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TDMS Study 05181-04 Pathology Tables

NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30

                                                           CORE STUDY




       Facility:  Battelle Northwest

       Chemical CAS #:  0109-99-9

       Lock Date:  03/24/93

       Cage Range:  All

       Reasons For Removal:    All

       Removal Date Range:     All

       Treatment Groups:       Include All




































                                                              Page   1

NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 7| 7| 7| 7| 0| 0| 0| 0| 0| 7| 7| 7| 6| 7| 7| 4| 7| 7| 7| 7| 7| 7| 5| 7|             
                             DAY ON TEST   | 3| 3| 3| 3| 3| 1| 1| 1| 1| 1| 3| 0| 3| 3| 3| 3| 9| 3| 3| 3| 3| 3| 3| 9| 3|             
                                           | 6| 6| 7| 4| 6| 9| 9| 9| 9| 9| 7| 6| 7| 0| 3| 4| 5| 6| 7| 6| 6| 7| 7| 9| 3|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   B6C3F1 MICE FEMALE                      | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1|             
    CONTROL                                | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
                                           | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 ALIMENTARY SYSTEM                         |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Esophagus                               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Gallbladder                             | +  +  +  +  +  A  A  +  A  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Degeneration, Hyaline                |                                                                          |             
      Inflammation                         |                                                                          |             
                                            __________________________________________________________________________|             
   Intestine Large, Colon                  | +  +  +  +  +  M  M  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  M  M  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Cecum                  | +  +  +  +  +  +  +  +  A  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Duodenum               | +  +  +  +  +  A  A  +  A  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Jejunum                | +  +  +  +  +  +  A  +  A  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Ileum                  | +  +  +  +  +  A  +  +  A  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Angiectasis                          |                                                                          |             
      Basophilic Focus                     |                                                                          |             
      Eosinophilic Focus                   |                                                                      X   |             
      Hemorrhage                           |                                                                          |             
      Hepatodiaphragmatic Nodule           |                                                                          |             
      Inflammation, Chronic                |                                  2                                       |             
      Necrosis                             |                                        3                             2   |             
      Pigmentation                         |                                                                          |             
      Bile Duct, Cyst                      |                                                                          |             
                                            __________________________________________________________________________|             
   Mesentery                               |                                  +                                       |             
      Fat, Necrosis                        |                                                                          |             
                                            __________________________________________________________________________|             
   Pancreas                                | +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Atrophy                              |                                                                          |             
      Cytoplasmic Alteration               |                                                                          |             
      Hypertrophy                          |                                                                          |             
                                            __________________________________________________________________________|             
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Infiltration Cellular, Mast Cell     |                                     4                                    |             
      Ulcer                                |                                     2                                    |             
      Epithelium, Hyperplasia              |                                  1                                       |             
                                            __________________________________________________________________________|             
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Erosion                              |                                                                      1   |             
      Infiltration Cellular, Mast Cell     |                                     4                                    |             
      Inflammation, Suppurative            |                                        1                                 |             
      Mineralization                       |                                        1                                 |             
 _____________________________________________________________________________________________________________________|             
 CARDIOVASCULAR SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Blood Vessel                            |                                                                          |             
      Mineralization                       |                                                                          |             
                                            __________________________________________________________________________|             
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Cardiomyopathy                       |    1  1  1                       1  1        1     1              1     1|             
      Hemorrhage                           |                                                 2                        |             
      Mineralization                       |                                                                          |             
 _____________________________________________________________________________________________________________________|             
                                                             Page   2                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 7| 7| 7| 7| 0| 0| 0| 0| 0| 7| 7| 7| 6| 7| 7| 4| 7| 7| 7| 7| 7| 7| 5| 7|             
                             DAY ON TEST   | 3| 3| 3| 3| 3| 1| 1| 1| 1| 1| 3| 0| 3| 3| 3| 3| 9| 3| 3| 3| 3| 3| 3| 9| 3|             
                                           | 6| 6| 7| 4| 6| 9| 9| 9| 9| 9| 7| 6| 7| 0| 3| 4| 5| 6| 7| 6| 6| 7| 7| 9| 3|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   B6C3F1 MICE FEMALE                      | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1|             
    CONTROL                                | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
                                           | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 CARDIOVASCULAR SYSTEM - cont              |                                                                          |             
                                           |                                                                          |             
      Artery, Inflammation                 |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM                          |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hyperplasia                          |                                                                   2      |             
      Hypertrophy                          |                                                                          |             
      Necrosis                             |                                                                          |             
      Capsule, Hyperplasia                 |                                                                          |             
                                            __________________________________________________________________________|             
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hyperplasia                          |                                                                         2|             
      Necrosis                             |                                                                          |             
                                            __________________________________________________________________________|             
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Parathyroid Gland                       | +  M  +  +  +  M  +  M  M  I  +  +  M  +  M  +  +  +  M  M  +  +  M  M  M|             
                                            __________________________________________________________________________|             
   Pituitary Gland                         | +  +  +  +  +  +  +  +  +  +  I  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hyperplasia                          |                                                                          |             
      Pars Distalis, Hyperplasia           | 4        2  3                                               2     2     1|             
      Pars Intermedia, Hyperplasia         |                                                                          |             
                                            __________________________________________________________________________|             
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Angiectasis                          |       1                                                                  |             
      Inflammation                         |                                                                          |             
      Follicular Cell, Hyperplasia         | 1  1  4  1                    4        1     1        1  1              1|             
 _____________________________________________________________________________________________________________________|             
 GENERAL BODY SYSTEM                       |                                                                          |             
                                           |                                                                          |             
    None                                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 GENITAL SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Clitoral Gland                          | +  M  +  +  +  M  +  +  M  +  +  +  +  +  M  +  +  +  M  +  +  +  +  M  +|             
      Inflammation                         |                                                                          |             
                                            __________________________________________________________________________|             
   Ovary                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Amyloid Deposition                   |                                                 2                        |             
      Angiectasis                          |                                                                         2|             
      Atrophy                              |    2     3  2                                      3                     |             
      Cyst                                 | 4     2     2                    3           2     1  1     3  3     1  1|             
      Hyperplasia                          |                               3                                          |             
      Granulosa Cell, Hyperplasia          |                                                                          |             
                                            __________________________________________________________________________|             
   Uterus                                  | +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Angiectasis                          | 3                                                                        |             
      Hydrometra                           |                                     2                    4               |             
      Hyperplasia, Cystic                  | 1  3  1  2  2                 2  2  2     1  2     2  2  2     2  3  2  1|             
      Inflammation, Suppurative            |             2                                                            |             
      Endometrium, Hyperplasia             |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone Marrow                             | +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
                                                             Page   3                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 7| 7| 7| 7| 0| 0| 0| 0| 0| 7| 7| 7| 6| 7| 7| 4| 7| 7| 7| 7| 7| 7| 5| 7|             
                             DAY ON TEST   | 3| 3| 3| 3| 3| 1| 1| 1| 1| 1| 3| 0| 3| 3| 3| 3| 9| 3| 3| 3| 3| 3| 3| 9| 3|             
                                           | 6| 6| 7| 4| 6| 9| 9| 9| 9| 9| 7| 6| 7| 0| 3| 4| 5| 6| 7| 6| 6| 7| 7| 9| 3|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   B6C3F1 MICE FEMALE                      | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1|             
    CONTROL                                | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
                                           | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM - cont               |                                                                          |             
                                           |                                                                          |             
      Angiectasis                          |                                        3                                 |             
      Hyperplasia, Histiocytic             |                                                          2               |             
                                            __________________________________________________________________________|             
   Lymph Node                              |                                                          +           +   |             
      Iliac, Hyperplasia                   |                                                          2               |             
      Lumbar, Hyperplasia                  |                                                                      1   |             
                                            __________________________________________________________________________|             
   Lymph Node, Bronchial                   | +  +  +  +  +  M  M  +  M  M  +  M  +  +  +  +  M  +  M  +  +  +  M  M  M|             
      Hyperplasia                          |                                                          2               |             
                                            __________________________________________________________________________|             
   Lymph Node, Mandibular                  | +  M  M  M  +  +  +  +  +  M  M  +  M  +  +  +  +  M  +  +  +  M  +  +  +|             
      Hyperplasia                          |                                                                      2   |             
                                            __________________________________________________________________________|             
   Lymph Node, Mesenteric                  | +  +  M  +  +  M  +  +  A  M  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +|             
      Hyperplasia                          |                                                                2         |             
                                            __________________________________________________________________________|             
   Lymph Node, Mediastinal                 | +  +  +  M  +  M  M  M  M  M  +  +  M  +  M  +  +  +  +  M  +  +  +  +  +|             
      Hyperplasia                          |                                                                          |             
                                            __________________________________________________________________________|             
   Spleen                                  | +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Angiectasis                          |                                                                          |             
      Hematopoietic Cell Proliferation     |                                  2  2                                    |             
      Hyperplasia, Lymphoid                |                               2                    2     4               |             
                                            __________________________________________________________________________|             
   Thymus                                  | +  +  +  +  M  +  +  M  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  M  +|             
      Amyloid Deposition                   |                                                 4                        |             
      Atrophy                              |                3  4     3  4                                             |             
      Hyperplasia, Lymphoid                |                                                                2         |             
 _____________________________________________________________________________________________________________________|             
 INTEGUMENTARY SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Mammary Gland                           | +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hyperplasia                          |                                     2                                    |             
                                            __________________________________________________________________________|             
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Subcutaneous Tissue, Edema           |                                                 4                        |             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM                    |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Fibrous Osteodystrophy               | 2     1  1  2                    1  2           1  1     1     2        1|             
                                            __________________________________________________________________________|             
   Skeletal Muscle                         |                                                                +         |             
 _____________________________________________________________________________________________________________________|             
 NERVOUS SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Meninges, Infiltration Cellular,     |                                                                          |             
           Mononuclear Cell                |                                                                1         |             
 _____________________________________________________________________________________________________________________|             
 RESPIRATORY SYSTEM                        |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Infiltration Cellular, Histiocyte    |                                                                          |             
      Inflammation, Chronic, Focal         |                                                                      2   |             
      Alveolar Epithelium, Hyperplasia     |                                                    2                     |             
 _____________________________________________________________________________________________________________________|             
                                                             Page   4                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 7| 7| 7| 7| 0| 0| 0| 0| 0| 7| 7| 7| 6| 7| 7| 4| 7| 7| 7| 7| 7| 7| 5| 7|             
                             DAY ON TEST   | 3| 3| 3| 3| 3| 1| 1| 1| 1| 1| 3| 0| 3| 3| 3| 3| 9| 3| 3| 3| 3| 3| 3| 9| 3|             
                                           | 6| 6| 7| 4| 6| 9| 9| 9| 9| 9| 7| 6| 7| 0| 3| 4| 5| 6| 7| 6| 6| 7| 7| 9| 3|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   B6C3F1 MICE FEMALE                      | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1|             
    CONTROL                                | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
                                           | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 RESPIRATORY SYSTEM - cont                 |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Nasolacrimal Duct, Inflammation,     |                                                                          |             
           Suppurative                     |                                                                          |             
                                            __________________________________________________________________________|             
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 SPECIAL SENSES SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Harderian Gland                         |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Amyloid Deposition                   |                                                 4                        |             
      Glomerulosclerosis                   |                                                                          |             
      Hyperplasia, Lymphoid                |                                  2                       2               |             
      Metaplasia, Osseous                  |                                                          1               |             
      Nephropathy                          |       1     1                    1     1                    1  1  1     1|             
      Pigmentation                         |                                                                          |             
                                            __________________________________________________________________________|             
   Urinary Bladder                         | +  +  +  +  +  +  +  M  A  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
                                                             Page   5                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 7| 6| 7| 7| 6| 7| 7| 5| 6| 7| 5| 4| 7| 4| 5| 7| 7| 6| 7| 7| 4| 6| 7| 7|            |
                             DAY ON TEST   | 0| 3| 8| 3| 3| 0| 3| 3| 0| 5| 3| 7| 7| 3| 4| 7| 3| 3| 4| 3| 3| 4| 5| 3| 3|            |
                                           | 8| 7| 0| 3| 3| 4| 6| 3| 2| 1| 3| 4| 8| 3| 2| 2| 6| 3| 8| 4| 4| 2| 2| 3| 4|      T (*) |
 _____________________________________________________________________________________________________________________|            |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      O     |
   B6C3F1 MICE FEMALE                      | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      T     |
                               ANIMAL ID   | 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1|      A     |
    CONTROL                                | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|      L     |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 ALIMENTARY SYSTEM                         |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Esophagus                               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Gallbladder                             | +  +  +  +  +  +  +  +  +  +  +  +  +  I  +  +  +  +  +  +  +  +  +  +  +|  45        |
      Degeneration, Hyaline                |                                                                   2      |      1  2.0|
      Inflammation                         | 1                                                                        |      1  1.0|
                                            __________________________________________________________________________|____________|
   Intestine Large, Colon                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +|  46        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  M  +  +  +  +  +  M  +  A  +  +  +  +  +  +  +  +  +|  44        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Cecum                  | +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  A  +  +  +  M  +  +  +  +  +|  45        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Duodenum               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +|  45        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Jejunum                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  A  +  +  +  +  +  +|  45        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Ileum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +|  46        |
                                            __________________________________________________________________________|____________|
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Angiectasis                          |                                  3                                       |      1  3.0|
      Basophilic Focus                     |                                                 X                        |      1     |
      Eosinophilic Focus                   |                            X  3        3        X     X              X   |      7  3.0|
      Hemorrhage                           |       2                                                                  |      1  2.0|
      Hepatodiaphragmatic Nodule           | 2                                                                        |      1  2.0|
      Inflammation, Chronic                |                                                                          |      1  2.0|
      Necrosis                             |                                     1                                    |      3  2.0|
      Pigmentation                         |                                  3                                       |      1  3.0|
      Bile Duct, Cyst                      | 1                                                                        |      1  1.0|
                                            __________________________________________________________________________|____________|
   Mesentery                               |       +  +                                   +        +     +            |   6        |
      Fat, Necrosis                        |       2  3                                            2                  |      3  2.3|
                                            __________________________________________________________________________|____________|
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +|  48        |
      Atrophy                              |                            1                                             |      1  1.0|
      Cytoplasmic Alteration               |                            1                                             |      1  1.0|
      Hypertrophy                          |                                                 1                        |      1  1.0|
                                            __________________________________________________________________________|____________|
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Infiltration Cellular, Mast Cell     |                                                                          |      1  4.0|
      Ulcer                                |                                                       1           1      |      3  1.3|
      Epithelium, Hyperplasia              |       1                                                                  |      2  1.0|
                                            __________________________________________________________________________|____________|
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Erosion                              |                         2                                                |      2  1.5|
      Infiltration Cellular, Mast Cell     |                                                                          |      1  4.0|
      Inflammation, Suppurative            |                                                                          |      1  1.0|
      Mineralization                       |                                                                          |      1  1.0|
 _____________________________________________________________________________________________________________________|            |
 CARDIOVASCULAR SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Blood Vessel                            |                                                       +                  |   1        |
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page   6                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 7| 6| 7| 7| 6| 7| 7| 5| 6| 7| 5| 4| 7| 4| 5| 7| 7| 6| 7| 7| 4| 6| 7| 7|            |
                             DAY ON TEST   | 0| 3| 8| 3| 3| 0| 3| 3| 0| 5| 3| 7| 7| 3| 4| 7| 3| 3| 4| 3| 3| 4| 5| 3| 3|            |
                                           | 8| 7| 0| 3| 3| 4| 6| 3| 2| 1| 3| 4| 8| 3| 2| 2| 6| 3| 8| 4| 4| 2| 2| 3| 4|      T (*) |
 _____________________________________________________________________________________________________________________|            |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      O     |
   B6C3F1 MICE FEMALE                      | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      T     |
                               ANIMAL ID   | 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1|      A     |
    CONTROL                                | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|      L     |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 CARDIOVASCULAR SYSTEM - cont              |                                                                          |            |
                                           |                                                                          |            |
      Mineralization                       |                                                       2                  |      1  2.0|
                                            __________________________________________________________________________|____________|
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Cardiomyopathy                       | 1     1           1  1                       1  1     1     1            |     17  1.0|
      Hemorrhage                           |                                                                          |      1  2.0|
      Mineralization                       |       1                                                                  |      1  1.0|
      Artery, Inflammation                 |                                                                2         |      1  2.0|
 _____________________________________________________________________________________________________________________|            |
 ENDOCRINE SYSTEM                          |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hyperplasia                          |             3                                                            |      2  2.5|
      Hypertrophy                          |       1                    1                                         3   |      3  1.7|
      Necrosis                             |                                                       4                  |      1  4.0|
      Capsule, Hyperplasia                 |                                                             4            |      1  4.0|
                                            __________________________________________________________________________|____________|
   Adrenal Medulla                         | +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Hyperplasia                          |       1                    1                                      1      |      4  1.3|
      Necrosis                             |                                                       4                  |      1  4.0|
                                            __________________________________________________________________________|____________|
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +|  48        |
                                            __________________________________________________________________________|____________|
   Parathyroid Gland                       | +  M  +  +  +  M  +  +  +  +  +  M  +  +  +  M  M  +  M  I  M  +  +  +  +|  30        |
                                            __________________________________________________________________________|____________|
   Pituitary Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  M  +|  47        |
      Hyperplasia                          |                               1                                          |      1  1.0|
      Pars Distalis, Hyperplasia           |             2        4           4           1  4  3        2           2|     14  2.6|
      Pars Intermedia, Hyperplasia         |          1                                                               |      1  1.0|
                                            __________________________________________________________________________|____________|
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Angiectasis                          |                                                                          |      1  1.0|
      Inflammation                         |                                                                2         |      1  2.0|
      Follicular Cell, Hyperplasia         |                      1                             1        2           1|     14  1.5|
 _____________________________________________________________________________________________________________________|            |
 GENERAL BODY SYSTEM                       |                                                                          |            |
                                           |                                                                          |            |
    None                                   |                                                                          |            |
 _____________________________________________________________________________________________________________________|            |
 GENITAL SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Clitoral Gland                          | +  +  M  +  +  M  +  +  +  +  +  M  +  +  +  +  +  M  +  M  +  +  M  +  +|  38        |
      Inflammation                         |                   4                                                      |      1  4.0|
                                            __________________________________________________________________________|____________|
   Ovary                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +|  49        |
      Amyloid Deposition                   |                                                                          |      1  2.0|
      Angiectasis                          |                                  2                                3      |      3  2.3|
      Atrophy                              |             3              3                    2                 3      |      8  2.6|
      Cyst                                 | 2           3  1           3              2     2  2                 1   |     19  2.1|
      Hyperplasia                          |                                                                          |      1  3.0|
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page   7                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 7| 6| 7| 7| 6| 7| 7| 5| 6| 7| 5| 4| 7| 4| 5| 7| 7| 6| 7| 7| 4| 6| 7| 7|            |
                             DAY ON TEST   | 0| 3| 8| 3| 3| 0| 3| 3| 0| 5| 3| 7| 7| 3| 4| 7| 3| 3| 4| 3| 3| 4| 5| 3| 3|            |
                                           | 8| 7| 0| 3| 3| 4| 6| 3| 2| 1| 3| 4| 8| 3| 2| 2| 6| 3| 8| 4| 4| 2| 2| 3| 4|      T (*) |
 _____________________________________________________________________________________________________________________|            |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      O     |
   B6C3F1 MICE FEMALE                      | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      T     |
                               ANIMAL ID   | 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1|      A     |
    CONTROL                                | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|      L     |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 GENITAL SYSTEM - cont                     |                                                                          |            |
                                           |                                                                          |            |
      Granulosa Cell, Hyperplasia          |                   1                                                      |      1  1.0|
                                            __________________________________________________________________________|____________|
   Uterus                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Angiectasis                          |                                                                          |      1  3.0|
      Hydrometra                           |                         1                                                |      3  2.3|
      Hyperplasia, Cystic                  | 1  2  2  1  1  3  2  2  2  2  3  2  2  2  2  1     2  2  2  2  2  2  2  3|     41  1.9|
      Inflammation, Suppurative            |                                                                          |      1  2.0|
      Endometrium, Hyperplasia             |                                                 2                        |      1  2.0|
 _____________________________________________________________________________________________________________________|            |
 HEMATOPOIETIC SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Angiectasis                          |                                                                          |      1  3.0|
      Hyperplasia, Histiocytic             |                                                             2            |      2  2.0|
                                            __________________________________________________________________________|____________|
   Lymph Node                              |                +                 +           +                           |   5        |
      Iliac, Hyperplasia                   |                                  2                                       |      2  2.0|
      Lumbar, Hyperplasia                  |                                                                          |      1  1.0|
                                            __________________________________________________________________________|____________|
   Lymph Node, Bronchial                   | +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  M  +  M  +|  36        |
      Hyperplasia                          |                                                                          |      1  2.0|
                                            __________________________________________________________________________|____________|
   Lymph Node, Mandibular                  | +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +|  40        |
      Hyperplasia                          |                               2  2     2                       2         |      5  2.0|
                                            __________________________________________________________________________|____________|
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  45        |
      Hyperplasia                          |          2                                                               |      2  2.0|
                                            __________________________________________________________________________|____________|
   Lymph Node, Mediastinal                 | +  +  +  +  +  +  M  M  +  +  +  +  +  M  +  +  +  +  +  M  +  +  +  +  +|  37        |
      Hyperplasia                          |          3                                                     2     2   |      3  2.3|
                                            __________________________________________________________________________|____________|
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Angiectasis                          |                                  4                                       |      1  4.0|
      Hematopoietic Cell Proliferation     |       3        3           2        2        2        2  2        2      |     10  2.2|
      Hyperplasia, Lymphoid                |                                                             2            |      4  2.5|
                                            __________________________________________________________________________|____________|
   Thymus                                  | +  +  +  +  +  M  +  +  +  +  +  +  +  M  M  +  +  +  M  +  +  M  +  M  +|  40        |
      Amyloid Deposition                   |                                                                          |      1  4.0|
      Atrophy                              |       3                                                                  |      5  3.4|
      Hyperplasia, Lymphoid                |                                                                          |      1  2.0|
 _____________________________________________________________________________________________________________________|            |
 INTEGUMENTARY SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Mammary Gland                           | +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
      Hyperplasia                          |                                                                          |      1  2.0|
                                            __________________________________________________________________________|____________|
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +|  49        |
      Subcutaneous Tissue, Edema           |                                                                          |      1  4.0|
 _____________________________________________________________________________________________________________________|            |
 MUSCULOSKELETAL SYSTEM                    |                                                                          |            |
                                           |                                                                          |            |
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page   8                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 7| 6| 7| 7| 6| 7| 7| 5| 6| 7| 5| 4| 7| 4| 5| 7| 7| 6| 7| 7| 4| 6| 7| 7|            |
                             DAY ON TEST   | 0| 3| 8| 3| 3| 0| 3| 3| 0| 5| 3| 7| 7| 3| 4| 7| 3| 3| 4| 3| 3| 4| 5| 3| 3|            |
                                           | 8| 7| 0| 3| 3| 4| 6| 3| 2| 1| 3| 4| 8| 3| 2| 2| 6| 3| 8| 4| 4| 2| 2| 3| 4|      T (*) |
 _____________________________________________________________________________________________________________________|            |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      O     |
   B6C3F1 MICE FEMALE                      | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      T     |
                               ANIMAL ID   | 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1|      A     |
    CONTROL                                | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|      L     |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 MUSCULOSKELETAL SYSTEM - cont             |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Fibrous Osteodystrophy               |             1     2           2     1              2     1           1  1|     19  1.4|
                                            __________________________________________________________________________|____________|
   Skeletal Muscle                         |                                                                      +   |   2        |
 _____________________________________________________________________________________________________________________|            |
 NERVOUS SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Meninges, Infiltration Cellular,     |                                                                          |            |
           Mononuclear Cell                |                                                                          |      1  1.0|
 _____________________________________________________________________________________________________________________|            |
 RESPIRATORY SYSTEM                        |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Infiltration Cellular, Histiocyte    |    1                          3                                          |      2  2.0|
