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TDMS Study 05135-05 Pathology Tables

NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18




       Facility:  Battelle Northwest

       Chemical CAS #:  78-79-5

       Lock Date:  None

       Cage Range:  All

       Reasons For Removal:    All

       Removal Date Range:     All

       Treatment Groups:       Include All




































Note:  Animals arranged according to CID number

                                                              Page   1


NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 3| 3| 3| 1| 3| 1| 3| 3| 3| 1| 3| 3| 3| 3| 1| 1| 3| 3| 1| 1| 3| 1| 3| 3| 3|             
                             DAY ON TEST   | 6| 6| 6| 8| 6| 8| 6| 6| 6| 8| 6| 6| 6| 6| 8| 8| 6| 6| 8| 8| 6| 8| 6| 6| 6|             
                                           | 8| 8| 8| 6| 8| 6| 8| 8| 8| 6| 8| 8| 8| 8| 6| 6| 8| 8| 6| 6| 8| 6| 8| 8| 8|             
 __________________________________________|__________________________________________________________________________|             
                                           | 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|             
   FISCHER 344 RATS 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                               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Intestine Large, Colon                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Intestine Large, Cecum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Intestine Small, Duodenum               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Intestine Small, Jejunum                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Intestine Small, Ileum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Mesentery                               |                                  +                                       |             
                                           |__________________________________________________________________________|             
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Pharynx                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 CARDIOVASCULAR SYSTEM                     |                                                                          |             
                                           |__________________________________________________________________________|             
   Blood Vessel                            | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM                          |                                                                          |             
                                           |__________________________________________________________________________|             
 __________________________________________|__________________________________________________________________________|             
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page   2                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 3| 3| 3| 1| 3| 1| 3| 3| 3| 1| 3| 3| 3| 3| 1| 1| 3| 3| 1| 1| 3| 1| 3| 3| 3|             
                             DAY ON TEST   | 6| 6| 6| 8| 6| 8| 6| 6| 6| 8| 6| 6| 6| 6| 8| 8| 6| 6| 8| 8| 6| 8| 6| 6| 6|             
                                           | 8| 8| 8| 6| 8| 6| 8| 8| 8| 6| 8| 8| 8| 8| 6| 6| 8| 8| 6| 6| 8| 6| 8| 8| 8|             
 __________________________________________|__________________________________________________________________________|             
                                           | 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|             
   FISCHER 344 RATS 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                   |                                                                          |             
                                           |                                                                          |             
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Parathyroid Gland                       | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Pituitary Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Adenoma                              |                               X        X                          X      |             
                                           |__________________________________________________________________________|             
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 GENERAL BODY SYSTEM                       |                                                                          |             
    None                                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 GENITAL SYSTEM                            |                                                                          |             
                                           |__________________________________________________________________________|             
   Epididymis                              | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Preputial Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Prostate                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Seminal Vesicle                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Testes                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Interstitial Cell, Adenoma           | X                                X                                       |             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM                      |                                                                          |             
                                           |__________________________________________________________________________|             
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Lymph Node                              |                      +                                                   |             
                                           |__________________________________________________________________________|             
   Lymph Node, Bronchial                   | M  +  +  +  M  +  +  M  M  +  +  +  +  +  +  M  +  M  +  +  +  +  +  +  +|             
 __________________________________________|__________________________________________________________________________|             
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page   3                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 3| 3| 3| 1| 3| 1| 3| 3| 3| 1| 3| 3| 3| 3| 1| 1| 3| 3| 1| 1| 3| 1| 3| 3| 3|             
                             DAY ON TEST   | 6| 6| 6| 8| 6| 8| 6| 6| 6| 8| 6| 6| 6| 6| 8| 8| 6| 6| 8| 8| 6| 8| 6| 6| 6|             
                                           | 8| 8| 8| 6| 8| 6| 8| 8| 8| 6| 8| 8| 8| 8| 6| 6| 8| 8| 6| 6| 8| 6| 8| 8| 8|             
 __________________________________________|__________________________________________________________________________|             
                                           | 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|             
   FISCHER 344 RATS 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               |                                                                          |             
                                           |                                                                          |             
                                           |__________________________________________________________________________|             
   Lymph Node, Mandibular                  | +  +  +  +  +  M  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +|             
                                           |__________________________________________________________________________|             
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Lymph Node, Mediastinal                 | +  +  +  +  M  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +  +  +|             
                                           |__________________________________________________________________________|             
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Thymus                                  | +  +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  M  +  +  +  M  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 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|             
                                           |__________________________________________________________________________|             
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM                    |                                                                          |             
                                           |__________________________________________________________________________|             
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 NERVOUS SYSTEM                            |                                                                          |             
                                           |__________________________________________________________________________|             
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Peripheral Nerve                        | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Spinal Cord                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  M  +|             
 _____________________________________________________________________________________________________________________|             
 RESPIRATORY SYSTEM                        |                                                                          |             
                                           |__________________________________________________________________________|             
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Alveolar/Bronchiolar Adenoma         |                                        X                                 |             
                                           |__________________________________________________________________________|             
 __________________________________________|__________________________________________________________________________|             
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page   4                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 3| 3| 3| 1| 3| 1| 3| 3| 3| 1| 3| 3| 3| 3| 1| 1| 3| 3| 1| 1| 3| 1| 3| 3| 3|             
                             DAY ON TEST   | 6| 6| 6| 8| 6| 8| 6| 6| 6| 8| 6| 6| 6| 6| 8| 8| 6| 6| 8| 8| 6| 8| 6| 6| 6|             
                                           | 8| 8| 8| 6| 8| 6| 8| 8| 8| 6| 8| 8| 8| 8| 6| 6| 8| 8| 6| 6| 8| 6| 8| 8| 8|             
 __________________________________________|__________________________________________________________________________|             
                                           | 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|             
   FISCHER 344 RATS 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|             
 __________________________________________|__________________________________________________________________________|             
 RESPIRATORY SYSTEM - cont                 |                                                                          |             
                                           |                                                                          |             
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 SPECIAL SENSES SYSTEM                     |                                                                          |             
                                           |__________________________________________________________________________|             
   Eye                                     | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Harderian Gland                         |                   +     +                                      +         |             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM                            |                                                                          |             
                                           |__________________________________________________________________________|             
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Urinary Bladder                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 __________________________________________|__________________________________________________________________________|             
 SYSTEMIC LESIONS                          |                                                                          |             
                                            __________________________________________________________________________|             
   Multiple Organs                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 __________________________________________|__________________________________________________________________________|             
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page   5                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 3| 3| 3| 3| 3| 1| 3| 3| 3| 1| 3| 3| 3| 3| 3|                             |            |
                             DAY ON TEST   | 6| 6| 6| 6| 6| 8| 6| 6| 6| 8| 6| 6| 6| 6| 6|                             |            |
                                           | 8| 8| 8| 8| 8| 6| 8| 8| 8| 6| 8| 8| 8| 8| 8|                             |            |
 __________________________________________|__________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|                             |     O      |
   FISCHER 344 RATS MALE                   | 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|                             |     A      |
    CONTROL                                | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4|                             |     L      |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|                             |            |
 _____________________________________________________________________________________________________________________|____________|
 ALIMENTARY SYSTEM                         |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Esophagus                               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Intestine Large, Colon                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Intestine Large, Rectum                 | +  +  +  +  +  M  +  +  +  +  +  +  +  +  +                              |  39        |
                                           |__________________________________________________________________________|____________|
   Intestine Large, Cecum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Intestine Small, Duodenum               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Intestine Small, Jejunum                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Intestine Small, Ileum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Mesentery                               |                                                                          |   1        |
                                           |__________________________________________________________________________|____________|
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Pharynx                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
 _____________________________________________________________________________________________________________________|            |
 CARDIOVASCULAR SYSTEM                     |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Blood Vessel                            | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
 _____________________________________________________________________________________________________________________|____________|
                                                                                                                                    
