4]     27 [1.3]     
      Duct, Cyst                                      29 [1.9]     32 [2.0]     34 [2.0]     37 [1.9]     39 [2.0]     42 [2.2]     
   Ovary                                              (52)         (54)         (53)         (52)         (52)         (52)         
      Atrophy                                         45 [4.0]     49 [4.0]     46 [4.0]     45 [4.0]     47 [4.0]     46 [4.0]     
      Cyst                                            12 [2.0]     17 [2.2]     17 [2.4]     15 [2.3]     16 [2.1]     18 [2.1]     
      Inflammation, Chronic Active                                                            1 [2.0]      1 [3.0]                  
      Inflammation, Suppurative                                     1 [1.0]                                             2 [2.5]     
      Necrosis                                                                                             1 [4.0]                  
      Artery, Inflammation, Chronic Active                                       1 [3.0]      1 [2.0]                               
   Oviduct                                            (1)          (1)                                    (1)          (3)          
      Cyst                                                                                                              1 [4.0]     
      Inflammation, Chronic Active                                                                         1 [3.0]                  
      Inflammation, Suppurative                        1 [2.0]      1 [1.0]                                             2 [2.5]     
   Uterus                                             (52)         (55)         (53)         (52)         (53)         (52)         
      Adenomyosis                                                   1 [2.0]                   1 [4.0]                   2 [2.5]     
      Cyst                                                          1 [3.0]                                                         
      Erosion                                                                    1 [2.0]                                            
      Hemorrhage                                                                              1 [2.0]      2 [3.0]      1 [3.0]     
      Inflammation, Chronic Active                                                            2 [3.0]      1 [4.0]      1 [2.0]     
      Inflammation, Granulomatous                      1 [2.0]                                                                      
      Inflammation, Suppurative                       12 [1.8]     12 [1.8]     11 [1.6]     16 [2.0]     10 [1.6]      6 [2.2]     
      Metaplasia, Squamous                            26 [1.6]     33 [1.9]     25 [2.1]     28 [2.3]     29 [1.8]     27 [2.2]     
      Thrombosis                                                                              1 [2.0]                   1 [3.0]     
      Ulcer                                                         1 [2.0]                                                         
      Vacuolization Cytoplasmic                                                  2 [2.0]                                            
      Artery, Inflammation, Chronic Active                                       1 [3.0]                                1 [3.0]     
      Cervix, Cyst                                                                                         1 [2.0]                  
      Cervix, Hyperplasia, Stromal                                                                                      1 [3.0]     
      Endometrium, Hyperplasia, Cystic                23 [1.7]     33 [2.1]     28 [1.8]     24 [2.5]     26 [2.0]     32 [2.2]     
      Epithelium, Hyperplasia                          1 [3.0]                                1 [3.0]                               
      Epithelium, Necrosis                                                       1 [2.0]      1 [2.0]                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Average severity grade (1-minimal;2-mild;3-moderate;4-marked)                                                                    
                                                                                                                                    
