Skip to Main Navigation
Skip to Page Content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Share This:
https://ntp.niehs.nih.gov/go/2665

TDMS Study 05052-01 Pathology Tables


                                     INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)
                                                         2,4-DICHLOROPHENOL


NTP Experiment-Test: 05052-01                                                                                     Report: PEIRPT03
Study Type: CHRONIC                                                                                               Date: 09/07/94
Route: DOSED FEED                                                                                                 Time: 20:09:14




       Facility:  Battelle Columbus Laboratory

       Chemical CAS #:  120-83-2

       Lock Date:  None

       Cage Range:  All

       Reasons For Removal:    All

       Removal Date Range:     All

       Treatment Groups:       Include All
































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

                                                             Page   1

NTP Experiment-Test: 05052-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                         2,4-DICHLOROPHENOL                                    Date: 09/07/94  
Route: DOSED FEED                                                                                                 Time: 20:09:14  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS FEMALE                   0 PPM        2500 PPM     5000 PPM                                               
                                                                                                                                    
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially In Study                          50           50           50                                                  
  Early Deaths                                                                                                                      
    Moribund                                          14            3            8                                                  
    Dead                                               2            4            2                                                  
  Survivors                                                                                                                         
    Terminal Sacrifice                                34           43           40                                                  
  Animals Examined Microscopically                    50           50           50                                                  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Intestine Large                                    (48)                      (49)                                                
      Colon, Parasite Metazoan, Single                                           1 (2%)                                             
      Rectum, Parasite Metazoan                        2 (4%)                                                                       
      Rectum, Parasite Metazoan, Multifocal            1 (2%)                                                                       
      Rectum, Parasite Metazoan, Single                                          2 (4%)                                             
   Intestine Small                                    (48)                      (49)                                                
      Ileum, Peyer's Patch, Hyperplasia, Lymphoid,                                                                                  
           Multifocal                                                            1 (2%)                                             
   Liver                                              (50)         (23)         (50)                                                
      Angiectasis, Focal                               1 (2%)                                                                       
      Angiectasis, Multifocal                                       1 (4%)       1 (2%)                                             
      Basophilic Focus, Multiple                      33 (66%)     14 (61%)     42 (84%)                                            
      Basophilic Focus, Single                         2 (4%)       2 (9%)       1 (2%)                                             
      Clear Cell Focus                                              2 (9%)                                                          
      Clear Cell Focus, Multiple                                                 1 (2%)                                             
      Clear Cell Focus, Single                         2 (4%)                    3 (6%)                                             
      Cyst                                                          1 (4%)                                                          
      Hemorrhage, Acute, Multifocal                    1 (2%)                                                                       
      Hyperplasia, Focal                                                         1 (2%)                                             
      Inflammation, Focal, Granulomatous                            2 (9%)                                                          
      Inflammation, Focal, Membranoproliferative                                 1 (2%)                                             
      Inflammation, Granulomatous, Multifocal         26 (52%)      7 (30%)     22 (44%)                                            
      Inflammation, Multifocal, Subacute                            2 (9%)                                                          
      Bile Duct, Hyperplasia, Multifocal               8 (16%)      2 (9%)       7 (14%)                                            
      Centrilobular, Pigmentation, Hemosiderin,                                                                                     
           Multifocal                                                            1 (2%)                                             
      Hepatocyte, Degeneration, Cystic, Focal          1 (2%)       3 (13%)                                                         
      Hepatocyte, Necrosis, Acute, Multifocal          3 (6%)                    1 (2%)                                             
      Hepatocyte, Necrosis, Multifocal                                           2 (4%)                                             
      Hepatocyte, Vacuolization Cytoplasmic,                                                                                        
          Multifocal                                   9 (18%)                   6 (12%)                                            
      Hepatocyte, Centrilobular, Necrosis,                                                                                          
          Multifocal, Subacute                                                   1 (2%)                                             
      Left Lateral Lobe, Angiectasis, Focal                                      1 (2%)                                             
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    2                                                              
NTP Experiment-Test: 05052-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                         2,4-DICHLOROPHENOL                                    Date: 09/07/94  
Route: DOSED FEED                                                                                                 Time: 20:09:14  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS FEMALE                   0 PPM        2500 PPM     5000 PPM                                               
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Median Lobe, Atrophy, Chronic, Multifocal                                  1 (2%)                                             
      Periportal, Hematopoietic Cell Proliferation,                                                                                 
           Multifocal                                  2 (4%)                                                                       
      Periportal, Infiltration Cellular, Acute,                                                                                     
           Multifocal, Lymphocyte                                                1 (2%)                                             
      Sinusoid, Subserosa, Congestion, Acute,                                                                                       
          Multifocal                                                             1 (2%)                                             
   Mesentery                                          (2)                       (2)                                                 
      Inflammation, Chronic, Multifocal                1 (50%)                                                                      
      Inflammation, Focal, Granulomatous               1 (50%)                                                                      
      Inflammation, Granulomatous, Multifocal                                    1 (50%)                                            
   Pancreas                                           (50)         (48)         (49)                                                
      Infiltration Cellular, Multifocal, Lymphocyte                              1 (2%)                                             
      Acinus, Atrophy, Focal                           5 (10%)     10 (21%)      2 (4%)                                             
      Acinus, Atrophy, Multifocal                     15 (30%)      8 (17%)      6 (12%)                                            
   Stomach                                            (49)                      (50)                                                
      Forestomach, Hyperkeratosis, Multifocal                                    1 (2%)                                             
      Forestomach, Hyperplasia, Multifocal,                                                                                         
          Squamous                                                               1 (2%)                                             
      Glandular, Ulcer, Acute, Multifocal              1 (2%)                                                                       
   Tooth                                                                        (1)                                                 
      Peridontal Tissue, Inflammation, Chronic                                                                                      
          Active, Multifocal                                                     1 (100%)                                           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Heart                                              (50)                      (50)                                                
      Atrium Left, Thrombosis, Multifocal, Subacute                              1 (2%)                                             
      Myocardium, Degeneration, Chronic, Multifocal   40 (80%)                  38 (76%)                                            
      Myocardium, Inflammation, Acute, Multifocal      1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Gland                                      (50)         (49)         (49)                                                
      Bilateral, Cortex, Atrophy, Diffuse                           1 (2%)                                                          
      Bilateral, Cortex, Congestion, Multifocal        1 (2%)       1 (2%)                                                          
      Bilateral, Cortex, Congestion, Multifocal,                                                                                    
           Subacute                                    1 (2%)                                                                       
      Bilateral, Cortex, Degeneration, Diffuse,                                                                                     
           Fatty                                                    1 (2%)                                                          
      Bilateral, Cortex, Degeneration, Fatty,                                                                                       
          Multifocal                                                3 (6%)       1 (2%)                                             
      Bilateral, Cortex, Hyperplasia, Focal            1 (2%)                                                                       
      Bilateral, Cortex, Hyperplasia, Multifocal       1 (2%)       7 (14%)      2 (4%)                                             
      Bilateral, Medulla, Hyperplasia, Multifocal      1 (2%)                    2 (4%)                                             
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    3                                                              
NTP Experiment-Test: 05052-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                         2,4-DICHLOROPHENOL                                    Date: 09/07/94  