                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  
                                                                                                                                    
                                                                                                                                    
                                                             Page   6                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 3| 3| 3| 3| 3| 1| 3| 3| 3| 1| 3| 3| 3| 3| 3|                             |            |
                             DAY ON TEST   | 6| 6| 6| 6| 6| 8| 6| 6| 6| 8| 6| 6| 6| 6| 6|                             |            |
                                           | 8| 8| 8| 8| 8| 6| 8| 8| 8| 6| 8| 8| 8| 8| 8|                             |            |
 __________________________________________|__________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|                             |     O      |
   FISCHER 344 RATS MALE                   | 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|                             |     A      |
    CONTROL                                | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4|                             |     L      |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|                             |            |
 _____________________________________________________________________________________________________________________|____________|
 CARDIOVASCULAR SYSTEM - cont              |                                                                          |            |
                                           |                                                                          |            |
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
 _____________________________________________________________________________________________________________________|            |
 ENDOCRINE SYSTEM                          |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Adrenal Medulla                         | +  +  M  +  +  +  +  +  +  +  +  +  +  +  +                              |  38        |
                                           |__________________________________________________________________________|____________|
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Parathyroid Gland                       | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Pituitary Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
      Adenoma                              |                   X           X     X                                    |          6 |
                                           |__________________________________________________________________________|____________|
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
 _____________________________________________________________________________________________________________________|            |
 GENERAL BODY SYSTEM                       |                                                                          |            |
    None                                   |                                                                          |            |
 _____________________________________________________________________________________________________________________|            |
 GENITAL SYSTEM                            |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Epididymis                              | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Preputial Gland                         | +  +  +  +  +  +  +  M  +  +  +  +  +  +  +                              |  39        |
                                           |__________________________________________________________________________|____________|
   Prostate                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Seminal Vesicle                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Testes                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
      Interstitial Cell, Adenoma           |                                           X                              |          3 |
 _____________________________________________________________________________________________________________________|____________|
                                                                                                                                    