                                                             Page    6                                                              
                                                                                                                                   
NTP Experiment-Test: 96007-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT18  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 10/01/03    
Route: GAVAGE                                   TOXIC EQUIVALENCY FACTOR EVALUATION (PCB-126)                     Time: 12:01:01    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         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 [2.0]     
      Fibrosis                                                                   1 [3.0]                                            
      Hyperplasia                                     47 [3.4]     37 [3.2]     35 [3.3]     44 [3.3]     45 [3.2]     46 [3.2]     
   Lymph Node                                         (2)          (6)          (6)          (6)          (4)          (7)          
      Ectasia                                                                                 1 [2.0]                               
      Deep Cervical, Ectasia                                                     1 [2.0]                                            
      Inguinal, Hyperplasia, Plasma Cell                                         1 [2.0]                                            
      Inguinal, Pigmentation                                                     1 [2.0]                                            
      Lumbar, Ectasia                                                                                                   2 [2.0]     
      Lumbar, Hyperplasia                                                                                               1 [2.0]     
      Lumbar, Hyperplasia, Lymphoid                                 1 [2.0]                                                         
      Lumbar, Hyperplasia, Plasma Cell                                                        2 [2.5]      1 [3.0]                  
      Mediastinal, Ectasia                                          2 [1.5]      3 [2.0]                                            
      Mediastinal, Hemorrhage                                                    2 [2.0]      1 [2.0]      1 [2.0]                  
      Mediastinal, Hyperplasia, Lymphoid                                                                   1 [3.0]                  
      Mediastinal, Hyperplasia, Plasma Cell                                                                1 [2.0]      1 [3.0]     
      Mediastinal, Inflammation, Suppurative                                                               1 [2.0]                  
      Pancreatic, Hyperplasia, Plasma Cell                                                                              1 [2.0]     
   Lymph Node, Mandibular                             (52)         (53)         (51)         (51)         (52)         (51)         
      Ectasia                                          1 [2.0]      1 [3.0]      4 [2.0]      4 [2.5]      4 [2.0]      4 [2.5]     
      Hemorrhage                                                                                           1 [2.0]                  
      Hyperplasia, Lymphoid                                         1 [2.0]      1 [2.0]      1 [2.0]      2 [2.0]                  
      Hyperplasia, Plasma Cell                        18 [2.2]     24 [2.0]     31 [2.2]     21 [2.3]     29 [2.0]     11 [2.2]     
   Lymph Node, Mesenteric                             (52)         (54)         (52)         (52)         (53)         (51)         
      Atrophy                                                                    1 [3.0]                                            
      Ectasia                                          1 [2.0]                                                          1 [2.0]     
      Hemorrhage                                       2 [2.0]      3 [2.0]                   1 [2.0]      1 [2.0]                  
      Hyperplasia, Histiocytic                         3 [1.7]                                                          1 [2.0]     
      Hyperplasia, Plasma Cell                                                                             1 [2.0]                  
      Pigmentation                                                                                                      1 [1.0]     
   Spleen                                             (52)         (55)         (52)         (53)         (53)         (52)         
      Hematopoietic Cell Proliferation                39 [1.7]     43 [1.6]     46 [1.4]     45 [1.5]     41 [1.7]     42 [1.4]     
      Hyperplasia, Lymphoid                                                      1 [2.0]                   1 [2.0]      1 [3.0]     
      Necrosis                                                      1 [2.0]                                                         
      Pigmentation                                    49 [1.3]     50 [1.4]     51 [1.5]     51 [1.4]     52 [1.5]     52 [1.5]     
      Lymphoid Follicle, Atrophy                                    5 [2.6]      3 [2.0]      2 [1.5]      5 [2.0]      3 [2.3]     
      Red Pulp, Atrophy                                                          4 [2.0]      1 [2.0]      1 [2.0]                  
   Thymus                                             (50)         (52)         (46)         (48)         (41)         (49)         
      Atrophy                                         37 [2.5]     34 [2.6]     41 [2.8]     45 [2.8]     36 [3.3]     47 [3.5]     
      Fibrosis                                                                   1 [2.0]                                            
      Hemorrhage                                       1 [3.0]      1 [1.0]                                                         
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Average severity grade (1-minimal;2-mild;3-moderate;4-marked)                                                                    
                                                                                                                                    
                                                             Page    7                                                              
                                                                                                                                   
NTP Experiment-Test: 96007-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT18  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 10/01/03    
Route: GAVAGE                                   TOXIC EQUIVALENCY FACTOR EVALUATION (PCB-126)                     Time: 12:01:01    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         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 [3.0]                                1 [3.0]                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (52)         (55)         (53)         (53)         (53)         (52)         
      Cyst                                             8 [1.8]      3 [1.7]      1 [4.0]      4 [3.3]      5 [2.6]      1 [2.0]     
      Fibrosis, Focal                                                                                      1 [2.0]                  
      Hyperplasia                                     32 [1.4]     33 [1.4]     30 [1.4]     29 [1.2]     21 [1.2]     23 [1.1]     
      Inflammation, Chronic Active                     1 [3.0]                                2 [3.0]      2 [2.0]                  
      Inflammation, Granulomatous                      2 [2.0]      2 [3.0]                   1 [2.0]                               
   Skin                                               (52)         (55)         (53)         (53)         (53)         (53)         
      Cyst, Squamous                                   1 [2.0]      1 [3.0]                                                         
      Ulcer                                                                      1 [2.0]                                            
      Dermis, Inflammation, Focal                      1 [2.0]                                                                      
      Subcutaneous Tissue, Inflammation,                                                                                            
        Suppurative                                                                           1 [2.0]                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (53)         (55)         (53)         (53)         (53)         (53)         
      Inflammation, Chronic Active                     1 [2.0]                                                                      
      Osteopetrosis                                                              1 [2.0]                   2 [2.0]                  
      Cartilage, Hypertrophy, Focal                                                                                     1 [2.0]     
   Skeletal Muscle                                    (1)          (1)          (1)                                                 
      Inflammation, Chronic Active                     1 [3.0]                                                                      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (53)         (55)         (53)         (53)         (53)         (53)         
      Hemorrhage                                                                                                        1 [3.0]     
      Hydrocephalus                                    1 [1.0]                   2 [2.0]                                1 [2.0]     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Lung                                               (53)         (55)         (53)         (53)         (53)         (51)         
      Congestion                                       1 [3.0]      1 [2.0]                                1 [2.0]                  
      Infiltration Cellular, Histiocyte               41 [1.7]     49 [1.7]     45 [1.7]     48 [1.6]     45 [1.6]     49 [1.7]     
      Inflammation, Chronic Active                     5 [1.4]      3 [1.3]                   1 [2.0]      1 [2.0]                  
      Inflammation, Granulomatous                      3 [1.7]                   2 [1.5]                                            
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Average severity grade (1-minimal;2-mild;3-moderate;4-marked)                                                                    
                                                                                                                                    