Route: DOSED FEED                                                                                                 Time: 20:09:14  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS FEMALE                   0 PPM        2500 PPM     5000 PPM                                               
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ENDOCRINE SYSTEM - CONT                                                                                                             
      Bilateral, Medulla, Infiltration Cellular,                                                                                    
           Acute, Multifocal, Lymphocyte                                         1 (2%)                                             
      Capsule, Hyperplasia, Focal                                   1 (2%)                                                          
      Cortex, Cyst                                     1 (2%)                                                                       
      Cortex, Cytoplasmic Alteration, Focal            3 (6%)       3 (6%)       1 (2%)                                             
      Cortex, Cytoplasmic Alteration, Multifocal                    1 (2%)                                                          
      Cortex, Degeneration, Cystic, Focal              1 (2%)       1 (2%)                                                          
      Cortex, Degeneration, Fatty, Focal              12 (24%)      7 (14%)      6 (12%)                                            
      Cortex, Degeneration, Fatty, Multifocal          2 (4%)       1 (2%)       3 (6%)                                             
      Cortex, Hyperplasia, Focal                       8 (16%)      6 (12%)     11 (22%)                                            
      Cortex, Hyperplasia, Multifocal                  2 (4%)       3 (6%)       2 (4%)                                             
      Cortex, Hypertrophy, Focal                       2 (4%)                    1 (2%)                                             
      Cortex, Karyomegaly, Focal                       3 (6%)       2 (4%)                                                          
      Cortex, Necrosis, Multifocal                     1 (2%)                                                                       
      Cortex, Right, Atrophy, Multifocal                            1 (2%)                                                          
      Medulla, Cyst                                                 1 (2%)                                                          
      Medulla, Hyperplasia, Focal                      2 (4%)                    2 (4%)                                             
      Medulla, Hyperplasia, Multifocal                 1 (2%)                    5 (10%)                                            
      Medulla, Karyomegaly, Focal                                   1 (2%)                                                          
   Parathyroid Gland                                  (36)                      (39)                                                
      Hyperplasia, Glandular, Multifocal                                         1 (3%)                                             
      Hyperplasia, Multifocal                          1 (3%)                                                                       
   Pituitary Gland                                    (50)         (32)         (48)                                                
      Cyst, Multiple                                                1 (3%)                                                          
      Pars Distalis, Cyst                              1 (2%)       3 (9%)       2 (4%)                                             
      Pars Distalis, Cyst, Multiple                   12 (24%)      7 (22%)      6 (13%)                                            
      Pars Distalis, Cyst, Single                      1 (2%)                    1 (2%)                                             
      Pars Distalis, Hemorrhage, Focal                 1 (2%)       1 (3%)                                                          
      Pars Distalis, Hemorrhage, Multifocal            4 (8%)                    4 (8%)                                             
      Pars Distalis, Hemorrhage, Multifocal,                                                                                        
          Subacute                                                               2 (4%)                                             
      Pars Distalis, Hyperplasia, Diffuse                                        1 (2%)                                             
      Pars Distalis, Hyperplasia, Focal                5 (10%)      1 (3%)       2 (4%)                                             
      Pars Distalis, Hyperplasia, Multifocal           2 (4%)                    4 (8%)                                             
      Pars Distalis, Necrosis, Chronic, Multifocal                  1 (3%)                                                          
   Thyroid Gland                                      (50)                      (49)                                                
      C-Cell, Hyperplasia, Focal                                                 1 (2%)                                             
      C-Cell, Hyperplasia, Multifocal                 30 (60%)                  25 (51%)                                            
      Follicle, Cyst, Single                           2 (4%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    4                                                              
NTP Experiment-Test: 05052-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                         2,4-DICHLOROPHENOL                                    Date: 09/07/94  
Route: DOSED FEED                                                                                                 Time: 20:09:14  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS FEMALE                   0 PPM        2500 PPM     5000 PPM                                               
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Clitoral Gland                                     (38)         (2)          (40)                                                
      Cyst                                                                       1 (3%)                                             
      Cyst, Multiple                                   2 (5%)                                                                       
      Hyperplasia, Focal, Glandular                                              3 (8%)                                             
      Inflammation, Chronic Active, Focal              1 (3%)                    1 (3%)                                             
      Inflammation, Chronic Active, Multifocal         1 (3%)                                                                       
      Inflammation, Multifocal, Subacute               1 (3%)                                                                       
      Inflammation, Multifocal, Suppurative                                      1 (3%)                                             
      Necrosis, Acute, Focal                           1 (3%)                                                                       
      Necrosis, Chronic Active, Focal                  1 (3%)                                                                       
   Ovary                                              (50)         (5)          (49)                                                
      Necrosis, Coagulative, Multifocal                             1 (20%)                                                         
      Bilateral, Periovarian Tissue, Cyst              1 (2%)                                                                       
      Bilateral, Follicle, Cyst                        1 (2%)                                                                       
      Follicle, Cyst                                                             2 (4%)                                             
      Follicle, Cyst, Multiple                         1 (2%)                    5 (10%)                                            
      Follicle, Cyst, Single                           2 (4%)                                                                       
      Germinal Epithelium, Mineralization,                                                                                          
          Multifocal                                   1 (2%)                                                                       
      Left, Follicle, Cyst                             1 (2%)                                                                       
      Periovarian Tissue, Cyst                         1 (2%)       1 (20%)      3 (6%)                                             
      Periovarian Tissue, Right, Cyst                  1 (2%)       1 (20%)                                                         
      Periovarian Tissue, Left, Cyst                                2 (40%)      1 (2%)                                             
   Uterus                                             (50)         (10)         (50)                                                
      Abscess                                          2 (4%)                                                                       
      Inflammation, Chronic Active, Multifocal         1 (2%)                                                                       
      Bilateral, Lumen, Ectasia                                     1 (10%)                                                         
      Bilateral, Lumen, Ectasia, Multifocal                                      1 (2%)                                             
      Cervix, Diverticulum                             2 (4%)       1 (10%)      1 (2%)                                             
      Cervix, Fibrosis, Chronic, Multifocal                                      1 (2%)                                             
      Cervix, Inflammation, Chronic Active,                                                                                         
          Multifocal                                                1 (10%)      1 (2%)                                             
      Cervix, Inflammation, Multifocal, Suppurative    1 (2%)                                                                       
      Cervix, Prolapse, Multifocal                                  1 (10%)                                                         
      Endometrium, Hemorrhage, Multifocal                           1 (10%)                                                         
      Endometrium, Hyperplasia, Cystic, Glandular,                                                                                  
           Multifocal                                 24 (48%)                  32 (64%)                                            
      Lumen, Ectasia, Focal                                                      1 (2%)                                             
      Lumen, Ectasia, Multifocal                       3 (6%)                    5 (10%)                                            
      Lumen, Hemorrhage, Focal, Subacute                            2 (20%)                                                         
      Lumen, Right, Ectasia, Focal                     1 (2%)       1 (10%)                                                         
      Lumen, Right, Ectasia, Multifocal                1 (2%)       1 (10%)      1 (2%)                                             
      Lumen, Left, Ectasia, Focal                                                1 (2%)                                             
      Serosa, Inflammation, Chronic, Focal             1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    5                                                              
NTP Experiment-Test: 05052-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                         2,4-DICHLOROPHENOL                                    Date: 09/07/94  
Route: DOSED FEED                                                                                                 Time: 20:09:14  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS FEMALE                   0 PPM        2500 PPM     5000 PPM                                               
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Blood                                              (12)                      (8)                                                 
      Neutrophilia                                                               1 (13%)                                            
   Bone Marrow                                        (50)                      (49)                                                
      Hyperplasia, Multifocal, Neutrophil              1 (2%)                    3 (6%)                                             
      Hyperplasia, Multifocal, Reticulum Cell          5 (10%)                                                                      
      Inflammation, Granulomatous, Multifocal                                    1 (2%)                                             