                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  
                                                                                                                                    
                                                                                                                                    
                                                             Page   7                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 3| 3| 3| 3| 3| 1| 3| 3| 3| 1| 3| 3| 3| 3| 3|                             |            |
                             DAY ON TEST   | 6| 6| 6| 6| 6| 8| 6| 6| 6| 8| 6| 6| 6| 6| 6|                             |            |
                                           | 8| 8| 8| 8| 8| 6| 8| 8| 8| 6| 8| 8| 8| 8| 8|                             |            |
 __________________________________________|__________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|                             |     O      |
   FISCHER 344 RATS MALE                   | 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|                             |     A      |
    CONTROL                                | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4|                             |     L      |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|                             |            |
 _____________________________________________________________________________________________________________________|____________|
 HEMATOPOIETIC SYSTEM                      |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Lymph Node                              |                                                                          |   1        |
                                           |__________________________________________________________________________|____________|
   Lymph Node, Bronchial                   | +  M  +  +  M  +  +  +  +  +  +  +  +  +  +                              |  32        |
                                           |__________________________________________________________________________|____________|
   Lymph Node, Mandibular                  | +  +  +  +  +  +  +  M  +  +  +  +  +  M  +                              |  35        |
                                           |__________________________________________________________________________|____________|
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Lymph Node, Mediastinal                 | +  +  +  M  +  +  +  +  +  M  +  +  +  +  +                              |  35        |
                                           |__________________________________________________________________________|____________|
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Thymus                                  | +  +  +  M  +  M  +  +  +  +  +  +  +  +  +                              |  35        |
 _____________________________________________________________________________________________________________________|            |
 INTEGUMENTARY SYSTEM                      |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Mammary Gland                           | M  M  M  M  M  M  M  M  M  M  M  M  M  M  M                              |   3        |
                                           |__________________________________________________________________________|____________|
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
 _____________________________________________________________________________________________________________________|            |
 MUSCULOSKELETAL SYSTEM                    |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
 _____________________________________________________________________________________________________________________|            |
 NERVOUS SYSTEM                            |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Peripheral Nerve                        | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
 _____________________________________________________________________________________________________________________|____________|
                                                                                                                                    
                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  
                                                                                                                                    
                                                                                                                                    
                                                             Page   8                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 3| 3| 3| 3| 3| 1| 3| 3| 3| 1| 3| 3| 3| 3| 3|                             |            |
                             DAY ON TEST   | 6| 6| 6| 6| 6| 8| 6| 6| 6| 8| 6| 6| 6| 6| 6|                             |            |
                                           | 8| 8| 8| 8| 8| 6| 8| 8| 8| 6| 8| 8| 8| 8| 8|                             |            |
 __________________________________________|__________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|                             |     O      |
   FISCHER 344 RATS MALE                   | 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|                             |     A      |
    CONTROL                                | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4|                             |     L      |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|                             |            |
 _____________________________________________________________________________________________________________________|____________|
 NERVOUS SYSTEM - cont                     |                                                                          |            |
                                           |                                                                          |            |
   Spinal Cord                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  39        |
 _____________________________________________________________________________________________________________________|            |
 RESPIRATORY SYSTEM                        |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
      Alveolar/Bronchiolar Adenoma         |                                                                          |          1 |
                                           |__________________________________________________________________________|____________|
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
 _____________________________________________________________________________________________________________________|            |
 SPECIAL SENSES SYSTEM                     |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Eye                                     | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Harderian Gland                         |                +              +                                          |   5        |
 _____________________________________________________________________________________________________________________|            |
 URINARY SYSTEM                            |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Urinary Bladder                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
 __________________________________________________________________________________________________________________________________ 
 SYSTEMIC LESIONS                          |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Multiple Organs                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
 __________________________________________________________________________________________________________________________________ 
                                                                                                                                    
