National Toxicology Program

National Toxicology Program
https://ntp.niehs.nih.gov/go/19294

TDMS Study 96017-06 Pathology Tables

NTP Experiment-Test: 96017-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT18
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 05/19/04
Route: DOSED WATER                            WATER DISINFECTION BYPRODUCTS (DIBROMOACETIC ACID)                  Time: 09:37:47

                                                          FINAL#1 MICE




       Facility:  Southern Research Institute

       Chemical CAS #:  631-64-1

       Lock Date:  11/15/02

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

                                                              Page   1


NTP Experiment-Test: 96017-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT18  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 05/19/04    
Route: DOSED WATER                            WATER DISINFECTION BYPRODUCTS (DIBROMOACETIC ACID)                  Time: 09:37:47    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE FEMALE                           0 MG/L       50 MG/L      500 MG/L     1000                                   
                                                                                             MG/L                                   
____________________________________________________________________________________________________________________________________
                                                                                                                                    
DISPOSITION SUMMARY                                                                                                                 
                                                                                                                                    
  Animals Initially In Study                          50           50           50           50                                     
  Early Deaths                                                                                                                      
    Natural Death                                     10           13           13           11                                     
    Moribund Sacrifice                                 2            2            5            7                                     
  Survivors                                                                                                                         
    Terminal Sacrifice                                38           35           31           32                                     
    Natural Death                                                                1                                                  
                                                                                                                                    
  Animals Examined Microscopically                    50           50           50           50                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Intestine Large, Rectum                            (49)         (49)         (48)         (49)                                   
      Ulcer                                                                      1 [4.0]                                            
   Intestine Large, Cecum                             (47)         (46)         (49)         (46)                                   
      Edema                                            2 [2.0]      1 [2.0]                   3 [2.0]                               
      Inflammation, Chronic                                         1 [3.0]                   1 [2.0]                               
      Epithelium, Hyperplasia                                                    1 [3.0]                                            
   Intestine Small, Duodenum                          (46)         (48)         (48)         (45)                                   
      Epithelium, Hyperplasia                                       1 [3.0]                                                         
   Intestine Small, Jejunum                           (46)         (47)         (49)         (43)                                   
      Hyperplasia, Lymphoid                                         2 [3.0]                   2 [3.5]                               
   Intestine Small, Ileum                             (45)         (47)         (47)         (46)                                   
      Inflammation, Chronic                                         1 [3.0]                                                         
   Liver                                              (49)         (50)         (50)         (49)                                   
      Angiectasis                                      1 [4.0]      2 [3.0]                                                         
      Basophilic Focus                                              1            3            3                                     
      Clear Cell Focus                                 3            1            8            5                                     
      Eosinophilic Focus                               7            6           10            9                                     
      Hematopoietic Cell Proliferation                 2 [2.5]      4 [2.5]      2 [3.0]      2 [2.5]                               
      Hepatodiaphragmatic Nodule                                                              2                                     
      Hyperplasia, Lymphoid                            2 [3.5]      1 [2.0]                                                         
      Infarct                                                                                 1 [3.0]                               
      Infiltration Cellular, Mixed Cell                7 [2.1]      7 [2.6]      4 [2.3]      9 [2.4]                               
      Inflammation, Chronic Active                                               1 [1.0]                                            
      Mixed Cell Focus                                 2            6            3            1                                     
      Necrosis, Focal                                  3 [1.7]      2 [3.0]      3 [2.3]      2 [3.5]                               
      Tension Lipidosis                                1            3                                                               
      Centrilobular, Necrosis                                       1 [3.0]      4 [2.8]      4 [2.3]                               
      Hepatocyte, Vacuolization Cytoplasmic            2 [3.5]      7 [3.1]      4 [3.3]      2 [3.5]                               
      Kupffer Cell, Pigmentation                       3 [2.3]                                3 [2.3]                               
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Average severity grade (1-minimal;2-mild;3-moderate;4-marked)                                                                    
                                                                                                                                    