      Myelofibrosis, Multifocal                                                  2 (4%)                                             
      Erythroid Cell, Hypoplasia, Multifocal                                     1 (2%)                                             
   Lymph Node                                         (48)         (47)         (50)                                                
      Hemorrhage                                       1 (2%)                                                                       
      Inflammation, Granulomatous, Multifocal                       1 (2%)                                                          
      Cortex, Mandibular, Cyst, Multiple                            1 (2%)                                                          
      Mandibular, Angiectasis, Multifocal                                        1 (2%)                                             
      Mandibular, Depletion Lymphoid, Multifocal                                 1 (2%)                                             
      Mandibular, Hemorrhage, Multifocal               9 (19%)      5 (11%)     16 (32%)                                            
      Mandibular, Hyperplasia, Histiocytic,                                                                                         
          Multifocal                                                             1 (2%)                                             
      Mandibular, Hyperplasia, Lymphoid, Multifocal    5 (10%)                   3 (6%)                                             
      Mandibular, Hyperplasia, Multifocal, Plasma                                                                                   
          Cell                                         4 (8%)       8 (17%)      2 (4%)                                             
      Mandibular, Inflammation, Chronic, Multifocal                 1 (2%)       4 (8%)                                             
      Mandibular, Inflammation, Granulomatous,                                                                                      
           Multifocal                                  4 (8%)       7 (15%)      4 (8%)                                             
      Mandibular, Pigmentation, Hemosiderin,                                                                                        
          Multifocal                                                1 (2%)       1 (2%)                                             
      Mediastinal, Depletion Lymphoid, Multifocal      1 (2%)                                                                       
      Mediastinal, Hemorrhage, Multifocal              6 (13%)                   2 (4%)                                             
      Mediastinal, Inflammation, Chronic,                                                                                           
          Multifocal                                                             1 (2%)                                             
      Mediastinal, Inflammation, Granulomatous,                                                                                     
           Multifocal                                  6 (13%)                   4 (8%)                                             
   Spleen                                             (50)         (48)         (50)                                                
      Lymphoid Follicle, Depletion Lymphoid,                                                                                        
          Multifocal                                   2 (4%)       2 (4%)       1 (2%)                                             
      Lymphoid Follicle, Inflammation,                                                                                              
          Granulomatous, Multifocal                    2 (4%)                                                                       
      Red Pulp, Congestion, Focal                      1 (2%)       1 (2%)                                                          
      Red Pulp, Fibrosis, Focal                                     1 (2%)                                                          
      Red Pulp, Hematopoietic Cell Proliferation,                                                                                   
           Multifocal                                 25 (50%)     17 (35%)     30 (60%)                                            
      Red Pulp, Hematopoietic Cell Proliferation,                                                                                   
           Multiple                                                 1 (2%)                                                          
      Red Pulp, Inflammation, Chronic Active,                                                                                       
          Multifocal                                                1 (2%)                                                          
      Red Pulp, Inflammation, Granulomatous,                                                                                        
          Multifocal                                                1 (2%)       2 (4%)                                             
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    6                                                              
NTP Experiment-Test: 05052-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                         2,4-DICHLOROPHENOL                                    Date: 09/07/94  
Route: DOSED FEED                                                                                                 Time: 20:09:14  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS FEMALE                   0 PPM        2500 PPM     5000 PPM                                               
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
HEMATOPOIETIC SYSTEM - CONT                                                                                                         
      Red Pulp, Necrosis, Acute, Focal                 1 (2%)                                                                       
      Red Pulp, Necrosis, Acute, Multifocal                                      1 (2%)                                             
      Red Pulp, Pigmentation, Hemosiderin,                                                                                          
          Multifocal                                   2 (4%)       3 (6%)       2 (4%)                                             
   Thymus                                             (39)                      (47)                                                
      Depletion Lymphoid, Multifocal                  30 (77%)                  36 (77%)                                            
      Pigmentation, Hemosiderin, Multifocal                                      1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (46)         (9)          (46)                                                
      Acinus, Hyperplasia, Cystic, Multifocal         26 (57%)                  27 (59%)                                            
      Acinus, Hyperplasia, Cystic, Multiple            1 (2%)                                                                       
   Skin                                               (50)         (2)          (50)                                                
      Abdominal, Ulcer, Acute, Focal                                             1 (2%)                                             
      Axillary, Subcutaneous Tissue, Inflammation,                                                                                  
           Chronic Active, Multifocal                  1 (2%)                                                                       
      Hindlimb, Subcutaneous Tissue, Inflammation,                                                                                  
           Chronic Active, Granulomatous                            1 (50%)                                                         
      Hindlimb, Epidermis, Acanthosis, Multifocal                   1 (50%)                                                         
      Hindlimb, Epidermis, Hyperkeratosis,                                                                                          
          Multifocal                                                1 (50%)                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (49)                      (50)                                                
      Femur, Osteopetrosis, Multifocal                 7 (14%)                  11 (22%)                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (50)                      (48)                                                
      Cerebellum, Hemorrhage, Acute, Focal             1 (2%)                                                                       
      Cerebellum, Hemorrhage, Multifocal                                         1 (2%)                                             
      Cerebrum, Compression, Focal                     9 (18%)                   7 (15%)                                            
      Cerebrum, Hemorrhage, Focal                                                1 (2%)                                             
      Cerebrum, Perivascular Cuffing, Focal                                      1 (2%)                                             
      Medulla, Hemorrhage, Focal                                                 1 (2%)                                             
      Medulla, Hemorrhage, Multifocal                  1 (2%)                                                                       
      Ventricle, Hydrocephalus, Multifocal             3 (6%)                    5 (10%)                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    7                                                              
NTP Experiment-Test: 05052-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                         2,4-DICHLOROPHENOL                                    Date: 09/07/94  
Route: DOSED FEED                                                                                                 Time: 20:09:14  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS FEMALE                   0 PPM        2500 PPM     5000 PPM                                               
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Lung                                               (50)         (1)          (50)                                                
      Congestion, Acute, Diffuse                                    1 (100%)                                                        
      Congestion, Acute, Multifocal                    2 (4%)                                                                       
      Hemorrhage, Acute, Multifocal                    2 (4%)                                                                       
      Pigmentation, Hemosiderin, Multifocal                                      1 (2%)                                             
      Alveolar Epithelium, Hyperplasia, Focal                                    2 (4%)                                             
      Alveolar Epithelium, Hyperplasia, Multifocal     1 (2%)                                                                       
      Bronchiole, Epithelium, Hyperplasia,                                                                                          
          Multifocal                                                             1 (2%)                                             
      Interstitium, Inflammation, Acute, Focal         1 (2%)                                                                       
      Interstitium, Inflammation, Acute, Multifocal                              1 (2%)                                             
      Interstitium, Inflammation, Chronic, Focal                                 1 (2%)                                             
      Interstitium, Inflammation, Multifocal,                                                                                       
          Subacute                                                               1 (2%)                                             
   Nose                                               (45)                      (45)                                                
      Nasolacrimal Duct, Inflammation, Focal,                                                                                       
          Subacute                                     5 (11%)                   7 (16%)                                            
      Nasolacrimal Duct, Inflammation, Multifocal,                                                                                  
           Subacute                                   18 (40%)                   9 (20%)                                            
      Respiratory Epithelium, Degeneration,                                                                                         
          Multifocal                                  19 (42%)                  17 (38%)                                            
      Submucosa, Respiratory Epithelium,                                                                                            