                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page   9                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 3| 3| 1| 3| 1| 3| 3| 3| 3| 3| 3| 3| 1| 3| 1| 3| 3| 1| 3| 1| 3| 1| 1| 3| 3|             
                             DAY ON TEST   | 6| 6| 8| 6| 8| 6| 6| 6| 6| 6| 6| 6| 8| 6| 8| 6| 6| 8| 6| 8| 6| 8| 8| 6| 6|             
                                           | 8| 8| 6| 8| 6| 8| 8| 8| 8| 8| 8| 8| 6| 8| 6| 8| 8| 6| 8| 6| 8| 6| 6| 8| 8|             
 __________________________________________|__________________________________________________________________________|             
                                           | 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|             
   FISCHER 344 RATS 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|             
    70 PPM                                 | 4| 4| 4| 4| 4| 4| 4| 4| 4| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 6| 6| 6| 6| 6| 6|             
                                           | 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                               |       +     +                       +     +        +     +     +  +      |             
                                           |__________________________________________________________________________|             
   Intestine Large, Colon                  |       +     +                       +     +        +     +     +  +      |             
                                           |__________________________________________________________________________|             
   Intestine Large, Rectum                 |       +     +                       +     +        +     +     +  +      |             
                                           |__________________________________________________________________________|             
   Intestine Large, Cecum                  |       +     +                       +     +        +     +     +  +      |             
                                           |__________________________________________________________________________|             
   Intestine Small, Duodenum               |       +     +                       +     +        +     +     +  +      |             
                                           |__________________________________________________________________________|             
   Intestine Small, Jejunum                |       +     +                       +     +        +     +     +  +      |             
                                           |__________________________________________________________________________|             
   Intestine Small, Ileum                  |       +     +                       +     +        +     +     +  +      |             
                                           |__________________________________________________________________________|             
   Liver                                   |       +     +  +                    +  +  +        +  +  +     +  +  +   |             
                                           |__________________________________________________________________________|             
   Mesentery                               |                                                             +        +   |             
                                           |__________________________________________________________________________|             
   Pancreas                                |       +     +                       +     +        +     +     +  +      |             
                                           |__________________________________________________________________________|             
   Pharynx                                 |       +     +                       +     +        +     +     +  +      |             
                                           |__________________________________________________________________________|             
   Salivary Glands                         |       +     +                       +     +        +     +     +  +      |             
                                           |__________________________________________________________________________|             
   Stomach, Forestomach                    |       +     +                       +     +        +     +     +  +      |             
                                           |__________________________________________________________________________|             
   Stomach, Glandular                      |       +     +                       +     +        +     +     +  +      |             
 _____________________________________________________________________________________________________________________|             
 CARDIOVASCULAR SYSTEM                     |                                                                          |             
                                           |__________________________________________________________________________|             
   Blood Vessel                            |       +     +                       +     +        +     +     +  +      |             
                                           |__________________________________________________________________________|             
   Heart                                   |       +     +                       +     +        +     +     +  +      |             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM                          |                                                                          |             
                                           |__________________________________________________________________________|             
 __________________________________________|__________________________________________________________________________|             
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page  10                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 3| 3| 1| 3| 1| 3| 3| 3| 3| 3| 3| 3| 1| 3| 1| 3| 3| 1| 3| 1| 3| 1| 1| 3| 3|             
                             DAY ON TEST   | 6| 6| 8| 6| 8| 6| 6| 6| 6| 6| 6| 6| 8| 6| 8| 6| 6| 8| 6| 8| 6| 8| 8| 6| 6|             
                                           | 8| 8| 6| 8| 6| 8| 8| 8| 8| 8| 8| 8| 6| 8| 6| 8| 8| 6| 8| 6| 8| 6| 6| 8| 8|             
 __________________________________________|__________________________________________________________________________|             
                                           | 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|             
   FISCHER 344 RATS 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|             
    70 PPM                                 | 4| 4| 4| 4| 4| 4| 4| 4| 4| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 6| 6| 6| 6| 6| 6|             
                                           | 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                   |                                                                          |             
                                           |                                                                          |             
   Adrenal Cortex                          |       +     +                       +     +        +     +     +  +      |             
                                           |__________________________________________________________________________|             
   Adrenal Medulla                         |       +     +                       +     +        +     +     +  +      |             
                                           |__________________________________________________________________________|             
   Islets, Pancreatic                      |       +     +                       +     +        +     +     +  +      |             
                                           |__________________________________________________________________________|             
   Parathyroid Gland                       |       +     +                       +     +        +     +     +  +      |             
                                           |__________________________________________________________________________|             
   Pituitary Gland                         |       +     +           +  +     +  +     +        +     +  +  +  +  +  +|             
      Adenoma                              |                            X     X                          X        X  X|             
                                           |__________________________________________________________________________|             
   Thyroid Gland                           |       +     +                       +     +        +     +     +  +      |             
 _____________________________________________________________________________________________________________________|             
 GENERAL BODY SYSTEM                       |                                                                          |             
    None                                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 GENITAL SYSTEM                            |                                                                          |             
                                           |__________________________________________________________________________|             
   Epididymis                              |       +     +                       +     +        +     +     +  +      |             
                                           |__________________________________________________________________________|             
   Preputial Gland                         |       +     +                       +     +        +     +     +  +      |             
                                           |__________________________________________________________________________|             
   Prostate                                |       +     +                       +     +        +     +     +  +      |             
                                           |__________________________________________________________________________|             
   Seminal Vesicle                         |       +     +                       +     +        +     +     +  +      |             
                                           |__________________________________________________________________________|             
   Testes                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                               X                 X                        |             
      Interstitial Cell, Adenoma           |                         X                    X                           |             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM                      |                                                                          |             
                                           |__________________________________________________________________________|             
   Bone Marrow                             |       +     +                       +     +        +     +     +  +      |             
                                           |__________________________________________________________________________|             
   Lymph Node                              |                                                                +         |             
                                           |__________________________________________________________________________|             
 __________________________________________|__________________________________________________________________________|             
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page  11                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 3| 3| 1| 3| 1| 3| 3| 3| 3| 3| 3| 3| 1| 3| 1| 3| 3| 1| 3| 1| 3| 1| 1| 3| 3|             
                             DAY ON TEST   | 6| 6| 8| 6| 8| 6| 6| 6| 6| 6| 6| 6| 8| 6| 8| 6| 6| 8| 6| 8| 6| 8| 8| 6| 6|             
                                           | 8| 8| 6| 8| 6| 8| 8| 8| 8| 8| 8| 8| 6| 8| 6| 8| 8| 6| 8| 6| 8| 6| 6| 8| 8|             
 __________________________________________|__________________________________________________________________________|             
                                           | 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|             
   FISCHER 344 RATS 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|             
    70 PPM                                 | 4| 4| 4| 4| 4| 4| 4| 4| 4| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 6| 6| 6| 6| 6| 6|             
                                           | 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, Bronchial                   |       +     +                       +     +        +     +     +  +      |             
                                           |__________________________________________________________________________|             
   Lymph Node, Mandibular                  |       +     +                       +     +        +     +     +  +      |             
                                           |__________________________________________________________________________|             
   Lymph Node, Mesenteric                  |       +     +                       +     +        +     +     +  +      |             
                                           |__________________________________________________________________________|             