                                                             Page    2                                                              
                                                                                                                                   
NTP Experiment-Test: 96017-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT18  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 05/19/04    
Route: DOSED WATER                            WATER DISINFECTION BYPRODUCTS (DIBROMOACETIC ACID)                  Time: 09:37:47    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE FEMALE                           0 MG/L       50 MG/L      500 MG/L     1000                                   
                                                                                             MG/L                                   
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
   Mesentery                                          (28)         (20)         (16)         (19)                                   
      Fat, Necrosis                                   22 [3.3]     18 [3.4]     11 [3.5]     13 [2.8]                               
   Pancreas                                           (49)         (49)         (49)         (47)                                   
      Atrophy                                                       1 [3.0]      1 [3.0]      3 [2.7]                               
      Cyst                                                                       1 [3.0]      3 [3.0]                               
      Inflammation, Chronic                                                                   1 [3.0]                               
      Acinus, Cytoplasmic Alteration                   1 [3.0]                                                                      
   Salivary Glands                                    (50)         (49)         (50)         (50)                                   
      Hyperplasia, Lymphoid                           15 [2.7]     13 [2.2]     16 [2.2]     10 [2.5]                               
   Stomach, Forestomach                               (49)         (50)         (50)         (49)                                   
      Erosion                                                       1 [2.0]                                                         
      Inflammation, Chronic                            1 [3.0]      2 [2.0]      2 [1.5]      1 [2.0]                               
      Ulcer                                            1 [2.0]      1 [2.0]      1 [2.0]      3 [2.3]                               
      Epithelium, Hyperplasia                          4 [1.5]      5 [2.6]                   4 [2.0]                               
   Stomach, Glandular                                 (49)         (50)         (50)         (49)                                   
      Erosion                                                       1 [3.0]                   1 [3.0]                               
      Pylorus, Epithelium, Hyperplasia, Atypical                    1 [4.0]                                                         
   Tooth                                                                        (1)                                                 
      Malformation                                                               1                                                  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Blood Vessel                                       (1)          (1)          (1)                                                 
      Hypertrophy                                                                1 [4.0]                                            
      Inflammation, Chronic Active                                               1 [4.0]                                            
   Heart                                              (50)         (49)         (50)         (50)                                   
      Cardiomyopathy                                                             1 [1.0]      1 [2.0]                               
      Inflammation, Chronic                                         1 [3.0]                   1 [3.0]                               
      Inflammation, Chronic Active                                                            1 [3.0]                               
      Mineralization                                                1 [3.0]      1 [3.0]      2 [2.5]                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (50)         (50)         (50)         (49)                                   
      Accessory Adrenal Cortical Nodule                9 [3.0]     11 [3.0]      6 [3.0]      9 [3.0]                               
      Hyperplasia, Focal                                            2 [2.5]                   1 [3.0]                               
      Hypertrophy, Focal                                            1 [2.0]                                                         
      Capsule, Hyperplasia                                          1 [3.0]                   1 [2.0]                               
   Adrenal Medulla                                    (50)         (50)         (50)         (49)                                   
      Hyperplasia                                                   2 [1.0]      1 [2.0]      1 [1.0]                               
   Islets, Pancreatic                                 (49)         (49)         (49)         (46)                                   
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Average severity grade (1-minimal;2-mild;3-moderate;4-marked)                                                                    
                                                                                                                                    
                                                             Page    3                                                              
                                                                                                                                   
NTP Experiment-Test: 96017-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT18  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 05/19/04    
Route: DOSED WATER                            WATER DISINFECTION BYPRODUCTS (DIBROMOACETIC ACID)                  Time: 09:37:47    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE FEMALE                           0 MG/L       50 MG/L      500 MG/L     1000                                   
                                                                                             MG/L                                   
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ENDOCRINE SYSTEM - CONT                                                                                                             
      Hyperplasia                                      2 [2.0]      5 [2.0]      3 [1.7]      3 [2.0]                               
   Parathyroid Gland                                  (45)         (49)         (47)         (49)                                   
      Cyst                                             2 [3.0]      1 [3.0]      1 [3.0]      3 [3.0]                               
   Pituitary Gland                                    (47)         (49)         (49)         (49)                                   
      Pars Distalis, Angiectasis                       2 [2.5]      3 [2.0]      1 [2.0]      1 [2.0]                               
      Pars Distalis, Cyst                              2 [3.0]      2 [3.0]      1 [3.0]      1 [3.0]                               
      Pars Distalis, Hyperplasia, Focal                4 [2.5]      9 [2.2]      4 [1.8]      7 [1.9]                               
      Pars Intermedia, Hyperplasia, Focal              1 [3.0]                                                                      
   Thyroid Gland                                      (50)         (50)         (50)         (50)                                   
      Degeneration, Cystic                            10 [1.7]     26 [1.9]     16 [1.8]     14 [1.9]                               
      Follicular Cell, Hyperplasia                     8 [1.1]      1 [1.0]      1 [2.0]      2 [1.5]                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Clitoral Gland                                     (50)         (48)         (48)         (49)                                   
      Cyst                                                          1 [3.0]                                                         
   Ovary                                              (49)         (47)         (47)         (49)                                   
      Angiectasis                                      5 [2.8]      3 [2.7]      9 [2.4]      7 [2.6]                               
      Cyst                                            14 [3.1]     12 [2.8]     14 [3.0]     22 [3.0]                               
      Corpus Luteum, Hyperplasia                       1 [3.0]      1 [3.0]                                                         
      Granulosa Cell, Hyperplasia                      1 [2.0]                                                                      
      Interstitial Cell, Hyperplasia                                                          1 [3.0]                               
   Uterus                                             (50)         (50)         (50)         (50)                                   
      Angiectasis                                                   4 [3.0]      1 [2.0]      2 [2.0]                               
      Hyperplasia, Cystic                             44 [3.3]     42 [3.4]     44 [3.0]     39 [3.0]                               
      Inflammation, Chronic                            1 [2.0]      1 [2.0]      1 [3.0]                                            
      Metaplasia, Squamous                             1 [3.0]                   1 [3.0]      1 [3.0]                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (50)         (50)         (50)         (50)                                   
      Hyperplasia                                     20 [2.9]     26 [2.9]     24 [2.9]     20 [3.0]                               
      Infiltration Cellular, Mast Cell                              1 [3.0]                                                         
   Lymph Node                                         (12)         (13)         (11)         (8)                                    
      Hyperplasia, Lymphoid                                         1 [2.0]                                                         
      Bronchial, Hemorrhage                                         1 [3.0]                                                         
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Average severity grade (1-minimal;2-mild;3-moderate;4-marked)                                                                    
                                                                                                                                    