          Congestion, Acute, Multifocal                1 (2%)                                                                       
      Submucosa, Respiratory Epithelium,                                                                                            
          Inflammation, Multifocal, Subacute          21 (47%)                  24 (53%)                                            
   Trachea                                            (49)                      (48)                                                
      Wall, Hemorrhage, Multifocal                                               1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                (4)          (1)          (4)                                                 
      Hemorrhage, Acute, Multifocal                    1 (25%)                                                                      
      Lens, Cataract                                                1 (100%)     3 (75%)                                            
      Lens, Cataract, Multifocal                       1 (25%)                                                                      
      Retina, Atrophy, Multifocal                      1 (25%)      1 (100%)     3 (75%)                                            
   Harderian Gland                                    (40)                      (42)                                                
      Inflammation, Focal, Subacute                                              2 (5%)                                             
      Inflammation, Multifocal, Subacute              15 (38%)                   8 (19%)                                            
      Bilateral, Inflammation, Multifocal, Subacute    1 (3%)                    2 (5%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    8                                                              
NTP Experiment-Test: 05052-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                         2,4-DICHLOROPHENOL                                    Date: 09/07/94  
Route: DOSED FEED                                                                                                 Time: 20:09:14  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS FEMALE                   0 PPM        2500 PPM     5000 PPM                                               
                                                                                                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (50)         (1)          (49)                                                
      Bilateral, Nephropathy, Chronic, Multifocal     46 (92%)                  33 (67%)                                            
      Bilateral, Nephropathy, Multifocal                                         1 (2%)                                             
      Cortex, Casts, Single                            1 (2%)                                                                       
      Cortex, Infarct, Focal                                                     1 (2%)                                             
      Cortex, Inflammation, Chronic, Focal             1 (2%)                    1 (2%)                                             
      Cortex, Left, Cyst, Single                                    1 (100%)     1 (2%)                                             
      Medulla, Left, Cyst, Multiple                    1 (2%)                                                                       
      Renal Tubule, Degeneration, Acute, Multifocal    2 (4%)                    1 (2%)                                             
      Renal Tubule, Hyperplasia, Focal                                           1 (2%)                                             
      Renal Tubule, Vacuolization Cytoplasmic,                                                                                      
           Multifocal                                  1 (2%)                                                                       
   Urinary Bladder                                    (50)         (1)          (48)                                                
      Calculus Micro Observation Only                                            1 (2%)                                             
      Lumen, Calculus Gross Observation                             1 (100%)                                                        
      Mucosa, Hyperplasia, Chronic, Multifocal                      1 (100%)                                                        
      Mucosa, Hyperplasia, Multifocal                                            1 (2%)                                             
      Mucosa, Hyperplasia, Multifocal, Squamous                                  1 (2%)                                             
      Mucosa, Metaplasia, Multifocal, Squamous                                   1 (2%)                                             
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    9                                                              
NTP Experiment-Test: 05052-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                         2,4-DICHLOROPHENOL                                    Date: 09/07/94  
Route: DOSED FEED                                                                                                 Time: 20:09:14  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     0 PPM        5000 PPM     10000                                                  
                                                                             PPM                                                    
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially In Study                          50           50           50                                                  
  Early Deaths                                                                                                                      
    Moribund                                          12           16           12                                                  
    Dead                                               5            9            6                                                  
  Survivors                                                                                                                         
    Terminal Sacrifice                                33           25           32                                                  
  Animals Examined Microscopically                    50           50           50                                                  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Esophagus                                          (50)                      (50)                                                
      Submucosa, Inflammation, Chronic, Multifocal                               1 (2%)                                             
   Intestine Large                                    (47)         (1)          (47)                                                
      Colon, Peyer's Patch, Hyperplasia, Lymphoid,                                                                                  
           Multifocal                                                            3 (6%)                                             
      Colon, Mesothelium, Inflammation, Chronic                                                                                     
          Active, Multifocal                                        1 (100%)                                                        
      Lamina Propria, Rectum, Inflammation,                                                                                         
          Multifocal, Subacute                                      1 (100%)                                                        
      Peyer's Patch, Rectum, Hyperplasia, Lymphoid,                                                                                 
           Multifocal                                                            1 (2%)                                             
      Rectum, Parasite Metazoan                        1 (2%)                                                                       
      Rectum, Mesothelium, Inflammation, Chronic                                                                                    
          Active, Multifocal                                        1 (100%)                                                        
   Intestine Small                                    (47)         (1)          (47)                                                
      Necrosis                                                      1 (100%)                                                        
      Jejunum, Inflammation, Chronic Active,                                                                                        
          Multifocal, Proliferative                                 1 (100%)                                                        
      Jejunum, Necrosis                                             1 (100%)                                                        
      Jejunum, Lamina Propria, Metaplasia,                                                                                          
          Multifocal, Osseous                                       1 (100%)                                                        
      Jejunum, Subserosa, Diverticulum                              1 (100%)                                                        
      Mucosa, Necrosis                                              1 (100%)                                                        
   Liver                                              (50)         (50)         (50)                                                
      Angiectasis, Focal                               4 (8%)                                                                       
      Angiectasis, Multifocal                          1 (2%)                                                                       
      Basophilic Focus                                 1 (2%)                    3 (6%)                                             
      Basophilic Focus, Focal                          1 (2%)                                                                       
      Basophilic Focus, Multiple                      14 (28%)     12 (24%)     11 (22%)                                            
      Basophilic Focus, Single                         2 (4%)       2 (4%)       1 (2%)                                             
      Clear Cell Focus                                 1 (2%)                                                                       
      Clear Cell Focus, Focal                                                    1 (2%)                                             
      Clear Cell Focus, Multiple                       1 (2%)       1 (2%)       4 (8%)                                             
      Clear Cell Focus, Single                                      1 (2%)       3 (6%)                                             
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   10                                                              
NTP Experiment-Test: 05052-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                         2,4-DICHLOROPHENOL                                    Date: 09/07/94  
Route: DOSED FEED                                                                                                 Time: 20:09:14  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     0 PPM        5000 PPM     10000                                                  
                                                                             PPM                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Eosinophilic Focus                                                         2 (4%)                                             
      Eosinophilic Focus, Multiple                     3 (6%)                    3 (6%)                                             
      Eosinophilic Focus, Single                       1 (2%)       1 (2%)       1 (2%)                                             
      Hyperplasia, Focal                               1 (2%)                                                                       
      Inflammation, Granulomatous, Multifocal          5 (10%)      7 (14%)      2 (4%)                                             
      Mixed Cell Focus                                 1 (2%)                                                                       
      Bile Duct, Hyperplasia, Chronic, Multifocal      1 (2%)                                                                       
      Bile Duct, Hyperplasia, Cystic, Multifocal                                 1 (2%)                                             
      Bile Duct, Hyperplasia, Multifocal              35 (70%)     30 (60%)     23 (46%)                                            
      Bile Duct, Hyperplasia, Multifocal, Nodular      1 (2%)                                                                       
      Capsule, Hematocyst, Single                                                1 (2%)                                             
