National Toxicology Program

National Toxicology Program
https://ntp.niehs.nih.gov/go/5314

TDMS Study 96007-03 Pathology Tables

NTP Experiment-Test: 96007-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                             TOXIC EQUIVALENCY FACTOR EVALUATION (TCDD)                        Date: 09/30/03
Route: GAVAGE                                                                                                     Time: 08:37:05

                                                         FINAL # 3 RATS




       Facility:  Battelle Columbus Laboratory

       Chemical CAS #:  1746-01-6

       Lock Date:  06/28/01

       Cage Range:  All

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

       Removal Date Range:     All

       Treatment Groups:       Include All

































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

                                                              Page   1


NTP Experiment-Test: 96007-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                             TOXIC EQUIVALENCY FACTOR EVALUATION (TCDD)                        Date: 09/30/03    
Route: GAVAGE                                                                                                     Time: 08:37:05    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         SPRAGUE-DAWLEY RATS FEMALE                0 NG/KG      3 NG/KG      10 NG/KG     22 NG/KG     46 NG/KG     100             
                                                                                                                    NG/KG           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
DISPOSITION SUMMARY                                                                                                                 
                                                                                                                                    
  Animals Initially In Study                          98           98           98           98           98           98           
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                19           27           15           19           17           17           
    Natural Death                                      9            6           10           15           14           15           
    Dosing Accident                                                              5                                                  
  Survivors                                                                                                                         
    Terminal Sacrifice                                25           21           23           19           22           21           
                                                                                                                                    
  Animals Examined Microscopically                    53           54           53           53           53           53           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Esophagus                                          (52)         (54)         (53)         (52)         (53)         (53)         
      Hemorrhage                                                                 1 (2%)                                             
      Perforation                                                                2 (4%)                                             
      Muscularis, Inflammation                         1 (2%)       2 (4%)       1 (2%)       1 (2%)       2 (4%)                   
      Periesophageal Tissue, Inflammation                                        3 (6%)                                             
   Intestine Large, Colon                             (52)         (53)         (53)         (53)         (53)         (51)         
      Parasite Metazoan                                1 (2%)       2 (4%)       1 (2%)                                 2 (4%)      
   Intestine Large, Rectum                            (52)         (54)         (53)         (52)         (53)         (53)         
      Parasite Metazoan                                6 (12%)      4 (7%)                                 2 (4%)       1 (2%)      
   Intestine Small, Duodenum                          (53)         (54)         (53)         (52)         (53)         (53)         
      Cyst                                                                                                              1 (2%)      
      Ulcer                                                         1 (2%)                                                          
      Epithelium, Hyperplasia                                                    1 (2%)                                             
   Liver                                              (53)         (54)         (53)         (53)         (53)         (53)         
      Angiectasis                                      2 (4%)       1 (2%)       1 (2%)                    3 (6%)       5 (9%)      
      Basophilic Focus                                 8 (15%)      6 (11%)      8 (15%)      7 (13%)      3 (6%)       3 (6%)      
      Basophilic Focus, Multiple                       4 (8%)       3 (6%)       5 (9%)       1 (2%)       2 (4%)       5 (9%)      
      Cholangiofibrosis                                1 (2%)       1 (2%)       2 (4%)       1 (2%)      11 (21%)     31 (58%)     
      Clear Cell Focus                                 4 (8%)       1 (2%)       1 (2%)       2 (4%)       1 (2%)       1 (2%)      
      Clear Cell Focus, Multiple                       1 (2%)                                 2 (4%)       1 (2%)       1 (2%)      
      Congestion                                       2 (4%)                                                           2 (4%)      
      Cytoplasmic Alteration                                                                                            2 (4%)      
      Degeneration, Cystic                                                                    2 (4%)                    4 (8%)      
      Eosinophilic Focus                               8 (15%)      6 (11%)      7 (13%)     10 (19%)      5 (9%)       2 (4%)      
      Eosinophilic Focus, Multiple                     3 (6%)       8 (15%)     14 (26%)     17 (32%)     22 (42%)     42 (79%)     
      Fatty Change, Diffuse                                         2 (4%)      12 (23%)     17 (32%)     30 (57%)     48 (91%)     
      Fatty Change, Focal                              2 (4%)       6 (11%)      4 (8%)       4 (8%)       1 (2%)       2 (4%)      
      Hematopoietic Cell Proliferation                 1 (2%)       2 (4%)       2 (4%)       4 (8%)       2 (4%)       2 (4%)      
      Hemorrhage                                                                                           1 (2%)                   
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page    2                                                              
                                                                                                                                   