   Lymph Node, Mediastinal                 |       +     +        +  +           +     +        +     +  +  +  +      |             
                                           |__________________________________________________________________________|             
   Spleen                                  |       +     +           +     +     +     +     +  +     +     +  +      |             
      Leukemia Mononuclear                 |                               X                 X                        |             
                                           |__________________________________________________________________________|             
   Thymus                                  |       +     +                       +     +        +     +     +  +      |             
 _____________________________________________________________________________________________________________________|             
 INTEGUMENTARY SYSTEM                      |                                                                          |             
                                           |__________________________________________________________________________|             
   Mammary Gland                           |       +     +                       +     +        +     +     +  +      |             
                                           |__________________________________________________________________________|             
   Skin                                    |       +     +                       +     +        +     +     +  +      |             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM                    |                                                                          |             
                                           |__________________________________________________________________________|             
   Bone                                    |       +     +                       +     +        +     +     +  +      |             
 _____________________________________________________________________________________________________________________|             
 NERVOUS SYSTEM                            |                                                                          |             
                                           |__________________________________________________________________________|             
   Brain                                   |       +     +           +           +     +        +     +     +  +      |             
                                           |__________________________________________________________________________|             
   Peripheral Nerve                        |       +     +                       +     +        +     +     +  +      |             
                                           |__________________________________________________________________________|             
   Spinal Cord                             |       +     +                       +     +        +     +     +  +      |             
 _____________________________________________________________________________________________________________________|             
 RESPIRATORY SYSTEM                        |                                                                          |             
                                           |__________________________________________________________________________|             
   Larynx                                  |       +     +                       +     +        +     +     +  +      |             
                                           |__________________________________________________________________________|             
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 __________________________________________|__________________________________________________________________________|             
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page  12                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 3| 3| 1| 3| 1| 3| 3| 3| 3| 3| 3| 3| 1| 3| 1| 3| 3| 1| 3| 1| 3| 1| 1| 3| 3|             
                             DAY ON TEST   | 6| 6| 8| 6| 8| 6| 6| 6| 6| 6| 6| 6| 8| 6| 8| 6| 6| 8| 6| 8| 6| 8| 8| 6| 6|             
                                           | 8| 8| 6| 8| 6| 8| 8| 8| 8| 8| 8| 8| 6| 8| 6| 8| 8| 6| 8| 6| 8| 6| 6| 8| 8|             
 __________________________________________|__________________________________________________________________________|             
                                           | 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|             
   FISCHER 344 RATS 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|             
    70 PPM                                 | 4| 4| 4| 4| 4| 4| 4| 4| 4| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 6| 6| 6| 6| 6| 6|             
                                           | 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                 |                                                                          |             
                                           |                                                                          |             
      Alveolar/Bronchiolar Adenoma         |                                                                          |             
                                           |__________________________________________________________________________|             
   Nose                                    |       +     +                       +     +        +     +     +  +      |             
                                           |__________________________________________________________________________|             
   Trachea                                 |       +     +                       +     +        +     +     +  +      |             
 _____________________________________________________________________________________________________________________|             
 SPECIAL SENSES SYSTEM                     |                                                                          |             
                                           |__________________________________________________________________________|             
   Eye                                     |       +     +                       +     +        +     +     +  +      |             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM                            |                                                                          |             
                                           |__________________________________________________________________________|             
   Kidney                                  |       +     +                       +     +        +     +     +  +      |             
                                           |__________________________________________________________________________|             
   Urinary Bladder                         |       +     +                       +     +        +     +     +  +      |             
 __________________________________________|__________________________________________________________________________|             
 SYSTEMIC LESIONS                          |                                                                          |             
                                            __________________________________________________________________________|             
   Multiple Organs                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Leukemia Mononuclear                 |                               X                 X                        |             
 __________________________________________|__________________________________________________________________________|             
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page  13                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 1| 3| 3| 3| 3| 3| 1| 3| 3| 3| 3| 3| 3| 3| 3|                             |            |
                             DAY ON TEST   | 8| 6| 6| 6| 6| 6| 8| 6| 6| 6| 6| 6| 6| 6| 6|                             |            |
                                           | 6| 8| 8| 8| 8| 8| 6| 8| 8| 8| 8| 8| 8| 8| 8|                             |            |
 __________________________________________|__________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|                             |     O      |
   FISCHER 344 RATS MALE                   | 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|                             |     A      |
    70 PPM                                 | 6| 6| 6| 6| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 8|                             |     L      |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|                             |            |
 _____________________________________________________________________________________________________________________|____________|
 ALIMENTARY SYSTEM                         |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Esophagus                               | +                 +                                                      |  10        |
                                           |__________________________________________________________________________|____________|
   Intestine Large, Colon                  | +                 +                                                      |  10        |
                                           |__________________________________________________________________________|____________|
   Intestine Large, Rectum                 | +                 +                                                      |  10        |
                                           |__________________________________________________________________________|____________|
   Intestine Large, Cecum                  | +                 +                                                      |  10        |
                                           |__________________________________________________________________________|____________|
   Intestine Small, Duodenum               | +                 +                                                      |  10        |
                                           |__________________________________________________________________________|____________|
   Intestine Small, Jejunum                | +                 +                                                      |  10        |
                                           |__________________________________________________________________________|____________|
   Intestine Small, Ileum                  | +                 +                                                      |  10        |
                                           |__________________________________________________________________________|____________|
   Liver                                   | +                 +                       +                              |  15        |
                                           |__________________________________________________________________________|____________|
   Mesentery                               |                                                                          |   2        |
                                           |__________________________________________________________________________|____________|
   Pancreas                                | +                 +                                                      |  10        |
                                           |__________________________________________________________________________|____________|
   Pharynx                                 | +                 +                                                      |  10        |
                                           |__________________________________________________________________________|____________|
   Salivary Glands                         | +                 +                                                      |  10        |
                                           |__________________________________________________________________________|____________|
   Stomach, Forestomach                    | +                 +                                                      |  10        |
                                           |__________________________________________________________________________|____________|
   Stomach, Glandular                      | +                 +                                                      |  10        |
 _____________________________________________________________________________________________________________________|            |
 CARDIOVASCULAR SYSTEM                     |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Blood Vessel                            | +                 +                                                      |  10        |
                                           |__________________________________________________________________________|____________|
 _____________________________________________________________________________________________________________________|____________|
                                                                                                                                    