      Inflammation, Chronic, Focal         |                               2                                          |      2  2.0|
      Alveolar Epithelium, Hyperplasia     |                               4                                          |      2  3.0|
                                            __________________________________________________________________________|____________|
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Nasolacrimal Duct, Inflammation,     |                                                                          |            |
           Suppurative                     |    1                                                                     |      1  1.0|
                                            __________________________________________________________________________|____________|
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 SPECIAL SENSES SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Harderian Gland                         |    +           +              +           +                              |   4        |
 _____________________________________________________________________________________________________________________|            |
 URINARY SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Amyloid Deposition                   |                                                                          |      1  4.0|
      Glomerulosclerosis                   |                                  3                                       |      1  3.0|
      Hyperplasia, Lymphoid                |                                                                          |      2  2.0|
      Metaplasia, Osseous                  |                                                                          |      1  1.0|
      Nephropathy                          |          1  1        1  1           1                    2        2  1  1|     17  1.1|
      Pigmentation                         |                                  3                                       |      1  3.0|
                                            __________________________________________________________________________|____________|
   Urinary Bladder                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  47        |
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page   9                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 6| 1| 7| 7| 6| 6| 7| 7| 7| 7| 7| 7| 7| 6| 6| 5| 7| 7| 7| 7| 7| 5| 6| 7|             
                             DAY ON TEST   | 3| 3| 3| 3| 3| 8| 4| 3| 3| 3| 3| 3| 3| 3| 9| 9| 2| 3| 3| 3| 3| 3| 0| 3| 3|             
                                           | 3| 0| 4| 6| 4| 0| 0| 6| 7| 4| 3| 4| 3| 7| 8| 0| 6| 4| 4| 4| 6| 4| 4| 5| 3|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   B6C3F1 MICE FEMALE                      | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3|             
    200 PPM                                | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
                                           | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 ALIMENTARY SYSTEM                         |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Esophagus                               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Gallbladder                             | +  +  +  +  +  +  A  +  +  +  +  +  +  +  A  +  +  +  M  +  +  +  +  A  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Colon                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  M  +  +  +  A  +  +  +  +  +  +  +  +  A  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Cecum                  | +  +  +  +  +  +  A  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  A  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Duodenum               | +  +  +  +  +  +  A  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  A  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Jejunum                | +  +  +  +  +  +  A  +  +  M  +  +  +  +  A  +  +  +  +  +  +  +  +  A  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Ileum                  | +  +  +  +  +  +  A  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  A  +|             
                                            __________________________________________________________________________|             
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Angiectasis                          |                                                                          |             
      Clear Cell Focus                     |                         X                                                |             
      Eosinophilic Focus                   | 3                 X                 X                       X            |             
      Hematopoietic Cell Proliferation     |                                                                          |             
      Inflammation, Chronic                |                                                             2            |             
      Mixed Cell Focus                     |    X                                            X                        |             
      Vacuolization Cytoplasmic, Focal     |                                                                          |             
      Bile Duct, Cyst                      |                                                                         2|             
                                            __________________________________________________________________________|             
   Mesentery                               | +                 +                    +     +                       +   |             
      Fat, Necrosis                        | 2                 2                          2                           |             
                                            __________________________________________________________________________|             
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +|             
      Atrophy                              |             1                                            3               |             
      Cytoplasmic Alteration               |                                                                          |             
      Hyperplasia                          |                                                                          |             
      Hypertrophy                          |                                                                          |             
      Duct, Cyst                           |                                                          4               |             
                                            __________________________________________________________________________|             
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +|             
      Ulcer                                |                                                                          |             
                                            __________________________________________________________________________|             
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  A  +|             
      Inflammation, Suppurative            |                                                                          |             
      Ulcer                                |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 CARDIOVASCULAR SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Cardiomyopathy                       | 1  1     1  1     1     1        1  1  1  1           1  1  1  1        1|             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM                          |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hyperplasia                          |                                                    2                     |             
      Hypertrophy                          |                               1                                          |             
      Capsule, Hyperplasia                 |                                                                          |             
                                            __________________________________________________________________________|             
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  I  +|             
      Hyperplasia                          |                               1  3                                       |             
                                            __________________________________________________________________________|             
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +|             
 _____________________________________________________________________________________________________________________|             
                                                             Page  10                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 6| 1| 7| 7| 6| 6| 7| 7| 7| 7| 7| 7| 7| 6| 6| 5| 7| 7| 7| 7| 7| 5| 6| 7|             
                             DAY ON TEST   | 3| 3| 3| 3| 3| 8| 4| 3| 3| 3| 3| 3| 3| 3| 9| 9| 2| 3| 3| 3| 3| 3| 0| 3| 3|             
                                           | 3| 0| 4| 6| 4| 0| 0| 6| 7| 4| 3| 4| 3| 7| 8| 0| 6| 4| 4| 4| 6| 4| 4| 5| 3|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   B6C3F1 MICE FEMALE                      | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3|             
    200 PPM                                | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
                                           | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM - cont                   |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Parathyroid Gland                       | +  M  M  +  M  +  M  +  +  M  M  +  +  +  +  +  +  +  +  +  M  M  M  M  +|             
                                            __________________________________________________________________________|             
   Pituitary Gland                         | +  +  +  I  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Pars Distalis, Hyperplasia           |                   2                 2        2  2              4        2|             
      Pars Intermedia, Hyperplasia         |                                                    3                    1|             
                                            __________________________________________________________________________|             
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Follicular Cell, Hyperplasia         |                                           2     1  1  2                  |             
 _____________________________________________________________________________________________________________________|             
 GENERAL BODY SYSTEM                       |                                                                          |             
                                           |                                                                          |             
    None                                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 GENITAL SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Clitoral Gland                          | +  +  M  M  +  +  M  +  M  +  +  M  +  +  +  +  +  +  +  M  +  +  +  +  +|             
      Inflammation                         |                                                                          |             
                                            __________________________________________________________________________|             
   Ovary                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Atrophy                              |          2                       2                             2         |             
      Cyst                                 |    1                 2     4                       1        3            |             
      Interstitial Cell, Hyperplasia       |             2                                                            |             
                                            __________________________________________________________________________|             
   Uterus                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Angiectasis                          |          3                                                               |             
      Hydrometra                           |             1                             3                              |             
      Hyperplasia, Cystic                  | 2  1     3        1  3  1  3     1     2  2  2  2  2  1  2  3  2        2|             
      Thrombosis                           |                                           3                              |             
      Endometrium, Hyperplasia             |                                                    3                     |             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Infiltration Cellular, Mast Cell     |                                                       4                  |             
                                            __________________________________________________________________________|             
   Lymph Node                              |          +                                               +               |             
      Degeneration, Cystic                 |                                                          2               |             
      Hemorrhage                           |                                                                          |             
                                            __________________________________________________________________________|             
   Lymph Node, Bronchial                   | +  +  M  +  M  M  +  M  +  +  I  M  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hyperplasia                          |                                                                          |             
                                            __________________________________________________________________________|             
   Lymph Node, Mandibular                  | +  +  +  +  M  M  +  I  +  +  +  +  M  +  +  +  M  +  +  +  M  +  +  +  +|             
      Hyperplasia                          |                                                                          |             
                                            __________________________________________________________________________|             
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +|             
      Angiectasis                          |                                                                          |             
      Hematopoietic Cell Proliferation     |                                  2                                       |             
      Hyperplasia                          |                                                             2            |             
                                            __________________________________________________________________________|             
   Lymph Node, Mediastinal                 | +  M  +  +  +  +  M  +  M  +  +  +  +  I  +  M  +  +  M  M  +  +  I  +  +|             
                                            __________________________________________________________________________|             
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hematopoietic Cell Proliferation     |                   2              2                                       |             
      Hyperplasia, Lymphoid                |                                                             2            |             
      Infiltration Cellular, Mast Cell     |                                                       2                  |             
                                            __________________________________________________________________________|             
   Thymus                                  | +  M  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +|             
 _____________________________________________________________________________________________________________________|             
                                                             Page  11                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 6| 1| 7| 7| 6| 6| 7| 7| 7| 7| 7| 7| 7| 6| 6| 5| 7| 7| 7| 7| 7| 5| 6| 7|             
                             DAY ON TEST   | 3| 3| 3| 3| 3| 8| 4| 3| 3| 3| 3| 3| 3| 3| 9| 9| 2| 3| 3| 3| 3| 3| 0| 3| 3|             
                                           | 3| 0| 4| 6| 4| 0| 0| 6| 7| 4| 3| 4| 3| 7| 8| 0| 6| 4| 4| 4| 6| 4| 4| 5| 3|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   B6C3F1 MICE FEMALE                      | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3|             
    200 PPM                                | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
                                           | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM - cont               |                                                                          |             
                                           |                                                                          |             
      Atrophy                              |       3                                                                  |             
      Hyperplasia, Lymphoid                |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 INTEGUMENTARY SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Mammary Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hyperplasia                          |                               2                                          |             
                                            __________________________________________________________________________|             
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Inflammation, Suppurative            |                                                 4                        |             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM                    |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Fibrous Osteodystrophy               |    2           2        2        2     1     1     1     2  1        1  2|             
      Vertebra, Fracture                   |                                                                          |             
                                            __________________________________________________________________________|             
   Skeletal Muscle                         |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 NERVOUS SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hemorrhage                           |       2                                                                  |             
      Meninges, Infiltration Cellular,     |                                                                          |             
           Mononuclear Cell                |                                                                         1|             
                                            __________________________________________________________________________|             
   Spinal Cord                             |                                                                          |             
      Hemorrhage                           |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 RESPIRATORY SYSTEM                        |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hemorrhage                           |                                                                          |             
      Infiltration Cellular, Histiocyte    |             2                 1                                          |             
      Alveolar Epithelium, Hyperplasia     |                               1  1                 1                     |             
      Perivascular, Infiltration Cellular, |                                                                          |             
           Mononuclear Cell                |                                                                          |             
                                            __________________________________________________________________________|             
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Olfactory Epithelium, Atrophy, Focal |          1     2        1                                                |             
                                            __________________________________________________________________________|             
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 SPECIAL SENSES SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Harderian Gland                         |                                                          +               |             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +|             
      Amyloid Deposition                   |       4                                                                  |             
      Hydronephrosis                       |                                                                          |             
      Hyperplasia, Lymphoid                |             4                                                            |             
      Metaplasia, Osseous                  |                                                       1                  |             
 _____________________________________________________________________________________________________________________|             
                                                             Page  12                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 6| 1| 7| 7| 6| 6| 7| 7| 7| 7| 7| 7| 7| 6| 6| 5| 7| 7| 7| 7| 7| 5| 6| 7|             
                             DAY ON TEST   | 3| 3| 3| 3| 3| 8| 4| 3| 3| 3| 3| 3| 3| 3| 9| 9| 2| 3| 3| 3| 3| 3| 0| 3| 3|             
                                           | 3| 0| 4| 6| 4| 0| 0| 6| 7| 4| 3| 4| 3| 7| 8| 0| 6| 4| 4| 4| 6| 4| 4| 5| 3|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   B6C3F1 MICE FEMALE                      | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3|             
    200 PPM                                | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
                                           | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM - cont                     |                                                                          |             
                                           |                                                                          |             
      Nephropathy                          |             1           1        3  1  2                    1  1         |             
                                            __________________________________________________________________________|             
   Urinary Bladder                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +|             
 _____________________________________________________________________________________________________________________|             
                                                             Page  13                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 2| 7| 7| 7| 6| 7| 7| 7| 7| 5| 7| 7| 7| 5| 7| 6| 7| 7| 4| 7| 5| 7| 7| 6|            |
                             DAY ON TEST   | 3| 7| 3| 3| 3| 0| 3| 3| 3| 3| 2| 3| 3| 3| 8| 3| 0| 3| 3| 6| 3| 5| 3| 3| 5|            |
                                           | 7| 3| 3| 7| 6| 9| 3| 6| 6| 4| 5| 3| 6| 3| 2| 6| 1| 3| 3| 0| 6| 2| 6| 4| 2|      T (*) |
 _____________________________________________________________________________________________________________________|            |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      O     |
   B6C3F1 MICE FEMALE                      | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      T     |
                               ANIMAL ID   | 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3|      A     |
    200 PPM                                | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|      L     |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 ALIMENTARY SYSTEM                         |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Esophagus                               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Gallbladder                             | +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  A  +  +  +  +  +  +  +  +|  44        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Colon                  | +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  46        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Cecum                  | +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  M  +  +  +|  45        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Duodenum               | +  +  +  +  +  +  +  +  +  +  A  M  +  +  +  +  A  +  +  +  +  +  +  +  +|  44        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Jejunum                | +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  A  +  +  +  +  +  +  +  +|  44        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Ileum                  | +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  A  +  +  +  +  +  +  +  +|  45        |
                                            __________________________________________________________________________|____________|
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Angiectasis                          |                                                       2                  |      1  2.0|
      Clear Cell Focus                     |                                                                          |      1     |
      Eosinophilic Focus                   |       X        X     X              X                 X                  |      9  3.0|
      Hematopoietic Cell Proliferation     |                                                                2         |      1  2.0|
      Inflammation, Chronic                |                                                                          |      1  2.0|
      Mixed Cell Focus                     | X                                                                        |      3     |
      Vacuolization Cytoplasmic, Focal     |                                                                   2      |      1  2.0|
      Bile Duct, Cyst                      |                                                                          |      1  2.0|
                                            __________________________________________________________________________|____________|
   Mesentery                               | +        +                          +                          +         |   9        |
      Fat, Necrosis                        | 3        3                          3                                    |      6  2.5|
                                            __________________________________________________________________________|____________|
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Atrophy                              |                                                                          |      2  2.0|
      Cytoplasmic Alteration               |                                     1                                    |      1  1.0|
      Hyperplasia                          | 1                                                                        |      1  1.0|
      Hypertrophy                          |                                        1                                 |      1  1.0|
      Duct, Cyst                           |                                                                          |      1  4.0|
                                            __________________________________________________________________________|____________|
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Ulcer                                |                                                                2         |      1  2.0|
                                            __________________________________________________________________________|____________|
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
      Inflammation, Suppurative            |                            1                                             |      1  1.0|
      Ulcer                                |                2                                                         |      1  2.0|
 _____________________________________________________________________________________________________________________|            |
 CARDIOVASCULAR SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Cardiomyopathy                       | 1     1  1  1           1  1     1  1  1     1     1        1  1         |     28  1.0|
 _____________________________________________________________________________________________________________________|            |
 ENDOCRINE SYSTEM                          |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hyperplasia                          |                                                                          |      1  2.0|
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  14                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 2| 7| 7| 7| 6| 7| 7| 7| 7| 5| 7| 7| 7| 5| 7| 6| 7| 7| 4| 7| 5| 7| 7| 6|            |
                             DAY ON TEST   | 3| 7| 3| 3| 3| 0| 3| 3| 3| 3| 2| 3| 3| 3| 8| 3| 0| 3| 3| 6| 3| 5| 3| 3| 5|            |
                                           | 7| 3| 3| 7| 6| 9| 3| 6| 6| 4| 5| 3| 6| 3| 2| 6| 1| 3| 3| 0| 6| 2| 6| 4| 2|      T (*) |
 _____________________________________________________________________________________________________________________|            |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      O     |
   B6C3F1 MICE FEMALE                      | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      T     |
                               ANIMAL ID   | 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3|      A     |
    200 PPM                                | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|      L     |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 ENDOCRINE SYSTEM - cont                   |                                                                          |            |
                                           |                                                                          |            |
      Hypertrophy                          |             1                                      1              1      |      4  1.0|
      Capsule, Hyperplasia                 |                                                    2                     |      1  2.0|
                                            __________________________________________________________________________|____________|
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Hyperplasia                          |          2  1              2           2              1     3            |      8  1.9|
                                            __________________________________________________________________________|____________|
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Parathyroid Gland                       | +  M  +  M  +  +  +  +  +  +  +  I  +  +  M  +  M  +  M  +  +  M  +  +  +|  33        |
                                            __________________________________________________________________________|____________|
   Pituitary Gland                         | +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
      Pars Distalis, Hyperplasia           |                      1     2     1                                1  1  1|     12  1.8|
      Pars Intermedia, Hyperplasia         |                                                                   1      |      3  1.7|
                                            __________________________________________________________________________|____________|
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Follicular Cell, Hyperplasia         | 1                 1     1           2  2              1                  |     10  1.4|
 _____________________________________________________________________________________________________________________|            |
 GENERAL BODY SYSTEM                       |                                                                          |            |
                                           |                                                                          |            |
    None                                   |                                                                          |            |
 _____________________________________________________________________________________________________________________|            |
 GENITAL SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Clitoral Gland                          | +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  M  +  +  M|  40        |
      Inflammation                         |                                           2                              |      1  2.0|
                                            __________________________________________________________________________|____________|
   Ovary                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Atrophy                              |                            2                                3            |      5  2.2|
      Cyst                                 | 2                 2              2  3     2  1           2  2  3     1   |     15  2.1|
      Interstitial Cell, Hyperplasia       |                                                                          |      1  2.0|
                                            __________________________________________________________________________|____________|
   Uterus                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Angiectasis                          |                      2                                                   |      2  2.5|
      Hydrometra                           |                3     3                             3                     |      5  2.6|
      Hyperplasia, Cystic                  | 3     2  1     4  3  2  1  3  2  2  2  1  1  2  2  2  2  1  2  2  2  2  1|     41  2.0|
      Thrombosis                           |                                                                          |      1  3.0|
      Endometrium, Hyperplasia             |                                                                          |      1  3.0|
 _____________________________________________________________________________________________________________________|            |
 HEMATOPOIETIC SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Infiltration Cellular, Mast Cell     |                                                                          |      1  4.0|
                                            __________________________________________________________________________|____________|
   Lymph Node                              | +                                                                 +      |   4        |
      Degeneration, Cystic                 |                                                                          |      1  2.0|
      Hemorrhage                           |                                                                   4      |      1  4.0|
                                            __________________________________________________________________________|____________|
   Lymph Node, Bronchial                   | +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  M  +|  41        |
      Hyperplasia                          |          2                          2                 2                  |      3  2.0|
                                            __________________________________________________________________________|____________|
   Lymph Node, Mandibular                  | M  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +|  41        |
      Hyperplasia                          |                                                          2           3   |      2  2.5|
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  15                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 2| 7| 7| 7| 6| 7| 7| 7| 7| 5| 7| 7| 7| 5| 7| 6| 7| 7| 4| 7| 5| 7| 7| 6|            |
                             DAY ON TEST   | 3| 7| 3| 3| 3| 0| 3| 3| 3| 3| 2| 3| 3| 3| 8| 3| 0| 3| 3| 6| 3| 5| 3| 3| 5|            |
                                           | 7| 3| 3| 7| 6| 9| 3| 6| 6| 4| 5| 3| 6| 3| 2| 6| 1| 3| 3| 0| 6| 2| 6| 4| 2|      T (*) |
 _____________________________________________________________________________________________________________________|            |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      O     |
   B6C3F1 MICE FEMALE                      | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      T     |
                               ANIMAL ID   | 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3|      A     |
    200 PPM                                | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|      L     |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 HEMATOPOIETIC SYSTEM - cont               |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mesenteric                  | +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  I  +  M  +  +  +  +  +  +|  46        |
      Angiectasis                          |                                                          2               |      1  2.0|
      Hematopoietic Cell Proliferation     |                                                                          |      1  2.0|
      Hyperplasia                          |                   2        2                                             |      3  2.0|
                                            __________________________________________________________________________|____________|
   Lymph Node, Mediastinal                 | M  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  M  M  +  M  M  +|  36        |
                                            __________________________________________________________________________|____________|
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hematopoietic Cell Proliferation     |          2     2  2                                            3  2     2|      8  2.1|
      Hyperplasia, Lymphoid                |                                                                          |      1  2.0|
      Infiltration Cellular, Mast Cell     |                                                                          |      1  2.0|
                                            __________________________________________________________________________|____________|
   Thymus                                  | +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  M  +  M  +  +  +  +  +  +|  44        |
      Atrophy                              |                2                                               4         |      3  3.0|
      Hyperplasia, Lymphoid                |                   2                                                      |      1  2.0|
 _____________________________________________________________________________________________________________________|            |
 INTEGUMENTARY SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Mammary Gland                           | +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Hyperplasia                          |                                                                          |      1  2.0|
                                            __________________________________________________________________________|____________|
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Inflammation, Suppurative            |                                                                          |      1  4.0|
 _____________________________________________________________________________________________________________________|            |
 MUSCULOSKELETAL SYSTEM                    |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Fibrous Osteodystrophy               | 2     1     1        2     1     1        2  1        1  2        1  2   |     23  1.5|
      Vertebra, Fracture                   |    X                                                                     |      1     |
                                            __________________________________________________________________________|____________|
   Skeletal Muscle                         |                                                                +         |   1        |
 _____________________________________________________________________________________________________________________|            |
 NERVOUS SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hemorrhage                           |                                                                          |      1  2.0|
      Meninges, Infiltration Cellular,     |                                                                          |            |
           Mononuclear Cell                |       1                                                                  |      2  1.0|
                                            __________________________________________________________________________|____________|
   Spinal Cord                             |    +                                                                     |   1        |
      Hemorrhage                           |    4                                                                     |      1  4.0|
 _____________________________________________________________________________________________________________________|            |
 RESPIRATORY SYSTEM                        |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hemorrhage                           |                                        2                                 |      1  2.0|
      Infiltration Cellular, Histiocyte    |                                  2                                       |      3  1.7|
      Alveolar Epithelium, Hyperplasia     |                                        2                                 |      4  1.3|
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  16                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 2| 7| 7| 7| 6| 7| 7| 7| 7| 5| 7| 7| 7| 5| 7| 6| 7| 7| 4| 7| 5| 7| 7| 6|            |
                             DAY ON TEST   | 3| 7| 3| 3| 3| 0| 3| 3| 3| 3| 2| 3| 3| 3| 8| 3| 0| 3| 3| 6| 3| 5| 3| 3| 5|            |
                                           | 7| 3| 3| 7| 6| 9| 3| 6| 6| 4| 5| 3| 6| 3| 2| 6| 1| 3| 3| 0| 6| 2| 6| 4| 2|      T (*) |
 _____________________________________________________________________________________________________________________|            |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      O     |
   B6C3F1 MICE FEMALE                      | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      T     |
                               ANIMAL ID   | 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3|      A     |
    200 PPM                                | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|      L     |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 RESPIRATORY SYSTEM - cont                 |                                                                          |            |
                                           |                                                                          |            |
      Perivascular, Infiltration Cellular, |                                                                          |            |
           Mononuclear Cell                |                                                    2                     |      1  2.0|
                                            __________________________________________________________________________|____________|
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Olfactory Epithelium, Atrophy, Focal |                                                                          |      3  1.3|
                                            __________________________________________________________________________|____________|
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 SPECIAL SENSES SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Harderian Gland                         |                                                                      +   |   2        |
 _____________________________________________________________________________________________________________________|            |
 URINARY SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Amyloid Deposition                   |                                                          4               |      2  4.0|
      Hydronephrosis                       |    4                                                                     |      1  4.0|
      Hyperplasia, Lymphoid                |                                                                          |      1  4.0|
      Metaplasia, Osseous                  |                               1     1                                    |      3  1.0|
      Nephropathy                          | 1     1  1     1     1                 1     1     1  1     1            |     17  1.2|
                                            __________________________________________________________________________|____________|
   Urinary Bladder                         | M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  17                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 5| 7| 7| 7| 7| 6| 7| 7| 7| 7| 4| 6| 7| 7| 7| 6| 7| 6| 7| 0| 5| 7| 7| 7|             
                             DAY ON TEST   | 3| 5| 3| 1| 0| 3| 1| 2| 3| 3| 3| 2| 7| 3| 3| 3| 3| 3| 7| 3| 0| 6| 3| 0| 3|             
                                           | 7| 5| 4| 5| 6| 7| 0| 1| 7| 7| 4| 9| 4| 3| 7| 7| 9| 7| 0| 4| 2| 6| 3| 6| 7|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   B6C3F1 MICE FEMALE                      | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5|             
    600 PPM                                | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