                                                             Page    8                                                              
                                                                                                                                   
NTP Experiment-Test: 96007-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT18  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 10/01/03    
Route: GAVAGE                                   TOXIC EQUIVALENCY FACTOR EVALUATION (PCB-126)                     Time: 12:01:01    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         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 [2.0]     
      Metaplasia, Squamous                             1 [2.0]                   1 [2.0]      2 [1.5]      3 [2.3]      9 [1.7]     
      Mineralization                                                1 [3.0]      1 [3.0]                                1 [2.0]     
      Thrombosis                                                    2 [2.5]                                             1 [2.0]     
      Alveolar Epithelium, Hyperplasia                12 [1.1]      1 [1.0]                   1 [3.0]      2 [1.0]                  
      Alveolar Epithelium, Metaplasia, Bronchiolar                 29 [1.3]     34 [1.6]     41 [1.8]     39 [1.7]     47 [2.1]     
      Serosa, Fibrosis                                                           2 [1.5]                                            
      Serosa, Inflammation, Chronic Active                          1 [2.0]                                                         
      Serosa, Inflammation, Suppurative                2 [2.5]                                1 [3.0]      1 [3.0]                  
      Vein, Thrombosis                                                                        1 [3.0]                               
   Nose                                               (53)         (54)         (52)         (53)         (52)         (53)         
      Nasolacrimal Duct, Inflammation                               1 [2.0]                   1 [2.0]      1 [2.0]                  
      Nasolacrimal Duct, Glands, Hyperplasia                                                                            1 [4.0]     
      Nasolacrimal Duct, Respiratory Epithelium,                                                                                    
         Hyperplasia                                                                                       1 [2.0]                  
      Nasopharyngeal Duct, Inflammation,                                                                                            
        Suppurative                                    1 [4.0]                   1 [3.0]                                            
      Olfactory Epithelium, Inflammation,                                                                                           
        Suppurative                                    1 [3.0]                   1 [3.0]                                            
      Respiratory Epithelium, Hyperplasia              2 [2.5]                   1 [2.0]      1 [2.0]      2 [2.0]      2 [2.5]     
      Respiratory Epithelium, Inflammation,                                                                                         
        Suppurative                                                              1 [3.0]                   1 [2.0]      1 [3.0]     
      Respiratory Epithelium, Metaplasia               1 [4.0]                                             1 [2.0]                  
      Turbinate, Cyst                                                                                                   1 [1.0]     
      Turbinate, Inflammation, Suppurative             2 [2.0]                   1 [2.0]      1 [1.0]      2 [2.5]                  
   Trachea                                            (53)         (55)         (53)         (53)         (53)         (52)         
      Inflammation                                     1 [2.0]                                                                      
      Peritracheal Tissue, Inflammation                1 [3.0]                                                                      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Ear                                                                                                    (1)                       
      Inflammation                                                                                         1 [1.0]                  
   Eye                                                (51)         (55)         (53)         (53)         (53)         (52)         
      Atrophy                                                                    1 [3.0]      1 [3.0]                               
      Cataract                                                                                             1 [3.0]      1 [3.0]     
      Edema                                                                                                1 [3.0]                  
      Anterior Chamber, Inflammation, Suppurative                                                                       1 [3.0]     
      Anterior Chamber, Ciliary Body, Cornea,                                                                                       
        Inflammation, Suppurative                                                1 [2.0]                                            
      Cornea, Inflammation, Suppurative                                                                                 1 [3.0]     
      Retina, Atrophy                                                            3 [2.3]      1 [3.0]                   1 [3.0]     
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Average severity grade (1-minimal;2-mild;3-moderate;4-marked)                                                                    
                                                                                                                                    