      Centrilobular, Necrosis, Acute, Multifocal                                 1 (2%)                                             
      Hepatocyte, Cytoplasmic Alteration, Focal        1 (2%)                    2 (4%)                                             
      Hepatocyte, Cytoplasmic Alteration,                                                                                           
          Multifocal                                                2 (4%)                                                          
      Hepatocyte, Degeneration, Cystic, Focal         10 (20%)      7 (14%)      6 (12%)                                            
      Hepatocyte, Degeneration, Cystic, Multifocal     9 (18%)      5 (10%)      2 (4%)                                             
      Hepatocyte, Necrosis, Acute, Multifocal                                    2 (4%)                                             
      Hepatocyte, Necrosis, Focal                                                1 (2%)                                             
      Hepatocyte, Necrosis, Multifocal                                           1 (2%)                                             
      Hepatocyte, Necrosis, Multifocal, Subacute       1 (2%)                                                                       
      Hepatocyte, Vacuolization Cytoplasmic, Focal                               1 (2%)                                             
      Hepatocyte, Vacuolization Cytoplasmic,                                                                                        
          Multifocal                                   8 (16%)      8 (16%)     10 (20%)                                            
      Left Lateral Lobe, Necrosis, Acute, Focal                     1 (2%)                                                          
      Median Lobe, Hepatocyte, Degeneration, Fatty,                                                                                 
           Multifocal                                                            1 (2%)                                             
   Mesentery                                          (3)          (2)          (2)                                                 
      Inflammation, Granulomatous, Multifocal                       1 (50%)                                                         
      Necrosis, Chronic, Focal                                                   1 (50%)                                            
      Fat, Necrosis                                                              1 (50%)                                            
      Fat, Necrosis, Acute, Multifocal                 1 (33%)                                                                      
      Fat, Necrosis, Chronic, Multifocal               1 (33%)                                                                      
   Pancreas                                           (49)                      (49)                                                
      Acinus, Atrophy, Focal                           2 (4%)                    7 (14%)                                            
      Acinus, Atrophy, Multifocal                     27 (55%)                  16 (33%)                                            
      Acinus, Cytoplasmic Alteration, Focal            2 (4%)                                                                       
      Acinus, Cytoplasmic Alteration, Multifocal                                 1 (2%)                                             
      Artery, Inflammation, Chronic Active,                                                                                         
          Multifocal                                                             1 (2%)                                             
      Duct, Ectasia, Focal                             1 (2%)                                                                       
      Duct, Ectasia, Multifocal                        1 (2%)                    1 (2%)                                             
   Salivary Glands                                    (50)                      (50)                                                
      Acinus, Atrophy, Focal                           1 (2%)                                                                       
      Acinus, Atrophy, Multifocal                      1 (2%)                                                                       
   Stomach                                            (49)         (2)          (49)                                                
      Forestomach, Acanthosis, Focal                                1 (50%)                                                         
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   11                                                              
NTP Experiment-Test: 05052-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                         2,4-DICHLOROPHENOL                                    Date: 09/07/94  
Route: DOSED FEED                                                                                                 Time: 20:09:14  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     0 PPM        5000 PPM     10000                                                  
                                                                             PPM                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Forestomach, Acanthosis, Multifocal              2 (4%)                                                                       
      Forestomach, Hyperkeratosis, Focal                            1 (50%)                                                         
      Forestomach, Hyperkeratosis, Multifocal          1 (2%)                                                                       
      Forestomach, Ulcer, Focal, Subacute              1 (2%)                                                                       
      Forestomach, Ulcer, Multifocal, Subacute         1 (2%)                                                                       
      Forestomach, Muscularis, Inflammation,                                                                                        
          Chronic, Multifocal                                                    1 (2%)                                             
      Forestomach, Muscularis, Mineralization,                                                                                      
           Multifocal                                  1 (2%)                                                                       
      Glandular, Inflammation, Chronic, Multifocal                               1 (2%)                                             
      Glandular, Necrosis, Acute, Focal                1 (2%)                                                                       
      Glandular, Necrosis, Acute, Multifocal                        2 (100%)     1 (2%)                                             
      Glandular, Ulcer, Acute, Multifocal              1 (2%)                                                                       
      Glandular, Ulcer, Focal, Subacute                1 (2%)                                                                       
      Muscularis, Glandular, Mineralization,                                                                                        
          Multifocal                                   1 (2%)                                                                       
      Submucosa, Glandular, Inflammation,                                                                                           
          Multifocal, Subacute                         1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Heart                                              (50)         (2)          (50)                                                
      Artery, Mineralization, Multifocal               1 (2%)                                                                       
      Atrium Left, Thrombosis                                                    1 (2%)                                             
      Atrium Left, Thrombosis, Chronic                              1 (50%)                                                         
      Atrium Left, Thrombosis, Multiple, Subacute                                1 (2%)                                             
      Atrium Left, Thrombosis, Single                  2 (4%)                                                                       
      Myocardium, Degeneration, Chronic, Multifocal   46 (92%)      2 (100%)    44 (88%)                                            
      Myocardium, Degeneration, Multifocal             1 (2%)                    1 (2%)                                             
      Myocardium, Inflammation, Chronic, Multifocal    1 (2%)                                                                       
      Myocardium, Mineralization, Multifocal           1 (2%)                    1 (2%)                                             
      Ventricle Left, Thrombosis, Chronic, Focal       1 (2%)                                                                       
      Ventricle Left, Thrombosis, Multiple                                       1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Gland                                      (50)         (3)          (50)                                                
      Bilateral, Cortex, Hematopoietic Cell                                                                                         
          Proliferation, Multifocal                                              1 (2%)                                             
      Bilateral, Cortex, Hyperplasia, Multifocal       3 (6%)                                                                       
      Bilateral, Cortex, Vacuolization Cytoplasmic,                                                                                 
           Multifocal                                  1 (2%)                    1 (2%)                                             
      Bilateral, Medulla, Hyperplasia, Multifocal      1 (2%)                                                                       
      Cortex, Congestion, Multifocal                                             1 (2%)                                             
      Cortex, Cytoplasmic Alteration, Focal            1 (2%)                    2 (4%)                                             
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   12                                                              
NTP Experiment-Test: 05052-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                         2,4-DICHLOROPHENOL                                    Date: 09/07/94  
Route: DOSED FEED                                                                                                 Time: 20:09:14  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     0 PPM        5000 PPM     10000                                                  
                                                                             PPM                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ENDOCRINE SYSTEM - CONT                                                                                                             
      Cortex, Degeneration, Fatty, Focal               5 (10%)      1 (33%)      6 (12%)                                            
      Cortex, Degeneration, Fatty, Multifocal          5 (10%)                   1 (2%)                                             
      Cortex, Hematopoietic Cell Proliferation,                                                                                     
           Multifocal                                  1 (2%)                                                                       
      Cortex, Hyperplasia, Focal                       6 (12%)                   5 (10%)                                            
      Cortex, Hyperplasia, Multifocal                  1 (2%)                    1 (2%)                                             
      Cortex, Karyomegaly, Focal                                                 1 (2%)                                             
      Cortex, Necrosis, Multifocal                                               1 (2%)                                             
      Cortex, Nuclear Alteration, Focal                1 (2%)                                                                       
      Cortex, Vacuolization Cytoplasmic, Diffuse       1 (2%)                                                                       
      Cortex, Vacuolization Cytoplasmic, Multifocal    4 (8%)                                                                       
      Medulla, Cyst, Single                            1 (2%)                                                                       
      Medulla, Hyperplasia, Focal                      6 (12%)                  10 (20%)                                            
      Medulla, Hyperplasia, Multifocal                 6 (12%)                   3 (6%)                                             