                                           | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 ALIMENTARY SYSTEM                         |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Esophagus                               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Gallbladder                             | +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  M  +  +  A  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Colon                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  A  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  M  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Cecum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  A  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Duodenum               | +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  A  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Jejunum                | +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  A  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Ileum                  | +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  A  +|             
                                            __________________________________________________________________________|             
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Angiectasis                          |                                                                          |             
      Eosinophilic Focus                   | X           X                                                  X         |             
      Hematopoietic Cell Proliferation     |                   3                                                      |             
      Inflammation, Chronic                |                                                                          |             
                                            __________________________________________________________________________|             
   Mesentery                               |       +  +              +                                            +   |             
      Inflammation, Chronic                |                                                                          |             
      Fat, Necrosis                        |                         2                                            4   |             
                                            __________________________________________________________________________|             
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  A  +|             
      Atrophy                              |                                                                          |             
      Hyperplasia                          |                            2              1                              |             
      Hypertrophy                          |                      1                                                   |             
      Inflammation                         |                   2                                                      |             
      Duct, Cyst                           |                                                                          |             
                                            __________________________________________________________________________|             
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +|             
      Epithelium, Hyperplasia              |                            1                                             |             
                                            __________________________________________________________________________|             
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +|             
      Erosion                              |                                                                          |             
                                            __________________________________________________________________________|             
   Tooth                                   |                                                                          |             
      Developmental Malformation           |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 CARDIOVASCULAR SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Cardiomyopathy                       | 1     1  1  1     2     1  1  1  1     1     1  1        1        1      |             
      Artery, Inflammation                 |       2                          2                                       |             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM                          |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hematopoietic Cell Proliferation     |                   3                                                      |             
      Hypertrophy                          |       1                                                                  |             
      Capsule, Hyperplasia                 |                                                                          |             
                                            __________________________________________________________________________|             
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hyperplasia                          |                            2                                             |             
                                            __________________________________________________________________________|             
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  A  +|             
                                            __________________________________________________________________________|             
   Parathyroid Gland                       | +  +  +  M  M  +  M  M  +  +  M  +  +  +  +  +  M  +  +  +  M  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
                                                             Page  18                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 5| 7| 7| 7| 7| 6| 7| 7| 7| 7| 4| 6| 7| 7| 7| 6| 7| 6| 7| 0| 5| 7| 7| 7|             
                             DAY ON TEST   | 3| 5| 3| 1| 0| 3| 1| 2| 3| 3| 3| 2| 7| 3| 3| 3| 3| 3| 7| 3| 0| 6| 3| 0| 3|             
                                           | 7| 5| 4| 5| 6| 7| 0| 1| 7| 7| 4| 9| 4| 3| 7| 7| 9| 7| 0| 4| 2| 6| 3| 6| 7|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   B6C3F1 MICE FEMALE                      | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5|             
    600 PPM                                | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
                                           | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM - cont                   |                                                                          |             
                                           |                                                                          |             
      Cyst                                 |                                     2                                    |             
                                            __________________________________________________________________________|             
   Pituitary Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  I  +|             
      Pars Distalis, Hyperplasia           |          2  3  2     2  3     2           1  1     2                     |             
                                            __________________________________________________________________________|             
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +|             
      Follicular Cell, Hyperplasia         | 2                                      2                          2      |             
 _____________________________________________________________________________________________________________________|             
 GENERAL BODY SYSTEM                       |                                                                          |             
                                           |                                                                          |             
    None                                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 GENITAL SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Clitoral Gland                          | +  +  +  M  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  M  M  +  +  +  +|             
                                            __________________________________________________________________________|             
   Ovary                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Atrophy                              |                      2                          2                 4      |             
      Cyst                                 | 2  4                 1  2                       1  4  1              4   |             
      Inflammation                         |                   4                                                      |             
      Pigmentation, Hemosiderin            |                               4                                          |             
      Artery, Inflammation                 |                                                          3               |             
      Corpus Luteum, Hyperplasia           |                                                                          |             
                                            __________________________________________________________________________|             
   Uterus                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +|             
      Angiectasis                          |          3                                                               |             
      Hyperplasia, Cystic                  | 2  2  2  2  2  1  1  2  1  2  2  1     1  2  1  1  2  3        2  1  2  2|             
      Serosa, Cyst                         | 2                                                                        |             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +|             
      Hyperplasia                          |          2        3                                                      |             
                                            __________________________________________________________________________|             
   Lymph Node                              |                   +                 +                                    |             
      Iliac, Hyperplasia                   |                                                                          |             
      Renal, Hyperplasia                   |                   3                                                      |             
                                            __________________________________________________________________________|             
   Lymph Node, Bronchial                   | +  +  +  M  +  +  M  +  +  M  +  +  +  +  +  +  M  +  M  +  +  +  +  M  +|             
      Hyperplasia                          | 2                                2                                       |             
                                            __________________________________________________________________________|             
   Lymph Node, Mandibular                  | +  +  M  +  +  M  M  +  +  +  +  +  +  M  +  +  +  M  +  +  M  +  +  +  M|             
      Hyperplasia                          |                                  2           2                           |             
                                            __________________________________________________________________________|             
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  A  +|             
      Angiectasis                          |                                                                          |             
      Hyperplasia                          |                   2                    2        2                        |             
                                            __________________________________________________________________________|             
   Lymph Node, Mediastinal                 | +  M  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M|             
      Hyperplasia                          |                   2        2                 2                           |             
                                            __________________________________________________________________________|             
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +|             
      Hematopoietic Cell Proliferation     |       2  2        3  2                                         2         |             
      Hyperplasia, Lymphoid                |                                                                          |             
                                            __________________________________________________________________________|             
   Thymus                                  | +  M  +  +  M  +  +  I  +  M  M  +  +  +  +  +  +  +  M  +  +  +  +  M  +|             
      Atrophy                              |                                                 3                        |             
      Hyperplasia, Lymphoid                |                                              2                           |             
 _____________________________________________________________________________________________________________________|             
                                                             Page  19                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 5| 7| 7| 7| 7| 6| 7| 7| 7| 7| 4| 6| 7| 7| 7| 6| 7| 6| 7| 0| 5| 7| 7| 7|             
                             DAY ON TEST   | 3| 5| 3| 1| 0| 3| 1| 2| 3| 3| 3| 2| 7| 3| 3| 3| 3| 3| 7| 3| 0| 6| 3| 0| 3|             
                                           | 7| 5| 4| 5| 6| 7| 0| 1| 7| 7| 4| 9| 4| 3| 7| 7| 9| 7| 0| 4| 2| 6| 3| 6| 7|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   B6C3F1 MICE FEMALE                      | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5|             
    600 PPM                                | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
                                           | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM - cont               |                                                                          |             
                                           |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 INTEGUMENTARY SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Mammary Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Epidermis, Hyperplasia               |                      2                                                   |             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM                    |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Fibrous Osteodystrophy               | 1     2  1                 1  2        2  1  1     1              2      |             
      Cranium, Fracture                    |                                                             X            |             
 _____________________________________________________________________________________________________________________|             
 NERVOUS SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hemorrhage                           |                                                             3            |             
      Hydrocephalus                        |                                                                   2      |             
      Meninges, Infiltration Cellular,     |                                                                          |             
           Mononuclear Cell                |                                                                          |             
                                            __________________________________________________________________________|             
   Spinal Cord                             |                                                                          |             
      Degeneration                         |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 RESPIRATORY SYSTEM                        |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +|             
                                            __________________________________________________________________________|             
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Infiltration Cellular, Histiocyte    | 4                                                                        |             
      Inflammation, Chronic, Focal         | 2                                            2                           |             
      Alveolar Epithelium, Hyperplasia     |       3                                                  4               |             
      Mediastinum, Inflammation            |                2                                                         |             
      Perivascular, Infiltration Cellular, |                                                                          |             
           Mononuclear Cell                |                                              3                           |             
                                            __________________________________________________________________________|             
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  A  +|             
      Inflammation, Suppurative            |             1                                   1                        |             
      Nasolacrimal Duct, Inflammation,     |                                                                          |             
           Suppurative                     |                                                                          |             
      Olfactory Epithelium, Atrophy, Focal |                                                                          |             
                                            __________________________________________________________________________|             
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 SPECIAL SENSES SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Harderian Gland                         |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +|             
      Hydronephrosis                       |          2                                                               |             
      Metaplasia, Osseous                  |                                                       1                  |             
      Nephropathy                          | 1        2     1  1  1  1  1                    2  2     1        1     1|             
 _____________________________________________________________________________________________________________________|             
                                                             Page  20                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 5| 7| 7| 7| 7| 6| 7| 7| 7| 7| 4| 6| 7| 7| 7| 6| 7| 6| 7| 0| 5| 7| 7| 7|             
                             DAY ON TEST   | 3| 5| 3| 1| 0| 3| 1| 2| 3| 3| 3| 2| 7| 3| 3| 3| 3| 3| 7| 3| 0| 6| 3| 0| 3|             
                                           | 7| 5| 4| 5| 6| 7| 0| 1| 7| 7| 4| 9| 4| 3| 7| 7| 9| 7| 0| 4| 2| 6| 3| 6| 7|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   B6C3F1 MICE FEMALE                      | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5|             
    600 PPM                                | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
                                           | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM - cont                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Urinary Bladder                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  A  +|             
 _____________________________________________________________________________________________________________________|             
                                                             Page  21                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 5| 5| 6| 7| 7| 7| 6| 5| 7| 7| 7| 4| 7| 7| 5| 7| 7| 5| 7| 7| 6| 7| 4| 7| 7|            |
                             DAY ON TEST   | 7| 9| 9| 3| 0| 3| 3| 4| 3| 3| 3| 6| 3| 3| 3| 3| 3| 9| 3| 3| 8| 3| 6| 2| 3|            |
                                           | 4| 9| 0| 3| 8| 4| 1| 4| 6| 7| 3| 9| 4| 6| 6| 6| 7| 4| 7| 3| 0| 4| 0| 0| 4|      T (*) |
 _____________________________________________________________________________________________________________________|            |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      O     |
   B6C3F1 MICE FEMALE                      | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      T     |
                               ANIMAL ID   | 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5|      A     |
    600 PPM                                | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|      L     |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 ALIMENTARY SYSTEM                         |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Esophagus                               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Gallbladder                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +|  45        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Colon                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +|  47        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +|  47        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Cecum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +|  47        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Duodenum               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +|  46        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Jejunum                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +|  46        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Ileum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +|  46        |
                                            __________________________________________________________________________|____________|
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Angiectasis                          |                         3                                                |      1  3.0|
      Eosinophilic Focus                   |             X           3                    X                 X         |      7  3.0|
      Hematopoietic Cell Proliferation     | 2                                                                        |      2  2.5|
      Inflammation, Chronic                |                         2                                                |      1  2.0|
                                            __________________________________________________________________________|____________|
   Mesentery                               |                   +     +        +     +        +                        |   9        |
      Inflammation, Chronic                |                         4                                                |      1  4.0|
      Fat, Necrosis                        |                                  4     4                                 |      4  3.5|
                                            __________________________________________________________________________|____________|
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
      Atrophy                              |       2                                                                  |      1  2.0|
      Hyperplasia                          |                                                                          |      2  1.5|
      Hypertrophy                          |                                                                          |      1  1.0|
      Inflammation                         |                                                                          |      1  2.0|
      Duct, Cyst                           |       3                                                                  |      1  3.0|
                                            __________________________________________________________________________|____________|
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Epithelium, Hyperplasia              |                                                                          |      1  1.0|
                                            __________________________________________________________________________|____________|
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +|  48        |
      Erosion                              |                                                                   4      |      1  4.0|
                                            __________________________________________________________________________|____________|
   Tooth                                   |                                                    +                     |   1        |
      Developmental Malformation           |                                                    X                     |      1     |
 _____________________________________________________________________________________________________________________|            |
 CARDIOVASCULAR SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Cardiomyopathy                       | 1     1  1  1     1  1  1  1  1              1                 1         |     25  1.0|
      Artery, Inflammation                 |                                                                          |      2  2.0|
 _____________________________________________________________________________________________________________________|            |
 ENDOCRINE SYSTEM                          |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hematopoietic Cell Proliferation     |                                                                          |      1  3.0|
      Hypertrophy                          |          1                    1                       1  1               |      5  1.0|
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  22                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 5| 5| 6| 7| 7| 7| 6| 5| 7| 7| 7| 4| 7| 7| 5| 7| 7| 5| 7| 7| 6| 7| 4| 7| 7|            |
                             DAY ON TEST   | 7| 9| 9| 3| 0| 3| 3| 4| 3| 3| 3| 6| 3| 3| 3| 3| 3| 9| 3| 3| 8| 3| 6| 2| 3|            |
                                           | 4| 9| 0| 3| 8| 4| 1| 4| 6| 7| 3| 9| 4| 6| 6| 6| 7| 4| 7| 3| 0| 4| 0| 0| 4|      T (*) |
 _____________________________________________________________________________________________________________________|            |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      O     |
   B6C3F1 MICE FEMALE                      | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      T     |
                               ANIMAL ID   | 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5|      A     |
    600 PPM                                | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|      L     |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 ENDOCRINE SYSTEM - cont                   |                                                                          |            |
                                           |                                                                          |            |
      Capsule, Hyperplasia                 |                                                                         4|      1  4.0|
                                            __________________________________________________________________________|____________|
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hyperplasia                          |                                                                          |      1  2.0|
                                            __________________________________________________________________________|____________|
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +|  47        |
                                            __________________________________________________________________________|____________|
   Parathyroid Gland                       | M  M  M  +  +  M  M  +  +  I  M  +  +  M  +  +  +  +  +  M  +  +  +  M  +|  33        |
      Cyst                                 |                                                                          |      1  2.0|
                                            __________________________________________________________________________|____________|
   Pituitary Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
      Pars Distalis, Hyperplasia           |          3     1  3     4              2                 2     4         |     16  2.3|
                                            __________________________________________________________________________|____________|
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Follicular Cell, Hyperplasia         |             1  2           1  1     1  1  1  2  1     4  1     1         |     15  1.5|
 _____________________________________________________________________________________________________________________|            |
 GENERAL BODY SYSTEM                       |                                                                          |            |
                                           |                                                                          |            |
    None                                   |                                                                          |            |
 _____________________________________________________________________________________________________________________|            |
 GENITAL SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Clitoral Gland                          | +  +  +  +  M  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +|  43        |
                                            __________________________________________________________________________|____________|
   Ovary                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Atrophy                              | 2  2        4                                      1           1     3   |      9  2.3|
      Cyst                                 |          2              2                    2           1        1  3   |     14  2.1|
      Inflammation                         |                                                                          |      1  4.0|
      Pigmentation, Hemosiderin            |                                                                          |      1  4.0|
      Artery, Inflammation                 |                                                                          |      1  3.0|
      Corpus Luteum, Hyperplasia           |       4                                                                  |      1  4.0|
                                            __________________________________________________________________________|____________|
   Uterus                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Angiectasis                          |                                                                          |      1  3.0|
      Hyperplasia, Cystic                  | 1     3  1  2  1  2     3  2  1  1  1  2  1  1  1  2  1  1  2  4  1  1   |     44  1.6|
      Serosa, Cyst                         |                                                                          |      1  2.0|
 _____________________________________________________________________________________________________________________|            |
 HEMATOPOIETIC SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Hyperplasia                          | 2                 2                                                      |      4  2.3|
                                            __________________________________________________________________________|____________|
   Lymph Node                              |                   +     +                                                |   4        |
      Iliac, Hyperplasia                   |                         2                                                |      1  2.0|
      Renal, Hyperplasia                   |                                                                          |      1  3.0|
                                            __________________________________________________________________________|____________|
   Lymph Node, Bronchial                   | +  I  +  +  +  +  +  +  +  M  +  M  +  +  +  +  +  +  M  +  M  +  +  +  +|  39        |
      Hyperplasia                          |             2           3                       2                       2|      6  2.2|
                                            __________________________________________________________________________|____________|
   Lymph Node, Mandibular                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  M  +  M  +  I|  39        |
      Hyperplasia                          |                         2                             2                  |      4  2.0|
                                            __________________________________________________________________________|____________|
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  I  +  +  +  +|  47        |
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  23                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 5| 5| 6| 7| 7| 7| 6| 5| 7| 7| 7| 4| 7| 7| 5| 7| 7| 5| 7| 7| 6| 7| 4| 7| 7|            |
                             DAY ON TEST   | 7| 9| 9| 3| 0| 3| 3| 4| 3| 3| 3| 6| 3| 3| 3| 3| 3| 9| 3| 3| 8| 3| 6| 2| 3|            |
                                           | 4| 9| 0| 3| 8| 4| 1| 4| 6| 7| 3| 9| 4| 6| 6| 6| 7| 4| 7| 3| 0| 4| 0| 0| 4|      T (*) |
 _____________________________________________________________________________________________________________________|            |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      O     |
   B6C3F1 MICE FEMALE                      | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      T     |
                               ANIMAL ID   | 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5|      A     |
    600 PPM                                | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|      L     |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 HEMATOPOIETIC SYSTEM - cont               |                                                                          |            |
                                           |                                                                          |            |
      Angiectasis                          |                               1                                          |      1  1.0|
      Hyperplasia                          |                         2                                               2|      5  2.0|
                                            __________________________________________________________________________|____________|
   Lymph Node, Mediastinal                 | M  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  M  M  +  +  +  M  M  +  +|  41        |
      Hyperplasia                          |             2                                                            |      4  2.0|
                                            __________________________________________________________________________|____________|
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Hematopoietic Cell Proliferation     | 3                    2        2                    2                 2   |     10  2.2|
      Hyperplasia, Lymphoid                |             2           2                                                |      2  2.0|
                                            __________________________________________________________________________|____________|
   Thymus                                  | M  +  +  +  +  +  M  +  +  +  +  M  +  M  +  +  +  +  +  +  +  +  +  +  M|  38        |
      Atrophy                              |    1                                      2                              |      3  2.0|
      Hyperplasia, Lymphoid                |                                                                          |      1  2.0|
 _____________________________________________________________________________________________________________________|            |
 INTEGUMENTARY SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Mammary Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Epidermis, Hyperplasia               |                                                                          |      1  2.0|
 _____________________________________________________________________________________________________________________|            |
 MUSCULOSKELETAL SYSTEM                    |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Fibrous Osteodystrophy               |                1                    1           2     3              2  2|     16  1.6|
      Cranium, Fracture                    |                                                                          |      1     |
 _____________________________________________________________________________________________________________________|            |
 NERVOUS SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hemorrhage                           |                                                                          |      1  3.0|
      Hydrocephalus                        |                                                                          |      1  2.0|
      Meninges, Infiltration Cellular,     |                                                                          |            |
           Mononuclear Cell                |                                              1                           |      1  1.0|
                                            __________________________________________________________________________|____________|
   Spinal Cord                             |                                  +                                       |   1        |
      Degeneration                         |                                  1                                       |      1  1.0|
 _____________________________________________________________________________________________________________________|            |
 RESPIRATORY SYSTEM                        |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Infiltration Cellular, Histiocyte    |                                                                          |      1  4.0|
      Inflammation, Chronic, Focal         |                                                                          |      2  2.0|
      Alveolar Epithelium, Hyperplasia     |                                                                          |      2  3.5|
      Mediastinum, Inflammation            |                                                                          |      1  2.0|
      Perivascular, Infiltration Cellular, |                                                                          |            |
           Mononuclear Cell                |          1              3                                                |      3  2.3|
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  24                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 5| 5| 6| 7| 7| 7| 6| 5| 7| 7| 7| 4| 7| 7| 5| 7| 7| 5| 7| 7| 6| 7| 4| 7| 7|            |
                             DAY ON TEST   | 7| 9| 9| 3| 0| 3| 3| 4| 3| 3| 3| 6| 3| 3| 3| 3| 3| 9| 3| 3| 8| 3| 6| 2| 3|            |
                                           | 4| 9| 0| 3| 8| 4| 1| 4| 6| 7| 3| 9| 4| 6| 6| 6| 7| 4| 7| 3| 0| 4| 0| 0| 4|      T (*) |
 _____________________________________________________________________________________________________________________|            |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      O     |
   B6C3F1 MICE FEMALE                      | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      T     |
                               ANIMAL ID   | 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5|      A     |
    600 PPM                                | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|      L     |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 RESPIRATORY SYSTEM - cont                 |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
      Inflammation, Suppurative            |                                                                          |      2  1.0|
      Nasolacrimal Duct, Inflammation,     |                                                                          |            |
           Suppurative                     |                                                    2                     |      1  2.0|
      Olfactory Epithelium, Atrophy, Focal |                         1                                                |      1  1.0|
                                            __________________________________________________________________________|____________|
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +|  48        |
 _____________________________________________________________________________________________________________________|            |
 SPECIAL SENSES SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Harderian Gland                         |                         +                       +                        |   2        |
 _____________________________________________________________________________________________________________________|            |
 URINARY SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Hydronephrosis                       |                                                                          |      1  2.0|
      Metaplasia, Osseous                  |                                                                   1      |      2  1.0|
      Nephropathy                          |                            1  1              1  1  1     1     1         |     19  1.2|
                                            __________________________________________________________________________|____________|
   Urinary Bladder                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +|  47        |
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  25                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 7| 6| 7| 7| 5| 7| 5| 7| 6| 5| 7| 3| 7| 7| 7| 7| 7| 7| 7| 7| 7| 6| 7| 5|             
                             DAY ON TEST   | 3| 3| 2| 3| 3| 8| 3| 5| 3| 3| 6| 3| 9| 3| 3| 3| 3| 3| 3| 3| 3| 3| 0| 3| 7|             
                                           | 7| 4| 8| 4| 7| 2| 3| 8| 6| 1| 6| 6| 9| 4| 6| 3| 3| 4| 4| 3| 4| 3| 4| 3| 4|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   B6C3F1 MICE FEMALE                      | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7|             
    1800 PPM                               | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
                                           | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 ALIMENTARY SYSTEM                         |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Esophagus                               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Gallbladder                             | +  +  +  +  +  +  +  +  +  +  +  M  A  +  +  +  +  +  +  +  +  +  +  +  +|             
      Inflammation                         |                                                                          |             
                                            __________________________________________________________________________|             
   Intestine Large, Colon                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  M  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Cecum                  | +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Duodenum               | +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Jejunum                | +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Ileum                  | +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +|             
      Diverticulum                         |                                                                          |             
      Ulcer                                |                                                                          |             
                                            __________________________________________________________________________|             
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Basophilic Focus                     |                                                                          |             
      Clear Cell Focus                     |                                           X                              |             
      Eosinophilic Focus                   |       X        X  X     X  X              X  X     X                     |             
      Hematopoietic Cell Proliferation     |    1                       2                                             |             
      Hepatodiaphragmatic Nodule           |                                                                          |             
      Mixed Cell Focus                     |                                                                          |             
      Necrosis                             |       1           1                 2           2                        |             
      Thrombosis                           |                                                                          |             
                                            __________________________________________________________________________|             
   Mesentery                               |                                           +                       +     +|             
      Fat, Hemorrhage                      |                                                                          |             
      Fat, Necrosis                        |                                           3                       3      |             