                                                             Page    9                                                              
                                                                                                                                   
NTP Experiment-Test: 96007-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT18  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 10/01/03    
Route: GAVAGE                                   TOXIC EQUIVALENCY FACTOR EVALUATION (PCB-126)                     Time: 12:01:01    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         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 [2.0]     
   Harderian Gland                                    (53)         (53)         (53)         (53)         (53)         (52)         
      Inflammation                                     2 [1.0]      3 [1.0]      6 [1.2]      6 [1.2]      3 [1.0]      3 [1.0]     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (53)         (55)         (53)         (53)         (53)         (52)         
      Calculus Micro Observation Only                                            1            1                         1           
      Casts Protein                                    4 [1.3]      3 [1.3]      1 [1.0]      6 [1.2]                               
      Cyst                                                                                    2 [1.5]                               
      Inflammation, Chronic Active                     2 [2.0]      2 [2.0]      1 [3.0]      1 [3.0]      1 [1.0]      1 [2.0]     
      Inflammation, Suppurative                                                  3 [1.0]                                1 [3.0]     
      Mineralization                                  32 [1.0]     39 [1.0]     44 [1.0]     44 [1.0]     44 [1.0]     39 [1.1]     
      Necrosis                                                                   1 [2.0]                   1 [3.0]      1 [3.0]     
      Nephropathy                                     32 [1.3]     29 [1.3]     38 [1.5]     35 [1.3]     38 [1.5]     42 [2.1]     
      Papilla, Angiectasis                                                                                 1 [2.0]                  
      Pelvis, Dilatation                               2 [2.0]      1 [3.0]                                             1 [2.0]     
      Pelvis, Inflammation, Chronic Active                          2 [2.5]      2 [2.5]      2 [2.5]                               
      Pelvis, Inflammation, Suppurative                2 [1.0]                                             3 [2.0]                  
      Renal Tubule, Accumulation, Hyaline Droplet                   1 [3.0]                                                         
      Renal Tubule, Dilatation                                                                1 [2.0]                               
      Transitional Epithelium, Hyperplasia             4 [2.0]      2 [2.5]      8 [1.9]      4 [2.5]      8 [1.6]      8 [2.3]     
   Ureter                                                                       (1)                                                 
      Mineralization                                                             1 [3.0]                                            
      Transitional Epithelium, Hyperplasia                                       1 [2.0]                                            
   Urinary Bladder                                    (51)         (54)         (53)         (52)         (52)         (52)         
      Edema                                                                                   1 [3.0]                               
      Hemorrhage                                                                              1 [2.0]                               
      Inflammation                                     4 [1.5]      6 [1.5]     10 [1.4]      6 [2.2]      7 [1.6]      4 [1.0]     
      Transitional Epithelium, Hyperplasia             1 [2.0]      1 [3.0]      1 [2.0]      2 [2.5]      1 [3.0]      2 [2.5]     
                                                                                                                                    
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Average severity grade (1-minimal;2-mild;3-moderate;4-marked)                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page   10                                                              
                                                                                                                                   
NTP Experiment-Test: 96007-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT18  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 10/01/03    
Route: GAVAGE                                   TOXIC EQUIVALENCY FACTOR EVALUATION (PCB-126)                     Time: 12:01:01    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         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 [2.0]                                                                      
      Muscularis, Inflammation                                      1 [1.0]                                                         
   Intestine Large, Colon                             (53)         (50)                                                             
      Parasite Metazoan                                1                                                                            
   Intestine Large, Rectum                            (53)         (50)                                                             
      Parasite Metazoan                                1            1                                                               
   Intestine Small, Duodenum                          (53)         (50)                                                             
      Erosion                                          2 [1.5]                                                                      
      Ulcer                                            1 [3.0]                                                                      
      Epithelium, Hyperplasia                          1 [2.0]                                                                      
   Intestine Small, Jejunum                           (53)         (50)                                                             
      Hyperplasia, Lymphoid                            1 [2.0]                                                                      
   Liver                                              (53)         (50)                                                             
      Angiectasis                                      2 [2.0]      8 [1.5]                                                         
      Basophilic Focus                                 2            7                                                               
      Basophilic Focus, Multiple                       3            9                                                               
      Cholangiofibrosis                               22 [2.3]      1 [1.0]                                                         
      Clear Cell Focus                                              1                                                               
      Clear Cell Focus, Multiple                                    4                                                               
      Cytoplasmic Alteration                           1 [3.0]                                                                      
      Degeneration, Cystic                             2 [2.0]      3 [2.0]                                                         
      Eosinophilic Focus                               6            3                                                               
      Eosinophilic Focus, Multiple                    11            9                                                               
      Fatty Change, Diffuse                           47 [1.8]     12 [1.3]                                                         
      Fatty Change, Focal                                          11 [1.5]                                                         
      Hepatocyte, Multinucleate                       49 [1.7]     20 [1.0]                                                         
      Hepatodiaphragmatic Nodule                       1            1                                                               
      Hyperplasia, Nodular                            39                                                                            
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Average severity grade (1-minimal;2-mild;3-moderate;4-marked)                                                                    
                                                                                                                                    