NTP Experiment-Test: 96007-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                             TOXIC EQUIVALENCY FACTOR EVALUATION (TCDD)                        Date: 09/30/03    
Route: GAVAGE                                                                                                     Time: 08:37:05    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         SPRAGUE-DAWLEY RATS FEMALE                0 NG/KG      3 NG/KG      10 NG/KG     22 NG/KG     46 NG/KG     100             
                                                                                                                    NG/KG           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Hepatodiaphragmatic Nodule                                    2 (4%)                    1 (2%)       2 (4%)                   
      Hyperplasia, Nodular                                                                    3 (6%)       7 (13%)     36 (68%)     
      Inflammation                                    33 (62%)     46 (85%)     47 (89%)     50 (94%)     52 (98%)     49 (92%)     
      Mitotic Alteration                                                                      1 (2%)       1 (2%)                   
      Mixed Cell Focus                                 4 (8%)       8 (15%)      8 (15%)                   2 (4%)       4 (8%)      
      Mixed Cell Focus, Multiple                      26 (49%)     11 (20%)     21 (40%)     23 (43%)     28 (53%)     17 (32%)     
      Necrosis                                         1 (2%)       4 (7%)       4 (8%)       8 (15%)     10 (19%)     17 (32%)     
      Pigmentation                                     4 (8%)       9 (17%)     34 (64%)     48 (91%)     52 (98%)     53 (100%)    
      Thrombosis                                                                                                        1 (2%)      
      Toxic Hepatopathy                                             2 (4%)       8 (15%)     30 (57%)     45 (85%)     53 (100%)    
      Artery, Inflammation, Chronic Active                                                                              2 (4%)      
      Bile Duct, Cyst                                  3 (6%)       1 (2%)       2 (4%)       2 (4%)                   21 (40%)     
      Bile Duct, Fibrosis                                           2 (4%)                    1 (2%)       3 (6%)       4 (8%)      
      Bile Duct, Hyperplasia                           5 (9%)       4 (7%)       7 (13%)     22 (42%)     40 (75%)     53 (100%)    
      Centrilobular, Degeneration                      2 (4%)       2 (4%)                    4 (8%)       3 (6%)       5 (9%)      
      Hepatocyte, Hypertrophy                                      19 (35%)     19 (36%)     42 (79%)     41 (77%)     52 (98%)     
      Hepatocyte, Multinucleated                                                16 (30%)     26 (49%)     36 (68%)     51 (96%)     
      Hepatocyte, Centrilobular, Atrophy                                                                   1 (2%)                   
      Oval Cell, Hyperplasia                                        4 (7%)       3 (6%)      20 (38%)     38 (72%)     53 (100%)    
      Portal, Fibrosis                                                                                     5 (9%)      27 (51%)     
   Mesentery                                          (2)          (2)                       (1)          (6)          (8)          
      Metaplasia, Osseous                              1 (50%)                                                                      
      Artery, Inflammation, Chronic Active                          1 (50%)                                4 (67%)      7 (88%)     
      Fat, Necrosis                                                 1 (50%)                   1 (100%)     1 (17%)      1 (13%)     
      Vein, Thrombosis                                 1 (50%)                                                                      
   Oral Mucosa                                        (2)          (9)          (16)         (16)         (22)         (29)         
      Gingival, Hyperplasia, Squamous                  1 (50%)      7 (78%)     14 (88%)     13 (81%)     15 (68%)     16 (55%)     
   Pancreas                                           (51)         (54)         (52)         (53)         (52)         (51)         
      Hemorrhage                                                                                                        1 (2%)      
      Inflammation, Acute                                                                     1 (2%)                                
      Inflammation, Chronic Active                                               2 (4%)       2 (4%)       3 (6%)       6 (12%)     
      Necrosis                                                                                1 (2%)                    1 (2%)      
      Acinus, Atrophy                                  1 (2%)       2 (4%)       4 (8%)       4 (8%)       4 (8%)       9 (18%)     
      Acinus, Hyperplasia                              2 (4%)                                 1 (2%)       2 (4%)                   
      Acinus, Vacuolization Cytoplasmic                1 (2%)                                 1 (2%)      15 (29%)     42 (82%)     
      Artery, Inflammation, Chronic Active                          1 (2%)       1 (2%)       2 (4%)       2 (4%)       7 (14%)     
   Salivary Glands                                    (51)         (54)         (52)         (50)         (51)         (52)         
      Atrophy                                                                                 2 (4%)       1 (2%)                   
      Inflammation                                                               2 (4%)       3 (6%)                    1 (2%)      
      Mineralization                                   1 (2%)                                                                       
   Stomach, Forestomach                               (53)         (54)         (53)         (53)         (53)         (53)         
      Cyst, Squamous                                                             1 (2%)                                             
      Edema                                                                                   1 (2%)                    1 (2%)      
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page    3                                                              
                                                                                                                                   
NTP Experiment-Test: 96007-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                             TOXIC EQUIVALENCY FACTOR EVALUATION (TCDD)                        Date: 09/30/03    
Route: GAVAGE                                                                                                     Time: 08:37:05    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         SPRAGUE-DAWLEY RATS FEMALE                0 NG/KG      3 NG/KG      10 NG/KG     22 NG/KG     46 NG/KG     100             
                                                                                                                    NG/KG           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Erosion                                                                    1 (2%)                    1 (2%)                   
      Hyperkeratosis                                   1 (2%)       1 (2%)       1 (2%)       1 (2%)       2 (4%)       3 (6%)      
      Hyperplasia, Squamous                            3 (6%)       4 (7%)       4 (8%)       2 (4%)       7 (13%)     11 (21%)     
      Inflammation                                     1 (2%)       1 (2%)       2 (4%)                    2 (4%)       5 (9%)      
      Mineralization                                                             1 (2%)                                             
      Necrosis                                                                                                          1 (2%)      
      Ulcer                                            2 (4%)       1 (2%)                    1 (2%)       1 (2%)       4 (8%)      
   Stomach, Glandular                                 (53)         (54)         (53)         (53)         (53)         (53)         
      Diverticulum                                                               1 (2%)                                             
      Erosion                                          1 (2%)                                                                       
      Metaplasia                                                                                           1 (2%)                   
      Mineralization                                   3 (6%)                                 1 (2%)       3 (6%)                   
      Ulcer                                                                                                             2 (4%)      
   Tooth                                              (16)         (16)         (12)         (13)         (14)         (18)         
      Peridontal Tissue, Fibrosis                      1 (6%)                                                                       
      Peridontal Tissue, Inflammation                 15 (94%)     16 (100%)    12 (100%)    13 (100%)    14 (100%)    18 (100%)    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Blood Vessel                                       (53)         (54)         (53)         (53)         (53)         (53)         
      Thrombosis                                                                 1 (2%)                                             
      Aorta, Mineralization                            1 (2%)       1 (2%)                                 1 (2%)                   
   Heart                                              (53)         (54)         (53)         (52)         (53)         (52)         
      Cardiomyopathy                                  10 (19%)     12 (22%)     22 (42%)     25 (48%)     32 (60%)     36 (69%)     
      Mineralization                                   1 (2%)                                              1 (2%)                   
      Artery, Inflammation                                                                                              1 (2%)      
      Artery, Mineralization                                        1 (2%)                                                          
      Artery, Thrombosis                                                                                                1 (2%)      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (53)         (54)         (53)         (53)         (53)         (53)         
      Angiectasis                                     11 (21%)     21 (39%)     18 (34%)     17 (32%)     17 (32%)     11 (21%)     
      Atrophy                                          2 (4%)                    4 (8%)       5 (9%)       5 (9%)      27 (51%)     
      Degeneration, Cystic                            11 (21%)     15 (28%)     21 (40%)     18 (34%)     17 (32%)     17 (32%)     
      Hyperplasia                                     16 (30%)     16 (30%)     18 (34%)     25 (47%)     29 (55%)     30 (57%)     
      Hypertrophy                                     41 (77%)     43 (80%)     46 (87%)     40 (75%)     45 (85%)     47 (89%)     
      Inflammation, Chronic Active                     1 (2%)                                                                       
      Inflammation, Suppurative                        1 (2%)                                                                       
      Mineralization                                                                                                    1 (2%)      
      Necrosis                                                      1 (2%)       2 (4%)       1 (2%)       3 (6%)       1 (2%)      
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page    4                                                              
                                                                                                                                   