                                                             Page    4                                                              
                                                                                                                                   
NTP Experiment-Test: 96017-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT18  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 05/19/04    
Route: DOSED WATER                            WATER DISINFECTION BYPRODUCTS (DIBROMOACETIC ACID)                  Time: 09:37:47    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE FEMALE                           0 MG/L       50 MG/L      500 MG/L     1000                                   
                                                                                             MG/L                                   
____________________________________________________________________________________________________________________________________
                                                                                                                                    
HEMATOPOIETIC SYSTEM - CONT                                                                                                         
      Bronchial, Hyperplasia, Lymphoid                              1 [2.0]                                                         
      Deep Cervical, Hemorrhage                                                               1 [4.0]                               
      Iliac, Hematopoietic Cell Proliferation                       1 [3.0]                                                         
      Iliac, Hemorrhage                                1 [3.0]                                1 [4.0]                               
      Iliac, Hyperplasia, Lymphoid                     1 [2.0]      1 [2.0]      1 [3.0]      2 [2.0]                               
      Iliac, Pigmentation                              1 [3.0]                                                                      
      Inguinal, Hematopoietic Cell Proliferation                    1 [3.0]                                                         
      Inguinal, Hyperplasia, Lymphoid                               2 [2.5]                                                         
      Mediastinal, Hemorrhage                          1 [2.0]                                                                      
      Mediastinal, Hyperplasia, Lymphoid               1 [2.0]      1 [2.0]      1 [2.0]      1 [3.0]                               
      Mediastinal, Pigmentation                        1 [2.0]                                                                      
      Pancreatic, Hyperplasia, Lymphoid                                          1 [2.0]                                            
      Renal, Hyperplasia, Lymphoid                     1 [2.0]                   1 [3.0]      1 [2.0]                               
   Lymph Node, Mandibular                             (48)         (49)         (47)         (50)                                   
      Atrophy                                                       1 [2.0]      1 [3.0]      1 [3.0]                               
      Hematopoietic Cell Proliferation                 1 [1.0]      1 [2.0]                   2 [2.5]                               
      Hemorrhage                                                    2 [1.5]      2 [2.0]      1 [2.0]                               
      Hyperplasia, Lymphoid                           13 [2.3]      6 [2.3]      8 [2.8]      9 [2.8]                               
      Pigmentation                                    18 [2.2]     25 [2.2]     17 [2.1]     23 [2.3]                               
   Lymph Node, Mesenteric                             (49)         (49)         (48)         (45)                                   
      Angiectasis                                                                1 [2.0]                                            
      Atrophy                                                                    2 [2.5]      1 [3.0]                               
      Ectasia                                                                    1 [4.0]                                            
      Hematopoietic Cell Proliferation                 2 [1.5]                   2 [2.0]      1 [2.0]                               
      Hemorrhage                                       1 [4.0]      1 [3.0]      1 [1.0]      5 [2.4]                               
      Hyperplasia, Lymphoid                            8 [2.3]      9 [2.4]      7 [2.4]      5 [2.2]                               
      Pigmentation                                                               1 [3.0]      1 [3.0]                               
   Spleen                                             (50)         (50)         (50)         (48)                                   
      Hematopoietic Cell Proliferation                34 [2.2]     42 [2.5]     35 [2.5]     34 [2.5]                               
      Necrosis                                         1 [4.0]                                                                      
      Pigmentation                                     5 [2.8]      5 [3.0]      1 [3.0]      2 [3.0]                               
      Lymphoid Follicle, Atrophy                                    1 [2.0]      2 [3.0]      2 [2.5]                               
      Lymphoid Follicle, Hyperplasia                   8 [2.5]     11 [2.8]     14 [2.5]     12 [2.5]                               
   Thymus                                             (44)         (47)         (47)         (48)                                   
      Atrophy                                          8 [3.0]      9 [3.0]     11 [2.8]     13 [2.8]                               
      Hemorrhage                                       1 [3.0]                                                                      
      Hyperplasia, Lymphoid                                         3 [2.7]      3 [2.0]      2 [3.0]                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (50)         (50)         (50)         (50)                                   
      Hyperplasia                                      5 [1.8]      6 [2.0]      2 [2.5]      5 [2.2]                               
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Average severity grade (1-minimal;2-mild;3-moderate;4-marked)                                                                    
                                                                                                                                    