                                                             Page   11                                                              
                                                                                                                                   
NTP Experiment-Test: 96007-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT18  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 10/01/03    
Route: GAVAGE                                   TOXIC EQUIVALENCY FACTOR EVALUATION (PCB-126)                     Time: 12:01:01    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         SPRAGUE-DAWLEY RATS FEMALE                   1000         1000 NG/                                                         
                                                      NG/KG        KG/STOP                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Inflammation                                    51 [1.2]     46 [1.2]                                                         
      Mixed Cell Focus                                 4            1                                                               
      Mixed Cell Focus, Multiple                       5           35                                                               
      Multinucleated                                                1 [1.0]                                                         
      Necrosis                                        17 [2.2]      4 [2.8]                                                         
      Pigmentation                                    48 [2.5]     48 [1.8]                                                         
      Toxic Hepatopathy                               49 [3.4]     15 [1.2]                                                         
      Bile Duct, Cyst                                 12 [2.0]      5 [2.2]                                                         
      Bile Duct, Fibrosis                              5 [1.2]      4 [1.0]                                                         
      Bile Duct, Hyperplasia                          45 [2.5]     16 [1.4]                                                         
      Bile Duct, Inflammation                          1 [2.0]                                                                      
      Hepatocyte, Degeneration                         7 [2.3]                                                                      
      Hepatocyte, Hypertrophy                         49 [3.4]     21 [1.4]                                                         
      Oval Cell, Hyperplasia                          40 [2.2]      1 [1.0]                                                         
      Portal, Fibrosis                                10 [2.1]                                                                      
      Serosa, Inflammation                             1 [1.0]                                                                      
   Mesentery                                          (11)                                                                          
      Inflammation, Chronic Active                     3 [2.7]                                                                      
      Artery, Inflammation, Chronic Active             7 [2.7]                                                                      
      Fat, Necrosis                                    1 [2.0]                                                                      
   Oral Mucosa                                        (11)         (6)                                                              
      Gingival, Cyst, Squamous                         1 [2.0]                                                                      
      Gingival, Hyperplasia, Squamous                  3 [2.7]      3 [2.3]                                                         
      Pharyngeal, Hyperplasia, Squamous                             1 [4.0]                                                         
   Pancreas                                           (51)         (48)                                                             
      Basophilic Focus                                              1                                                               
      Cyst                                             1 [2.0]                                                                      
      Inflammation, Chronic Active                    13 [2.2]      4 [1.5]                                                         
      Necrosis                                         1 [2.0]                                                                      
      Acinus, Atrophy                                 18 [2.1]      7 [1.4]                                                         
      Acinus, Vacuolization Cytoplasmic               23 [1.4]      1 [1.0]                                                         
      Artery, Inflammation, Chronic Active            11 [2.9]      1 [2.0]                                                         
      Duct, Dilatation                                 2 [4.0]                                                                      
      Duct, Hyperplasia                                1 [2.0]                                                                      
   Salivary Glands                                    (51)         (49)                                                             
      Atrophy                                                       1 [2.0]                                                         
      Cyst                                                          2 [3.0]                                                         
      Inflammation, Acute                              1 [2.0]                                                                      
   Stomach, Forestomach                               (53)         (50)                                                             
      Edema                                                         2 [2.0]                                                         
      Hyperkeratosis                                   2 [1.5]                                                                      
      Hyperplasia, Squamous                            8 [1.9]      2 [1.5]                                                         
      Mineralization                                   2 [2.0]                                                                      
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Average severity grade (1-minimal;2-mild;3-moderate;4-marked)                                                                    
                                                                                                                                    