NTP Experiment-Test: 96007-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                             TOXIC EQUIVALENCY FACTOR EVALUATION (TCDD)                        Date: 09/30/03    
Route: GAVAGE                                                                                                     Time: 08:37:05    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         SPRAGUE-DAWLEY RATS FEMALE                0 NG/KG      3 NG/KG      10 NG/KG     22 NG/KG     46 NG/KG     100             
                                                                                                                    NG/KG           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ENDOCRINE SYSTEM - CONT                                                                                                             
      Thrombosis                                                                              1 (2%)                                
      Vacuolization Cytoplasmic                       11 (21%)      7 (13%)     12 (23%)     21 (40%)     18 (34%)     15 (28%)     
   Adrenal Medulla                                    (53)         (54)         (53)         (53)         (53)         (53)         
      Angiectasis                                                   1 (2%)       2 (4%)       1 (2%)                                
      Hyperplasia                                     19 (36%)     10 (19%)     18 (34%)      7 (13%)     10 (19%)      9 (17%)     
      Inflammation, Suppurative                                                               1 (2%)                                
   Islets, Pancreatic                                 (51)         (54)         (53)         (53)         (52)         (52)         
      Hyperplasia                                                                1 (2%)       1 (2%)                                
   Parathyroid Gland                                  (46)         (47)         (47)         (44)         (45)         (45)         
      Fibrosis                                                                   1 (2%)                                             
      Hyperplasia                                      1 (2%)                                                                       
   Pituitary Gland                                    (53)         (54)         (52)         (53)         (53)         (52)         
      Angiectasis                                     25 (47%)     18 (33%)     25 (48%)     20 (38%)     21 (40%)      9 (17%)     
      Atypia Cellular                                  1 (2%)                                                                       
      Cyst                                             1 (2%)       1 (2%)                                              1 (2%)      
      Cytoplasmic Alteration                           1 (2%)                    1 (2%)       4 (8%)       3 (6%)                   
      Developmental Malformation                       1 (2%)                                                                       
      Inflammation, Chronic                                                                                             1 (2%)      
      Vacuolization Cytoplasmic                                     3 (6%)       1 (2%)       2 (4%)       2 (4%)                   
      Pars Distalis, Hyperplasia                      19 (36%)     19 (35%)     16 (31%)     21 (40%)     26 (49%)     19 (37%)     
      Pars Intermedia, Hyperplasia                     2 (4%)                                              1 (2%)       1 (2%)      
   Thyroid Gland                                      (52)         (54)         (53)         (51)         (53)         (52)         
      Angiectasis                                                   1 (2%)       1 (2%)       1 (2%)       4 (8%)       1 (2%)      
      Cyst                                             1 (2%)                                 1 (2%)                    1 (2%)      
      Inflammation, Chronic Active                                               1 (2%)                                             
      Inflammation, Suppurative                                                  1 (2%)                                             
      C-Cell, Hyperplasia                             19 (37%)     17 (31%)     22 (42%)     19 (37%)     16 (30%)     23 (44%)     
      Follicular Cell, Hyperplasia                     2 (4%)       2 (4%)                                                          
      Follicular Cell, Hypertrophy                     3 (6%)       4 (7%)       4 (8%)       7 (14%)     10 (19%)     17 (33%)     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Clitoral Gland                                     (50)         (52)         (53)         (52)         (51)         (53)         
      Hyperplasia, Basal Cell                          1 (2%)                    1 (2%)                                             
      Inflammation                                    41 (82%)     40 (77%)     35 (66%)     34 (65%)     28 (55%)     26 (49%)     
      Duct, Cyst                                      34 (68%)     37 (71%)     41 (77%)     42 (81%)     41 (80%)     48 (91%)     
   Ovary                                              (51)         (53)         (53)         (53)         (53)         (53)         
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page    5                                                              
                                                                                                                                   