   Islets, Pancreatic                                 (49)                      (49)                                                
      Hyperplasia, Focal                                                         1 (2%)                                             
   Parathyroid Gland                                  (42)         (1)          (44)                                                
      Cytoplasmic Alteration, Focal                    1 (2%)                                                                       
      Hyperplasia, Diffuse                             1 (2%)                                                                       
      Hyperplasia, Focal                               1 (2%)                                                                       
      Hyperplasia, Multifocal                          2 (5%)                    2 (5%)                                             
   Pituitary Gland                                    (49)         (44)         (49)                                                
      Pars Distalis, Cyst                              1 (2%)       4 (9%)                                                          
      Pars Distalis, Cyst, Multiple                                 1 (2%)       1 (2%)                                             
      Pars Distalis, Hemorrhage, Focal                                           1 (2%)                                             
      Pars Distalis, Hyperplasia, Focal                7 (14%)      7 (16%)      5 (10%)                                            
      Pars Distalis, Hyperplasia, Multifocal                                     5 (10%)                                            
      Pars Distalis, Karyomegaly, Multifocal                        1 (2%)                                                          
      Pars Intermedia, Cyst                            2 (4%)                                                                       
      Pars Intermedia, Cyst, Multiple                  2 (4%)                                                                       
      Pars Intermedia, Hemorrhage, Chronic, Focal                   1 (2%)                                                          
   Thyroid Gland                                      (49)         (49)         (50)                                                
      Bilateral, Follicle, Cyst, Multiple                           1 (2%)                                                          
      C-Cell, Hyperplasia, Focal                       6 (12%)      4 (8%)       6 (12%)                                            
      C-Cell, Hyperplasia, Multifocal                  5 (10%)      5 (10%)      3 (6%)                                             
      Follicle, Cyst                                   1 (2%)                    5 (10%)                                            
      Follicle, Cyst, Multiple                                                   1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   13                                                              
NTP Experiment-Test: 05052-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                         2,4-DICHLOROPHENOL                                    Date: 09/07/94  
Route: DOSED FEED                                                                                                 Time: 20:09:14  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     0 PPM        5000 PPM     10000                                                  
                                                                             PPM                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Epididymis                                         (50)         (1)          (50)                                                
      Bilateral, Inflammation, Chronic, Multifocal                               1 (2%)                                             
      Bilateral, Inflammation, Multifocal, Subacute                              1 (2%)                                             
      Head, Granuloma Sperm, Single                                 1 (100%)                                                        
   Penis                                                                        (1)                                                 
      Inflammation, Acute, Multifocal, Necrotizing                               1 (100%)                                           
   Preputial Gland                                    (43)         (3)          (47)                                                
      Abscess                                          1 (2%)                                                                       
      Hyperplasia, Focal, Glandular                    1 (2%)                                                                       
      Hyperplasia, Glandular, Multifocal               1 (2%)                                                                       
      Hyperplasia, Multifocal, Nodular, Squamous                                 1 (2%)                                             
      Infiltration Cellular, Mononuclear Cell,                                                                                      
           Mononuclear Cell, Multifocal                1 (2%)                                                                       
      Inflammation, Chronic, Multifocal                1 (2%)                                                                       
      Inflammation, Chronic Active, Multifocal         4 (9%)                    3 (6%)                                             
      Inflammation, Chronic Active, Multifocal,                                                                                     
           Necrotizing                                                           1 (2%)                                             
      Inflammation, Multifocal, Subacute               2 (5%)                                                                       
      Bilateral, Hyperplasia, Glandular, Multifocal    1 (2%)                                                                       
      Bilateral, Inflammation, Chronic Active,                                                                                      
           Multifocal                                 27 (63%)                  36 (77%)                                            
      Bilateral, Duct, Ectasia, Focal                  1 (2%)                    1 (2%)                                             
      Bilateral, Duct, Ectasia, Multifocal             6 (14%)                   2 (4%)                                             
      Duct, Ectasia, Focal                                                       3 (6%)                                             
      Duct, Ectasia, Multifocal                        1 (2%)                    1 (2%)                                             
      Duct, Right, Ectasia, Diffuse                    1 (2%)                                                                       
   Prostate                                           (48)         (3)          (50)                                                
      Dilatation, Multifocal                                        1 (33%)                                                         
      Inflammation, Chronic, Multifocal                6 (13%)                   3 (6%)                                             
      Inflammation, Chronic, Multifocal,                                                                                            
          Suppurative                                  2 (4%)                                                                       
      Inflammation, Chronic Active, Multifocal                      2 (67%)      2 (4%)                                             
      Inflammation, Focal, Subacute                                              1 (2%)                                             
      Inflammation, Granulomatous, Multifocal          1 (2%)                                                                       
      Inflammation, Multifocal, Subacute               2 (4%)                    3 (6%)                                             
      Epithelium, Hyperplasia, Multifocal              1 (2%)                                                                       
      Serosa, Inflammation, Chronic, Multifocal                                  1 (2%)                                             
   Seminal Vesicle                                                 (1)                                                              
      Dilatation, Multifocal                                        1 (100%)                                                        
   Testes                                             (50)         (38)         (50)                                                
      Atrophy, Multifocal                                                        1 (2%)                                             
      Bilateral, Atrophy, Multifocal                   1 (2%)                                                                       
      Bilateral, Interstitial Cell, Hyperplasia,                                                                                    
           Multifocal                                  2 (4%)                    4 (8%)                                             
      Bilateral, Seminiferous Tubule, Atrophy,                                                                                      
           Chronic, Multifocal                                                   1 (2%)                                             
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   14                                                              
NTP Experiment-Test: 05052-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                         2,4-DICHLOROPHENOL                                    Date: 09/07/94  
Route: DOSED FEED                                                                                                 Time: 20:09:14  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     0 PPM        5000 PPM     10000                                                  
                                                                             PPM                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
GENITAL SYSTEM - CONT                                                                                                               
      Bilateral, Seminiferous Tubule, Atrophy,                                                                                      
           Multifocal                                 27 (54%)     20 (53%)     20 (40%)                                            
      Interstitial Cell, Hyperplasia, Multifocal                    4 (11%)      2 (4%)                                             
      Interstitial Cell, Right, Hyperplasia,                                                                                        
          Multifocal                                   8 (16%)      3 (8%)       3 (6%)                                             
      Interstitial Cell, Left, Hyperplasia, Focal                                1 (2%)                                             
      Interstitial Cell, Left, Hyperplasia,                                                                                         
          Multifocal                                   5 (10%)      4 (11%)      2 (4%)                                             
      Interstitial Tissue, Hemorrhage, Chronic                                                                                      
          Active, Multifocal                                        1 (3%)                                                          
      Interstitial Tissue, Right, Hemorrhage,                                                                                       
          Chronic Active, Multifocal                                1 (3%)                                                          
      Left, Atrophy, Multifocal                                     1 (3%)                                                          
      Seminiferous Tubule, Atrophy, Multifocal         4 (8%)       4 (11%)      3 (6%)                                             
      Seminiferous Tubule, Right, Atrophy,                                                                                          
          Multifocal                                   5 (10%)      4 (11%)      3 (6%)                                             
      Seminiferous Tubule, Left, Atrophy,                                                                                           
          Multifocal                                   6 (12%)      3 (8%)       4 (8%)                                             
      Vein, Ectasia, Chronic, Multifocal                            1 (3%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Blood                                              (26)                      (16)                                                
      Neutrophilia                                     2 (8%)                                                                       