                                                             Page   12                                                              
                                                                                                                                   
NTP Experiment-Test: 96007-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT18  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 10/01/03    
Route: GAVAGE                                   TOXIC EQUIVALENCY FACTOR EVALUATION (PCB-126)                     Time: 12:01:01    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         SPRAGUE-DAWLEY RATS FEMALE                   1000         1000 NG/                                                         
                                                      NG/KG        KG/STOP                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Ulcer                                            2 [2.0]                                                                      
   Stomach, Glandular                                 (53)         (50)                                                             
      Erosion                                                       1 [2.0]                                                         
      Inflammation, Chronic Active                     1 [1.0]                                                                      
      Mineralization                                   1 [2.0]                                                                      
      Artery, Inflammation, Chronic Active             1 [2.0]                                                                      
      Glands, Ectasia                                  1 [2.0]                                                                      
      Glands, Hyperplasia                              1 [2.0]                                                                      
   Tooth                                              (19)         (12)                                                             
      Peridontal Tissue, Fibrosis                      1 [3.0]      1 [3.0]                                                         
      Peridontal Tissue, Inflammation, Suppurative    18 [1.6]     11 [1.6]                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Blood Vessel                                       (53)         (50)                                                             
      Aorta, Mineralization                                         1 [2.0]                                                         
   Heart                                              (51)         (50)                                                             
      Cardiomyopathy                                  32 [1.2]     15 [1.2]                                                         
      Mineralization                                                1 [2.0]                                                         
      Thrombosis                                       1 [3.0]      1 [2.0]                                                         
      Artery, Inflammation, Chronic Active                          1 [1.0]                                                         
      Endocardium, Myocardium, Inflammation, Acute     1 [3.0]                                                                      
      Epicardium, Inflammation, Chronic Active         1 [2.0]                                                                      
      Epicardium, Inflammation, Suppurative                         1 [4.0]                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (53)         (50)                                                             
      Angiectasis                                      1 [2.0]     14 [1.7]                                                         
      Atrophy                                         30 [2.2]      9 [1.7]                                                         
      Degeneration, Cystic                            10 [2.2]     20 [2.4]                                                         
      Hyperplasia                                     24 [2.5]     26 [2.0]                                                         
      Hypertrophy                                     41 [1.8]     42 [2.4]                                                         
      Inflammation, Suppurative                                     1 [2.0]                                                         
      Mineralization                                   1 [2.0]                                                                      
      Necrosis                                         2 [1.5]      2 [1.5]                                                         
      Vacuolization Cytoplasmic                       17 [1.9]      6 [1.5]                                                         
   Adrenal Medulla                                    (53)         (50)                                                             
      Hyperplasia                                      1 [2.0]      9 [1.4]                                                         
   Parathyroid Gland                                  (46)         (44)                                                             
      Cyst                                                          1 [2.0]                                                         
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Average severity grade (1-minimal;2-mild;3-moderate;4-marked)                                                                    
                                                                                                                                    
                                                             Page   13                                                              
                                                                                                                                   
NTP Experiment-Test: 96007-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT18  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 10/01/03    
Route: GAVAGE                                   TOXIC EQUIVALENCY FACTOR EVALUATION (PCB-126)                     Time: 12:01:01    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         SPRAGUE-DAWLEY RATS FEMALE                   1000         1000 NG/                                                         
                                                      NG/KG        KG/STOP                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ENDOCRINE SYSTEM - CONT                                                                                                             
      Hyperplasia                                                   2 [1.5]                                                         
   Pituitary Gland                                    (53)         (48)                                                             
      Angiectasis                                      9 [2.1]     14 [2.3]                                                         
      Cyst                                             1 [1.0]      1 [3.0]                                                         
      Cytoplasmic Alteration                                        1 [2.0]                                                         
      Pars Distalis, Hyperplasia                      17 [1.9]     17 [2.0]                                                         
   Thyroid Gland                                      (48)         (47)                                                             
      Angiectasis                                                   1 [2.0]                                                         
      Atrophy                                          1 [4.0]                                                                      
      Infiltration Cellular, Lymphocyte                1 [2.0]                                                                      
      C-Cell, Hyperplasia                             19 [1.7]     18 [1.8]                                                         
      Follicular Cell, Hyperplasia                     1 [4.0]                                                                      
      Follicular Cell, Hypertrophy                    16 [1.3]     22 [1.4]                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Clitoral Gland                                     (51)         (48)                                                             
      Inflammation                                    22 [1.3]     32 [1.6]                                                         
      Duct, Cyst                                      45 [2.3]     39 [1.9]                                                         
   Ovary                                              (53)         (50)                                                             
      Atrophy                                         33 [3.9]     47 [4.0]                                                         
      Cyst                                            11 [2.5]     17 [2.3]                                                         
   Oviduct                                            (1)          (2)                                                              
      Inflammation, Suppurative                        1 [3.0]      2 [3.0]                                                         
   Uterus                                             (53)         (50)                                                             
      Hemorrhage                                       1 [2.0]                                                                      
      Inflammation, Chronic Active                                  1 [4.0]                                                         
      Inflammation, Suppurative                        4 [2.5]     11 [2.2]                                                         
      Metaplasia, Squamous                            11 [2.4]     28 [2.0]                                                         
      Endometrium, Hyperplasia, Cystic                 9 [1.8]     31 [2.0]                                                         
      Epithelium, Hyperplasia                                       1 [2.0]                                                         
   Vagina                                             (1)                                                                           
      Cyst                                             1 [3.0]                                                                      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Average severity grade (1-minimal;2-mild;3-moderate;4-marked)                                                                    
                                                                                                                                    