NTP Experiment-Test: 96007-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                             TOXIC EQUIVALENCY FACTOR EVALUATION (TCDD)                        Date: 09/30/03    
Route: GAVAGE                                                                                                     Time: 08:37:05    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         SPRAGUE-DAWLEY RATS FEMALE                0 NG/KG      3 NG/KG      10 NG/KG     22 NG/KG     46 NG/KG     100             
                                                                                                                    NG/KG           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
GENITAL SYSTEM - CONT                                                                                                               
      Atrophy                                         49 (96%)     46 (87%)     50 (94%)     44 (83%)     50 (94%)     31 (58%)     
      Congestion                                                                              1 (2%)                                
      Cyst                                            14 (27%)     16 (30%)     13 (25%)     15 (28%)     14 (26%)     13 (25%)     
      Fibrosis                                                                   1 (2%)                    1 (2%)                   
      Inflammation, Chronic Active                                                            1 (2%)                    1 (2%)      
      Inflammation, Suppurative                                                               1 (2%)       1 (2%)                   
      Artery, Inflammation, Chronic Active                                                                              1 (2%)      
      Corpus Luteum, Cyst                                           1 (2%)                                                          
      Periovarian Tissue, Inflammation, Suppurative                                           1 (2%)                                
   Oviduct                                            (2)          (1)          (2)                       (1)          (1)          
      Inflammation                                     2 (100%)     1 (100%)     1 (50%)                                1 (100%)    
      Necrosis                                                                                             1 (100%)                 
      Epithelium, Hyperplasia                                                    1 (50%)                                            
   Uterus                                             (52)         (53)         (53)         (53)         (53)         (53)         
      Adenomyosis                                                                                          1 (2%)                   
      Cyst                                                                                                              1 (2%)      
      Hemorrhage                                       1 (2%)                                                           1 (2%)      
      Inflammation, Chronic Active                                  2 (4%)       3 (6%)                    3 (6%)       1 (2%)      
      Inflammation, Suppurative                        7 (13%)      6 (11%)     12 (23%)      9 (17%)     11 (21%)      5 (9%)      
      Metaplasia, Squamous                            29 (56%)     31 (58%)     28 (53%)     23 (43%)     32 (60%)     17 (32%)     
      Necrosis                                                                                1 (2%)                                
      Ulcer                                                                      1 (2%)                                             
      Cervix, Hyperplasia, Stromal                                  1 (2%)       1 (2%)       1 (2%)       1 (2%)                   
      Cervix, Inflammation, Suppurative                                                                    1 (2%)                   
      Endometrium, Adenomyosis                                                   1 (2%)                                             
      Endometrium, Hyperplasia, Cystic                30 (58%)     33 (62%)     35 (66%)     27 (51%)     31 (58%)     19 (36%)     
      Epithelium, Hyperplasia                                                                 1 (2%)                                
      Serosa, Inflammation, Chronic Active                                       1 (2%)                                             
   Vagina                                                          (1)          (1)          (3)          (3)          (1)          
      Cyst                                                                       1 (100%)                  1 (33%)                  
      Hyperplasia, Stromal                                          1 (100%)                                                        
      Inflammation                                                                            2 (67%)                               
      Necrosis                                                                                1 (33%)                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (53)         (54)         (53)         (53)         (53)         (53)         
      Atrophy                                                                                                           1 (2%)      
      Hyperplasia                                     36 (68%)     41 (76%)     32 (60%)     35 (66%)     37 (70%)     43 (81%)     
   Lymph Node                                         (2)          (6)          (3)          (5)          (6)          (9)          
      Deep Cervical, Hemorrhage                                                               1 (20%)                               
      Inguinal, Ectasia                                                                                    1 (17%)                  
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page    6                                                              
                                                                                                                                   
NTP Experiment-Test: 96007-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                             TOXIC EQUIVALENCY FACTOR EVALUATION (TCDD)                        Date: 09/30/03    
Route: GAVAGE                                                                                                     Time: 08:37:05    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         SPRAGUE-DAWLEY RATS FEMALE                0 NG/KG      3 NG/KG      10 NG/KG     22 NG/KG     46 NG/KG     100             
                                                                                                                    NG/KG           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
HEMATOPOIETIC SYSTEM - CONT                                                                                                         
      Lumbar, Ectasia                                  1 (50%)      2 (33%)      1 (33%)      2 (40%)                               
      Lumbar, Hemorrhage                                                                      1 (20%)                               
      Lumbar, Hyperplasia, Plasma Cell                              2 (33%)                   1 (20%)                               
      Lumbar, Pigmentation                                                                    1 (20%)                               
      Mediastinal, Congestion                                                                              1 (17%)                  
      Mediastinal, Ectasia                                                                                 1 (17%)      3 (33%)     
      Mediastinal, Hemorrhage                                       1 (17%)                   1 (20%)                   5 (56%)     
      Mediastinal, Hyperplasia                                                                             1 (17%)                  
      Mediastinal, Hyperplasia, Histiocytic                                      1 (33%)                   1 (17%)      1 (11%)     
      Mediastinal, Hyperplasia, Lymphoid                            1 (17%)                                                         
      Mediastinal, Hyperplasia, Plasma Cell                                                   1 (20%)                               
      Mediastinal, Pigmentation                                                  1 (33%)                                1 (11%)     
      Renal, Ectasia                                                1 (17%)                                                         
      Renal, Hyperplasia, Histiocytic                               1 (17%)                                                         
   Lymph Node, Mandibular                             (51)         (54)         (52)         (50)         (51)         (52)         
      Congestion                                       1 (2%)                                                                       
      Ectasia                                                                                              1 (2%)       6 (12%)     
      Hyperplasia, Lymphoid                                         3 (6%)       3 (6%)                                 2 (4%)      
      Hyperplasia, Plasma Cell                        25 (49%)     31 (57%)     23 (44%)     22 (44%)     15 (29%)     16 (31%)     
      Inflammation, Suppurative                                                                                         1 (2%)      
   Lymph Node, Mesenteric                             (52)         (53)         (53)         (53)         (53)         (51)         
      Atrophy                                                       1 (2%)                    1 (2%)                                
      Ectasia                                                                                                           1 (2%)      
      Hemorrhage                                                                                           1 (2%)                   
      Hyperplasia, Histiocytic                         1 (2%)                                              1 (2%)       2 (4%)      
      Hyperplasia, Plasma Cell                                                                             1 (2%)                   
   Spleen                                             (51)         (54)         (53)         (53)         (52)         (52)         
      Hematopoietic Cell Proliferation                46 (90%)     50 (93%)     38 (72%)     42 (79%)     44 (85%)     43 (83%)     
      Hyperplasia, Lymphoid                            1 (2%)                                                           4 (8%)      
      Necrosis                                                                   1 (2%)                                             
      Pigmentation                                    45 (88%)     49 (91%)     49 (92%)     51 (96%)     49 (94%)     47 (90%)     
      Lymphoid Follicle, Atrophy                       4 (8%)                    1 (2%)                    1 (2%)       1 (2%)      
   Thymus                                             (51)         (52)         (52)         (49)         (46)         (42)         
      Atrophy                                         36 (71%)     41 (79%)     44 (85%)     41 (84%)     44 (96%)     42 (100%)    
      Cyst                                                                                                 1 (2%)       1 (2%)      
      Hemorrhage                                       1 (2%)                    1 (2%)                                             
      Inflammation, Chronic Active                                                                         1 (2%)                   
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (53)         (54)         (53)         (53)         (53)         (53)         
      Cyst                                             4 (8%)       3 (6%)                    1 (2%)       1 (2%)       1 (2%)      
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page    7                                                              
                                                                                                                                   