                                                             Page    5                                                              
                                                                                                                                   
NTP Experiment-Test: 96017-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT18  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 05/19/04    
Route: DOSED WATER                            WATER DISINFECTION BYPRODUCTS (DIBROMOACETIC ACID)                  Time: 09:37:47    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE FEMALE                           0 MG/L       50 MG/L      500 MG/L     1000                                   
                                                                                             MG/L                                   
____________________________________________________________________________________________________________________________________
                                                                                                                                    
INTEGUMENTARY SYSTEM - CONT                                                                                                         
   Skin                                               (50)         (50)         (50)         (50)                                   
      Edema                                                         1 [2.0]      1 [4.0]      1 [3.0]                               
      Erosion                                                                    1 [3.0]                                            
      Ulcer                                            2 [2.0]      1 [4.0]      1 [1.0]      1 [4.0]                               
      Epidermis, Hyperplasia                           2 [3.5]      1 [3.0]      2 [1.5]      1 [4.0]                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (50)         (50)         (50)         (50)                                   
      Myelofibrosis                                    1 [2.0]      2 [2.5]      1 [2.0]      2 [2.5]                               
   Skeletal Muscle                                    (3)          (4)          (2)          (5)                                    
      Inflammation, Chronic Active                                                            1 [3.0]                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (50)         (49)         (50)         (50)                                   
      Compression                                      1 [3.0]      1 [3.0]      1 [2.0]                                            
      Hemorrhage                                                    2 [2.5]                                                         
      Necrosis                                                      1 [2.0]      1 [2.0]                                            
   Peripheral Nerve                                                (1)          (1)          (1)                                    
      Atrophy                                                                                 1 [3.0]                               
   Spinal Cord                                                     (1)          (1)          (1)                                    
      Necrosis                                                      1 [3.0]                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Lung                                               (50)         (50)         (50)         (50)                                   
      Congestion                                                                 2 [3.0]                                            
      Hemorrhage                                                    2 [2.5]      2 [2.0]      3 [2.0]                               
      Hyperplasia, Lymphoid                            5 [2.0]      5 [2.2]      1 [2.0]      3 [2.3]                               
      Infiltration Cellular, Histiocyte                1 [3.0]      2 [2.0]      2 [3.5]      4 [1.8]                               
      Alveolar Epithelium, Hyperplasia                 3 [1.7]      3 [2.0]                   4 [2.0]                               
      Perivascular, Inflammation, Chronic Active                                              1 [3.0]                               
   Nose                                               (50)         (50)         (50)         (50)                                   
      Inflammation, Chronic                                                                   1 [2.0]                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                (50)         (50)         (50)         (50)                                   
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Average severity grade (1-minimal;2-mild;3-moderate;4-marked)                                                                    
                                                                                                                                    
                                                             Page    6                                                              
                                                                                                                                   
NTP Experiment-Test: 96017-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT18  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 05/19/04    
Route: DOSED WATER                            WATER DISINFECTION BYPRODUCTS (DIBROMOACETIC ACID)                  Time: 09:37:47    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE FEMALE                           0 MG/L       50 MG/L      500 MG/L     1000                                   
                                                                                             MG/L                                   
____________________________________________________________________________________________________________________________________
                                                                                                                                    
SPECIAL SENSES SYSTEM - CONT                                                                                                        
      Atrophy                                                                    1 [4.0]                                            
      Cataract                                                                   2 [1.5]      2 [1.5]                               
      Inflammation, Chronic                            2 [1.5]      2 [2.5]      3 [2.3]      3 [1.3]                               
      Cornea, Hyperplasia                              1 [2.0]                   4 [2.3]                                            
      Cornea, Mineralization                                                                  1 [2.0]                               
   Harderian Gland                                    (49)         (50)         (50)         (50)                                   
      Hyperplasia, Focal                               2 [3.0]      4 [2.8]      4 [2.0]      2 [2.0]                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (49)         (50)         (50)         (49)                                   
      Cyst                                                          1 [3.0]                   1 [3.0]                               
      Hydronephrosis                                                             1 [3.0]      1 [2.0]                               
      Hyperplasia, Lymphoid                            7 [2.3]      2 [2.5]      5 [2.2]      8 [2.4]                               
      Infarct                                          3 [1.7]      8 [1.8]      6 [1.8]      8 [2.5]                               
      Nephropathy                                     14 [1.6]      8 [1.4]     15 [1.7]     12 [1.2]                               
      Renal Tubule, Accumulation, Hyaline Droplet      1 [3.0]      1 [3.0]      2 [3.0]      2 [3.0]                               
      Renal Tubule, Dilatation                                      2 [2.5]      1 [2.0]      1 [2.0]                               
      Renal Tubule, Necrosis                                        1 [1.0]                   1 [2.0]                               
      Renal Tubule, Pigmentation                       1 [4.0]                   3 [2.3]      1 [3.0]                               
   Urinary Bladder                                    (50)         (49)         (50)         (49)                                   
      Edema                                            2 [3.0]                                                                      
      Hyperplasia, Lymphoid                            3 [3.0]      5 [2.2]      3 [2.0]      2 [2.5]                               
      Transitional Epithelium, Hyperplasia                                       1 [3.0]                                            
                                                                                                                                    