                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  
                                                                                                                                    
                                                                                                                                    
                                                             Page  14                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 1| 3| 3| 3| 3| 3| 1| 3| 3| 3| 3| 3| 3| 3| 3|                             |            |
                             DAY ON TEST   | 8| 6| 6| 6| 6| 6| 8| 6| 6| 6| 6| 6| 6| 6| 6|                             |            |
                                           | 6| 8| 8| 8| 8| 8| 6| 8| 8| 8| 8| 8| 8| 8| 8|                             |            |
 __________________________________________|__________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|                             |     O      |
   FISCHER 344 RATS MALE                   | 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|                             |     A      |
    70 PPM                                 | 6| 6| 6| 6| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 8|                             |     L      |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|                             |            |
 _____________________________________________________________________________________________________________________|____________|
 CARDIOVASCULAR SYSTEM - cont              |                                                                          |            |
                                           |                                                                          |            |
   Heart                                   | +                 +                                                      |  10        |
 _____________________________________________________________________________________________________________________|            |
 ENDOCRINE SYSTEM                          |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Adrenal Cortex                          | +                 +                                                      |  10        |
                                           |__________________________________________________________________________|____________|
   Adrenal Medulla                         | +                 +                                                      |  10        |
                                           |__________________________________________________________________________|____________|
   Islets, Pancreatic                      | +                 +                                                      |  10        |
                                           |__________________________________________________________________________|____________|
   Parathyroid Gland                       | +                 +                                                      |  10        |
                                           |__________________________________________________________________________|____________|
   Pituitary Gland                         | +  +              +           +                                          |  18        |
      Adenoma                              |    X                          X                                          |          7 |
                                           |__________________________________________________________________________|____________|
   Thyroid Gland                           | +                 +                                                      |  10        |
 _____________________________________________________________________________________________________________________|            |
 GENERAL BODY SYSTEM                       |                                                                          |            |
    None                                   |                                                                          |            |
 _____________________________________________________________________________________________________________________|            |
 GENITAL SYSTEM                            |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Epididymis                              | +                 +                                                      |  10        |
                                           |__________________________________________________________________________|____________|
   Preputial Gland                         | +                 +                                                      |  10        |
                                           |__________________________________________________________________________|____________|
   Prostate                                | +                 +                                                      |  10        |
                                           |__________________________________________________________________________|____________|
   Seminal Vesicle                         | +                 +                                                      |  10        |
                                           |__________________________________________________________________________|____________|
   Testes                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
      Leukemia Mononuclear                 |                                                                          |          2 |
 _____________________________________________________________________________________________________________________|____________|
                                                                                                                                    
                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  
                                                                                                                                    
                                                                                                                                    
                                                             Page  15                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 1| 3| 3| 3| 3| 3| 1| 3| 3| 3| 3| 3| 3| 3| 3|                             |            |
                             DAY ON TEST   | 8| 6| 6| 6| 6| 6| 8| 6| 6| 6| 6| 6| 6| 6| 6|                             |            |
                                           | 6| 8| 8| 8| 8| 8| 6| 8| 8| 8| 8| 8| 8| 8| 8|                             |            |
 __________________________________________|__________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|                             |     O      |
   FISCHER 344 RATS MALE                   | 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|                             |     A      |
    70 PPM                                 | 6| 6| 6| 6| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 8|                             |     L      |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|                             |            |
 _____________________________________________________________________________________________________________________|____________|
 GENITAL SYSTEM - cont                     |                                                                          |            |
                                           |                                                                          |            |
      Interstitial Cell, Adenoma           |       X                                                                  |          3 |
 _____________________________________________________________________________________________________________________|            |
 HEMATOPOIETIC SYSTEM                      |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Bone Marrow                             | +                 +                                                      |  10        |
                                           |__________________________________________________________________________|____________|
   Lymph Node                              |                   +                                                      |   2        |
                                           |__________________________________________________________________________|____________|
   Lymph Node, Bronchial                   | +                 +                                                      |  10        |
                                           |__________________________________________________________________________|____________|
   Lymph Node, Mandibular                  | +                 +                                                      |  10        |
                                           |__________________________________________________________________________|____________|
   Lymph Node, Mesenteric                  | +                 +                                                      |  10        |
                                           |__________________________________________________________________________|____________|
   Lymph Node, Mediastinal                 | +                 +           +           +                              |  15        |
                                           |__________________________________________________________________________|____________|
   Spleen                                  | +                 +                                                      |  13        |
      Leukemia Mononuclear                 |                                                                          |          2 |
                                           |__________________________________________________________________________|____________|
   Thymus                                  | +                 +                                                      |  10        |
 _____________________________________________________________________________________________________________________|            |
 INTEGUMENTARY SYSTEM                      |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Mammary Gland                           | +                 +                                                      |  10        |
                                           |__________________________________________________________________________|____________|
   Skin                                    | +                 +                                                      |  10        |
 _____________________________________________________________________________________________________________________|            |
 MUSCULOSKELETAL SYSTEM                    |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Bone                                    | +                 +                                                      |  10        |
 _____________________________________________________________________________________________________________________|            |
 NERVOUS SYSTEM                            |                                                                          |            |
 _____________________________________________________________________________________________________________________|____________|
                                                                                                                                    