NTP Experiment-Test: 96007-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                             TOXIC EQUIVALENCY FACTOR EVALUATION (TCDD)                        Date: 09/30/03    
Route: GAVAGE                                                                                                     Time: 08:37:05    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         SPRAGUE-DAWLEY RATS FEMALE                0 NG/KG      3 NG/KG      10 NG/KG     22 NG/KG     46 NG/KG     100             
                                                                                                                    NG/KG           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
INTEGUMENTARY SYSTEM - CONT                                                                                                         
      Hyperplasia                                     25 (47%)     21 (39%)     24 (45%)     22 (42%)     18 (34%)     16 (30%)     
      Inflammation, Chronic Active                                                                         1 (2%)                   
      Inflammation, Granulomatous                      1 (2%)       1 (2%)       1 (2%)                                 1 (2%)      
   Skin                                               (53)         (54)         (53)         (53)         (53)         (53)         
      Cyst Epithelial Inclusion                        1 (2%)                                                           2 (4%)      
      Hemorrhage                                                                 1 (2%)                                             
      Hyperplasia, Squamous                                                      1 (2%)                    1 (2%)                   
      Inflammation, Chronic Active                                               2 (4%)                                 1 (2%)      
      Necrosis                                                                   1 (2%)                                             
      Ulcer                                                                      1 (2%)                    1 (2%)                   
      Epidermis, Inflammation                                                                                           1 (2%)      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (53)         (54)         (53)         (53)         (53)         (53)         
      Fracture                                                                                                          1 (2%)      
      Maxilla, Inflammation, Focal, Suppurative                     1 (2%)                                                          
   Skeletal Muscle                                                              (1)          (2)                                    
      Hemorrhage                                                                              1 (50%)                               
      Inflammation, Chronic Active                                                            1 (50%)                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (53)         (54)         (53)         (53)         (53)         (53)         
      Hemorrhage                                                                 1 (2%)                                             
      Hydrocephalus                                                 1 (2%)       1 (2%)                                             
      Inflammation, Suppurative                                                                            1 (2%)                   
      Mineralization                                                1 (2%)       1 (2%)                    2 (4%)       2 (4%)      
      Vacuolization Cytoplasmic, Focal                                           1 (2%)                                             
      Artery, Thrombosis                                                                                   1 (2%)                   
      Cerebellum, Developmental Malformation           1 (2%)                                                                       
      Cerebellum, Necrosis                                                       1 (2%)                                             
      Glial Cell, Hyperplasia                                       1 (2%)                                              1 (2%)      
   Spinal Cord                                                                  (1)                                                 
      Gliosis                                                                    1 (100%)                                           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Lung                                               (53)         (54)         (53)         (52)         (53)         (52)         
      Congestion                                                                 2 (4%)                                             
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page    8                                                              
                                                                                                                                   
NTP Experiment-Test: 96007-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                             TOXIC EQUIVALENCY FACTOR EVALUATION (TCDD)                        Date: 09/30/03    
Route: GAVAGE                                                                                                     Time: 08:37:05    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         SPRAGUE-DAWLEY RATS FEMALE                0 NG/KG      3 NG/KG      10 NG/KG     22 NG/KG     46 NG/KG     100             
                                                                                                                    NG/KG           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
RESPIRATORY SYSTEM - CONT                                                                                                           
      Edema                                                                      2 (4%)                    1 (2%)                   
      Hemorrhage                                                    1 (2%)                                              2 (4%)      
      Infiltration Cellular, Histiocyte               41 (77%)     46 (85%)     43 (81%)     43 (83%)     49 (92%)     50 (96%)     
      Inflammation, Chronic Active                                                                                      1 (2%)      
      Inflammation, Granulomatous                      2 (4%)       1 (2%)       2 (4%)       2 (4%)                                
      Inflammation, Suppurative                        1 (2%)                                 2 (4%)                                
      Metaplasia, Squamous                             1 (2%)                                              5 (9%)       6 (12%)     
      Mineralization                                   1 (2%)                                              1 (2%)       1 (2%)      
      Necrosis                                                                                1 (2%)                    1 (2%)      
      Pigmentation                                                  1 (2%)                                                          
      Alveolar Epithelium, Hyperplasia                12 (23%)                                                                      
      Alveolar Epithelium, Metaplasia, Bronchiolar     2 (4%)      19 (35%)     33 (62%)     35 (67%)     45 (85%)     46 (88%)     
      Bronchiole, Dilatation                                                     1 (2%)                                             
      Serosa, Inflammation, Focal, Suppurative                                                1 (2%)                                
   Nose                                               (53)         (54)         (53)         (53)         (53)         (53)         
      Cyst, Squamous                                                                                       1 (2%)                   
      Inflammation                                     2 (4%)                                 3 (6%)       5 (9%)       4 (8%)      
      Goblet Cell, Septum, Hyperplasia                                                                     1 (2%)                   
      Nasolacrimal Duct, Inflammation                  2 (4%)                                                                       
      Nasolacrimal Duct, Respiratory Epithelium,                                                                                    
         Hyperplasia                                                                                       1 (2%)                   
      Nasopharyngeal Duct, Inflammation                                                       1 (2%)                    1 (2%)      
      Nasopharyngeal Duct, Necrosis                                                           1 (2%)                                
      Olfactory Epithelium, Degeneration                                                                   1 (2%)                   
      Olfactory Epithelium, Inflammation                                                                   1 (2%)       1 (2%)      
      Respiratory Epithelium, Cyst                                                                         2 (4%)                   
      Respiratory Epithelium, Hyperplasia                                                     1 (2%)       2 (4%)                   
      Septum, Hyperplasia, Squamous                                                                                     1 (2%)      
      Septum, Inflammation                                                                                              2 (4%)      
      Squamous Epithelium, Inflammation,                                                                                            
        Suppurative                                    1 (2%)                                                                       
      Turbinate, Hyperplasia, Squamous                                                                                  1 (2%)      
      Turbinate, Septum, Inflammation                                            1 (2%)       1 (2%)                    2 (4%)      
      Turbinate, Respiratory Epithelium,                                                                                            
        Hyperplasia                                                              1 (2%)       1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                (53)         (54)         (53)         (52)         (53)         (53)         
      Degeneration                                     1 (2%)                                                                       
      Hemorrhage                                       1 (2%)                                                                       
      Anterior Chamber, Inflammation, Suppurative                                                                       1 (2%)      
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page    9                                                              
                                                                                                                                   