   Bone Marrow                                        (49)                      (50)                                                
      Hyperplasia, Multifocal, Neutrophil              4 (8%)                    1 (2%)                                             
      Myelofibrosis, Multifocal                        1 (2%)                                                                       
      Myeloid Cell, Erythroid Cell, Hypoplasia,                                                                                     
           Diffuse                                                               1 (2%)                                             
      Myeloid Cell, Erythroid Cell, Hypoplasia,                                                                                     
           Multifocal                                  2 (4%)                                                                       
   Lymph Node                                         (50)         (9)          (50)                                                
      Depletion Lymphoid, Multifocal                                             1 (2%)                                             
      Hyperplasia, Lymphoid, Multifocal                1 (2%)                                                                       
      Inguinal, Inflammation, Granulomatous,                                                                                        
          Multifocal                                                1 (11%)                                                         
      Lumbar, Inflammation, Granulomatous,                                                                                          
          Multifocal                                                1 (11%)                                                         
      Mandibular, Cyst                                 3 (6%)                    1 (2%)                                             
      Mandibular, Depletion Lymphoid, Multifocal                                 1 (2%)                                             
      Mandibular, Hemorrhage, Multifocal               3 (6%)                    5 (10%)                                            
      Mandibular, Hyperplasia, Lymphoid, Multifocal    6 (12%)                   5 (10%)                                            
      Mandibular, Hyperplasia, Multifocal, Plasma                                                                                   
          Cell                                                                   5 (10%)                                            
      Mandibular, Infiltration Cellular,                                                                                            
          Multifocal, Plasma Cell                      1 (2%)                    1 (2%)                                             
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   15                                                              
NTP Experiment-Test: 05052-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                         2,4-DICHLOROPHENOL                                    Date: 09/07/94  
Route: DOSED FEED                                                                                                 Time: 20:09:14  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     0 PPM        5000 PPM     10000                                                  
                                                                             PPM                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
HEMATOPOIETIC SYSTEM - CONT                                                                                                         
      Mandibular, Inflammation, Chronic, Multifocal    1 (2%)                    1 (2%)                                             
      Mandibular, Inflammation, Granulomatous,                                                                                      
           Multifocal                                                            1 (2%)                                             
      Mediastinal, Hemorrhage, Multifocal              3 (6%)                    4 (8%)                                             
      Mediastinal, Hyperplasia, Lymphoid,                                                                                           
          Multifocal                                   1 (2%)                                                                       
      Mediastinal, Inflammation, Chronic,                                                                                           
          Multifocal                                                1 (11%)                                                         
      Mediastinal, Inflammation, Chronic Active,                                                                                    
           Multifocal                                               1 (11%)                                                         
      Mediastinal, Inflammation, Granulomatous,                                                                                     
           Multifocal                                  1 (2%)                    3 (6%)                                             
      Mediastinal, Inflammation, Multifocal,                                                                                        
          Subacute                                     1 (2%)                                                                       
      Mediastinal, Pigmentation, Hemosiderin,                                                                                       
          Multifocal                                                1 (11%)                                                         
      Mesenteric, Cyst                                 1 (2%)                                                                       
      Mesenteric, Cyst, Multiple                       1 (2%)                    1 (2%)                                             
      Mesenteric, Hemorrhage, Multifocal               1 (2%)       1 (11%)                                                         
      Mesenteric, Hyperplasia, Lymphoid, Multifocal    1 (2%)                                                                       
      Mesenteric, Inflammation, Chronic, Multifocal    1 (2%)                                                                       
      Mesenteric, Inflammation, Granulomatous,                                                                                      
           Multifocal                                  1 (2%)       1 (11%)                                                         
      Pancreatic, Cyst                                 1 (2%)                                                                       
      Pancreatic, Hemorrhage, Multifocal               2 (4%)                                                                       
   Spleen                                             (50)         (14)         (50)                                                
      Necrosis, Diffuse, Subacute                      1 (2%)                                                                       
      Capsule, Cyst, Multiple                                       1 (7%)                                                          
      Lymphoid Follicle, Necrosis, Acute,                                                                                           
          Multifocal                                                             1 (2%)                                             
      Red Pulp, Fibrosis, Chronic, Focal                            1 (7%)                                                          
      Red Pulp, Fibrosis, Chronic, Multifocal          1 (2%)       1 (7%)                                                          
      Red Pulp, Fibrosis, Focal                        2 (4%)       1 (7%)                                                          
      Red Pulp, Fibrosis, Multifocal                   3 (6%)       1 (7%)       1 (2%)                                             
      Red Pulp, Hematopoietic Cell Proliferation,                                                                                   
           Multifocal                                  2 (4%)                    5 (10%)                                            
      Red Pulp, Pigmentation, Hemosiderin,                                                                                          
          Multifocal                                   1 (2%)                    2 (4%)                                             
   Thymus                                             (39)         (1)          (43)                                                
      Depletion Lymphoid, Multifocal                  30 (77%)                  33 (77%)                                            
      Artery, Mediastinum, Inflammation, Chronic,                                                                                   
           Multifocal, Proliferative                   1 (3%)                                                                       
      Epithelial Cell, Hyperplasia, Multifocal                      1 (100%)                                                        
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   16                                                              
NTP Experiment-Test: 05052-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                         2,4-DICHLOROPHENOL                                    Date: 09/07/94  
Route: DOSED FEED                                                                                                 Time: 20:09:14  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     0 PPM        5000 PPM     10000                                                  
                                                                             PPM                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (25)         (4)          (22)                                                
      Acinus, Hyperplasia, Cystic, Multifocal         19 (76%)                  12 (55%)                                            
      Acinus, Hyperplasia, Multifocal                  1 (4%)                    2 (9%)                                             
   Skin                                               (49)         (12)         (50)                                                
      Abdominal, Inflammation, Chronic, Focal,                                                                                      
           Suppurative                                                           1 (2%)                                             
      Abdominal, Subcutaneous Tissue, Edema,                                                                                        
          Multifocal, Subacute                                                   1 (2%)                                             
      Inguinal, Abscess                                                          1 (2%)                                             
      Inguinal, Ulcer, Chronic Active, Focal           1 (2%)                                                                       
      Inguinal, Subcutaneous Tissue, Inflammation,                                                                                  
           Chronic Active, Multifocal                                            1 (2%)                                             
      Tail, Hyperkeratosis, Multifocal                 1 (2%)                                                                       
      Thoracic, Subcutaneous Tissue, Hemorrhage,                                                                                    
           Chronic Active, Diffuse                                  1 (8%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (49)                      (48)                                                
      Femur, Osteopetrosis, Multifocal                 3 (6%)                    1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (50)         (1)          (50)                                                
      Cerebellum, Hemorrhage, Acute, Multifocal        1 (2%)                                                                       
      Cerebellum, Cerebrum, Hemorrhage, Multifocal                  1 (100%)                                                        
      Cerebrum, Hemorrhage, Acute, Multifocal          1 (2%)                                                                       
      Cerebrum, Hemorrhage, Focal                      1 (2%)                                                                       
      Medulla, Cerebrum, Hemorrhage, Acute,                                                                                         
          Multifocal                                                             1 (2%)                                             
      Third Ventricle, Hemorrhage, Focal                                         1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Lung                                               (50)         (3)          (50)                                                