                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  
                                                                                                                                    
                                                                                                                                    
                                                             Page  16                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 1| 3| 3| 3| 3| 3| 1| 3| 3| 3| 3| 3| 3| 3| 3|                             |            |
                             DAY ON TEST   | 8| 6| 6| 6| 6| 6| 8| 6| 6| 6| 6| 6| 6| 6| 6|                             |            |
                                           | 6| 8| 8| 8| 8| 8| 6| 8| 8| 8| 8| 8| 8| 8| 8|                             |            |
 __________________________________________|__________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|                             |     O      |
   FISCHER 344 RATS MALE                   | 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|                             |     A      |
    70 PPM                                 | 6| 6| 6| 6| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 8|                             |     L      |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|                             |            |
 _____________________________________________________________________________________________________________________|____________|
 NERVOUS SYSTEM - cont                     |                                                                          |            |
                                           |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Brain                                   | +                 +                                                      |  11        |
                                           |__________________________________________________________________________|____________|
   Peripheral Nerve                        | +                 +                                                      |  10        |
                                           |__________________________________________________________________________|____________|
   Spinal Cord                             | +                 +                                                      |  10        |
 _____________________________________________________________________________________________________________________|            |
 RESPIRATORY SYSTEM                        |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Larynx                                  | +                 +                                                      |  10        |
                                           |__________________________________________________________________________|____________|
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
      Alveolar/Bronchiolar Adenoma         |                         X                                                |          1 |
                                           |__________________________________________________________________________|____________|
   Nose                                    | +                 +                                                      |  10        |
                                           |__________________________________________________________________________|____________|
   Trachea                                 | +                 +                                                      |  10        |
 _____________________________________________________________________________________________________________________|            |
 SPECIAL SENSES SYSTEM                     |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Eye                                     | +                 +                                                      |  10        |
 _____________________________________________________________________________________________________________________|            |
 URINARY SYSTEM                            |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Kidney                                  | +                 +                                                      |  10        |
                                           |__________________________________________________________________________|____________|
   Urinary Bladder                         | +                 +                       +                              |  11        |
 __________________________________________________________________________________________________________________________________ 
 SYSTEMIC LESIONS                          |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Multiple Organs                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
      Leukemia Mononuclear                 |                                                                          |          2 |
 __________________________________________________________________________________________________________________________________ 
                                                                                                                                    