NTP Experiment-Test: 96007-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                             TOXIC EQUIVALENCY FACTOR EVALUATION (TCDD)                        Date: 09/30/03    
Route: GAVAGE                                                                                                     Time: 08:37:05    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         SPRAGUE-DAWLEY RATS FEMALE                0 NG/KG      3 NG/KG      10 NG/KG     22 NG/KG     46 NG/KG     100             
                                                                                                                    NG/KG           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
SPECIAL SENSES SYSTEM - CONT                                                                                                        
      Cornea, Inflammation, Suppurative                                          1 (2%)                                 1 (2%)      
      Lens, Degeneration                                                                                   1 (2%)                   
      Retina, Atrophy                                  5 (9%)       5 (9%)       5 (9%)       3 (6%)       4 (8%)       6 (11%)     
      Retina, Degeneration                                                                                 1 (2%)                   
   Harderian Gland                                    (53)         (54)         (53)         (52)         (53)         (53)         
      Atrophy, Focal                                   1 (2%)                                                                       
      Inflammation                                    12 (23%)      3 (6%)       2 (4%)       2 (4%)       8 (15%)      6 (11%)     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (53)         (54)         (53)         (53)         (53)         (53)         
      Calculus Gross Observation                                                                                        1 (2%)      
      Calculus Micro Observation Only                  1 (2%)       1 (2%)       1 (2%)       3 (6%)       2 (4%)                   
      Casts Protein                                    3 (6%)       5 (9%)       2 (4%)                    1 (2%)       1 (2%)      
      Cyst                                             2 (4%)                                              1 (2%)       1 (2%)      
      Fibrosis                                                      1 (2%)                                                          
      Infarct                                                                    1 (2%)                                             
      Inflammation, Chronic Active                     5 (9%)       1 (2%)                    1 (2%)       1 (2%)                   
      Inflammation, Suppurative                                                  2 (4%)       1 (2%)       1 (2%)       2 (4%)      
      Mineralization                                  40 (75%)     39 (72%)     30 (57%)     32 (60%)     42 (79%)     42 (79%)     
      Necrosis                                                                                1 (2%)       1 (2%)                   
      Nephropathy                                     34 (64%)     26 (48%)     32 (60%)     36 (68%)     39 (74%)     52 (98%)     
      Papilla, Necrosis                                                          1 (2%)                                             
      Pelvis, Dilatation                               2 (4%)       1 (2%)       1 (2%)                    2 (4%)                   
      Pelvis, Inflammation                             2 (4%)       1 (2%)       1 (2%)       1 (2%)       4 (8%)       2 (4%)      
      Renal Tubule, Degeneration                                                                                        1 (2%)      
      Transitional Epithelium, Hyperplasia             3 (6%)       6 (11%)      8 (15%)      8 (15%)     11 (21%)     11 (21%)     
   Ureter                                             (1)                                                                           
      Inflammation                                     1 (100%)                                                                     
      Transitional Epithelium, Hyperplasia             1 (100%)                                                                     
   Urinary Bladder                                    (52)         (53)         (53)         (52)         (53)         (53)         
      Calculus Micro Observation Only                               1 (2%)                                                          
      Hemorrhage                                                    1 (2%)                                                          
      Inflammation                                     6 (12%)     10 (19%)      4 (8%)                    8 (15%)      3 (6%)      
      Metaplasia, Squamous                                                                                              1 (2%)      
      Transitional Epithelium, Hyperplasia             1 (2%)       2 (4%)       1 (2%)                    6 (11%)      2 (4%)      
                                                                                                                                    
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page   10                                                              
                                                                                                                                   
NTP Experiment-Test: 96007-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                             TOXIC EQUIVALENCY FACTOR EVALUATION (TCDD)                        Date: 09/30/03    
Route: GAVAGE                                                                                                     Time: 08:37:05    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         SPRAGUE-DAWLEY RATS FEMALE                100 NG/                                                                          
                                                   KG/STOP                                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
DISPOSITION SUMMARY                                                                                                                 
                                                                                                                                    
  Animals Initially In Study                          50                                                                            
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                16                                                                            
    Natural Death                                     13                                                                            
  Survivors                                                                                                                         
    Terminal Sacrifice                                21                                                                            
                                                                                                                                    