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Average severity grade (1-minimal;2-mild;3-moderate;4-marked)                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page    7                                                              
                                                                                                                                   
NTP Experiment-Test: 96017-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT18  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 05/19/04    
Route: DOSED WATER                            WATER DISINFECTION BYPRODUCTS (DIBROMOACETIC ACID)                  Time: 09:37:47    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE MALE                             0 MG/L       50 MG/L      500 MG/L     1000                                   
                                                                                             MG/L                                   
____________________________________________________________________________________________________________________________________
                                                                                                                                    
DISPOSITION SUMMARY                                                                                                                 
                                                                                                                                    
  Animals Initially In Study                          50           50           50           50                                     
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                 4            6            3            6                                     
    Natural Death                                     14            6           13           13                                     
  Survivors                                                                                                                         
    Terminal Sacrifice                                31           38           34           31                                     
  Other                                                1                                                                            
                                                                                                                                    
  Animals Examined Microscopically                    49           50           50           50                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Intestine Large, Cecum                             (43)         (49)         (48)         (46)                                   
      Edema                                            2 [2.0]      2 [2.5]      3 [2.0]      1 [2.0]                               
      Hyperplasia, Lymphoid                                                      1 [3.0]                                            
   Intestine Small, Duodenum                          (42)         (50)         (46)         (48)                                   
      Hyperplasia, Lymphoid                                         1 [2.0]                                                         
   Intestine Small, Jejunum                           (44)         (49)         (46)         (45)                                   
      Hyperplasia, Lymphoid                                                      2 [2.0]      2 [3.0]                               
   Liver                                              (49)         (50)         (50)         (50)                                   
      Angiectasis                                                                1 [3.0]                                            
      Basophilic Focus                                 2                         1            2                                     
      Clear Cell Focus                                10           13           23           13                                     
      Congestion                                       1 [3.0]                                                                      
      Cyst                                                          1 [3.0]                   1 [3.0]                               
      Eosinophilic Focus                              15           10           15           17                                     
      Hematopoietic Cell Proliferation                                                        1 [2.0]                               
      Hemorrhage                                       1 [3.0]                                                                      
      Hepatodiaphragmatic Nodule                                    1                                                               
      Infarct                                          1 [4.0]                   1 [4.0]                                            
      Infiltration Cellular, Mixed Cell                2 [2.5]      4 [2.5]      2 [2.5]      2 [2.0]                               
      Mixed Cell Focus                                 3            7            8            4                                     
      Necrosis, Focal                                  8 [2.9]      7 [2.7]      3 [2.0]      5 [2.6]                               
      Tension Lipidosis                                             1            1            2                                     
      Bile Duct, Cyst                                                            1 [1.0]                                            
      Bile Duct, Cyst Multilocular                                               1                                                  
      Centrilobular, Necrosis                          4 [3.0]      4 [2.3]                   5 [2.8]                               
      Hepatocyte, Vacuolization Cytoplasmic            8 [2.8]      9 [3.1]      4 [3.3]     10 [3.0]                               
      Kupffer Cell, Pigmentation                       1 [3.0]      1 [2.0]      1 [3.0]      1 [2.0]                               
   Mesentery                                          (7)          (7)          (10)         (7)                                    
      Inflammation, Chronic                                                      1 [3.0]                                            
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Average severity grade (1-minimal;2-mild;3-moderate;4-marked)                                                                    
                                                                                                                                    