                                            __________________________________________________________________________|             
   Oral Mucosa                             |                                        +                                 |             
                                            __________________________________________________________________________|             
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +|             
      Atrophy                              |                                                                          |             
      Basophilic Focus                     |                                                                X         |             
      Hyperplasia                          |                               1                                          |             
      Hypertrophy                          |       1                                1                                 |             
                                            __________________________________________________________________________|             
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +|             
      Angiectasis                          |                                                                          |             
      Inflammation                         |                                                                          |             
      Ulcer                                |                                                                          |             
      Epithelium, Hyperplasia              |                                                                          |             
                                            __________________________________________________________________________|             
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +|             
      Erosion                              |                                                                          |             
      Epithelium, Hyperplasia              |                                  1                                       |             
 _____________________________________________________________________________________________________________________|             
 CARDIOVASCULAR SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Blood Vessel                            |                +                                                         |             
      Inflammation                         |                2                                                         |             
                                            __________________________________________________________________________|             
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Cardiomyopathy                       |    1  2  1              1  1     1     1  1     1  1  1  1     1     1  1|             
 _____________________________________________________________________________________________________________________|             
                                                             Page  26                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 7| 6| 7| 7| 5| 7| 5| 7| 6| 5| 7| 3| 7| 7| 7| 7| 7| 7| 7| 7| 7| 6| 7| 5|             
                             DAY ON TEST   | 3| 3| 2| 3| 3| 8| 3| 5| 3| 3| 6| 3| 9| 3| 3| 3| 3| 3| 3| 3| 3| 3| 0| 3| 7|             
                                           | 7| 4| 8| 4| 7| 2| 3| 8| 6| 1| 6| 6| 9| 4| 6| 3| 3| 4| 4| 3| 4| 3| 4| 3| 4|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   B6C3F1 MICE FEMALE                      | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7|             
    1800 PPM                               | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
                                           | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 CARDIOVASCULAR SYSTEM - cont              |                                                                          |             
                                           |                                                                          |             
      Mineralization                       |                                                                          |             
      Artery, Inflammation                 |                2                                                         |             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM                          |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hematopoietic Cell Proliferation     |                                                                          |             
      Hypertrophy                          |          1                                         1                     |             
      Necrosis                             |                                                                          |             
                                            __________________________________________________________________________|             
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  M  +  +  +  +|             
      Hyperplasia                          |                                                 4                        |             
      Necrosis                             |                                                                          |             
                                            __________________________________________________________________________|             
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hyperplasia                          |                                                                          |             
                                            __________________________________________________________________________|             
   Parathyroid Gland                       | +  +  +  +  +  M  +  +  +  +  +  M  +  M  M  +  M  I  +  +  M  M  +  +  M|             
                                            __________________________________________________________________________|             
   Pituitary Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Pars Distalis, Cyst                  |                                                                          |             
      Pars Distalis, Hyperplasia           |    2  1  3        2  2        2              2                 1  2  1   |             
                                            __________________________________________________________________________|             
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      C-Cell, Hyperplasia                  |                1                                                         |             
      Follicular Cell, Hyperplasia         |    2     3              1                       1     2                  |             
 _____________________________________________________________________________________________________________________|             
 GENERAL BODY SYSTEM                       |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Peritoneum                              |                                                                          |             
      Inflammation, Suppurative            |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 GENITAL SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Clitoral Gland                          | +  M  I  +  +  +  +  +  +  +  +  M  +  M  +  +  +  +  +  +  +  +  +  +  I|             
                                            __________________________________________________________________________|             
   Ovary                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Angiectasis                          |                                              2                           |             
      Atrophy                              |                   2                    3  2  2     2              3      |             
      Cyst                                 | 2  2  1     3              2              1     2              1  2  2   |             
      Interstitial Cell, Hyperplasia       |                                                                          |             
                                            __________________________________________________________________________|             
   Uterus                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Adenomyosis                          |                      1                                                   |             
      Angiectasis                          |                      2                       2                           |             
      Hydrometra                           |    4                             4     2     4                          3|             
      Hyperplasia, Cystic                  | 4  2  2  2     2  2  2     2  1  1  1     2     1  2  1     2  2  1  2   |             
      Inflammation, Suppurative            |    2                                                                     |             
      Thrombosis                           |                                                                3         |             
      Endometrium, Hyperplasia             |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hyperplasia                          |    2                                                                     |             
 _____________________________________________________________________________________________________________________|             
                                                             Page  27                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 7| 6| 7| 7| 5| 7| 5| 7| 6| 5| 7| 3| 7| 7| 7| 7| 7| 7| 7| 7| 7| 6| 7| 5|             
                             DAY ON TEST   | 3| 3| 2| 3| 3| 8| 3| 5| 3| 3| 6| 3| 9| 3| 3| 3| 3| 3| 3| 3| 3| 3| 0| 3| 7|             
                                           | 7| 4| 8| 4| 7| 2| 3| 8| 6| 1| 6| 6| 9| 4| 6| 3| 3| 4| 4| 3| 4| 3| 4| 3| 4|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   B6C3F1 MICE FEMALE                      | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7|             
    1800 PPM                               | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
                                           | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM - cont               |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Lymph Node                              |                                                                          |             
      Lumbar, Angiectasis                  |                                                                          |             
                                            __________________________________________________________________________|             
   Lymph Node, Bronchial                   | +  +  +  +  +  M  +  +  +  M  +  +  +  +  +  +  +  +  +  +  M  M  +  +  +|             
      Hyperplasia                          |                                        2                                 |             
                                            __________________________________________________________________________|             
   Lymph Node, Mandibular                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  M  +  +  M  M  +  +|             
      Hyperplasia                          |                2                       3                                 |             
      Pigmentation, Hemosiderin            |                                                                          |             
                                            __________________________________________________________________________|             
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hyperplasia                          |                                        3                                 |             
                                            __________________________________________________________________________|             
   Lymph Node, Mediastinal                 | +  +  +  M  +  +  +  +  +  M  M  +  M  +  +  +  +  M  +  +  +  +  +  +  +|             
      Hematopoietic Cell Proliferation     |                                                                          |             
      Hyperplasia                          |                                                                          |             
                                            __________________________________________________________________________|             
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hematopoietic Cell Proliferation     |    2     2           2     2  2  2                                      2|             
      Hyperplasia, Lymphoid                |                                        2                                 |             
                                            __________________________________________________________________________|             
   Thymus                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Angiectasis                          |                                                                          |             
      Atrophy                              |                                                                         4|             
      Hyperplasia, Lymphoid                |                                  2                                       |             
 _____________________________________________________________________________________________________________________|             
 INTEGUMENTARY SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Mammary Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Subcutaneous Tissue, Angiectasis     |                                              2                           |             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM                    |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Arthrosis                            |       3        2                                                         |             
      Fibrous Osteodystrophy               | 3           2              1  3     1     2        2  2  1           3   |             
 _____________________________________________________________________________________________________________________|             
 NERVOUS SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Meninges, Infiltration Cellular,     |                                                                          |             
           Mononuclear Cell                |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 RESPIRATORY SYSTEM                        |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Infiltration Cellular, Histiocyte    |                                                                1        3|             
      Alveolar Epithelium, Hyperplasia     |                                                                1         |             
                                            __________________________________________________________________________|             
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 SPECIAL SENSES SYSTEM                     |                                                                          |             
                                           |                                                                          |             
 _____________________________________________________________________________________________________________________|             
                                                             Page  28                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 7| 6| 7| 7| 5| 7| 5| 7| 6| 5| 7| 3| 7| 7| 7| 7| 7| 7| 7| 7| 7| 6| 7| 5|             
                             DAY ON TEST   | 3| 3| 2| 3| 3| 8| 3| 5| 3| 3| 6| 3| 9| 3| 3| 3| 3| 3| 3| 3| 3| 3| 0| 3| 7|             
                                           | 7| 4| 8| 4| 7| 2| 3| 8| 6| 1| 6| 6| 9| 4| 6| 3| 3| 4| 4| 3| 4| 3| 4| 3| 4|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   B6C3F1 MICE FEMALE                      | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7|             
    1800 PPM                               | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
                                           | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 SPECIAL SENSES SYSTEM - cont              |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Harderian Gland                         |             +                                                            |             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +|             
      Nephropathy                          |          1              1     1  1     1           1     1     1        1|             
                                            __________________________________________________________________________|             
   Urinary Bladder                         | +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
                                                             Page  29                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 7| 4| 7| 7| 7| 6| 6| 7| 7| 7| 7| 5| 7| 7| 7| 7| 5| 7| 5| 5| 6| 7| 7| 5|            |
                             DAY ON TEST   | 0| 3| 0| 3| 3| 3| 1| 6| 3| 3| 3| 3| 9| 3| 3| 3| 3| 2| 3| 6| 7| 4| 3| 3| 9|            |
                                           | 2| 6| 3| 6| 4| 3| 0| 4| 7| 3| 7| 7| 9| 6| 3| 3| 6| 7| 3| 2| 7| 5| 6| 4| 8|      T (*) |
 _____________________________________________________________________________________________________________________|            |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      O     |
   B6C3F1 MICE FEMALE                      | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      T     |
                               ANIMAL ID   | 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7|      A     |
    1800 PPM                               | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|      L     |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 ALIMENTARY SYSTEM                         |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Esophagus                               | +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +|  48        |
                                            __________________________________________________________________________|____________|
   Gallbladder                             | +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  M  A|  44        |
      Inflammation                         |                            1                                             |      1  1.0|
                                            __________________________________________________________________________|____________|
   Intestine Large, Colon                  | +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  A|  47        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Rectum                 | +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  A|  45        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Cecum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  A|  47        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Duodenum               | +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  A|  46        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Jejunum                | +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  A|  46        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Ileum                  | +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  A|  46        |
      Diverticulum                         |                                                                X         |      1     |
      Ulcer                                |                                                                4         |      1  4.0|
                                            __________________________________________________________________________|____________|
   Liver                                   | +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +|  48        |
      Basophilic Focus                     |                                                          X               |      1     |
      Clear Cell Focus                     |                                                                          |      1     |
      Eosinophilic Focus                   |                                                 X  X                 X   |     11     |
      Hematopoietic Cell Proliferation     |                                                                2         |      3  1.7|
      Hepatodiaphragmatic Nodule           |                                                                X         |      1     |
      Mixed Cell Focus                     |                                  X                                       |      1     |
      Necrosis                             |                   4                    1                       2         |      7  1.9|
      Thrombosis                           |                   3                                                      |      1  3.0|
                                            __________________________________________________________________________|____________|
   Mesentery                               |       +  +                             +     +              +        +   |   9        |
      Fat, Hemorrhage                      |       4                                                                  |      1  4.0|
      Fat, Necrosis                        |          2                             2     2              3        2   |      7  2.4|
                                            __________________________________________________________________________|____________|
   Oral Mucosa                             |                                                                          |   1        |
                                            __________________________________________________________________________|____________|
   Pancreas                                | +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  A|  46        |
      Atrophy                              |                                  1                                       |      1  1.0|
      Basophilic Focus                     |                                                                          |      1     |
      Hyperplasia                          |                                        2                                 |      2  1.5|
      Hypertrophy                          |                                                                          |      2  1.0|
                                            __________________________________________________________________________|____________|
   Salivary Glands                         | +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +|  48        |
                                            __________________________________________________________________________|____________|
   Stomach, Forestomach                    | +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +|  47        |
      Angiectasis                          |                            2                                             |      1  2.0|
      Inflammation                         |                                                                         1|      1  1.0|
      Ulcer                                | 1                 1                                                      |      2  1.0|
      Epithelium, Hyperplasia              |                                                                         1|      1  1.0|
                                            __________________________________________________________________________|____________|
   Stomach, Glandular                      | +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +|  47        |
      Erosion                              |                   1  1                                                   |      2  1.0|
      Epithelium, Hyperplasia              |                                                                          |      1  1.0|
 _____________________________________________________________________________________________________________________|            |
 CARDIOVASCULAR SYSTEM                     |                                                                          |            |
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  30                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 7| 4| 7| 7| 7| 6| 6| 7| 7| 7| 7| 5| 7| 7| 7| 7| 5| 7| 5| 5| 6| 7| 7| 5|            |
                             DAY ON TEST   | 0| 3| 0| 3| 3| 3| 1| 6| 3| 3| 3| 3| 9| 3| 3| 3| 3| 2| 3| 6| 7| 4| 3| 3| 9|            |
                                           | 2| 6| 3| 6| 4| 3| 0| 4| 7| 3| 7| 7| 9| 6| 3| 3| 6| 7| 3| 2| 7| 5| 6| 4| 8|      T (*) |
 _____________________________________________________________________________________________________________________|            |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      O     |
   B6C3F1 MICE FEMALE                      | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      T     |
                               ANIMAL ID   | 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7|      A     |
    1800 PPM                               | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|      L     |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 CARDIOVASCULAR SYSTEM - cont              |                                                                          |            |
                                           |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Blood Vessel                            |                                                                          |   1        |
      Inflammation                         |                                                                          |      1  2.0|
                                            __________________________________________________________________________|____________|
   Heart                                   | +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +|  48        |
      Cardiomyopathy                       |                   1     1  1  1           1                    1     1   |     22  1.0|
      Mineralization                       |                   2                                                      |      1  2.0|
      Artery, Inflammation                 |                                                                          |      1  2.0|
 _____________________________________________________________________________________________________________________|            |
 ENDOCRINE SYSTEM                          |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Adrenal Cortex                          | +  +  M  +  +  +  +  +  +  +  +  +     +  +  +  +  +  +  +  A  +  +  +  A|  46        |
      Hematopoietic Cell Proliferation     |                                                                3         |      1  3.0|
      Hypertrophy                          |                1                                                         |      3  1.0|
      Necrosis                             |                   4                                                      |      1  4.0|
                                            __________________________________________________________________________|____________|
   Adrenal Medulla                         | +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  M|  45        |
      Hyperplasia                          |                                                                          |      1  4.0|
      Necrosis                             |                   4                                                      |      1  4.0|
                                            __________________________________________________________________________|____________|
   Islets, Pancreatic                      | +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  M|  46        |
      Hyperplasia                          | 1                                                                        |      1  1.0|
                                            __________________________________________________________________________|____________|
   Parathyroid Gland                       | +  +  A  M  M  +  +  +  +  M  M  M  +  +  +  +  +  +  +  +  +  +  +  +  A|  34        |
                                            __________________________________________________________________________|____________|
   Pituitary Gland                         | +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +|  48        |
      Pars Distalis, Cyst                  |                                        1                                 |      1  1.0|
      Pars Distalis, Hyperplasia           |          2  2  2  3           1  2     1        1              1     4   |     20  1.9|
                                            __________________________________________________________________________|____________|
   Thyroid Gland                           | +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  A|  47        |
      C-Cell, Hyperplasia                  |                                                                          |      1  1.0|
      Follicular Cell, Hyperplasia         |          1              1     2  1                                1      |     10  1.5|
 _____________________________________________________________________________________________________________________|            |
 GENERAL BODY SYSTEM                       |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Peritoneum                              |                                                                +         |   1        |
      Inflammation, Suppurative            |                                                                3         |      1  3.0|
 _____________________________________________________________________________________________________________________|            |
 GENITAL SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Clitoral Gland                          | +  +  +  +  +  I  M  M  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +|  41        |
                                            __________________________________________________________________________|____________|
   Ovary                                   | +  +  A  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  A  +  M  +  +|  46        |
      Angiectasis                          |                                                                          |      1  2.0|
      Atrophy                              | 3                                      2                             3   |      9  2.4|
      Cyst                                 |    4              3     1  2              4  2                 1         |     17  2.1|
      Interstitial Cell, Hyperplasia       |                                                       3                  |      1  3.0|
                                            __________________________________________________________________________|____________|
   Uterus                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A|  49        |
      Adenomyosis                          |                                                                          |      1  1.0|
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  31                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 7| 4| 7| 7| 7| 6| 6| 7| 7| 7| 7| 5| 7| 7| 7| 7| 5| 7| 5| 5| 6| 7| 7| 5|            |
                             DAY ON TEST   | 0| 3| 0| 3| 3| 3| 1| 6| 3| 3| 3| 3| 9| 3| 3| 3| 3| 2| 3| 6| 7| 4| 3| 3| 9|            |
                                           | 2| 6| 3| 6| 4| 3| 0| 4| 7| 3| 7| 7| 9| 6| 3| 3| 6| 7| 3| 2| 7| 5| 6| 4| 8|      T (*) |
 _____________________________________________________________________________________________________________________|            |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      O     |
   B6C3F1 MICE FEMALE                      | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      T     |
                               ANIMAL ID   | 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7|      A     |
    1800 PPM                               | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|      L     |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 GENITAL SYSTEM - cont                     |                                                                          |            |
                                           |                                                                          |            |
      Angiectasis                          |             2                                                            |      3  2.0|
      Hydrometra                           |                2           4        3           3        4        2      |     11  3.2|
      Hyperplasia, Cystic                  | 3  2  1  2  2  2  1  2  2  2  3  2  1  2  2  2  2  3     1     2  1  3   |     41  1.9|
      Inflammation, Suppurative            |                                                                   2      |      2  2.0|
      Thrombosis                           |                                                                          |      1  3.0|
      Endometrium, Hyperplasia             | 2                                                                        |      1  2.0|
 _____________________________________________________________________________________________________________________|            |
 HEMATOPOIETIC SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone Marrow                             | +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  I  A  +  +  +  A|  46        |
      Hyperplasia                          |                                                                3         |      2  2.5|
                                            __________________________________________________________________________|____________|
   Lymph Node                              |    +              +                                                      |   2        |
      Lumbar, Angiectasis                  |    4                                                                     |      1  4.0|
                                            __________________________________________________________________________|____________|
   Lymph Node, Bronchial                   | +  +  A  M  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  M  M|  41        |
      Hyperplasia                          |                                                                   3      |      2  2.5|
                                            __________________________________________________________________________|____________|
   Lymph Node, Mandibular                  | M  +  A  +  +  M  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  M  +  +|  41        |
      Hyperplasia                          |                               2                                          |      3  2.3|
      Pigmentation, Hemosiderin            |             2                                                            |      1  2.0|
                                            __________________________________________________________________________|____________|
   Lymph Node, Mesenteric                  | +  +  A  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  A|  45        |
      Hyperplasia                          |    2                          2                                          |      3  2.3|
                                            __________________________________________________________________________|____________|
   Lymph Node, Mediastinal                 | M  +  M  +  +  +  +  M  +  +  +  +  +  M  +  +  +  +  +  M  M  +  +  +  M|  38        |
      Hematopoietic Cell Proliferation     |                                                                2         |      1  2.0|
      Hyperplasia                          |                                                                   2      |      1  2.0|
                                            __________________________________________________________________________|____________|
   Spleen                                  | +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  A|  46        |
      Hematopoietic Cell Proliferation     |                                                                2         |      8  2.0|
      Hyperplasia, Lymphoid                |                                                                   3      |      2  2.5|
                                            __________________________________________________________________________|____________|
   Thymus                                  | M  +  M  +  +  +  +  M  M  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  M|  44        |
      Angiectasis                          |                                                 2                        |      1  2.0|
      Atrophy                              |                                                    1                     |      2  2.5|
      Hyperplasia, Lymphoid                |    2                                                                     |      2  2.0|
 _____________________________________________________________________________________________________________________|            |
 INTEGUMENTARY SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Mammary Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Subcutaneous Tissue, Angiectasis     |                                                                          |      1  2.0|
 _____________________________________________________________________________________________________________________|            |
 MUSCULOSKELETAL SYSTEM                    |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  I  +  +  +  +  +|  49        |
      Arthrosis                            |                                                                          |      2  2.5|
      Fibrous Osteodystrophy               | 1                                1        1  1                       1   |     15  1.7|
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  32                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 7| 4| 7| 7| 7| 6| 6| 7| 7| 7| 7| 5| 7| 7| 7| 7| 5| 7| 5| 5| 6| 7| 7| 5|            |
                             DAY ON TEST   | 0| 3| 0| 3| 3| 3| 1| 6| 3| 3| 3| 3| 9| 3| 3| 3| 3| 2| 3| 6| 7| 4| 3| 3| 9|            |
                                           | 2| 6| 3| 6| 4| 3| 0| 4| 7| 3| 7| 7| 9| 6| 3| 3| 6| 7| 3| 2| 7| 5| 6| 4| 8|      T (*) |
 _____________________________________________________________________________________________________________________|            |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      O     |
   B6C3F1 MICE FEMALE                      | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      T     |
                               ANIMAL ID   | 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7|      A     |
    1800 PPM                               | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|      L     |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 MUSCULOSKELETAL SYSTEM - cont             |                                                                          |            |
                                           |                                                                          |            |
 _____________________________________________________________________________________________________________________|            |
 NERVOUS SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Brain                                   | +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Meninges, Infiltration Cellular,     |                                                                          |            |
           Mononuclear Cell                |             2                             1              1               |      3  1.3|
 _____________________________________________________________________________________________________________________|            |
 RESPIRATORY SYSTEM                        |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Larynx                                  | +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  A|  46        |
                                            __________________________________________________________________________|____________|
   Lung                                    | +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Infiltration Cellular, Histiocyte    |                                                                          |      2  2.0|
      Alveolar Epithelium, Hyperplasia     |                                                                          |      1  1.0|
                                            __________________________________________________________________________|____________|
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A|  49        |
                                            __________________________________________________________________________|____________|
   Trachea                                 | +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  A|  46        |
 _____________________________________________________________________________________________________________________|            |
 SPECIAL SENSES SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Harderian Gland                         |                                                                          |   1        |
 _____________________________________________________________________________________________________________________|            |
 URINARY SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Kidney                                  | +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  A|  46        |
      Nephropathy                          |          1                                1              3           1   |     13  1.2|
                                            __________________________________________________________________________|____________|
   Urinary Bladder                         | +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  M  +  A|  45        |
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  33                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 6| 7| 7| 7| 7| 7| 7| 5| 7| 7| 7| 7| 4| 6| 7| 7| 7| 7| 5| 6| 6| 6| 3| 7| 7|             
                             DAY ON TEST   | 7| 3| 3| 3| 1| 3| 3| 4| 3| 3| 3| 3| 4| 7| 3| 3| 3| 3| 8| 3| 7| 5| 6| 3| 3|             
                                           | 0| 4| 6| 4| 9| 3| 7| 4| 4| 6| 7| 4| 0| 5| 6| 4| 6| 6| 2| 8| 8| 8| 2| 7| 3|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   B6C3F1 MICE MALE                        | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
    CONTROL                                | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
                                           | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 ALIMENTARY SYSTEM                         |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Esophagus                               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
                                            __________________________________________________________________________|             
   Gallbladder                             | +  +  +  +  A  +  M  +  +  +  +  +  A  +  +  +  +  +  +  M  +  +  A  M  +|             
      Degeneration, Hyaline                |                                                                          |             
      Inflammation                         |                                                                          |             
      Epithelium, Hyperplasia              |                                                       1                  |             
                                            __________________________________________________________________________|             
   Intestine Large, Colon                  | +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  A  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  M  +  +  +  +  +  A  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Cecum                  | +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  A  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Duodenum               | A  +  +  +  A  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  A  +  +|             
      Epithelium, Hyperplasia              |       3                                                                  |             
                                            __________________________________________________________________________|             
   Intestine Small, Jejunum                | +  +  +  +  A  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  A  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Ileum                  | +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  A  +  +|             
                                            __________________________________________________________________________|             
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Basophilic Focus                     |             X                                                            |             
      Congestion                           |                                                                          |             
      Degeneration, Fatty, Focal           |                                                                          |             
      Eosinophilic Focus                   |       X                 X  X  X  X        X                       X      |             
      Infiltration Cellular, Histiocyte    |                                        2                                 |             
      Inflammation, Chronic                |                                                                          |             