  Animals Examined Microscopically                    50                                                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Intestine Large, Colon                             (49)                                                                          
      Parasite Metazoan                                1 (2%)                                                                       
   Intestine Large, Rectum                            (50)                                                                          
      Parasite Metazoan                                5 (10%)                                                                      
   Intestine Small, Jejunum                           (50)                                                                          
      Inflammation, Chronic                            1 (2%)                                                                       
   Liver                                              (50)                                                                          
      Angiectasis                                      4 (8%)                                                                       
      Atypia Cellular                                  1 (2%)                                                                       
      Basophilic Focus                                 7 (14%)                                                                      
      Basophilic Focus, Multiple                       9 (18%)                                                                      
      Cholangiofibrosis                                1 (2%)                                                                       
      Clear Cell Focus                                 6 (12%)                                                                      
      Clear Cell Focus, Multiple                       2 (4%)                                                                       
      Cytoplasmic Alteration                           1 (2%)                                                                       
      Eosinophilic Focus                               6 (12%)                                                                      
      Eosinophilic Focus, Multiple                    21 (42%)                                                                      
      Fatty Change, Diffuse                           10 (20%)                                                                      
      Fatty Change, Focal                              8 (16%)                                                                      
      Hematopoietic Cell Proliferation                 2 (4%)                                                                       
      Hepatodiaphragmatic Nodule                       1 (2%)                                                                       
      Inflammation                                    43 (86%)                                                                      
      Mixed Cell Focus                                 1 (2%)                                                                       
      Mixed Cell Focus, Multiple                      28 (56%)                                                                      
      Necrosis                                         8 (16%)                                                                      
      Pigmentation                                    45 (90%)                                                                      
      Toxic Hepatopathy                               16 (32%)                                                                      
      Vacuolization Cytoplasmic                        1 (2%)                                                                       
      Bile Duct, Cyst                                  6 (12%)                                                                      
      Bile Duct, Fibrosis                              5 (10%)                                                                      
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page   11                                                              
                                                                                                                                   
NTP Experiment-Test: 96007-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                             TOXIC EQUIVALENCY FACTOR EVALUATION (TCDD)                        Date: 09/30/03    
Route: GAVAGE                                                                                                     Time: 08:37:05    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         SPRAGUE-DAWLEY RATS FEMALE                100 NG/                                                                          
                                                   KG/STOP                                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Bile Duct, Hyperplasia                           7 (14%)                                                                      
      Hepatocyte, Hypertrophy                         22 (44%)                                                                      
      Hepatocyte, Multinucleated                      32 (64%)                                                                      
      Oval Cell, Hyperplasia                           1 (2%)                                                                       
      Portal, Fibrosis                                 1 (2%)                                                                       
      Serosa, Inflammation, Chronic Active             1 (2%)                                                                       
   Mesentery                                          (1)                                                                           
      Artery, Inflammation, Chronic Active             1 (100%)                                                                     
   Oral Mucosa                                        (11)                                                                          
      Gingival, Hyperplasia, Squamous                  8 (73%)                                                                      
   Pancreas                                           (49)                                                                          
      Angiectasis                                      1 (2%)                                                                       
      Basophilic Focus                                 1 (2%)                                                                       
      Inflammation, Chronic Active                     4 (8%)                                                                       
      Acinus, Atrophy                                  4 (8%)                                                                       
      Artery, Inflammation, Chronic Active             2 (4%)                                                                       
   Salivary Glands                                    (49)                                                                          
      Atrophy                                          2 (4%)                                                                       
      Fibrosis                                         1 (2%)                                                                       
      Inflammation                                     1 (2%)                                                                       
   Stomach, Forestomach                               (50)                                                                          
      Hyperkeratosis                                   1 (2%)                                                                       
      Hyperplasia, Squamous                            5 (10%)                                                                      
      Inflammation                                     4 (8%)                                                                       
      Ulcer                                            4 (8%)                                                                       
   Stomach, Glandular                                 (50)                                                                          
      Erosion                                          1 (2%)                                                                       
   Tongue                                             (1)                                                                           
      Inflammation, Chronic Active                     1 (100%)                                                                     
   Tooth                                              (12)                                                                          
      Peridontal Tissue, Inflammation                 12 (100%)                                                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Heart                                              (50)                                                                          
      Cardiomyopathy                                  22 (44%)                                                                      
      Inflammation                                     1 (2%)                                                                       
      Atrium, Thrombosis                               2 (4%)                                                                       
      Epicardium, Inflammation, Chronic Active         1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                                                                                                    
                                                             Page   12                                                              
                                                                                                                                   
NTP Experiment-Test: 96007-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                             TOXIC EQUIVALENCY FACTOR EVALUATION (TCDD)                        Date: 09/30/03    
Route: GAVAGE                                                                                                     Time: 08:37:05    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         SPRAGUE-DAWLEY RATS FEMALE                100 NG/                                                                          
                                                   KG/STOP                                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (50)                                                                          
      Angiectasis                                     15 (30%)                                                                      
      Atrophy                                          4 (8%)                                                                       
      Degeneration, Cystic                            17 (34%)                                                                      
      Hyperplasia                                     20 (40%)                                                                      
      Hypertrophy                                     46 (92%)                                                                      
      Necrosis                                         3 (6%)                                                                       
      Vacuolization Cytoplasmic                       13 (26%)                                                                      
   Adrenal Medulla                                    (50)                                                                          
      Hyperplasia                                     15 (30%)                                                                      
   Islets, Pancreatic                                 (49)                                                                          
      Hyperplasia                                      1 (2%)                                                                       
   Pituitary Gland                                    (50)                                                                          
      Angiectasis                                     15 (30%)                                                                      
      Cytoplasmic Alteration                           1 (2%)                                                                       
      Vacuolization Cytoplasmic                        3 (6%)                                                                       
      Pars Distalis, Hyperplasia                      18 (36%)                                                                      
   Thyroid Gland                                      (49)                                                                          
      Angiectasis                                      1 (2%)                                                                       
      C-Cell, Hyperplasia                             15 (31%)                                                                      
      Follicular Cell, Hypertrophy                     6 (12%)                                                                      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Clitoral Gland                                     (49)                                                                          
      Atrophy                                          1 (2%)                                                                       
      Hyperplasia, Basal Cell                          1 (2%)                                                                       
      Hyperplasia, Squamous                            1 (2%)                                                                       
      Inflammation                                    35 (71%)                                                                      
      Duct, Cyst                                      35 (71%)                                                                      
   Ovary                                              (49)                                                                          
      Atrophy                                         45 (92%)                                                                      
      Cyst                                            16 (33%)                                                                      
      Inflammation, Granulomatous                      1 (2%)                                                                       
   Oviduct                                            (2)                                                                           
      Inflammation                                     2 (100%)                                                                     
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page   13                                                              
                                                                                                                                   