                                                             Page    8                                                              
                                                                                                                                   
NTP Experiment-Test: 96017-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT18  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 05/19/04    
Route: DOSED WATER                            WATER DISINFECTION BYPRODUCTS (DIBROMOACETIC ACID)                  Time: 09:37:47    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE MALE                             0 MG/L       50 MG/L      500 MG/L     1000                                   
                                                                                             MG/L                                   
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Fat, Necrosis                                    5 [3.4]      6 [2.8]      7 [3.1]      4 [2.8]                               
   Pancreas                                           (46)         (50)         (50)         (49)                                   
      Necrosis                                                      1 [4.0]                                                         
      Acinus, Cytoplasmic Alteration                   2 [3.0]      2 [3.0]      2 [3.0]                                            
   Salivary Glands                                    (49)         (50)         (50)         (50)                                   
      Atrophy                                          1 [2.0]                                2 [2.0]                               
      Hyperplasia, Lymphoid                            3 [2.0]      4 [2.0]      6 [2.5]      1 [2.0]                               
   Stomach, Forestomach                               (49)         (50)         (50)         (50)                                   
      Diverticulum                                                  2            1                                                  
      Erosion                                          1 [2.0]                   1 [2.0]      2 [1.5]                               
      Inflammation, Chronic                            3 [2.0]      1 [3.0]      3 [2.3]      6 [2.5]                               
      Ulcer                                            2 [1.0]      2 [2.5]      2 [2.5]      2 [2.0]                               
      Epithelium, Hyperplasia                          4 [2.3]      3 [3.0]      4 [2.8]      7 [2.4]                               
      Epithelium, Hyperplasia, Focal                                             1 [3.0]      1 [3.0]                               
   Stomach, Glandular                                 (47)         (50)         (50)         (50)                                   
      Erosion                                          2 [3.0]      2 [2.0]      1 [3.0]                                            
      Glands, Hyperplasia                                           1 [2.0]                                                         
   Tooth                                              (5)          (6)                                                              
      Malformation                                     5            6                                                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Heart                                              (49)         (50)         (50)         (50)                                   
      Cardiomyopathy                                   1 [2.0]      1 [1.0]                                                         
      Inflammation, Chronic                            1 [2.0]                                                                      
      Mineralization                                   3 [2.3]                   2 [2.0]      1 [2.0]                               
      Myocardium, Necrosis                                          1 [3.0]                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (49)         (50)         (50)         (50)                                   
      Accessory Adrenal Cortical Nodule                7 [3.0]      5 [3.0]      4 [3.0]      6 [3.0]                               
      Hyperplasia, Focal                               4 [1.8]      7 [2.3]      5 [1.8]      1 [2.0]                               
      Hypertrophy                                      1 [3.0]                                1 [2.0]                               
      Hypertrophy, Focal                              12 [1.8]     11 [1.5]     13 [1.8]      6 [1.7]                               
      Capsule, Hyperplasia                             7 [2.3]      4 [2.8]      1 [2.0]      5 [2.4]                               
   Adrenal Medulla                                    (49)         (50)         (50)         (50)                                   
      Hyperplasia                                      1 [2.0]      1 [1.0]                   1 [1.0]                               
   Islets, Pancreatic                                 (46)         (50)         (50)         (49)                                   
      Atrophy                                                                                 1 [4.0]                               
      Hyperplasia                                     34 [2.2]     32 [2.4]     26 [2.3]     13 [1.8]                               
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Average severity grade (1-minimal;2-mild;3-moderate;4-marked)                                                                    
                                                                                                                                    
                                                             Page    9                                                              
                                                                                                                                   
NTP Experiment-Test: 96017-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT18  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 05/19/04    
Route: DOSED WATER                            WATER DISINFECTION BYPRODUCTS (DIBROMOACETIC ACID)                  Time: 09:37:47    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE MALE                             0 MG/L       50 MG/L      500 MG/L     1000                                   
                                                                                             MG/L                                   
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ENDOCRINE SYSTEM - CONT                                                                                                             
   Parathyroid Gland                                  (45)         (47)         (49)         (47)                                   
      Cyst                                                          2 [2.5]      3 [3.0]      4 [3.0]                               
   Pituitary Gland                                    (45)         (50)         (48)         (48)                                   
      Pars Distalis, Cyst                              7 [3.0]      7 [3.0]      7 [3.0]      5 [3.0]                               
      Pars Distalis, Hyperplasia, Focal                1 [3.0]                   1 [1.0]                                            
   Thyroid Gland                                      (48)         (50)         (50)         (50)                                   
      Degeneration, Cystic                             5 [2.0]      8 [1.6]      3 [1.7]      6 [1.8]                               
      Follicular Cell, Hyperplasia                     3 [1.0]                                                                      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Epididymis                                         (49)         (50)         (50)         (50)                                   
      Atypia Cellular                                  5 [2.4]      4 [2.5]      2 [2.0]      6 [2.3]                               
      Granuloma Sperm                                  1 [4.0]      2 [3.5]      2 [3.5]      2 [2.5]                               
      Spermatocele                                     1 [3.0]                                1 [3.0]                               
   Preputial Gland                                    (49)         (50)         (50)         (50)                                   
      Cyst                                            25 [2.9]     26 [3.0]     33 [3.0]     33 [3.0]                               
      Inflammation, Chronic                           21 [2.1]     30 [2.3]     24 [2.3]     28 [2.2]                               
   Prostate                                           (48)         (50)         (50)         (49)                                   
      Inflammation, Chronic                                         4 [2.8]                   1 [3.0]                               
   Seminal Vesicle                                    (49)         (50)         (50)         (50)                                   
      Degeneration                                     3 [3.0]      5 [3.0]      1 [3.0]                                            
      Inflammation, Chronic                            1 [3.0]                                                                      
   Testes                                             (49)         (50)         (50)         (50)                                   
      Germinal Epithelium, Atrophy                     9 [2.1]      4 [2.0]      4 [1.5]      8 [1.9]                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (47)         (50)         (50)         (50)                                   
      Angiectasis                                                                             1 [2.0]                               
      Depletion Cellular                               1 [2.0]                                                                      
      Hyperplasia                                     22 [2.5]     22 [2.7]     28 [2.7]     32 [2.6]                               
   Lymph Node                                         (1)          (2)          (5)          (1)                                    
      Bronchial, Hyperplasia, Lymphoid                                           1 [3.0]                                            
      Iliac, Ectasia                                                1 [2.0]                                                         
      Inguinal, Hyperplasia, Lymphoid                                            1 [3.0]                                            
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Average severity grade (1-minimal;2-mild;3-moderate;4-marked)                                                                    
                                                                                                                                    