      Mixed Cell Focus                     |                                  X                                       |             
      Necrosis                             |                                     3                             3      |             
                                            __________________________________________________________________________|             
   Mesentery                               |                               +              +                           |             
      Fat, Necrosis                        |                               2                                          |             
                                            __________________________________________________________________________|             
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  M  +  +|             
      Amyloid Deposition                   |                                                                          |             
      Atrophy                              |                                                                          |             
      Cytoplasmic Alteration               |                                                                          |             
                                            __________________________________________________________________________|             
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +|             
      Ulcer                                |                                                                          |             
      Epithelium, Hyperplasia              |                                           1                              |             
                                            __________________________________________________________________________|             
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  A  +  +|             
      Mineralization                       |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 CARDIOVASCULAR SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
      Cardiomyopathy                       |    1  1        1        1        1           2  1  1     1     1         |             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM                          |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  A  +  +|             
      Hyperplasia                          |                                                       3  1           4   |             
      Hypertrophy                          | 1  1  1                    1  2                 3                    1  1|             
                                            __________________________________________________________________________|             
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  A  +  +|             
                                            __________________________________________________________________________|             
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  M  +  +|             
 _____________________________________________________________________________________________________________________|             
                                                             Page  34                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 6| 7| 7| 7| 7| 7| 7| 5| 7| 7| 7| 7| 4| 6| 7| 7| 7| 7| 5| 6| 6| 6| 3| 7| 7|             
                             DAY ON TEST   | 7| 3| 3| 3| 1| 3| 3| 4| 3| 3| 3| 3| 4| 7| 3| 3| 3| 3| 8| 3| 7| 5| 6| 3| 3|             
                                           | 0| 4| 6| 4| 9| 3| 7| 4| 4| 6| 7| 4| 0| 5| 6| 4| 6| 6| 2| 8| 8| 8| 2| 7| 3|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   B6C3F1 MICE MALE                        | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
    CONTROL                                | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
                                           | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM - cont                   |                                                                          |             
                                           |                                                                          |             
      Hyperplasia                          |                                                                      2   |             
                                            __________________________________________________________________________|             
   Parathyroid Gland                       | +  +  +  +  +  +  +  +  +  +  +  +  M  +  M  +  +  M  +  +  +  +  M  M  +|             
                                            __________________________________________________________________________|             
   Pituitary Gland                         | +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
      Pars Distalis, Cyst                  |    2                                         1                           |             
      Pars Distalis, Hyperplasia           |                                  1                 1                     |             
                                            __________________________________________________________________________|             
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
      Follicular Cell, Hyperplasia         |       1                          1     1  1  3  1  2           1         |             
 _____________________________________________________________________________________________________________________|             
 GENERAL BODY SYSTEM                       |                                                                          |             
                                           |                                                                          |             
    None                                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 GENITAL SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Epididymis                              | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
                                            __________________________________________________________________________|             
   Penis                                   |                                                                   +      |             
                                            __________________________________________________________________________|             
   Preputial Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Cyst                                 | 3                             2                                          |             
      Inflammation                         |    2                    4        2        4                          4   |             
                                            __________________________________________________________________________|             
   Prostate                                | +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  A  +  +|             
      Inflammation, Suppurative            |                                                          2  1            |             
                                            __________________________________________________________________________|             
   Seminal Vesicle                         | +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  A  +  +|             
                                            __________________________________________________________________________|             
   Testes                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Atrophy                              |                   1                                3     1               |             
      Interstitial Cell, Hyperplasia       |                   1                                                      |             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
      Angiectasis                          |                                                                         2|             
      Hyperplasia                          |                                                          2               |             
                                            __________________________________________________________________________|             
   Lymph Node                              |                                                          +               |             
      Renal, Hyperplasia                   |                                                          3               |             
                                            __________________________________________________________________________|             
   Lymph Node, Bronchial                   | +  M  +  +  +  +  M  M  M  +  +  +  +  +  +  M  +  M  +  M  +  +  A  +  +|             
      Hyperplasia                          |                            2                                             |             
                                            __________________________________________________________________________|             
   Lymph Node, Mandibular                  | +  +  M  +  M  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +|             
      Hyperplasia                          |                            2                          2                  |             
                                            __________________________________________________________________________|             
   Lymph Node, Mesenteric                  | +  +  +  +  M  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  A  +  +|             
      Angiectasis                          |                                                                          |             
      Hematopoietic Cell Proliferation     |                                                          2               |             
      Hyperplasia                          |                                                                          |             
                                            __________________________________________________________________________|             
   Lymph Node, Mediastinal                 | +  +  +  +  M  +  +  M  +  +  M  +  M  +  M  +  M  M  +  M  +  +  M  +  +|             
                                            __________________________________________________________________________|             
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  M  +  +|             
      Hematopoietic Cell Proliferation     |          1           2                 2     2        2  2     2         |             
      Hyperplasia, Lymphoid                |                            2                                             |             
                                            __________________________________________________________________________|             
   Thymus                                  | M  +  +  +  M  +  +  +  +  +  +  +  +  M  +  M  +  +  +  M  +  M  A  +  +|             
      Atrophy                              |                                                                          |             
 _____________________________________________________________________________________________________________________|             
                                                             Page  35                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 6| 7| 7| 7| 7| 7| 7| 5| 7| 7| 7| 7| 4| 6| 7| 7| 7| 7| 5| 6| 6| 6| 3| 7| 7|             
                             DAY ON TEST   | 7| 3| 3| 3| 1| 3| 3| 4| 3| 3| 3| 3| 4| 7| 3| 3| 3| 3| 8| 3| 7| 5| 6| 3| 3|             
                                           | 0| 4| 6| 4| 9| 3| 7| 4| 4| 6| 7| 4| 0| 5| 6| 4| 6| 6| 2| 8| 8| 8| 2| 7| 3|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   B6C3F1 MICE MALE                        | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
    CONTROL                                | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
                                           | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM - cont               |                                                                          |             
                                           |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 INTEGUMENTARY SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Mammary Gland                           | M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M|             
                                            __________________________________________________________________________|             
   Skin                                    | M  +  +  +  +  +  +  +  +  +  +  +  I  +  +  +  +  +  M  +  +  +  +  +  +|             
      Prepuce, Inflammation, Suppurative   |                                  3                 4     4  4  2         |             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM                    |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Fibrous Osteodystrophy               |                   2                       2                              |             
                                            __________________________________________________________________________|             
   Skeletal Muscle                         |                                        +     +                           |             
 _____________________________________________________________________________________________________________________|             
 NERVOUS SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 RESPIRATORY SYSTEM                        |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  A  +  +|             
                                            __________________________________________________________________________|             
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Infiltration Cellular, Histiocyte    |       2                       2                                          |             
      Alveolar Epithelium, Hyperplasia     | 1                                2                                       |             
                                            __________________________________________________________________________|             
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  A  +  +|             
      Nasolacrimal Duct, Inflammation,     |                                                                          |             
           Suppurative                     |                                                       1                  |             
      Olfactory Epithelium, Atrophy, Focal |                   1                                                      |             
                                            __________________________________________________________________________|             
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  A  +  +|             
 _____________________________________________________________________________________________________________________|             
 SPECIAL SENSES SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Harderian Gland                         |                                                       +        +         |             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +|             
      Glomerulosclerosis                   |                                                                2         |             
      Hydronephrosis                       |                                                                2         |             
      Inflammation, Suppurative            |                                                          2  1            |             
      Nephropathy                          | 1  1        1     1        1  1  1        1     1  1  1              1  1|             
      Cortex, Cyst                         |                                                                          |             
      Renal Tubule, Hyperplasia            |                            2                                             |             
                                            __________________________________________________________________________|             
   Urinary Bladder                         | +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  A  +  +|             
      Inflammation, Suppurative            |                                                          3  4            |             
 _____________________________________________________________________________________________________________________|             
                                                             Page  36                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 7| 7| 6| 7| 7| 7| 7| 7| 4| 7| 6| 5| 7| 6| 6| 7| 7| 5| 7| 7| 7| 7| 7| 7|            |
                             DAY ON TEST   | 2| 3| 3| 9| 3| 3| 3| 3| 3| 8| 3| 4| 5| 3| 3| 9| 3| 3| 8| 3| 3| 3| 3| 3| 3|            |
                                           | 1| 3| 7| 0| 4| 6| 3| 3| 4| 1| 4| 4| 7| 3| 8| 9| 3| 3| 2| 6| 6| 6| 4| 3| 3|      T (*) |
 _____________________________________________________________________________________________________________________|            |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      O     |
   B6C3F1 MICE MALE                        | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      T     |
                               ANIMAL ID   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      A     |
    CONTROL                                | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|      L     |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 ALIMENTARY SYSTEM                         |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Esophagus                               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Gallbladder                             | +  +  +  +  +  +  +  +  +  A  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +|  42        |
      Degeneration, Hyaline                |                                        2                                 |      1  2.0|
      Inflammation                         |                1                                                         |      1  1.0|
      Epithelium, Hyperplasia              |                                                                          |      1  1.0|
                                            __________________________________________________________________________|____________|
   Intestine Large, Colon                  | +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  47        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Rectum                 | +  M  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +|  44        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Cecum                  | +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  47        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Duodenum               | +  +  +  +  +  +  +  +  +  A  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +|  44        |
      Epithelium, Hyperplasia              |                                                                          |      1  3.0|
                                            __________________________________________________________________________|____________|
   Intestine Small, Jejunum                | +  +  +  +  +  +  +  +  +  A  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +|  45        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Ileum                  | +  +  +  +  +  +  +  +  +  A  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +|  46        |
                                            __________________________________________________________________________|____________|
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Basophilic Focus                     |                                                                          |      1     |
      Congestion                           |                            3        2                                    |      2  2.5|
      Degeneration, Fatty, Focal           |                   2                                                      |      1  2.0|
      Eosinophilic Focus                   |                X              X                    X                    X|     11     |
      Infiltration Cellular, Histiocyte    |                                                                          |      1  2.0|
      Inflammation, Chronic                |                                  3                                       |      1  3.0|
      Mixed Cell Focus                     |                                                                          |      1     |
      Necrosis                             |                            2     4  1           1     2                 4|      8  2.5|
                                            __________________________________________________________________________|____________|
   Mesentery                               |    +                                                                     |   3        |
      Fat, Necrosis                        |    2                                                                     |      2  2.0|
                                            __________________________________________________________________________|____________|
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
      Amyloid Deposition                   |                                                             1            |      1  1.0|
      Atrophy                              |                                                                1         |      1  1.0|
      Cytoplasmic Alteration               |       1                                                                  |      1  1.0|
                                            __________________________________________________________________________|____________|
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Ulcer                                |                                     1                                    |      1  1.0|
      Epithelium, Hyperplasia              |                                                                          |      1  1.0|
                                            __________________________________________________________________________|____________|
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
      Mineralization                       |                                        1                                 |      1  1.0|
 _____________________________________________________________________________________________________________________|            |
 CARDIOVASCULAR SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Cardiomyopathy                       | 1  1     1  1  1        1     1     1  1  1  1  1     1  1  2  1  2     1|     28  1.1|
 _____________________________________________________________________________________________________________________|            |
 ENDOCRINE SYSTEM                          |                                                                          |            |
                                           |                                                                          |            |
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  37                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 7| 7| 6| 7| 7| 7| 7| 7| 4| 7| 6| 5| 7| 6| 6| 7| 7| 5| 7| 7| 7| 7| 7| 7|            |
                             DAY ON TEST   | 2| 3| 3| 9| 3| 3| 3| 3| 3| 8| 3| 4| 5| 3| 3| 9| 3| 3| 8| 3| 3| 3| 3| 3| 3|            |
                                           | 1| 3| 7| 0| 4| 6| 3| 3| 4| 1| 4| 4| 7| 3| 8| 9| 3| 3| 2| 6| 6| 6| 4| 3| 3|      T (*) |
 _____________________________________________________________________________________________________________________|            |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      O     |
   B6C3F1 MICE MALE                        | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      T     |
                               ANIMAL ID   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      A     |
    CONTROL                                | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|      L     |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 ENDOCRINE SYSTEM - cont                   |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
      Hyperplasia                          |    2              2                                         1  3         |      7  2.3|
      Hypertrophy                          |    2  2     1  1     2  1     1  2     2  2              1     2         |     20  1.5|
                                            __________________________________________________________________________|____________|
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
                                            __________________________________________________________________________|____________|
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
      Hyperplasia                          |    2                 3           1     1                             1   |      6  1.7|
                                            __________________________________________________________________________|____________|
   Parathyroid Gland                       | +  +  M  +  M  +  +  +  +  +  M  +  +  +  +  M  +  +  +  I  +  +  +  M  +|  39        |
                                            __________________________________________________________________________|____________|
   Pituitary Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  I  +  +  +  +  +  M  +  M  +  +  +  +|  45        |
      Pars Distalis, Cyst                  |                         1        1                             1         |      5  1.2|
      Pars Distalis, Hyperplasia           |                                                                          |      2  1.0|
                                            __________________________________________________________________________|____________|
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Follicular Cell, Hyperplasia         | 1     2        2                    1  1     1     2              1      |     16  1.4|
 _____________________________________________________________________________________________________________________|            |
 GENERAL BODY SYSTEM                       |                                                                          |            |
                                           |                                                                          |            |
    None                                   |                                                                          |            |
 _____________________________________________________________________________________________________________________|            |
 GENITAL SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Epididymis                              | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Penis                                   |                                                                          |   1        |
                                            __________________________________________________________________________|____________|
   Preputial Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Cyst                                 |                                  3  2                             2      |      5  2.4|
      Inflammation                         | 3                             2                    3                     |      8  3.0|
                                            __________________________________________________________________________|____________|
   Prostate                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
      Inflammation, Suppurative            |                                  1                                       |      3  1.3|
                                            __________________________________________________________________________|____________|
   Seminal Vesicle                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
                                            __________________________________________________________________________|____________|
   Testes                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Atrophy                              | 2                                4                                       |      5  2.2|
      Interstitial Cell, Hyperplasia       |                                                                          |      1  1.0|
 _____________________________________________________________________________________________________________________|            |
 HEMATOPOIETIC SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Angiectasis                          |                                                                          |      1  2.0|
      Hyperplasia                          |                                  2        2  3        2                  |      5  2.2|
                                            __________________________________________________________________________|____________|
   Lymph Node                              |                                                                          |   1        |
      Renal, Hyperplasia                   |                                                                          |      1  3.0|
                                            __________________________________________________________________________|____________|
   Lymph Node, Bronchial                   | M  M  +  M  M  +  +  +  M  M  +  +  +  +  M  +  +  +  M  +  +  +  M  +  +|  33        |
      Hyperplasia                          |                                                                      2   |      2  2.0|
                                            __________________________________________________________________________|____________|
   Lymph Node, Mandibular                  | M  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  M  +  +  +  M|  42        |
      Hyperplasia                          |                   2                             3                        |      4  2.3|
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  38                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 7| 7| 6| 7| 7| 7| 7| 7| 4| 7| 6| 5| 7| 6| 6| 7| 7| 5| 7| 7| 7| 7| 7| 7|            |
                             DAY ON TEST   | 2| 3| 3| 9| 3| 3| 3| 3| 3| 8| 3| 4| 5| 3| 3| 9| 3| 3| 8| 3| 3| 3| 3| 3| 3|            |
                                           | 1| 3| 7| 0| 4| 6| 3| 3| 4| 1| 4| 4| 7| 3| 8| 9| 3| 3| 2| 6| 6| 6| 4| 3| 3|      T (*) |
 _____________________________________________________________________________________________________________________|            |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      O     |
   B6C3F1 MICE MALE                        | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      T     |
                               ANIMAL ID   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      A     |
    CONTROL                                | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|      L     |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 HEMATOPOIETIC SYSTEM - cont               |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  47        |
      Angiectasis                          | 2                                                           4            |      2  3.0|
      Hematopoietic Cell Proliferation     |                                                             2            |      2  2.0|
      Hyperplasia                          |                3                                2                       2|      3  2.3|
                                            __________________________________________________________________________|____________|
   Lymph Node, Mediastinal                 | +  +  +  +  +  +  +  +  +  +  +  +  M  +  M  +  M  +  M  +  +  +  M  +  +|  36        |
                                            __________________________________________________________________________|____________|
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
      Hematopoietic Cell Proliferation     |                                                       2     2            |      9  1.9|
      Hyperplasia, Lymphoid                |                2  2  2                             2                     |      5  2.0|
                                            __________________________________________________________________________|____________|
   Thymus                                  | M  +  I  +  +  +  +  +  M  +  +  M  +  +  M  +  +  +  +  +  +  +  M  M  M|  35        |
      Atrophy                              |                                              2              4            |      2  3.0|
 _____________________________________________________________________________________________________________________|            |
 INTEGUMENTARY SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Mammary Gland                           | M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M|            |
                                            __________________________________________________________________________|____________|
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  47        |
      Prepuce, Inflammation, Suppurative   |                                           4  4                           |      7  3.6|
 _____________________________________________________________________________________________________________________|            |
 MUSCULOSKELETAL SYSTEM                    |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Fibrous Osteodystrophy               |                                                 1                        |      3  1.7|
                                            __________________________________________________________________________|____________|
   Skeletal Muscle                         |                                                                          |   2        |
 _____________________________________________________________________________________________________________________|            |
 NERVOUS SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 RESPIRATORY SYSTEM                        |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
                                            __________________________________________________________________________|____________|
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Infiltration Cellular, Histiocyte    |                                     3                 2              4   |      5  2.6|
      Alveolar Epithelium, Hyperplasia     |                                                 2  1           2        2|      6  1.7|
                                            __________________________________________________________________________|____________|
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
      Nasolacrimal Duct, Inflammation,     |                                                                          |            |
           Suppurative                     |                   1                             2                        |      3  1.3|
      Olfactory Epithelium, Atrophy, Focal |                                                                         1|      2  1.0|
                                            __________________________________________________________________________|____________|
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
 _____________________________________________________________________________________________________________________|            |
 SPECIAL SENSES SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Harderian Gland                         |                   +                             +                        |   4        |
 _____________________________________________________________________________________________________________________|            |
 URINARY SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  39                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 7| 7| 6| 7| 7| 7| 7| 7| 4| 7| 6| 5| 7| 6| 6| 7| 7| 5| 7| 7| 7| 7| 7| 7|            |
                             DAY ON TEST   | 2| 3| 3| 9| 3| 3| 3| 3| 3| 8| 3| 4| 5| 3| 3| 9| 3| 3| 8| 3| 3| 3| 3| 3| 3|            |
                                           | 1| 3| 7| 0| 4| 6| 3| 3| 4| 1| 4| 4| 7| 3| 8| 9| 3| 3| 2| 6| 6| 6| 4| 3| 3|      T (*) |
 _____________________________________________________________________________________________________________________|            |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      O     |
   B6C3F1 MICE MALE                        | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      T     |
                               ANIMAL ID   | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      A     |
    CONTROL                                | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|      L     |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 URINARY SYSTEM - cont                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Glomerulosclerosis                   | 4                                                                        |      2  3.0|
      Hydronephrosis                       | 2                                         1                              |      3  1.7|
      Inflammation, Suppurative            |                                              1                           |      3  1.3|
      Nephropathy                          |    1  1     1  1  1  2  1     1        1  1     1  1  3  1  2  1     2  1|     31  1.2|
      Cortex, Cyst                         |                               2  1                                       |      2  1.5|
      Renal Tubule, Hyperplasia            |                      3                                                   |      2  2.5|
                                            __________________________________________________________________________|____________|
   Urinary Bladder                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
      Inflammation, Suppurative            |                                              4                           |      3  3.7|
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  40                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 7| 7| 4| 7| 7| 7| 7| 7| 7| 6| 7| 7| 4| 7| 3| 7| 7| 7| 7| 7| 5| 5| 7| 5|             
                             DAY ON TEST   | 3| 3| 3| 7| 3| 3| 3| 3| 3| 3| 6| 0| 3| 4| 3| 2| 3| 3| 3| 3| 3| 7| 2| 3| 4|             
                                           | 4| 7| 4| 5| 3| 6| 6| 4| 6| 6| 6| 6| 6| 1| 7| 4| 4| 7| 6| 6| 4| 7| 6| 7| 4|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   B6C3F1 MICE MALE                        | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2|             
    200 PPM                                | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
                                           | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 ALIMENTARY SYSTEM                         |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Esophagus                               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Gallbladder                             | +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  A  +  +  +  +  +  A  +  +  +|             
      Degeneration, Hyaline                |                                                                          |             
      Inflammation                         |                                                                          |             
                                            __________________________________________________________________________|             
   Intestine Large, Colon                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  A  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  A  +  +  M  M  +  A  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Cecum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  A  +  +  +  +  +  A  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Duodenum               | +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  A  +  +  +  +  +  A  +  +  +|             
      Ulcer                                |                                                                         2|             
                                            __________________________________________________________________________|             
   Intestine Small, Jejunum                | +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  A  +  +  +  +  +  A  +  +  +|             
      Peyer's Patch, Hyperplasia           |                                                                          |             
                                            __________________________________________________________________________|             
   Intestine Small, Ileum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  A  +  +  +  +  +  A  +  +  +|             
                                            __________________________________________________________________________|             
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Eosinophilic Focus                   |    X           X     3           X                       X               |             
      Hematopoietic Cell Proliferation     |                                                                          |             
      Mixed Cell Focus                     |                                                    X                     |             
      Necrosis                             |                                                                4         |             
      Centrilobular, Necrosis              |                                                                   3      |             
                                            __________________________________________________________________________|             
   Mesentery                               |          +                                         +                     |             
      Fat, Necrosis                        |                                                                          |             
                                            __________________________________________________________________________|             
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  A  +  +  +|             
      Atrophy                              |       1                                                                  |             
      Hypertrophy                          |                                                                          |             
                                            __________________________________________________________________________|             
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  A  +  +  +|             
      Epithelium, Hyperplasia              |                                                    2                     |             
                                            __________________________________________________________________________|             
   Tooth                                   |                                                                          |             
      Developmental Malformation           |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 CARDIOVASCULAR SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Cardiomyopathy                       | 1  1  1        1     1  1  1        1     1     1  1  1              1  1|             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM                          |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hyperplasia                          |    4        2        4                                                   |             
      Hypertrophy                          |    2  4        1           1              1     1  2  2  1           1  1|             
                                            __________________________________________________________________________|             
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hyperplasia                          |                                                                          |             
                                            __________________________________________________________________________|             
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  A  +  +  +|             
      Hyperplasia                          |    2                                                                 2   |             
                                            __________________________________________________________________________|             
   Parathyroid Gland                       | +  +  +  M  +  M  M  +  +  +  M  +  +  +  +  +  M  +  +  M  +  +  +  M  M|             
                                            __________________________________________________________________________|             
   Pituitary Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  I  +  +  +  +  +  M  +  +  +|             
 _____________________________________________________________________________________________________________________|             
                                                             Page  41                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 7| 7| 4| 7| 7| 7| 7| 7| 7| 6| 7| 7| 4| 7| 3| 7| 7| 7| 7| 7| 5| 5| 7| 5|             
                             DAY ON TEST   | 3| 3| 3| 7| 3| 3| 3| 3| 3| 3| 6| 0| 3| 4| 3| 2| 3| 3| 3| 3| 3| 7| 2| 3| 4|             
                                           | 4| 7| 4| 5| 3| 6| 6| 4| 6| 6| 6| 6| 6| 1| 7| 4| 4| 7| 6| 6| 4| 7| 6| 7| 4|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   B6C3F1 MICE MALE                        | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2|             