                                                             Page   14                                                              
                                                                                                                                   
NTP Experiment-Test: 96007-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT18  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 10/01/03    
Route: GAVAGE                                   TOXIC EQUIVALENCY FACTOR EVALUATION (PCB-126)                     Time: 12:01:01    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         SPRAGUE-DAWLEY RATS FEMALE                   1000         1000 NG/                                                         
                                                      NG/KG        KG/STOP                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
HEMATOPOIETIC SYSTEM - CONT                                                                                                         
   Bone Marrow                                        (53)         (50)                                                             
      Atrophy                                          1 [3.0]                                                                      
      Hyperplasia                                     46 [3.3]     34 [3.1]                                                         
   Lymph Node                                         (12)         (2)                                                              
      Iliac, Ectasia                                                1 [2.0]                                                         
      Mediastinal, Angiectasis                         1 [2.0]                                                                      
      Mediastinal, Ectasia                             5 [1.8]                                                                      
      Mediastinal, Hemorrhage                          6 [2.0]                                                                      
      Mediastinal, Hyperplasia, Lymphoid               1 [2.0]                                                                      
      Mediastinal, Pigmentation                        2 [2.0]                                                                      
      Pancreatic, Hemorrhage                           1 [1.0]                                                                      
   Lymph Node, Mandibular                             (51)         (49)                                                             
      Atrophy                                          1 [3.0]                                                                      
      Ectasia                                          3 [2.3]      3 [2.3]                                                         
      Hemorrhage                                       1 [2.0]                                                                      
      Hyperplasia, Lymphoid                            1 [2.0]                                                                      
      Hyperplasia, Plasma Cell                        15 [2.1]     21 [2.3]                                                         
   Lymph Node, Mesenteric                             (53)         (50)                                                             
      Atrophy                                          1 [3.0]      2 [1.5]                                                         
      Ectasia                                          1 [2.0]                                                                      
      Hemorrhage                                       2 [1.5]                                                                      
      Hyperplasia, Histiocytic                         1 [2.0]      1 [2.0]                                                         
      Hyperplasia, Lymphoid                            2 [2.0]                                                                      
      Hyperplasia, Plasma Cell                                      1 [2.0]                                                         
   Spleen                                             (52)         (50)                                                             
      Hematopoietic Cell Proliferation                37 [1.6]     37 [1.5]                                                         
      Hyperplasia, Lymphoid                            3 [2.0]                                                                      
      Pigmentation                                    50 [1.3]     50 [1.6]                                                         
      Lymphoid Follicle, Atrophy                       6 [2.3]      4 [2.5]                                                         
      Red Pulp, Atrophy                                2 [2.5]                                                                      
   Thymus                                             (44)         (43)                                                             
      Atrophy                                         41 [3.5]     39 [3.0]                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (53)         (50)                                                             
      Cyst                                             1 [3.0]     13 [2.7]                                                         
      Hyperplasia                                      9 [1.4]     22 [1.1]                                                         
   Skin                                               (53)         (50)                                                             
      Cyst, Squamous                                   1 [3.0]      2 [2.5]                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Average severity grade (1-minimal;2-mild;3-moderate;4-marked)                                                                    
                                                                                                                                    