                                                             Page   10                                                              
                                                                                                                                   
NTP Experiment-Test: 96017-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT18  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 05/19/04    
Route: DOSED WATER                            WATER DISINFECTION BYPRODUCTS (DIBROMOACETIC ACID)                  Time: 09:37:47    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE MALE                             0 MG/L       50 MG/L      500 MG/L     1000                                   
                                                                                             MG/L                                   
____________________________________________________________________________________________________________________________________
                                                                                                                                    
HEMATOPOIETIC SYSTEM - CONT                                                                                                         
      Inguinal, Pigmentation                                        1 [3.0]                                                         
      Mediastinal, Hyperplasia, Lymphoid               1 [3.0]                   1 [3.0]                                            
      Mediastinal, Pigmentation                                                               1 [3.0]                               
      Pancreatic, Hyperplasia, Lymphoid                                          1 [3.0]                                            
   Lymph Node, Mandibular                             (48)         (50)         (48)         (48)                                   
      Atrophy                                          5 [2.4]      2 [2.5]      3 [2.0]      7 [2.1]                               
      Hematopoietic Cell Proliferation                 1 [2.0]                                                                      
      Hemorrhage                                       1 [2.0]                   1 [2.0]                                            
      Hyperplasia, Lymphoid                           15 [2.5]     14 [2.2]      6 [2.5]      7 [2.3]                               
      Pigmentation                                     7 [2.1]      8 [2.0]      1 [2.0]      7 [2.1]                               
   Lymph Node, Mesenteric                             (46)         (49)         (49)         (47)                                   
      Atrophy                                          4 [2.5]      2 [2.5]      1 [2.0]      9 [2.3]                               
      Hematopoietic Cell Proliferation                 1 [2.0]      1 [1.0]      3 [1.7]      3 [2.0]                               
      Hemorrhage                                       8 [1.9]      5 [2.0]      9 [1.7]      7 [2.0]                               
      Hyperplasia, Lymphoid                            2 [2.5]      8 [2.5]      3 [2.7]      6 [2.5]                               
      Hyperplasia, Plasma Cell                                                   1 [3.0]                                            
   Spleen                                             (47)         (50)         (50)         (50)                                   
      Angiectasis                                                                             1 [2.0]                               
      Hematopoietic Cell Proliferation                18 [3.1]     20 [2.6]     28 [2.8]     38 [2.9]                               
      Pigmentation                                                  1 [2.0]      1 [3.0]      1 [2.0]                               
      Lymphoid Follicle, Atrophy                       4 [2.5]      7 [2.7]      3 [2.7]      8 [2.8]                               
      Lymphoid Follicle, Hyperplasia                   3 [2.3]      6 [2.5]      6 [2.7]      6 [2.3]                               
   Thymus                                             (42)         (45)         (46)         (47)                                   
      Atrophy                                         14 [3.1]     16 [2.9]     12 [2.8]     22 [3.0]                               
      Hyperplasia, Lymphoid                                         1 [3.0]      1 [3.0]      1 [4.0]                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Skin                                               (49)         (50)         (50)         (50)                                   
      Cyst Epithelial Inclusion                                     2 [3.0]                                                         
      Ulcer                                            3 [4.0]      2 [4.0]                   3 [4.0]                               
      Epidermis, Hyperplasia                           3 [2.0]      2 [2.5]                   3 [3.3]                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (49)         (50)         (50)         (50)                                   
      Hyperostosis                                                  1 [2.0]                                                         
      Cranium, Hyperostosis                            1 [3.0]                                1 [3.0]                               
   Skeletal Muscle                                    (1)          (1)                       (1)                                    
      Atrophy                                                       1 [1.0]                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Average severity grade (1-minimal;2-mild;3-moderate;4-marked)                                                                    
                                                                                                                                    