NTP Experiment-Test: 96007-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                             TOXIC EQUIVALENCY FACTOR EVALUATION (TCDD)                        Date: 09/30/03    
Route: GAVAGE                                                                                                     Time: 08:37:05    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         SPRAGUE-DAWLEY RATS FEMALE                100 NG/                                                                          
                                                   KG/STOP                                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
GENITAL SYSTEM - CONT                                                                                                               
   Uterus                                             (50)                                                                          
      Inflammation, Chronic Active                     1 (2%)                                                                       
      Inflammation, Suppurative                        9 (18%)                                                                      
      Metaplasia, Squamous                            33 (66%)                                                                      
      Cervix, Inflammation, Chronic Active             1 (2%)                                                                       
      Endometrium, Hyperplasia, Cystic                32 (64%)                                                                      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (50)                                                                          
      Atrophy                                          1 (2%)                                                                       
      Hyperplasia                                     36 (72%)                                                                      
      Myelofibrosis                                    1 (2%)                                                                       
   Lymph Node                                         (5)                                                                           
      Lumbar, Ectasia                                  2 (40%)                                                                      
      Lumbar, Hyperplasia, Plasma Cell                 2 (40%)                                                                      
      Mediastinal, Hemorrhage                          1 (20%)                                                                      
      Mediastinal, Hyperplasia, Plasma Cell            1 (20%)                                                                      
   Lymph Node, Mandibular                             (49)                                                                          
      Ectasia                                          2 (4%)                                                                       
      Hyperplasia, Lymphoid                            2 (4%)                                                                       
      Hyperplasia, Plasma Cell                        30 (61%)                                                                      
   Lymph Node, Mesenteric                             (49)                                                                          
      Hyperplasia, Histiocytic                         1 (2%)                                                                       
   Spleen                                             (49)                                                                          
      Hematopoietic Cell Proliferation                42 (86%)                                                                      
      Hyperplasia, Lymphoid                            1 (2%)                                                                       
      Pigmentation                                    42 (86%)                                                                      
      Lymphoid Follicle, Atrophy                       1 (2%)                                                                       
      Red Pulp, Atrophy                                1 (2%)                                                                       
   Thymus                                             (49)                                                                          
      Atrophy                                         45 (92%)                                                                      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (50)                                                                          
      Cyst                                             4 (8%)                                                                       
      Hyperplasia                                     19 (38%)                                                                      
   Skin                                               (50)                                                                          
      Ulcer                                            1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page   14                                                              
                                                                                                                                   
NTP Experiment-Test: 96007-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                             TOXIC EQUIVALENCY FACTOR EVALUATION (TCDD)                        Date: 09/30/03    
Route: GAVAGE                                                                                                     Time: 08:37:05    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         SPRAGUE-DAWLEY RATS FEMALE                100 NG/                                                                          
                                                   KG/STOP                                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (50)                                                                          
      Hemorrhage                                       1 (2%)                                                                       
      Inflammation, Suppurative                        1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Lung                                               (50)                                                                          
      Infiltration Cellular, Histiocyte               41 (82%)                                                                      
      Inflammation, Suppurative                        1 (2%)                                                                       
      Metaplasia, Squamous                             3 (6%)                                                                       
      Alveolar Epithelium, Metaplasia, Bronchiolar    31 (62%)                                                                      
      Serosa, Inflammation, Suppurative                1 (2%)                                                                       
   Nose                                               (50)                                                                          
      Inflammation                                     1 (2%)                                                                       
      Goblet Cell, Respiratory Epithelium,                                                                                          
        Hyperplasia                                    1 (2%)                                                                       
      Nasolacrimal Duct, Inflammation                  1 (2%)                                                                       
      Olfactory Epithelium, Degeneration               1 (2%)                                                                       
      Olfactory Epithelium, Inflammation               1 (2%)                                                                       
      Olfactory Epithelium, Glands, Hyperplasia        1 (2%)                                                                       
      Respiratory Epithelium, Cyst                     1 (2%)                                                                       
      Respiratory Epithelium, Inflammation,                                                                                         
        Suppurative                                    1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                (50)                                                                          
      Retinal Detachment                               1 (2%)                                                                       
      Bilateral, Cataract                              1 (2%)                                                                       
      Retina, Atrophy                                  6 (12%)                                                                      
      Retina, Degeneration                             1 (2%)                                                                       
   Harderian Gland                                    (50)                                                                          
      Hemorrhage                                       1 (2%)                                                                       
      Inflammation                                     9 (18%)                                                                      
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                             Page   15                                                              
                                                                                                                                   
NTP Experiment-Test: 96007-03         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03  
Study Type: CHRONIC                             TOXIC EQUIVALENCY FACTOR EVALUATION (TCDD)                        Date: 09/30/03    
Route: GAVAGE                                                                                                     Time: 08:37:05    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         SPRAGUE-DAWLEY RATS FEMALE                100 NG/                                                                          
                                                   KG/STOP                                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (50)                                                                          
      Accumulation, Hyaline Droplet                    2 (4%)                                                                       
      Casts Protein                                    1 (2%)                                                                       
      Mineralization                                  42 (84%)                                                                      
      Nephropathy                                     41 (82%)                                                                      
      Papilla, Transitional Epithelium, Hyperplasia    1 (2%)                                                                       
      Pelvis, Dilatation                               1 (2%)                                                                       
      Transitional Epithelium, Hyperplasia             5 (10%)                                                                      
   Urinary Bladder                                    (50)                                                                          
      Inflammation                                     2 (4%)                                                                       
                                                                                                                                    
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page   16                                                              
                                                                                                                                   
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NTP is located at the National Institute of Environmental Health Sciences, part of the National Institutes of Health.