    200 PPM                                | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
                                           | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM - cont                   |                                                                          |             
                                           |                                                                          |             
      Pars Distalis, Hyperplasia           | 2                                                                        |             
                                            __________________________________________________________________________|             
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Follicular Cell, Hyperplasia         |    1           3  1     1                       1  2  1                  |             
 _____________________________________________________________________________________________________________________|             
 GENERAL BODY SYSTEM                       |                                                                          |             
                                           |                                                                          |             
    None                                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 GENITAL SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Epididymis                              | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Granuloma Sperm                      |                                                                          |             
      Inflammation                         |                                                 2                        |             
                                            __________________________________________________________________________|             
   Penis                                   |                                                                          |             
      Inflammation, Suppurative            |                                                                          |             
                                            __________________________________________________________________________|             
   Preputial Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Cyst                                 |                4                                                         |             
      Inflammation                         |       3        4              4  3  3     4     4  3     4        4      |             
      Duct, Hyperplasia                    |                3                                                         |             
                                            __________________________________________________________________________|             
   Prostate                                | +  +  M  +  +  +  M  +  +  +  +  +  +  +  M  +  +  M  M  +  M  +  +  +  +|             
      Inflammation, Suppurative            |                                              1                           |             
                                            __________________________________________________________________________|             
   Seminal Vesicle                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  A  +  +  +|             
      Inflammation, Chronic                |                                                       4                  |             
                                            __________________________________________________________________________|             
   Testes                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Atrophy                              |                   3                             2                        |             
      Interstitial Cell, Hyperplasia       |                                                 2                        |             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hyperplasia                          |                                                 2                        |             
                                            __________________________________________________________________________|             
   Lymph Node                              |                                                    +                     |             
      Iliac, Hyperplasia                   |                                                                          |             
      Renal, Hyperplasia                   |                                                    2                     |             
                                            __________________________________________________________________________|             
   Lymph Node, Bronchial                   | +  M  +  +  M  M  M  +  +  +  +  +  +  M  +  +  +  +  M  M  +  M  +  M  M|             
      Hyperplasia                          |                         2     2                    2                     |             
                                            __________________________________________________________________________|             
   Lymph Node, Mandibular                  | +  +  +  +  +  M  +  +  +  M  +  +  M  +  M  +  M  +  +  M  +  +  M  +  +|             
      Hyperplasia                          |                                                                          |             
                                            __________________________________________________________________________|             
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  A  +  +  +|             
      Angiectasis                          |                                                                          |             
      Congestion                           |                                                 2                        |             
      Hematopoietic Cell Proliferation     |                                                 2                        |             
      Hyperplasia                          |                                                                          |             
                                            __________________________________________________________________________|             
   Lymph Node, Mediastinal                 | +  +  +  +  +  +  +  +  +  +  +  M  +  M  +  M  +  +  +  +  +  +  +  M  M|             
      Hyperplasia                          |             3                                                            |             
                                            __________________________________________________________________________|             
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +|             
      Hematopoietic Cell Proliferation     |          2                       2        2                             2|             
 _____________________________________________________________________________________________________________________|             
                                                             Page  42                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 7| 7| 4| 7| 7| 7| 7| 7| 7| 6| 7| 7| 4| 7| 3| 7| 7| 7| 7| 7| 5| 5| 7| 5|             
                             DAY ON TEST   | 3| 3| 3| 7| 3| 3| 3| 3| 3| 3| 6| 0| 3| 4| 3| 2| 3| 3| 3| 3| 3| 7| 2| 3| 4|             
                                           | 4| 7| 4| 5| 3| 6| 6| 4| 6| 6| 6| 6| 6| 1| 7| 4| 4| 7| 6| 6| 4| 7| 6| 7| 4|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   B6C3F1 MICE MALE                        | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2|             
    200 PPM                                | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
                                           | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM - cont               |                                                                          |             
                                           |                                                                          |             
      Hyperplasia, Lymphoid                |                   2  2                                                   |             
                                            __________________________________________________________________________|             
   Thymus                                  | +  +  +  +  +  M  M  M  +  +  +  I  +  +  +  +  M  +  +  +  M  M  +  +  M|             
      Atrophy                              |                                                                   3      |             
 _____________________________________________________________________________________________________________________|             
 INTEGUMENTARY SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Mammary Gland                           | M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  +  M  M  M  M  +|             
                                            __________________________________________________________________________|             
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Inflammation, Suppurative            |                   4                                                      |             
      Prepuce, Inflammation, Suppurative   |                                              4  4                       2|             
      Subcutaneous Tissue, Infiltration    |                                                                          |             
          Cellular, Mast Cell              |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM                    |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Fibrous Osteodystrophy               |       1                                                                  |             
                                            __________________________________________________________________________|             
   Skeletal Muscle                         |          +                                                               |             
 _____________________________________________________________________________________________________________________|             
 NERVOUS SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 RESPIRATORY SYSTEM                        |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +|             
      Epiglottis, Metaplasia, Squamous     |             1                                                        1   |             
                                            __________________________________________________________________________|             
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Infiltration Cellular, Histiocyte    |             3           3     3           2                          3   |             
      Inflammation, Chronic, Focal         |                               2                                      2   |             
      Pigmentation, Hemosiderin            |                                           2                              |             
      Alveolar Epithelium, Hyperplasia     |       2                                                                  |             
      Perivascular, Infiltration Cellular, |                                                                          |             
           Mononuclear Cell                |                                                                      2   |             
                                            __________________________________________________________________________|             
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Inflammation, Suppurative            |                                                                   1  1   |             
      Nasolacrimal Duct, Inflammation,     |                                                                          |             
           Suppurative                     |                                                                          |             
      Olfactory Epithelium, Atrophy, Focal |                                                                          |             
                                            __________________________________________________________________________|             
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  A  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 SPECIAL SENSES SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Harderian Gland                         |    +                                                                     |             
                                            __________________________________________________________________________|             
   Lacrimal Gland                          |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hydronephrosis                       |                                                                          |             
 _____________________________________________________________________________________________________________________|             
                                                             Page  43                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 7| 7| 4| 7| 7| 7| 7| 7| 7| 6| 7| 7| 4| 7| 3| 7| 7| 7| 7| 7| 5| 5| 7| 5|             
                             DAY ON TEST   | 3| 3| 3| 7| 3| 3| 3| 3| 3| 3| 6| 0| 3| 4| 3| 2| 3| 3| 3| 3| 3| 7| 2| 3| 4|             
                                           | 4| 7| 4| 5| 3| 6| 6| 4| 6| 6| 6| 6| 6| 1| 7| 4| 4| 7| 6| 6| 4| 7| 6| 7| 4|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   B6C3F1 MICE MALE                        | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2|             
    200 PPM                                | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
                                           | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM - cont                     |                                                                          |             
                                           |                                                                          |             
      Inflammation, Suppurative            |                                              2                           |             
      Metaplasia, Osseous                  |                                                                          |             
      Nephropathy                          | 1  1  1     1  1  1  1  1  1  1  1  1  3  2     1  2  1  1  1        1  4|             
      Cortex, Cyst                         |                               1                                          |             
      Renal Tubule, Hyperplasia            |       1                                                     1            |             
                                            __________________________________________________________________________|             
   Ureter                                  |                                                                          |             
      Inflammation, Suppurative            |                                                                          |             
                                            __________________________________________________________________________|             
   Urethra                                 |                                              +                           |             
      Inflammation, Suppurative            |                                              2                           |             
                                            __________________________________________________________________________|             
   Urinary Bladder                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +|             
      Calculus Micro Observation Only      |                                                                          |             
      Inflammation, Suppurative            |                                              2                           |             
      Transitional Epithelium, Hyperplasia |                                                                          |             
 _____________________________________________________________________________________________________________________|             
                                                             Page  44                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 7| 7| 6| 7| 6| 7| 3| 7| 5| 7| 6| 7| 5| 5| 7| 7| 7| 5| 6| 7| 7| 7| 6| 7|            |
                             DAY ON TEST   | 3| 3| 3| 4| 3| 9| 1| 1| 3| 5| 3| 3| 3| 3| 5| 3| 3| 3| 7| 8| 3| 3| 3| 4| 3|            |
                                           | 3| 7| 4| 4| 4| 4| 3| 4| 4| 4| 6| 8| 4| 2| 4| 7| 7| 3| 4| 5| 3| 6| 7| 6| 7|      T (*) |
 _____________________________________________________________________________________________________________________|            |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      O     |
   B6C3F1 MICE MALE                        | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      T     |
                               ANIMAL ID   | 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2|      A     |
    200 PPM                                | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|      L     |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 ALIMENTARY SYSTEM                         |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Esophagus                               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Gallbladder                             | +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  46        |
      Degeneration, Hyaline                |             2                                                            |      1  2.0|
      Inflammation                         |                                              1                           |      1  1.0|
                                            __________________________________________________________________________|____________|
   Intestine Large, Colon                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  45        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Cecum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  47        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Duodenum               | +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  A  +  +  +  +  +  +|  45        |
      Ulcer                                |                                                                          |      1  2.0|
                                            __________________________________________________________________________|____________|
   Intestine Small, Jejunum                | +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  A  +  +  +  +  +  +|  45        |
      Peyer's Patch, Hyperplasia           |                            4                                             |      1  4.0|
                                            __________________________________________________________________________|____________|
   Intestine Small, Ileum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +|  46        |
                                            __________________________________________________________________________|____________|
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Eosinophilic Focus                   | X  X              X                                                      |      8  3.0|
      Hematopoietic Cell Proliferation     | 2                                                                        |      1  2.0|
      Mixed Cell Focus                     |                                                                          |      1     |
      Necrosis                             |          2              4  2              2                              |      5  2.8|
      Centrilobular, Necrosis              |                                                                          |      1  3.0|
                                            __________________________________________________________________________|____________|
   Mesentery                               |             +                                                            |   3        |
      Fat, Necrosis                        |             2                                                            |      1  2.0|
                                            __________________________________________________________________________|____________|
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
      Atrophy                              |    1        4                          2                                 |      4  2.0|
      Hypertrophy                          |                                                       1                  |      1  1.0|
                                            __________________________________________________________________________|____________|
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
      Epithelium, Hyperplasia              |    1                                                                     |      2  1.5|
                                            __________________________________________________________________________|____________|
   Tooth                                   |                   +                                                      |   1        |
      Developmental Malformation           |                   X                                                      |      1     |
 _____________________________________________________________________________________________________________________|            |
 CARDIOVASCULAR SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Cardiomyopathy                       | 1  1  1     1  1  1     1  1  1  1  1  1  1  1  1  1     1  1  1  1  1  1|     36  1.0|
 _____________________________________________________________________________________________________________________|            |
 ENDOCRINE SYSTEM                          |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hyperplasia                          |                                     2        2                           |      5  2.8|
      Hypertrophy                          |    2  1     1           1  2  2     2           1        2     2  2  1  1|     24  1.5|
                                            __________________________________________________________________________|____________|
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  45                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 7| 7| 6| 7| 6| 7| 3| 7| 5| 7| 6| 7| 5| 5| 7| 7| 7| 5| 6| 7| 7| 7| 6| 7|            |
                             DAY ON TEST   | 3| 3| 3| 4| 3| 9| 1| 1| 3| 5| 3| 3| 3| 3| 5| 3| 3| 3| 7| 8| 3| 3| 3| 4| 3|            |
                                           | 3| 7| 4| 4| 4| 4| 3| 4| 4| 4| 6| 8| 4| 2| 4| 7| 7| 3| 4| 5| 3| 6| 7| 6| 7|      T (*) |
 _____________________________________________________________________________________________________________________|            |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      O     |
   B6C3F1 MICE MALE                        | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      T     |
                               ANIMAL ID   | 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2|      A     |
    200 PPM                                | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|      L     |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 ENDOCRINE SYSTEM - cont                   |                                                                          |            |
                                           |                                                                          |            |
      Hyperplasia                          |             1           2                                                |      2  1.5|
                                            __________________________________________________________________________|____________|
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
      Hyperplasia                          |                                                                          |      2  2.0|
                                            __________________________________________________________________________|____________|
   Parathyroid Gland                       | M  +  M  +  +  +  M  +  +  +  M  +  I  M  I  +  +  M  +  +  +  +  +  M  M|  32        |
                                            __________________________________________________________________________|____________|
   Pituitary Gland                         | +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  47        |
      Pars Distalis, Hyperplasia           |                   1                                                      |      2  1.5|
                                            __________________________________________________________________________|____________|
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Follicular Cell, Hyperplasia         |                   1     2        1  1  1                                 |     12  1.3|
 _____________________________________________________________________________________________________________________|            |
 GENERAL BODY SYSTEM                       |                                                                          |            |
                                           |                                                                          |            |
    None                                   |                                                                          |            |
 _____________________________________________________________________________________________________________________|            |
 GENITAL SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Epididymis                              | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Granuloma Sperm                      |                   2                                                      |      1  2.0|
      Inflammation                         |                                                                          |      1  2.0|
                                            __________________________________________________________________________|____________|
   Penis                                   |             +        +                                                   |   2        |
      Inflammation, Suppurative            |             2                                                            |      1  2.0|
                                            __________________________________________________________________________|____________|
   Preputial Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +|  49        |
      Cyst                                 |          2                                                  3            |      3  3.0|
      Inflammation                         |             2  4  3                 4           4                       3|     16  3.5|
      Duct, Hyperplasia                    |                                                                          |      1  3.0|
                                            __________________________________________________________________________|____________|
   Prostate                                | +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +|  43        |
      Inflammation, Suppurative            |                      2           2                                   2   |      4  1.8|
                                            __________________________________________________________________________|____________|
   Seminal Vesicle                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
      Inflammation, Chronic                |                                                                      2   |      2  3.0|
                                            __________________________________________________________________________|____________|
   Testes                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Atrophy                              |                            1                                             |      3  2.0|
      Interstitial Cell, Hyperplasia       |                                                                          |      1  2.0|
 _____________________________________________________________________________________________________________________|            |
 HEMATOPOIETIC SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hyperplasia                          |                2     4  2                                3           2   |      6  2.5|
                                            __________________________________________________________________________|____________|
   Lymph Node                              |                         +        +                                   +   |   4        |
      Iliac, Hyperplasia                   |                         2        3                                   4   |      3  3.0|
      Renal, Hyperplasia                   |                                                                          |      1  2.0|
                                            __________________________________________________________________________|____________|
   Lymph Node, Bronchial                   | +  +  M  M  +  +  +  +  M  M  +  M  +  +  +  +  +  M  M  +  +  +  M  +  +|  32        |
      Hyperplasia                          |                                                                          |      3  2.0|
                                            __________________________________________________________________________|____________|
   Lymph Node, Mandibular                  | +  +  +  +  +  +  M  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  M  +|  40        |
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  46                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 7| 7| 6| 7| 6| 7| 3| 7| 5| 7| 6| 7| 5| 5| 7| 7| 7| 5| 6| 7| 7| 7| 6| 7|            |
                             DAY ON TEST   | 3| 3| 3| 4| 3| 9| 1| 1| 3| 5| 3| 3| 3| 3| 5| 3| 3| 3| 7| 8| 3| 3| 3| 4| 3|            |
                                           | 3| 7| 4| 4| 4| 4| 3| 4| 4| 4| 6| 8| 4| 2| 4| 7| 7| 3| 4| 5| 3| 6| 7| 6| 7|      T (*) |
 _____________________________________________________________________________________________________________________|            |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      O     |
   B6C3F1 MICE MALE                        | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      T     |
                               ANIMAL ID   | 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2|      A     |
    200 PPM                                | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|      L     |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 HEMATOPOIETIC SYSTEM - cont               |                                                                          |            |
                                           |                                                                          |            |
      Hyperplasia                          |                                                                   2      |      1  2.0|
                                            __________________________________________________________________________|____________|
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
      Angiectasis                          |                         2                                                |      1  2.0|
      Congestion                           |                                                                          |      1  2.0|
      Hematopoietic Cell Proliferation     |                         2                                                |      2  2.0|
      Hyperplasia                          |                                                 2                        |      1  2.0|
                                            __________________________________________________________________________|____________|
   Lymph Node, Mediastinal                 | +  +  +  +  M  +  +  M  +  +  +  +  +  +  +  +  +  +  M  I  +  +  +  M  +|  40        |
      Hyperplasia                          | 2                                                                        |      2  2.5|
                                            __________________________________________________________________________|____________|
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Hematopoietic Cell Proliferation     |          2  2  2     2  2        2        2              2           3   |     13  2.1|
      Hyperplasia, Lymphoid                |                                                                          |      2  2.0|
                                            __________________________________________________________________________|____________|
   Thymus                                  | M  +  +  M  M  +  I  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +|  37        |
      Atrophy                              |                                  2                                       |      2  2.5|
 _____________________________________________________________________________________________________________________|            |
 INTEGUMENTARY SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Mammary Gland                           | M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M|   2        |
                                            __________________________________________________________________________|____________|
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Inflammation, Suppurative            |                                                                          |      1  4.0|
      Prepuce, Inflammation, Suppurative   |                                  4        4              4           4   |      7  3.7|
      Subcutaneous Tissue, Infiltration    |                                                                          |            |
          Cellular, Mast Cell              |                               2                                          |      1  2.0|
 _____________________________________________________________________________________________________________________|            |
 MUSCULOSKELETAL SYSTEM                    |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Fibrous Osteodystrophy               |             1                                                            |      2  1.0|
                                            __________________________________________________________________________|____________|
   Skeletal Muscle                         |                                                                          |   1        |
 _____________________________________________________________________________________________________________________|            |
 NERVOUS SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 RESPIRATORY SYSTEM                        |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Epiglottis, Metaplasia, Squamous     |                                                                          |      2  1.0|
                                            __________________________________________________________________________|____________|
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Infiltration Cellular, Histiocyte    |          2                                                  2            |      7  2.6|
      Inflammation, Chronic, Focal         |                                                                          |      2  2.0|
      Pigmentation, Hemosiderin            |                                                                          |      1  2.0|
      Alveolar Epithelium, Hyperplasia     |                                                                          |      1  2.0|
      Perivascular, Infiltration Cellular, |                                                                          |            |
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  47                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 7| 7| 6| 7| 6| 7| 3| 7| 5| 7| 6| 7| 5| 5| 7| 7| 7| 5| 6| 7| 7| 7| 6| 7|            |
                             DAY ON TEST   | 3| 3| 3| 4| 3| 9| 1| 1| 3| 5| 3| 3| 3| 3| 5| 3| 3| 3| 7| 8| 3| 3| 3| 4| 3|            |
                                           | 3| 7| 4| 4| 4| 4| 3| 4| 4| 4| 6| 8| 4| 2| 4| 7| 7| 3| 4| 5| 3| 6| 7| 6| 7|      T (*) |
 _____________________________________________________________________________________________________________________|            |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      O     |
   B6C3F1 MICE MALE                        | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      T     |
                               ANIMAL ID   | 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2| 2|      A     |
    200 PPM                                | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|      L     |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 RESPIRATORY SYSTEM - cont                 |                                                                          |            |
                                           |                                                                          |            |
           Mononuclear Cell                |                                                                          |      1  2.0|
                                            __________________________________________________________________________|____________|
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Inflammation, Suppurative            |                   1                                                      |      3  1.0|
      Nasolacrimal Duct, Inflammation,     |                                                                          |            |
           Suppurative                     |             2                                                            |      1  2.0|
      Olfactory Epithelium, Atrophy, Focal |                                                             2            |      1  2.0|
                                            __________________________________________________________________________|____________|
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
 _____________________________________________________________________________________________________________________|            |
 SPECIAL SENSES SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Harderian Gland                         |          +  +                                                     +      |   4        |
                                            __________________________________________________________________________|____________|
   Lacrimal Gland                          |                   +                                                      |   1        |
 _____________________________________________________________________________________________________________________|            |
 URINARY SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hydronephrosis                       |                      2  2                                            1   |      3  1.7|
      Inflammation, Suppurative            |                      1  2        2                                   2   |      5  1.8|
      Metaplasia, Osseous                  |                                                                   1      |      1  1.0|
      Nephropathy                          | 1  1  1  2  2  3  1           1     1     1  1  1  1     1  1  1  1  1  1|     40  1.3|
      Cortex, Cyst                         |                                                                          |      1  1.0|
      Renal Tubule, Hyperplasia            |                                                                          |      2  1.0|
                                            __________________________________________________________________________|____________|
   Ureter                                  |                                  +                                       |   1        |
      Inflammation, Suppurative            |                                  2                                       |      1  2.0|
                                            __________________________________________________________________________|____________|
   Urethra                                 |                         +        +                                       |   3        |
      Inflammation, Suppurative            |                         2        4                                       |      3  2.7|
                                            __________________________________________________________________________|____________|
   Urinary Bladder                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Calculus Micro Observation Only      |                      X                                                   |      1     |
      Inflammation, Suppurative            |                      4  4        4                       1           3   |      6  3.0|
      Transitional Epithelium, Hyperplasia |                         3                                                |      1  3.0|
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  48                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 6| 7| 7| 7| 7| 6| 7| 7| 5| 6| 7| 7| 6| 7| 7| 5| 5| 7| 7| 7| 5| 7| 6| 5|             
                             DAY ON TEST   | 3| 9| 3| 3| 3| 3| 3| 3| 3| 5| 0| 3| 3| 6| 3| 3| 1| 9| 3| 3| 3| 5| 3| 5| 6|             
                                           | 6| 4| 3| 4| 7| 4| 1| 6| 3| 8| 4| 4| 6| 6| 6| 4| 2| 4| 4| 4| 7| 1| 4| 8| 9|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   B6C3F1 MICE MALE                        | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4|             
    600 PPM                                | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
                                           | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 ALIMENTARY SYSTEM                         |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Esophagus                               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Gallbladder                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  M  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Colon                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Rectum                 | M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Large, Cecum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Duodenum               | M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +|             
                                            __________________________________________________________________________|             
   Intestine Small, Jejunum                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +|             
      Peyer's Patch, Hyperplasia           |                                              2                           |             
                                            __________________________________________________________________________|             
   Intestine Small, Ileum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +|             
      Peyer's Patch, Hyperplasia           |       4                                                                  |             
      Peyer's Patch, Inflammation          |       3                                                                  |             
                                            __________________________________________________________________________|             
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Basophilic Focus                     |                                                                          |             
      Clear Cell Focus                     |                                                                   X      |             
      Eosinophilic Focus                   | X                    3           X     X                    X     X  X   |             
      Hematopoietic Cell Proliferation     |                                                                          |             
      Inflammation, Chronic                |                         2                                                |             
      Necrosis                             |                      4  4  1                    3                        |             
                                            __________________________________________________________________________|             
   Mesentery                               |                      +                                                   |             
      Fat, Necrosis                        |                                                                          |             
                                            __________________________________________________________________________|             
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Basophilic Focus                     |                                                                   X      |             
                                            __________________________________________________________________________|             
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Basophilic Focus                     |                                                                          |             
                                            __________________________________________________________________________|             
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hyperplasia                          |                                                                          |             
                                            __________________________________________________________________________|             