                                                             Page   15                                                              
                                                                                                                                   
NTP Experiment-Test: 96007-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT18  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 10/01/03    
Route: GAVAGE                                   TOXIC EQUIVALENCY FACTOR EVALUATION (PCB-126)                     Time: 12:01:01    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         SPRAGUE-DAWLEY RATS FEMALE                   1000         1000 NG/                                                         
                                                      NG/KG        KG/STOP                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Skeletal Muscle                                    (1)                                                                           
      Inflammation, Chronic Active                     1 [2.0]                                                                      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (53)         (50)                                                             
      Hemorrhage                                       1 [2.0]                                                                      
      Inflammation, Focal, Suppurative                 1 [3.0]                                                                      
      Necrosis, Focal                                  1 [3.0]                                                                      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Lung                                               (51)         (50)                                                             
      Hemorrhage                                       1 [2.0]      1 [2.0]                                                         
      Infiltration Cellular, Histiocyte               42 [1.5]     42 [1.5]                                                         
      Inflammation, Chronic Active                     2 [2.5]                                                                      
      Metaplasia, Squamous                             4 [1.8]                                                                      
      Mineralization                                   1 [2.0]      1 [2.0]                                                         
      Alveolar Epithelium, Metaplasia, Bronchiolar    40 [1.9]     32 [1.5]                                                         
      Serosa, Inflammation, Suppurative                             1 [3.0]                                                         
   Nose                                               (53)         (50)                                                             
      Goblet Cell, Respiratory Epithelium,                                                                                          
        Hyperplasia                                    1 [2.0]                                                                      
      Nasolacrimal Duct, Inflammation                  1 [3.0]      1 [3.0]                                                         
      Nasolacrimal Duct, Respiratory Epithelium,                                                                                    
         Hyperplasia                                   1 [3.0]                                                                      
      Nasopharyngeal Duct, Respiratory Epithelium,                                                                                  
         Hyperplasia                                   1 [3.0]                                                                      
      Respiratory Epithelium, Hyperplasia              1 [2.0]      1 [2.0]                                                         
      Turbinate, Cyst                                  1 [2.0]                                                                      
      Turbinate, Inflammation, Suppurative             4 [2.3]      1 [1.0]                                                         
      Vomeronasal Organ, Vacuolization Cytoplasmic     1 [2.0]                                                                      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                (52)         (50)                                                             
      Anterior Chamber, Inflammation, Suppurative      1 [3.0]      1 [3.0]                                                         
      Cornea, Inflammation, Suppurative                2 [2.5]      1 [3.0]                                                         
      Optic Nerve, Degeneration                        1 [2.0]                                                                      
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Average severity grade (1-minimal;2-mild;3-moderate;4-marked)                                                                    
                                                                                                                                    
                                                             Page   16                                                              
                                                                                                                                   
NTP Experiment-Test: 96007-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT18  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 10/01/03    
Route: GAVAGE                                   TOXIC EQUIVALENCY FACTOR EVALUATION (PCB-126)                     Time: 12:01:01    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         SPRAGUE-DAWLEY RATS FEMALE                   1000         1000 NG/                                                         
                                                      NG/KG        KG/STOP                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
SPECIAL SENSES SYSTEM - CONT                                                                                                        
      Retina, Atrophy                                  4 [2.5]                                                                      
   Harderian Gland                                    (52)         (50)                                                             
      Inflammation                                     6 [1.2]      9 [1.1]                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (53)         (50)                                                             
      Casts Protein                                    2 [1.5]      3 [1.7]                                                         
      Inflammation, Suppurative                        2 [2.0]                                                                      
      Mineralization                                  37 [1.0]     45 [1.0]                                                         
      Necrosis                                         1 [3.0]                                                                      
      Nephropathy                                     47 [2.1]     38 [1.4]                                                         
      Papilla, Necrosis                                1 [2.0]                                                                      
      Pelvis, Dilatation                               2 [3.5]      1 [2.0]                                                         
      Pelvis, Hemorrhage                               1 [3.0]                                                                      
      Pelvis, Inflammation, Chronic Active             1 [3.0]      1 [3.0]                                                         
      Pelvis, Metaplasia, Squamous                     1 [2.0]                                                                      
      Transitional Epithelium, Hyperplasia            11 [2.0]      2 [2.0]                                                         
   Ureter                                             (3)                                                                           
      Inflammation                                     1 [2.0]                                                                      
      Metaplasia, Squamous                             2 [2.5]                                                                      
      Mineralization                                   2 [3.5]                                                                      
      Transitional Epithelium, Hyperplasia             3 [3.0]                                                                      
   Urinary Bladder                                    (53)         (50)                                                             
      Inflammation                                     6 [1.5]      3 [1.3]                                                         
      Metaplasia, Squamous                             1 [2.0]                                                                      
      Transitional Epithelium, Hyperplasia             2 [3.0]                                                                      
                                                                                                                                    
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Average severity grade (1-minimal;2-mild;3-moderate;4-marked)                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page   17                                                              
                                                                                                                                   
                             ------------------------------------------------------------                                           
                             ----------              END OF REPORT             ----------                                           
                             ------------------------------------------------------------                                           
NTP is located at the National Institute of Environmental Health Sciences, part of the National Institutes of Health.