                                                             Page   11                                                              
                                                                                                                                   
NTP Experiment-Test: 96017-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT18  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 05/19/04    
Route: DOSED WATER                            WATER DISINFECTION BYPRODUCTS (DIBROMOACETIC ACID)                  Time: 09:37:47    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE MALE                             0 MG/L       50 MG/L      500 MG/L     1000                                   
                                                                                             MG/L                                   
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Peripheral Nerve                                   (2)          (2)          (1)                                                 
      Atrophy                                                       1 [1.0]      1 [3.0]                                            
   Spinal Cord                                        (2)          (2)          (1)                                                 
      Gliosis                                          1 [3.0]                                                                      
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Lung                                               (49)         (50)         (50)         (50)                                   
      Edema                                            2 [2.0]                   1 [3.0]      2 [2.0]                               
      Hemorrhage                                       2 [2.5]                                4 [1.5]                               
      Hyperplasia, Lymphoid                            3 [2.7]                   1 [2.0]                                            
      Infiltration Cellular, Histiocyte                2 [1.0]      6 [2.3]      3 [2.3]      6 [3.2]                               
      Metaplasia, Osseous                              1 [1.0]      2 [1.0]                   1 [1.0]                               
      Alveolar Epithelium, Hyperplasia                 2 [1.5]      6 [1.7]      6 [2.3]      7 [1.9]                               
      Bronchiole, Hyperplasia                                                                 1 [1.0]                               
   Nose                                               (48)         (50)         (50)         (50)                                   
      Foreign Body                                                               1                                                  
      Inflammation, Chronic                            1 [2.0]      1 [3.0]      3 [2.0]                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                (49)         (50)         (50)         (50)                                   
      Atrophy                                                       1 [4.0]                                                         
      Cataract                                                      1 [2.0]      1 [1.0]      5 [1.4]                               
      Inflammation, Chronic                                                      2 [1.5]      2 [2.0]                               
      Bilateral, Cataract                                                                     1 [3.0]                               
      Cornea, Hyperplasia                                                        1 [2.0]      1 [2.0]                               
   Harderian Gland                                    (49)         (50)         (50)         (50)                                   
      Cyst                                                          1 [3.0]                                                         
      Hyperplasia, Focal                               5 [2.6]      1 [4.0]      1 [3.0]      1 [3.0]                               
   Lacrimal Gland                                                  (1)                                                              
      Cyst                                                          1 [3.0]                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (49)         (50)         (50)         (50)                                   
      Cyst                                             9 [3.0]     13 [3.0]     14 [3.0]     11 [3.0]                               
      Hydronephrosis                                   4 [2.0]      2 [2.5]                   4 [2.5]                               
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Average severity grade (1-minimal;2-mild;3-moderate;4-marked)                                                                    
                                                                                                                                    
                                                             Page   12                                                              
                                                                                                                                   
NTP Experiment-Test: 96017-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT18  
Study Type: CHRONIC                                  WITH AVERAGE SEVERITY GRADES[b]                              Date: 05/19/04    
Route: DOSED WATER                            WATER DISINFECTION BYPRODUCTS (DIBROMOACETIC ACID)                  Time: 09:37:47    
____________________________________________________________________________________________________________________________________
                                                                                                                                    
         B6C3F1 MICE MALE                             0 MG/L       50 MG/L      500 MG/L     1000                                   
                                                                                             MG/L                                   
____________________________________________________________________________________________________________________________________
                                                                                                                                    
URINARY SYSTEM - CONT                                                                                                               
      Hyperplasia, Lymphoid                            5 [2.6]      5 [2.0]      6 [2.3]      5 [2.4]                               
      Infarct                                          3 [1.7]      7 [2.3]      4 [2.0]      5 [1.8]                               
      Inflammation, Suppurative                                     1 [3.0]                   1 [4.0]                               
      Metaplasia, Osseous                              6 [2.2]      3 [2.3]      2 [2.0]      2 [3.0]                               
      Nephropathy                                     36 [1.8]     44 [1.5]     42 [1.7]     39 [1.8]                               
      Papilla, Necrosis                                                                       1 [3.0]                               
      Renal Tubule, Accumulation, Hyaline Droplet                                1 [3.0]                                            
      Renal Tubule, Dilatation                         1 [3.0]      3 [2.3]                   1 [3.0]                               
      Renal Tubule, Hyperplasia                        1 [2.0]      1 [1.0]      1 [1.0]      3 [1.7]                               
      Renal Tubule, Necrosis                           1 [2.0]                                                                      
      Renal Tubule, Pigmentation                       1 [4.0]      3 [2.7]      2 [2.5]      7 [3.0]                               
      Transitional Epithelium, Hyperplasia                                       1 [2.0]                                            
   Urethra                                                         (3)                                                              
      Angiectasis                                                   3 [4.0]                                                         
      Inflammation, Chronic Active                                  3 [2.7]                                                         
   Urinary Bladder                                    (49)         (50)         (50)         (49)                                   
      Edema                                                                      1 [3.0]                                            
      Hemorrhage                                                    1 [2.0]                                                         
      Hyperplasia, Lymphoid                                         1 [2.0]      1 [3.0]                                            
      Inflammation, Chronic                                                                   1 [2.0]                               
      Transitional Epithelium, Hyperplasia                                       1 [1.0]      1 [3.0]                               
                                                                                                                                    
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
b  Average severity grade (1-minimal;2-mild;3-moderate;4-marked)                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page   13                                                              
                                                                                                                                   
                             ------------------------------------------------------------                                           
                             ----------              END OF REPORT             ----------                                           
                             ------------------------------------------------------------                                           
NTP is located at the National Institute of Environmental Health Sciences, part of the National Institutes of Health.