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +|             
      Erosion                              |                                                 3                        |             
      Infiltration Cellular, Mast Cell     |                                                                          |             
                                            __________________________________________________________________________|             
   Tooth                                   |                                        +     +                           |             
      Developmental Malformation           |                                              X                           |             
 _____________________________________________________________________________________________________________________|             
 CARDIOVASCULAR SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Blood Vessel                            |                                                                      +   |             
      Aorta, Inflammation                  |                                                                      2   |             
      Aorta, Pigmentation, Hemosiderin     |                                                                      2   |             
                                            __________________________________________________________________________|             
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Cardiomyopathy                       | 1  1  1     1  1  1  1  2  1              1  1     1     1  1  1  1  2  1|             
      Hyperplasia, Atypical                |                         2                                                |             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM                          |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +|             
      Hemorrhage                           |                                                                          |             
      Hyperplasia                          |                               1                       1     4     2      |             
 _____________________________________________________________________________________________________________________|             
                                                             Page  49                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 6| 7| 7| 7| 7| 6| 7| 7| 5| 6| 7| 7| 6| 7| 7| 5| 5| 7| 7| 7| 5| 7| 6| 5|             
                             DAY ON TEST   | 3| 9| 3| 3| 3| 3| 3| 3| 3| 5| 0| 3| 3| 6| 3| 3| 1| 9| 3| 3| 3| 5| 3| 5| 6|             
                                           | 6| 4| 3| 4| 7| 4| 1| 6| 3| 8| 4| 4| 6| 6| 6| 4| 2| 4| 4| 4| 7| 1| 4| 8| 9|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   B6C3F1 MICE MALE                        | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4|             
    600 PPM                                | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
                                           | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM - cont                   |                                                                          |             
                                           |                                                                          |             
      Hypertrophy                          | 1     2     1        1           1  2  1           1              2      |             
      Capsule, Hyperplasia                 |                      3                                                   |             
                                            __________________________________________________________________________|             
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +|             
                                            __________________________________________________________________________|             
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hyperplasia                          |                                              1  1                        |             
                                            __________________________________________________________________________|             
   Parathyroid Gland                       | +  +  +  +  M  +  +  +  M  +  M  +  +  +  M  +  +  +  +  M  I  M  +  +  +|             
                                            __________________________________________________________________________|             
   Pituitary Gland                         | +  +  +  +  +  +  I  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M|             
      Pars Distalis, Cyst                  |                                                                          |             
      Pars Distalis, Hyperplasia           |                                                                   1      |             
                                            __________________________________________________________________________|             
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +|             
      Follicular Cell, Hyperplasia         | 2                       2                          1     1               |             
 _____________________________________________________________________________________________________________________|             
 GENERAL BODY SYSTEM                       |                                                                          |             
                                           |                                                                          |             
    None                                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 GENITAL SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Coagulating Gland                       |                                                    +                     |             
      Inflammation, Suppurative            |                                                    2                     |             
                                            __________________________________________________________________________|             
   Epididymis                              | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Granuloma Sperm                      |                                                                          |             
                                            __________________________________________________________________________|             
   Penis                                   |                                                                          |             
      Inflammation, Suppurative            |                                                                          |             
                                            __________________________________________________________________________|             
   Preputial Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Cyst                                 |                                  3                                       |             
      Inflammation                         |       1                 2        4                                   2   |             
                                            __________________________________________________________________________|             
   Prostate                                | +  M  +  +  +  +  M  +  +  M  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +|             
      Inflammation, Suppurative            |                                                                          |             
                                            __________________________________________________________________________|             
   Seminal Vesicle                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +|             
      Angiectasis                          |                                              1                           |             
                                            __________________________________________________________________________|             
   Testes                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Atrophy                              | 1                       1                                                |             
      Mineralization                       | 1                                                                        |             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hyperplasia                          |                   2     2  2                       3                     |             
      Infiltration Cellular, Mast Cell     |                                                                          |             
                                            __________________________________________________________________________|             
   Lymph Node                              |                                                    +                     |             
      Iliac, Hyperplasia                   |                                                    2                     |             
                                            __________________________________________________________________________|             
   Lymph Node, Bronchial                   | +  +  +  +  +  +  +  M  +  +  +  +  +  M  +  +  M  M  +  +  +  M  +  M  M|             
      Hyperplasia                          |                               2                                          |             
                                            __________________________________________________________________________|             
   Lymph Node, Mandibular                  | +  +  +  +  +  +  M  +  +  M  +  +  M  +  +  +  I  +  +  +  +  +  M  +  +|             
                                            __________________________________________________________________________|             
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  +  I  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +|             
      Angiectasis                          |                                                                         1|             
 _____________________________________________________________________________________________________________________|             
                                                             Page  50                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 6| 7| 7| 7| 7| 6| 7| 7| 5| 6| 7| 7| 6| 7| 7| 5| 5| 7| 7| 7| 5| 7| 6| 5|             
                             DAY ON TEST   | 3| 9| 3| 3| 3| 3| 3| 3| 3| 5| 0| 3| 3| 6| 3| 3| 1| 9| 3| 3| 3| 5| 3| 5| 6|             
                                           | 6| 4| 3| 4| 7| 4| 1| 6| 3| 8| 4| 4| 6| 6| 6| 4| 2| 4| 4| 4| 7| 1| 4| 8| 9|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   B6C3F1 MICE MALE                        | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4|             
    600 PPM                                | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
                                           | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM - cont               |                                                                          |             
                                           |                                                                          |             
      Hyperplasia                          |       3                                                  4               |             
                                            __________________________________________________________________________|             
   Lymph Node, Mediastinal                 | +  +  +  M  I  +  M  +  +  M  +  +  M  +  +  +  +  +  M  +  +  +  +  +  +|             
      Hyperplasia                          |                                                                          |             
                                            __________________________________________________________________________|             
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +|             
      Hematopoietic Cell Proliferation     |                   2     2  2                       2                 2  2|             
      Hyperplasia, Lymphoid                |       2                                               2                  |             
                                            __________________________________________________________________________|             
   Thymus                                  | M  +  +  +  +  +  +  +  M  +  M  +  +  +  +  M  M  M  +  +  +  +  +  M  M|             
      Atrophy                              |                                                                          |             
      Hyperplasia, Lymphoid                |                                  2                                       |             
 _____________________________________________________________________________________________________________________|             
 INTEGUMENTARY SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Mammary Gland                           | M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M|             
                                            __________________________________________________________________________|             
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Inflammation, Suppurative            |                            4                          2                  |             
      Prepuce, Inflammation, Suppurative   |                   4     3                          4                     |             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM                    |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Fibrous Osteodystrophy               |                                                                          |             
      Synovial Tissue, Inflammation,       |                                                                          |             
          Chronic                          |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 NERVOUS SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 RESPIRATORY SYSTEM                        |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +|             
      Epiglottis, Metaplasia, Squamous     |                                                                          |             
                                            __________________________________________________________________________|             
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hemorrhage                           |                                                                          |             
      Infiltration Cellular, Histiocyte    |       2                       4                                      1   |             
      Inflammation, Chronic, Focal         |                                                                          |             
      Alveolar Epithelium, Hyperplasia     |                                              1                           |             
                                            __________________________________________________________________________|             
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Fibrosis                             |                                                                          |             
      Inflammation, Suppurative            |                                        1     1                           |             
      Olfactory Epithelium, Atrophy, Focal |                                        3     3     1                     |             
                                            __________________________________________________________________________|             
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 SPECIAL SENSES SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Harderian Gland                         |                                                             +            |             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +|             
 _____________________________________________________________________________________________________________________|             
                                                             Page  51                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 7| 6| 7| 7| 7| 7| 6| 7| 7| 5| 6| 7| 7| 6| 7| 7| 5| 5| 7| 7| 7| 5| 7| 6| 5|             
                             DAY ON TEST   | 3| 9| 3| 3| 3| 3| 3| 3| 3| 5| 0| 3| 3| 6| 3| 3| 1| 9| 3| 3| 3| 5| 3| 5| 6|             
                                           | 6| 4| 3| 4| 7| 4| 1| 6| 3| 8| 4| 4| 6| 6| 6| 4| 2| 4| 4| 4| 7| 1| 4| 8| 9|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   B6C3F1 MICE MALE                        | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4|             
    600 PPM                                | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
                                           | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM - cont                     |                                                                          |             
                                           |                                                                          |             
      Hydronephrosis                       | 2                 2        3                                             |             
      Inflammation, Suppurative            |                   2                                                      |             
      Metaplasia, Osseous                  |                                                          1               |             
      Mineralization                       |                                                                          |             
      Nephropathy                          |    1  1  1  1  1     1  1        1  1  1  1  1     1     1  1     1  1  3|             
      Renal Tubule, Hyperplasia            |          1                                                               |             
                                            __________________________________________________________________________|             
   Urethra                                 |                                                                          |             
      Inflammation, Suppurative            |                                                                          |             
      Necrosis                             |                                                                          |             
                                            __________________________________________________________________________|             
   Urinary Bladder                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +|             
      Inflammation, Suppurative            |                   4                                4                     |             
      Transitional Epithelium, Hyperplasia |                                                    3                     |             
 _____________________________________________________________________________________________________________________|             
                                                             Page  52                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 7| 7| 6| 7| 7| 5| 7| 3| 7| 5| 7| 5| 5| 7| 4| 5| 5| 5| 7| 7| 5| 7| 7| 7|            |
                             DAY ON TEST   | 3| 3| 3| 4| 2| 3| 0| 3| 7| 3| 6| 3| 9| 7| 3| 4| 9| 5| 7| 3| 3| 8| 3| 3| 3|            |
                                           | 3| 6| 3| 4| 1| 4| 4| 4| 6| 6| 0| 3| 5| 4| 6| 0| 4| 4| 4| 7| 4| 2| 3| 3| 3|      T (*) |
 _____________________________________________________________________________________________________________________|            |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      O     |
   B6C3F1 MICE MALE                        | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      T     |
                               ANIMAL ID   | 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4|      A     |
    600 PPM                                | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|      L     |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 ALIMENTARY SYSTEM                         |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Esophagus                               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Gallbladder                             | +  +  +  A  +  +  +  +  A  +  +  +  +  +  +  A  +  +  I  +  +  +  +  +  +|  44        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Colon                  | +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Rectum                 | +  +  +  A  +  +  +  +  A  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +|  45        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Cecum                  | +  +  +  A  +  +  +  +  A  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +|  46        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Duodenum               | +  +  +  A  +  +  +  +  A  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +|  45        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Jejunum                | +  +  +  A  +  +  +  +  A  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +|  46        |
      Peyer's Patch, Hyperplasia           |                                                                          |      1  2.0|
                                            __________________________________________________________________________|____________|
   Intestine Small, Ileum                  | +  +  +  A  +  +  +  +  A  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +|  46        |
      Peyer's Patch, Hyperplasia           |                                                                          |      1  4.0|
      Peyer's Patch, Inflammation          |                                                                          |      1  3.0|
                                            __________________________________________________________________________|____________|
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Basophilic Focus                     |    X                                                                     |      1     |
      Clear Cell Focus                     |                                                             X            |      2     |
      Eosinophilic Focus                   |                            X                                3           X|     10  3.0|
      Hematopoietic Cell Proliferation     |                                        2                                 |      1  2.0|
      Inflammation, Chronic                |                                                                          |      1  2.0|
      Necrosis                             |                                     1                          4         |      6  2.8|
                                            __________________________________________________________________________|____________|
   Mesentery                               |                               +                                          |   2        |
      Fat, Necrosis                        |                               2                                          |      1  2.0|
                                            __________________________________________________________________________|____________|
   Pancreas                                | +  +  +  A  +  +  +  +  A  +  +  +  +  I  +  A  +  +  +  +  +  +  +  +  +|  46        |
      Basophilic Focus                     |                                                                          |      1     |
                                            __________________________________________________________________________|____________|
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Basophilic Focus                     |                                                 X                        |      1     |
                                            __________________________________________________________________________|____________|
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +|  48        |
      Hyperplasia                          |                3                                                         |      1  3.0|
                                            __________________________________________________________________________|____________|
   Stomach, Glandular                      | +  +  +  A  +  +  +  +  A  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +|  46        |
      Erosion                              |                                                                          |      1  3.0|
      Infiltration Cellular, Mast Cell     |       1                                                                  |      1  1.0|
                                            __________________________________________________________________________|____________|
   Tooth                                   |                                                                          |   2        |
      Developmental Malformation           |                                                                          |      1     |
 _____________________________________________________________________________________________________________________|            |
 CARDIOVASCULAR SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Blood Vessel                            |                                                                          |   1        |
      Aorta, Inflammation                  |                                                                          |      1  2.0|
      Aorta, Pigmentation, Hemosiderin     |                                                                          |      1  2.0|
                                            __________________________________________________________________________|____________|
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Cardiomyopathy                       | 1  1  2     1     1  1     1     1     1  1     1     1  1  1     1  1  1|     35  1.1|
      Hyperplasia, Atypical                |                                                                          |      1  2.0|
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  53                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 7| 7| 6| 7| 7| 5| 7| 3| 7| 5| 7| 5| 5| 7| 4| 5| 5| 5| 7| 7| 5| 7| 7| 7|            |
                             DAY ON TEST   | 3| 3| 3| 4| 2| 3| 0| 3| 7| 3| 6| 3| 9| 7| 3| 4| 9| 5| 7| 3| 3| 8| 3| 3| 3|            |
                                           | 3| 6| 3| 4| 1| 4| 4| 4| 6| 6| 0| 3| 5| 4| 6| 0| 4| 4| 4| 7| 4| 2| 3| 3| 3|      T (*) |
 _____________________________________________________________________________________________________________________|            |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      O     |
   B6C3F1 MICE MALE                        | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      T     |
                               ANIMAL ID   | 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4|      A     |
    600 PPM                                | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|      L     |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 CARDIOVASCULAR SYSTEM - cont              |                                                                          |            |
                                           |                                                                          |            |
 _____________________________________________________________________________________________________________________|            |
 ENDOCRINE SYSTEM                          |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Hemorrhage                           | 2                                                                        |      1  2.0|
      Hyperplasia                          |                                                             2     2      |      6  2.0|
      Hypertrophy                          |    1     1  2        2           2  1                 1           1  1  1|     19  1.3|
      Capsule, Hyperplasia                 |                                                                          |      1  3.0|
                                            __________________________________________________________________________|____________|
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
                                            __________________________________________________________________________|____________|
   Islets, Pancreatic                      | +  +  +  A  +  +  +  +  A  +  +  +  +  M  +  A  +  +  +  +  +  +  +  +  +|  46        |
      Hyperplasia                          |                                                                   1      |      3  1.0|
                                            __________________________________________________________________________|____________|
   Parathyroid Gland                       | +  M  M  M  +  +  +  M  M  +  M  +  +  M  +  +  M  +  M  M  M  M  +  +  +|  31        |
                                            __________________________________________________________________________|____________|
   Pituitary Gland                         | +  M  +  +  +  +  +  +  A  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +|  45        |
      Pars Distalis, Cyst                  |       2                                                                  |      1  2.0|
      Pars Distalis, Hyperplasia           |                                                                          |      1  1.0|
                                            __________________________________________________________________________|____________|
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Follicular Cell, Hyperplasia         |       1     1        1                                   1        1      |      9  1.2|
 _____________________________________________________________________________________________________________________|            |
 GENERAL BODY SYSTEM                       |                                                                          |            |
                                           |                                                                          |            |
    None                                   |                                                                          |            |
 _____________________________________________________________________________________________________________________|            |
 GENITAL SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Coagulating Gland                       |                                                                          |   1        |
      Inflammation, Suppurative            |                                                                          |      1  2.0|
                                            __________________________________________________________________________|____________|
   Epididymis                              | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Granuloma Sperm                      |                                  4                                       |      1  4.0|
                                            __________________________________________________________________________|____________|
   Penis                                   |                         +              +                                 |   2        |
      Inflammation, Suppurative            |                                        1                                 |      1  1.0|
                                            __________________________________________________________________________|____________|
   Preputial Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Cyst                                 |                                                                          |      1  3.0|
      Inflammation                         |    3  3  4                                3                          3   |      9  2.8|
                                            __________________________________________________________________________|____________|
   Prostate                                | +  +  +  +  M  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  44        |
      Inflammation, Suppurative            |                   2                    2        2     2                  |      4  2.0|
                                            __________________________________________________________________________|____________|
   Seminal Vesicle                         | +  +  +  A  +  +  +  +  A  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +|  46        |
      Angiectasis                          |                                                                          |      1  1.0|
                                            __________________________________________________________________________|____________|
   Testes                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Atrophy                              |                                                                          |      2  1.0|
      Mineralization                       |                                                                          |      1  1.0|
 _____________________________________________________________________________________________________________________|            |
 HEMATOPOIETIC SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  54                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 7| 7| 6| 7| 7| 5| 7| 3| 7| 5| 7| 5| 5| 7| 4| 5| 5| 5| 7| 7| 5| 7| 7| 7|            |
                             DAY ON TEST   | 3| 3| 3| 4| 2| 3| 0| 3| 7| 3| 6| 3| 9| 7| 3| 4| 9| 5| 7| 3| 3| 8| 3| 3| 3|            |
                                           | 3| 6| 3| 4| 1| 4| 4| 4| 6| 6| 0| 3| 5| 4| 6| 0| 4| 4| 4| 7| 4| 2| 3| 3| 3|      T (*) |
 _____________________________________________________________________________________________________________________|            |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      O     |
   B6C3F1 MICE MALE                        | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      T     |
                               ANIMAL ID   | 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4|      A     |
    600 PPM                                | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|      L     |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 HEMATOPOIETIC SYSTEM - cont               |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone Marrow                             | +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Hyperplasia                          |                                        3        2     4                  |      7  2.6|
      Infiltration Cellular, Mast Cell     |       2                                   3                              |      2  2.5|
                                            __________________________________________________________________________|____________|
   Lymph Node                              |                   +                             +     +                  |   4        |
      Iliac, Hyperplasia                   |                                                 2     2                  |      3  2.0|
                                            __________________________________________________________________________|____________|
   Lymph Node, Bronchial                   | +  +  +  +  M  +  M  +  M  +  +  +  M  +  +  +  M  +  M  +  +  M  +  +  +|  36        |
      Hyperplasia                          |                                                                          |      1  2.0|
                                            __________________________________________________________________________|____________|
   Lymph Node, Mandibular                  | +  +  +  +  +  +  +  +  +  M  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  43        |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mesenteric                  | +  +  +  A  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  46        |
      Angiectasis                          |                                                                          |      1  1.0|
      Hyperplasia                          |                2                                                         |      3  3.0|
                                            __________________________________________________________________________|____________|
   Lymph Node, Mediastinal                 | +  M  +  M  +  +  +  +  +  +  +  +  +  M  +  +  +  +  M  +  +  M  +  +  +|  39        |
      Hyperplasia                          |             2                                                            |      1  2.0|
                                            __________________________________________________________________________|____________|
   Spleen                                  | +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +|  47        |
      Hematopoietic Cell Proliferation     |       2  2                       2     2        2  2  2        2         |     14  2.0|
      Hyperplasia, Lymphoid                |                2                                                         |      3  2.0|
                                            __________________________________________________________________________|____________|
   Thymus                                  | +  +  +  A  M  +  +  +  M  M  +  M  +  +  M  +  M  +  I  +  +  +  +  +  +|  34        |
      Atrophy                              |                   2           1        4           3                     |      4  2.5|
      Hyperplasia, Lymphoid                |                                                                          |      1  2.0|
 _____________________________________________________________________________________________________________________|            |
 INTEGUMENTARY SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Mammary Gland                           | M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M|            |
                                            __________________________________________________________________________|____________|
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  M  +  +  +  +  +|  48        |
      Inflammation, Suppurative            |                                                                          |      2  3.0|
      Prepuce, Inflammation, Suppurative   |                   4                    4        4  1                     |      7  3.4|
 _____________________________________________________________________________________________________________________|            |
 MUSCULOSKELETAL SYSTEM                    |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Fibrous Osteodystrophy               |       1        1                                                         |      2  1.0|
      Synovial Tissue, Inflammation,       |                                                                          |            |
          Chronic                          |                               1                                          |      1  1.0|
 _____________________________________________________________________________________________________________________|            |
 NERVOUS SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +|  49        |
 _____________________________________________________________________________________________________________________|            |
 RESPIRATORY SYSTEM                        |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +|  48        |
      Epiglottis, Metaplasia, Squamous     |                                                             1            |      1  1.0|
                                            __________________________________________________________________________|____________|
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  55                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 7| 7| 7| 6| 7| 7| 5| 7| 3| 7| 5| 7| 5| 5| 7| 4| 5| 5| 5| 7| 7| 5| 7| 7| 7|            |
                             DAY ON TEST   | 3| 3| 3| 4| 2| 3| 0| 3| 7| 3| 6| 3| 9| 7| 3| 4| 9| 5| 7| 3| 3| 8| 3| 3| 3|            |
                                           | 3| 6| 3| 4| 1| 4| 4| 4| 6| 6| 0| 3| 5| 4| 6| 0| 4| 4| 4| 7| 4| 2| 3| 3| 3|      T (*) |
 _____________________________________________________________________________________________________________________|            |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      O     |
   B6C3F1 MICE MALE                        | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      T     |
                               ANIMAL ID   | 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4|      A     |
    600 PPM                                | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|      L     |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 RESPIRATORY SYSTEM - cont                 |                                                                          |            |
                                           |                                                                          |            |
      Hemorrhage                           |                                                    4                     |      1  4.0|
      Infiltration Cellular, Histiocyte    |    4  4     3                                      3                     |      7  3.0|
      Inflammation, Chronic, Focal         |             2                                                            |      1  2.0|
      Alveolar Epithelium, Hyperplasia     |                                                                          |      1  1.0|
                                            __________________________________________________________________________|____________|
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Fibrosis                             |                               3                                          |      1  3.0|
      Inflammation, Suppurative            |                                                                          |      2  1.0|
      Olfactory Epithelium, Atrophy, Focal |          2                                                               |      4  2.3|
                                            __________________________________________________________________________|____________|
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +|  48        |
 _____________________________________________________________________________________________________________________|            |
 SPECIAL SENSES SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Harderian Gland                         |             +                 +                             +            |   4        |
 _____________________________________________________________________________________________________________________|            |
 URINARY SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Hydronephrosis                       |                               2                       2                  |      5  2.2|
      Inflammation, Suppurative            |                   2                    1        3     2                  |      5  2.0|
      Metaplasia, Osseous                  |                                                             1            |      2  1.0|
      Mineralization                       |                                     2                                    |      1  2.0|
      Nephropathy                          | 1  1  1     1  1     1     1     2  1     1        1     1  1        1  2|     33  1.1|
      Renal Tubule, Hyperplasia            |                                                                          |      1  1.0|
                                            __________________________________________________________________________|____________|
   Urethra                                 |                   +                                                      |   1        |
      Inflammation, Suppurative            |                   2                                                      |      1  2.0|
      Necrosis                             |                   2                                                      |      1  2.0|
                                            __________________________________________________________________________|____________|
   Urinary Bladder                         | +  +  +  A  +  +  +  +  A  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +|  46        |
      Inflammation, Suppurative            |                   3                    4        4     4                  |      6  3.8|
      Transitional Epithelium, Hyperplasia |                                                                          |      1  3.0|
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  56                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 2| 2| 7| 2| 2| 1| 4| 3| 7| 2| 7| 2| 5| 3| 7| 7| 6| 2| 1| 6| 3| 7| 1| 7| 3|             
                             DAY ON TEST   | 4| 2| 2| 3| 6| 9| 1| 5| 3| 4| 3| 7| 2| 1| 3| 3| 8| 7| 0| 5| 5| 3| 8| 3| 4|             
                                           | 0| 9| 1| 9| 0| 1| 4| 9| 3| 5| 6| 5| 7| 3| 6| 6| 7| 5| 2| 8| 9| 4| 9| 6| 6|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   B6C3F1 MICE MALE                        | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6|             
    1800 PPM                               | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
                                           | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 ALIMENTARY SYSTEM                         |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Esophagus                               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Gallbladder                             | +  A  +  +  A  +  +  +  +  A  +  A  +  A  +  +  A  +  +  +  +  M  A  +  A|             