      Congestion, Acute, Diffuse                                                 1 (2%)                                             
      Inflammation, Granulomatous, Multifocal          1 (2%)                    1 (2%)                                             
      Alveolar Epithelium, Hyperplasia, Multifocal     2 (4%)                                                                       
      Bronchiole, Epithelium, Hyperplasia,                                                                                          
          Multifocal                                   1 (2%)                                                                       
      Interstitium, Inflammation, Acute, Focal                                   2 (4%)                                             
      Interstitium, Inflammation, Chronic, Focal                    1 (33%)                                                         
      Interstitium, Inflammation, Chronic,                                                                                          
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   17                                                              
NTP Experiment-Test: 05052-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                         2,4-DICHLOROPHENOL                                    Date: 09/07/94  
Route: DOSED FEED                                                                                                 Time: 20:09:14  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     0 PPM        5000 PPM     10000                                                  
                                                                             PPM                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
RESPIRATORY SYSTEM - CONT                                                                                                           
          Multifocal                                   6 (12%)                   1 (2%)                                             
      Interstitium, Inflammation, Multifocal,                                                                                       
          Subacute                                                               1 (2%)                                             
      Interstitium, Metaplasia, Focal, Osseous         1 (2%)                                                                       
      Interstitium, Mineralization, Multifocal         1 (2%)       1 (33%)                                                         
      Mediastinum, Inflammation, Granulomatous,                                                                                     
           Multifocal                                                            1 (2%)                                             
   Nose                                               (45)         (48)         (46)                                                
      Degeneration, Multifocal                                                   1 (2%)                                             
      Nasolacrimal Duct, Inflammation, Chronic,                                                                                     
           Multifocal                                  1 (2%)                                                                       
      Nasolacrimal Duct, Inflammation, Focal,                                                                                       
          Subacute                                     4 (9%)       1 (2%)       6 (13%)                                            
      Nasolacrimal Duct, Inflammation, Multifocal      1 (2%)                                                                       
      Nasolacrimal Duct, Inflammation, Multifocal,                                                                                  
           Subacute                                   20 (44%)     19 (40%)     11 (24%)                                            
      Respiratory Epithelium, Degeneration,                                                                                         
          Multifocal                                  25 (56%)     38 (79%)     42 (91%)                                            
      Respiratory Epithelium, Inflammation,                                                                                         
          Chronic, Focal                               1 (2%)                                                                       
      Respiratory Epithelium, Inflammation,                                                                                         
          Multifocal, Subacute                         2 (4%)                                                                       
      Respiratory Epithelium, Metaplasia,                                                                                           
          Multifocal, Squamous                         2 (4%)                                                                       
      Submucosa, Olfactory Epithelium,                                                                                              
          Inflammation, Multifocal, Subacute           1 (2%)                                                                       
      Submucosa, Respiratory Epithelium,                                                                                            
          Concretion, Multifocal                                    1 (2%)                                                          
      Submucosa, Respiratory Epithelium,                                                                                            
          Inflammation, Acute, Focal                                             1 (2%)                                             
      Submucosa, Respiratory Epithelium,                                                                                            
          Inflammation, Acute, Multifocal              1 (2%)       3 (6%)       1 (2%)                                             
      Submucosa, Respiratory Epithelium,                                                                                            
          Inflammation, Chronic, Multifocal            4 (9%)                                                                       
      Submucosa, Respiratory Epithelium,                                                                                            
          Inflammation, Chronic, Multifocal,                                                                                        
          Suppurative                                                            1 (2%)                                             
      Submucosa, Respiratory Epithelium,                                                                                            
          Inflammation, Focal, Subacute                             2 (4%)       1 (2%)                                             
      Submucosa, Respiratory Epithelium,                                                                                            
          Inflammation, Multifocal                     1 (2%)                                                                       
      Submucosa, Respiratory Epithelium,                                                                                            
          Inflammation, Multifocal, Subacute          19 (42%)     23 (48%)     22 (48%)                                            
      Submucosa, Respiratory Epithelium,                                                                                            
          Inflammation, Multifocal, Suppurative        2 (4%)                    1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   18                                                              
NTP Experiment-Test: 05052-01         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                         2,4-DICHLOROPHENOL                                    Date: 09/07/94  
Route: DOSED FEED                                                                                                 Time: 20:09:14  
____________________________________________________________________________________________________________________________________
         FISCHER 344 RATS MALE                     0 PPM        5000 PPM     10000                                                  
                                                                             PPM                                                    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                (4)          (4)          (2)                                                 
      Cornea, Inflammation, Multifocal, Subacute       1 (25%)                                                                      
      Lens, Cataract                                                             1 (50%)                                            
      Lens, Cataract, Multifocal                       2 (50%)      2 (50%)                                                         
      Retina, Atrophy, Multifocal                      3 (75%)      2 (50%)      1 (50%)                                            
   Harderian Gland                                    (43)                      (36)                                                
      Hyperplasia, Focal, Glandular                                              1 (3%)                                             
      Hyperplasia, Glandular, Multifocal               1 (2%)                                                                       
      Inflammation, Granulomatous, Multifocal                                    1 (3%)                                             
      Inflammation, Multifocal, Subacute                                         3 (8%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (50)         (8)          (49)                                                
      Congestion, Multifocal                                        1 (13%)                                                         
      Cyst                                                          1 (13%)                                                         
      Cyst, Multiple                                   1 (2%)                                                                       
      Polycystic Kidney                                             1 (13%)                                                         
      Bilateral, Nephropathy, Chronic, Multifocal     49 (98%)      6 (75%)     48 (98%)                                            
      Bilateral, Cortex, Cyst, Multiple                             1 (13%)                                                         
      Bilateral, Cortex, Mineralization, Multifocal                 1 (13%)                                                         
      Bilateral, Pelvis, Hydronephrosis, Multifocal                 1 (13%)                                                         
      Cortex, Cyst                                     3 (6%)       1 (13%)                                                         
      Cortex, Cyst, Multiple                           2 (4%)                                                                       
      Cortex, Cyst, Single                             4 (8%)                                                                       
      Left, Nephropathy, Chronic, Multifocal           1 (2%)                                                                       
      Papilla, Epithelium, Hyperplasia, Multifocal     1 (2%)                                                                       
      Renal Tubule, Pigmentation, Multifocal           1 (2%)                                                                       
      Right, Cyst                                                   1 (13%)                                                         
   Urinary Bladder                                    (48)         (2)          (50)                                                
      Inflammation, Acute, Hemorrhagic, Multifocal                  1 (50%)                                                         
      Mucosa, Hyperplasia, Multifocal                  1 (2%)       1 (50%)      1 (2%)                                             
      Muscularis, Inflammation, Chronic Active,                                                                                     
           Multifocal                                               1 (50%)                                                         
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   19                                                              
                             ------------------------------------------------------------                                           
                             ----------              END OF REPORT             ----------                                           
                             ------------------------------------------------------------                                           

--multipart-boundary
Content-type: text/plain
Range: bytes 132950-132950/132950


--multipart-boundary--