      Epithelium, Hyperplasia              |                         1                                                |             
                                            __________________________________________________________________________|             
   Intestine Large, Colon                  | +  A  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A|             
                                            __________________________________________________________________________|             
   Intestine Large, Rectum                 | +  +  +  A  +  +  +  +  +  A  +  +  +  A  +  +  +  +  M  +  +  +  A  +  A|             
                                            __________________________________________________________________________|             
   Intestine Large, Cecum                  | +  A  +  +  A  +  +  +  +  A  +  A  +  A  +  +  A  +  +  +  +  +  A  +  A|             
      Muscularis, Hyperplasia              |                                                          1               |             
                                            __________________________________________________________________________|             
   Intestine Small, Duodenum               | +  A  +  A  +  +  +  +  +  A  +  A  +  M  +  +  A  +  +  +  +  +  A  +  A|             
                                            __________________________________________________________________________|             
   Intestine Small, Jejunum                | +  A  +  A  A  +  +  +  +  A  +  A  A  A  +  +  A  +  A  +  +  +  A  +  A|             
                                            __________________________________________________________________________|             
   Intestine Small, Ileum                  | +  A  +  +  A  +  +  +  +  A  +  A  +  A  +  +  A  +  A  +  +  +  A  +  A|             
                                            __________________________________________________________________________|             
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Angiectasis                          | 1                                                                        |             
      Clear Cell Focus                     |                                              X                           |             
      Eosinophilic Focus                   |                                           X  X                           |             
      Necrosis                             |             2     1                                            1         |             
                                            __________________________________________________________________________|             
   Pancreas                                | +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A|             
      Atrophy                              |                                                                          |             
      Hypertrophy                          |                                                                          |             
                                            __________________________________________________________________________|             
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Stomach, Forestomach                    | +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Ulcer                                |             2                                                            |             
      Epithelium, Hyperplasia              |                                                                          |             
                                            __________________________________________________________________________|             
   Stomach, Glandular                      | +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A|             
      Degeneration, Hyaline                |                                                          2               |             
      Erosion                              |                                     4              2                     |             
      Inflammation, Suppurative            |                                                    2     2               |             
 _____________________________________________________________________________________________________________________|             
 CARDIOVASCULAR SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Cardiomyopathy                       |                   1     1           1        1                 1     1   |             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM                          |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hyperplasia                          |                                           2                              |             
      Hypertrophy                          |                         2                 1  1                           |             
      Capsule, Hyperplasia                 |                                                                          |             
                                            __________________________________________________________________________|             
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hyperplasia                          |                                              1                           |             
                                            __________________________________________________________________________|             
   Islets, Pancreatic                      | +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A|             
      Hyperplasia                          |                                                                1         |             
                                            __________________________________________________________________________|             
   Parathyroid Gland                       | M  M  +  +  M  M  +  M  M  M  +  +  +  M  +  +  M  M  +  +  +  +  M  +  +|             
                                            __________________________________________________________________________|             
   Pituitary Gland                         | +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Pars Distalis, Cyst                  |                                                                          |             
                                            __________________________________________________________________________|             
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
                                                             Page  57                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 2| 2| 7| 2| 2| 1| 4| 3| 7| 2| 7| 2| 5| 3| 7| 7| 6| 2| 1| 6| 3| 7| 1| 7| 3|             
                             DAY ON TEST   | 4| 2| 2| 3| 6| 9| 1| 5| 3| 4| 3| 7| 2| 1| 3| 3| 8| 7| 0| 5| 5| 3| 8| 3| 4|             
                                           | 0| 9| 1| 9| 0| 1| 4| 9| 3| 5| 6| 5| 7| 3| 6| 6| 7| 5| 2| 8| 9| 4| 9| 6| 6|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   B6C3F1 MICE MALE                        | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6|             
    1800 PPM                               | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
                                           | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM - cont                   |                                                                          |             
                                           |                                                                          |             
      Follicular Cell, Hyperplasia         |                                              1  1                        |             
 _____________________________________________________________________________________________________________________|             
 GENERAL BODY SYSTEM                       |                                                                          |             
                                           |                                                                          |             
    None                                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 GENITAL SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Coagulating Gland                       |                                                                   +      |             
                                            __________________________________________________________________________|             
   Epididymis                              | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Inflammation                         |                                                                          |             
                                            __________________________________________________________________________|             
   Penis                                   | +  +     +  +  +     +     +     +     +           +  +     +     +     +|             
      Congestion                           |    4                                                                     |             
      Inflammation, Suppurative            | 2        4                 1     3     1                                2|             
                                            __________________________________________________________________________|             
   Preputial Gland                         | +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
      Cyst                                 |                                              2                           |             
      Inflammation                         |                         3     2     2     4  2                           |             
                                            __________________________________________________________________________|             
   Prostate                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  M|             
      Inflammation, Suppurative            |    3  3  3  2  2     1     3     2  2  2           2  3                  |             
                                            __________________________________________________________________________|             
   Seminal Vesicle                         | +  A  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +  +  A  +  A|             
      Inflammation, Suppurative            |                                        4                                 |             
                                            __________________________________________________________________________|             
   Testes                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Atrophy                              |                                                          1               |             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hyperplasia                          |       3  2  4  2  3                    3           4  4                  |             
                                            __________________________________________________________________________|             
   Lymph Node                              |             +  +                 +  +              +                     |             
      Iliac, Hyperplasia                   |             3  2                 2  3              3                     |             
                                            __________________________________________________________________________|             
   Lymph Node, Bronchial                   | +  M  M  M  M  M  +  M  +  +  +  M  +  M  +  M  +  M  M  +  +  M  +  M  +|             
                                            __________________________________________________________________________|             
   Lymph Node, Mandibular                  | M  M  I  +  M  +  +  +  +  +  M  M  +  M  M  +  +  M  M  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Lymph Node, Mesenteric                  | +  M  +  M  M  +  +  +  +  M  +  +  M  +  +  +  +  +  M  +  +  +  +  +  A|             
      Hyperplasia                          |                                                                          |             
                                            __________________________________________________________________________|             
   Lymph Node, Mediastinal                 | M  +  +  M  +  +  +  +  +  M  +  M  +  M  +  +  M  +  M  +  M  M  +  +  +|             
                                            __________________________________________________________________________|             
   Spleen                                  | +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Atrophy                              |                                                                          |             
      Hematopoietic Cell Proliferation     | 3     2  2  4  2  2                 2  2           3  3  2     3  2  2   |             
                                            __________________________________________________________________________|             
   Thymus                                  | +  M  +  M  +  +  M  +  +  +  +  +  M  M  I  +  +  +  +  M  +  +  M  M  +|             
      Atrophy                              |             2  2           1     2                 2  2        3         |             
 _____________________________________________________________________________________________________________________|             
 INTEGUMENTARY SYSTEM                      |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Mammary Gland                           | M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M|             
                                            __________________________________________________________________________|             
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Prepuce, Inflammation, Suppurative   | 4  1  4  2  3  4  4        4        4                 1        2  4      |             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM                    |                                                                          |             
                                           |                                                                          |             
 _____________________________________________________________________________________________________________________|             
                                                             Page  58                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 2| 2| 7| 2| 2| 1| 4| 3| 7| 2| 7| 2| 5| 3| 7| 7| 6| 2| 1| 6| 3| 7| 1| 7| 3|             
                             DAY ON TEST   | 4| 2| 2| 3| 6| 9| 1| 5| 3| 4| 3| 7| 2| 1| 3| 3| 8| 7| 0| 5| 5| 3| 8| 3| 4|             
                                           | 0| 9| 1| 9| 0| 1| 4| 9| 3| 5| 6| 5| 7| 3| 6| 6| 7| 5| 2| 8| 9| 4| 9| 6| 6|             
 _____________________________________________________________________________________________________________________|             
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
   B6C3F1 MICE MALE                        | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|             
                               ANIMAL ID   | 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6|             
    1800 PPM                               | 0| 0| 0| 0| 0| 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2| 2| 2| 2| 2| 2|             
                                           | 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5|             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM - cont             |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Fibrous Osteodystrophy               |                                           1                              |             
 _____________________________________________________________________________________________________________________|             
 NERVOUS SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 RESPIRATORY SYSTEM                        |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Larynx                                  | +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                            __________________________________________________________________________|             
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Infiltration Cellular, Histiocyte    |                                                                          |             
      Thrombosis                           |                            2                                             |             
      Alveolar Epithelium, Hyperplasia     |                                                                          |             
                                            __________________________________________________________________________|             
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Inflammation, Suppurative            |                                              1  1              1         |             
      Nasolacrimal Duct, Inflammation,     |                                                                          |             
           Suppurative                     |                                                          2     1         |             
      Olfactory Epithelium, Atrophy, Focal |                                                                          |             
                                            __________________________________________________________________________|             
   Trachea                                 | +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 SPECIAL SENSES SYSTEM                     |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Eye                                     |                                                                          |             
                                            __________________________________________________________________________|             
   Harderian Gland                         |                                                          +               |             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM                            |                                                                          |             
                                           |                                                                          |             
                                            __________________________________________________________________________|             
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Hydronephrosis                       |          3     2           2        1  2           1  2  2              2|             
      Inflammation, Suppurative            |    1     3  4  2  3        2     1  1  3           3  3  3               |             
      Metaplasia, Osseous                  |                                           1                              |             
      Nephropathy                          |                               1              1                 1     1   |             
      Cortex, Cyst                         |                                                                          |             
      Pelvis, Necrosis                     |          3                 2                                             |             
      Renal Tubule, Hypertrophy            |                      1                                                   |             
      Renal Tubule, Necrosis               |                2                    1                                    |             
                                            __________________________________________________________________________|             
   Urethra                                 |    +     +  +  +           +     +     +           +  +                 +|             
      Inflammation, Suppurative            |    1     4  2  2           2     3     2           2  4                 1|             
      Necrosis                             |          4     2                                      4                 2|             
                                            __________________________________________________________________________|             
   Urinary Bladder                         | +  A  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +|             
      Calculus Gross Observation           | X                                   X                                    |             
      Calculus Micro Observation Only      |             X                                      X                     |             
      Inflammation, Suppurative            |       4  3  3  4  3        2        3  3           3  1  2               |             
      Transitional Epithelium, Hyperplasia |       2                                                  3               |             
 _____________________________________________________________________________________________________________________|             
                                                             Page  59                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 3| 7| 4| 7| 3| 7| 7| 6| 1| 7| 7| 7| 3| 0| 2| 3| 7| 5| 3| 0| 3| 6| 3| 3| 2|            |
                             DAY ON TEST   | 5| 1| 5| 3| 5| 3| 3| 7| 9| 0| 3| 3| 8| 9| 7| 2| 3| 5| 5| 0| 3| 3| 5| 4| 6|            |
                                           | 9| 5| 2| 4| 9| 6| 6| 0| 0| 6| 3| 4| 6| 9| 3| 1| 3| 4| 9| 7| 5| 9| 9| 9| 5|      T (*) |
 _____________________________________________________________________________________________________________________|            |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      O     |
   B6C3F1 MICE MALE                        | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      T     |
                               ANIMAL ID   | 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6|      A     |
    1800 PPM                               | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|      L     |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 ALIMENTARY SYSTEM                         |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Esophagus                               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Gallbladder                             | +  +  A  +  +  +  +  M  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +|  38        |
      Epithelium, Hyperplasia              |                                                                          |      1  1.0|
                                            __________________________________________________________________________|____________|
   Intestine Large, Colon                  | +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +|  45        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +|  43        |
                                            __________________________________________________________________________|____________|
   Intestine Large, Cecum                  | +  +  A  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +|  40        |
      Muscularis, Hyperplasia              |                                                                          |      1  1.0|
                                            __________________________________________________________________________|____________|
   Intestine Small, Duodenum               | +  +  A  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +|  40        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Jejunum                | +  +  A  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +|  37        |
                                            __________________________________________________________________________|____________|
   Intestine Small, Ileum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  A  +  +  +  +  +  +  +  +  +  +  +|  40        |
                                            __________________________________________________________________________|____________|
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Angiectasis                          |                                                                          |      1  1.0|
      Clear Cell Focus                     |          X                                                               |      2     |
      Eosinophilic Focus                   |                   X        X     X                                       |      5     |
      Necrosis                             |             1                                                            |      4  1.3|
                                            __________________________________________________________________________|____________|
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
      Atrophy                              |                                           1                              |      1  1.0|
      Hypertrophy                          |                                     1                                    |      1  1.0|
                                            __________________________________________________________________________|____________|
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
                                            __________________________________________________________________________|____________|
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Ulcer                                |                                                                          |      1  2.0|
      Epithelium, Hyperplasia              |       2                                                                  |      1  2.0|
                                            __________________________________________________________________________|____________|
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
      Degeneration, Hyaline                |                                                                          |      1  2.0|
      Erosion                              |                                                          2               |      3  2.7|
      Inflammation, Suppurative            |                                                                          |      2  2.0|
 _____________________________________________________________________________________________________________________|            |
 CARDIOVASCULAR SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Cardiomyopathy                       |    1     1     1     1     1  1  1              1                        |     14  1.0|
 _____________________________________________________________________________________________________________________|            |
 ENDOCRINE SYSTEM                          |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hyperplasia                          |                                                                2         |      2  2.0|
      Hypertrophy                          |    2  2              1     1  1  3                             2         |     10  1.6|
      Capsule, Hyperplasia                 |                               3                                          |      1  3.0|
                                            __________________________________________________________________________|____________|
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hyperplasia                          |                                                                          |      1  1.0|
                                            __________________________________________________________________________|____________|
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  60                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 3| 7| 4| 7| 3| 7| 7| 6| 1| 7| 7| 7| 3| 0| 2| 3| 7| 5| 3| 0| 3| 6| 3| 3| 2|            |
                             DAY ON TEST   | 5| 1| 5| 3| 5| 3| 3| 7| 9| 0| 3| 3| 8| 9| 7| 2| 3| 5| 5| 0| 3| 3| 5| 4| 6|            |
                                           | 9| 5| 2| 4| 9| 6| 6| 0| 0| 6| 3| 4| 6| 9| 3| 1| 3| 4| 9| 7| 5| 9| 9| 9| 5|      T (*) |
 _____________________________________________________________________________________________________________________|            |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      O     |
   B6C3F1 MICE MALE                        | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      T     |
                               ANIMAL ID   | 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6|      A     |
    1800 PPM                               | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|      L     |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 ENDOCRINE SYSTEM - cont                   |                                                                          |            |
                                           |                                                                          |            |
      Hyperplasia                          |                      1                                                   |      2  1.0|
                                            __________________________________________________________________________|____________|
   Parathyroid Gland                       | M  I  M  +  +  +  M  +  +  M  +  +  +  M  M  +  +  M  +  M  +  +  +  +  +|  30        |
                                            __________________________________________________________________________|____________|
   Pituitary Gland                         | +  +  I  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +|  47        |
      Pars Distalis, Cyst                  |          1                                                               |      1  1.0|
                                            __________________________________________________________________________|____________|
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +|  49        |
      Follicular Cell, Hyperplasia         |                                  2                                       |      3  1.3|
 _____________________________________________________________________________________________________________________|            |
 GENERAL BODY SYSTEM                       |                                                                          |            |
                                           |                                                                          |            |
    None                                   |                                                                          |            |
 _____________________________________________________________________________________________________________________|            |
 GENITAL SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Coagulating Gland                       |                                                                          |   1        |
                                            __________________________________________________________________________|____________|
   Epididymis                              | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Inflammation                         |          1                                                               |      1  1.0|
                                            __________________________________________________________________________|____________|
   Penis                                   | +                       +  +        +  +  +  +        +  +  +     +  +  +|  27        |
      Congestion                           |                                                                          |      1  4.0|
      Inflammation, Suppurative            |                            1              3  4                           |      9  2.3|
                                            __________________________________________________________________________|____________|
   Preputial Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
      Cyst                                 |                                                                          |      1  2.0|
      Inflammation                         |       1           2        3     4                                       |      9  2.6|
                                            __________________________________________________________________________|____________|
   Prostate                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +|  47        |
      Inflammation, Suppurative            |       2     1                                                            |     14  2.2|
                                            __________________________________________________________________________|____________|
   Seminal Vesicle                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  46        |
      Inflammation, Suppurative            |                                                                          |      1  4.0|
                                            __________________________________________________________________________|____________|
   Testes                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Atrophy                              |    1                                                                     |      2  1.0|
 _____________________________________________________________________________________________________________________|            |
 HEMATOPOIETIC SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hyperplasia                          | 3                       2  1     2  2  2                                 |     14  2.6|
                                            __________________________________________________________________________|____________|
   Lymph Node                              |                                                                          |   5        |
      Iliac, Hyperplasia                   |                                                                          |      5  2.6|
                                            __________________________________________________________________________|____________|
   Lymph Node, Bronchial                   | +  M  +  +  +  M  +  +  M  +  M  +  +  M  M  +  +  +  M  M  M  M  +  +  M|  26        |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mandibular                  | +  +  +  M  +  M  +  +  M  +  +  +  +  +  +  M  +  M  +  +  +  +  +  +  +|  35        |
                                            __________________________________________________________________________|____________|
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +|  41        |
      Hyperplasia                          |                                                                         2|      1  2.0|
                                            __________________________________________________________________________|____________|
   Lymph Node, Mediastinal                 | M  +  +  M  M  +  +  +  +  +  +  M  +  +  +  +  +  +  M  M  M  +  +  M  M|  32        |
                                            __________________________________________________________________________|____________|
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  49        |
      Atrophy                              |                                                          4               |      1  4.0|
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  61                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 3| 7| 4| 7| 3| 7| 7| 6| 1| 7| 7| 7| 3| 0| 2| 3| 7| 5| 3| 0| 3| 6| 3| 3| 2|            |
                             DAY ON TEST   | 5| 1| 5| 3| 5| 3| 3| 7| 9| 0| 3| 3| 8| 9| 7| 2| 3| 5| 5| 0| 3| 3| 5| 4| 6|            |
                                           | 9| 5| 2| 4| 9| 6| 6| 0| 0| 6| 3| 4| 6| 9| 3| 1| 3| 4| 9| 7| 5| 9| 9| 9| 5|      T (*) |
 _____________________________________________________________________________________________________________________|            |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      O     |
   B6C3F1 MICE MALE                        | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      T     |
                               ANIMAL ID   | 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6|      A     |
    1800 PPM                               | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|      L     |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 HEMATOPOIETIC SYSTEM - cont               |                                                                          |            |
                                           |                                                                          |            |
      Hematopoietic Cell Proliferation     | 2                       2              2  2                              |     18  2.3|
                                            __________________________________________________________________________|____________|
   Thymus                                  | +  +  M  +  +  +  +  +  M  M  +  +  +  +  M  +  +  +  +  +  +  +  I  +  +|  36        |
      Atrophy                              |                                        4                 2               |      9  2.2|
 _____________________________________________________________________________________________________________________|            |
 INTEGUMENTARY SYSTEM                      |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Mammary Gland                           | M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M  M|            |
                                            __________________________________________________________________________|____________|
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Prepuce, Inflammation, Suppurative   |                   4        4                 4     4        4        1   |     18  3.2|
 _____________________________________________________________________________________________________________________|            |
 MUSCULOSKELETAL SYSTEM                    |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Fibrous Osteodystrophy               |                                                                          |      1  1.0|
 _____________________________________________________________________________________________________________________|            |
 NERVOUS SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
 _____________________________________________________________________________________________________________________|            |
 RESPIRATORY SYSTEM                        |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +|  48        |
                                            __________________________________________________________________________|____________|
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Infiltration Cellular, Histiocyte    |    4                                                                     |      1  4.0|
      Thrombosis                           |                                                                          |      1  2.0|
      Alveolar Epithelium, Hyperplasia     |                            3                                             |      1  3.0|
                                            __________________________________________________________________________|____________|
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Inflammation, Suppurative            |                                  1                                       |      4  1.0|
      Nasolacrimal Duct, Inflammation,     |                                                                          |            |
           Suppurative                     |                                                                          |      2  1.5|
      Olfactory Epithelium, Atrophy, Focal |          1                                                               |      1  1.0|
                                            __________________________________________________________________________|____________|
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +|  48        |
 _____________________________________________________________________________________________________________________|            |
 SPECIAL SENSES SYSTEM                     |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Eye                                     |                               +                                          |   1        |
                                            __________________________________________________________________________|____________|
   Harderian Gland                         |                         +     +                                          |   3        |
 _____________________________________________________________________________________________________________________|            |
 URINARY SYSTEM                            |                                                                          |            |
                                           |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  50        |
      Hydronephrosis                       | 2     2                 2           1  1  1                 1        3  3|     18  1.8|
      Inflammation, Suppurative            | 3     2                 4           1  4                             2   |     18  2.5|
      Metaplasia, Osseous                  |    1                             1                                       |      3  1.0|
      Nephropathy                          |          1     1  2  1     2  1  1              1  3           1         |     14  1.3|
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  62                                                               
NTP Experiment-Test: 05181-04                  NONNEOPLASTIC LESIONS BY INDIVIDUAL ANIMAL                         Report: PEIRPT09  
Study Type: CHRONIC                                          TETRAHYDROFURAN                                      Date: 02/21/96    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 12:49:30    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 3| 7| 4| 7| 3| 7| 7| 6| 1| 7| 7| 7| 3| 0| 2| 3| 7| 5| 3| 0| 3| 6| 3| 3| 2|            |
                             DAY ON TEST   | 5| 1| 5| 3| 5| 3| 3| 7| 9| 0| 3| 3| 8| 9| 7| 2| 3| 5| 5| 0| 3| 3| 5| 4| 6|            |
                                           | 9| 5| 2| 4| 9| 6| 6| 0| 0| 6| 3| 4| 6| 9| 3| 1| 3| 4| 9| 7| 5| 9| 9| 9| 5|      T (*) |
 _____________________________________________________________________________________________________________________|            |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      O     |
   B6C3F1 MICE MALE                        | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|      T     |
                               ANIMAL ID   | 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6|      A     |
    1800 PPM                               | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4| 4| 4| 4| 4| 5|      L     |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|            |
 __________________________________________________________________________________________________________________________________ 
 URINARY SYSTEM - cont                     |                                                                          |            |
                                           |                                                                          |            |
      Cortex, Cyst                         |                      1                                                   |      1  1.0|
      Pelvis, Necrosis                     |                                                                         1|      3  2.0|
      Renal Tubule, Hypertrophy            |                                                                          |      1  1.0|
      Renal Tubule, Necrosis               |                                                                          |      2  1.5|
                                            __________________________________________________________________________|____________|
   Urethra                                 | +                       +                                +              +|  14        |
      Inflammation, Suppurative            | 1                                                                       3|     12  2.3|
      Necrosis                             |                                                                         3|      5  3.0|
                                            __________________________________________________________________________|____________|
   Urinary Bladder                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|  48        |
      Calculus Gross Observation           |                                                                      X   |      3     |
      Calculus Micro Observation Only      |                                                                          |      2     |
      Inflammation, Suppurative            | 4                       4           3  2                             1   |     16  2.8|
      Transitional Epithelium, Hyperplasia | 2                       2           4                                    |      5  2.6|
 __________________________________________________________________________________________________________________________________ 
  * : Total animals with tissue examined microscopically; total animals with lesion and mean severity grade                         
  + : Tissue examined microscopically                M : Missing tissue                        1-4 : Lesion qualified as:           
  X : Lesion present but not qualified               A : Autolysis precludes examination               1) Minimal  3) Moderate      
  I : Insufficient tissue                        BLANK : Not examined                                  2) Mild     4) Marked        
                                                             Page  63                                                               
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