                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  
                                                                                                                                    
                                                                                                                                    
                                                             Page  17                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 3| 3| 3| 1| 3| 3| 3| 1| 1| 3| 3| 1| 1| 3| 1| 3| 3| 1| 3| 1| 3| 3| 1| 3| 3|             
                             DAY ON TEST   | 6| 6| 6| 8| 6| 6| 6| 8| 8| 6| 6| 8| 8| 6| 6| 6| 6| 8| 6| 8| 6| 6| 8| 6| 6|             
                                           | 7| 7| 7| 6| 7| 7| 7| 6| 6| 7| 7| 6| 6| 7| 3| 7| 7| 6| 7| 6| 7| 7| 6| 7| 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|             
   FISCHER 344 RATS 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| 1| 1| 1| 1| 1| 1|             
    220 PPM                                | 8| 8| 8| 8| 8| 8| 8| 8| 8| 9| 9| 9| 9| 9| 9| 9| 9| 9| 9| 0| 0| 0| 0| 0| 0|             
                                           | 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                               |          +           +  +        +  +     +        +     +        +      |             
                                           |__________________________________________________________________________|             
   Intestine Large, Colon                  |          +           +  +        +  +     A        +     +        +      |             
                                           |__________________________________________________________________________|             
   Intestine Large, Rectum                 |          +           +  +        +  +     A        +     +        +      |             
                                           |__________________________________________________________________________|             
   Intestine Large, Cecum                  |          +           +  +        +  +     A        +     +        +      |             
                                           |__________________________________________________________________________|             
   Intestine Small, Duodenum               |          +           +  +        +  +     A        +     +        +      |             
                                           |__________________________________________________________________________|             
   Intestine Small, Jejunum                |          +           +  +        +  +     A        +     +        +      |             
                                           |__________________________________________________________________________|             
   Intestine Small, Ileum                  |          +           +  +        +  +     A        +     +        +      |             
                                           |__________________________________________________________________________|             
   Liver                                   |          +        +  +  +        +  +  +  +  +  +  +     +  +  +  +      |             
                                           |__________________________________________________________________________|             
   Mesentery                               |                                     +     +                              |             
                                           |__________________________________________________________________________|             
   Pancreas                                |          +           +  +        +  +     +        +     +        +      |             
                                           |__________________________________________________________________________|             
   Pharynx                                 |          +           +  +        +  +     +        +     +        +      |             
                                           |__________________________________________________________________________|             
   Salivary Glands                         |          +           +  +        +  +     +        +     +        +      |             
                                           |__________________________________________________________________________|             
   Stomach, Forestomach                    |          +           +  +        +  +     A        +     +        +      |             
                                           |__________________________________________________________________________|             
   Stomach, Glandular                      |          +           +  +        +  +     A        +     +        +      |             
 _____________________________________________________________________________________________________________________|             
 CARDIOVASCULAR SYSTEM                     |                                                                          |             
                                           |__________________________________________________________________________|             
   Blood Vessel                            |          +           +  +        +  +     +        +     +        +      |             
                                           |__________________________________________________________________________|             
   Heart                                   |          +           +  +        +  +     +        +     +        +      |             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM                          |                                                                          |             
                                           |__________________________________________________________________________|             
 __________________________________________|__________________________________________________________________________|             
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page  18                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 3| 3| 3| 1| 3| 3| 3| 1| 1| 3| 3| 1| 1| 3| 1| 3| 3| 1| 3| 1| 3| 3| 1| 3| 3|             
                             DAY ON TEST   | 6| 6| 6| 8| 6| 6| 6| 8| 8| 6| 6| 8| 8| 6| 6| 6| 6| 8| 6| 8| 6| 6| 8| 6| 6|             
                                           | 7| 7| 7| 6| 7| 7| 7| 6| 6| 7| 7| 6| 6| 7| 3| 7| 7| 6| 7| 6| 7| 7| 6| 7| 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|             
   FISCHER 344 RATS 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| 1| 1| 1| 1| 1| 1|             
    220 PPM                                | 8| 8| 8| 8| 8| 8| 8| 8| 8| 9| 9| 9| 9| 9| 9| 9| 9| 9| 9| 0| 0| 0| 0| 0| 0|             
                                           | 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                   |                                                                          |             
                                           |                                                                          |             
   Adrenal Cortex                          |          +           +  +        +  +     +        +     +        +      |             
                                           |__________________________________________________________________________|             
   Adrenal Medulla                         |       +  +           +  +        +  +     +        +     +        +      |             
      Ganglioneuroma                       |       X                                                                  |             
                                           |__________________________________________________________________________|             
   Islets, Pancreatic                      |          +           +  +        +  +     +        +     +        +      |             
                                           |__________________________________________________________________________|             
   Parathyroid Gland                       |          +           +  +        +  +     M        +     +        +      |             
                                           |__________________________________________________________________________|             
   Pituitary Gland                         |          +           +  +        +  +  +  +  +     +     +        +      |             
      Adenoma                              |                                        X     X                           |             
                                           |__________________________________________________________________________|             
   Thyroid Gland                           |          +           +  +        +  +     A        +     +        +      |             
 _____________________________________________________________________________________________________________________|             
 GENERAL BODY SYSTEM                       |                                                                          |             
    None                                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 GENITAL SYSTEM                            |                                                                          |             
                                           |__________________________________________________________________________|             
   Epididymis                              |          +           +  +        +  +     +        +     +        +      |             
      Mesothelioma Benign                  |                                                                          |             
                                           |__________________________________________________________________________|             
   Preputial Gland                         |          +           +  +        +  +     M        +     +        +      |             
                                           |__________________________________________________________________________|             
   Prostate                                |          +           +  +        +  +     +        +     +        +      |             
                                           |__________________________________________________________________________|             
   Seminal Vesicle                         |          +           +  +        +  +     +        +     +        +      |             
                                           |__________________________________________________________________________|             
   Testes                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Interstitial Cell, Adenoma           |    X                          X                                          |             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM                      |                                                                          |             
                                           |__________________________________________________________________________|             
   Bone Marrow                             |          +           +  +        +  +     M        +     +        +      |             
                                           |__________________________________________________________________________|             
   Lymph Node, Bronchial                   |          +           +  +        +  +     +        +     +        +      |             
 __________________________________________|__________________________________________________________________________|             
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page  19                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 3| 3| 3| 1| 3| 3| 3| 1| 1| 3| 3| 1| 1| 3| 1| 3| 3| 1| 3| 1| 3| 3| 1| 3| 3|             
                             DAY ON TEST   | 6| 6| 6| 8| 6| 6| 6| 8| 8| 6| 6| 8| 8| 6| 6| 6| 6| 8| 6| 8| 6| 6| 8| 6| 6|             
                                           | 7| 7| 7| 6| 7| 7| 7| 6| 6| 7| 7| 6| 6| 7| 3| 7| 7| 6| 7| 6| 7| 7| 6| 7| 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|             
   FISCHER 344 RATS 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| 1| 1| 1| 1| 1| 1|             
    220 PPM                                | 8| 8| 8| 8| 8| 8| 8| 8| 8| 9| 9| 9| 9| 9| 9| 9| 9| 9| 9| 0| 0| 0| 0| 0| 0|             
                                           | 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, Mandibular                  |          +           +  +     +  +  +     +        +     +        +      |             
                                           |__________________________________________________________________________|             
   Lymph Node, Mesenteric                  |          +           +  +        +  +     +        +     +        +      |             
                                           |__________________________________________________________________________|             
   Lymph Node, Mediastinal                 |          +           +  +        +  +     +        +     +        +      |             
                                           |__________________________________________________________________________|             
   Spleen                                  |          +           +  +        +  +     +  +     +     +        +      |             
                                           |__________________________________________________________________________|             
   Thymus                                  |          +           +  +        +  +     +        +     +        +      |             
 _____________________________________________________________________________________________________________________|             
 INTEGUMENTARY SYSTEM                      |                                                                          |             
                                           |__________________________________________________________________________|             
   Mammary Gland                           |          +           +  +        +  +     M        +     +        +      |             
                                           |__________________________________________________________________________|             
   Skin                                    |          +           +  +        +  +     M        +     +        +     +|             
      Sarcoma                              |                                                                         X|             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM                    |                                                                          |             
                                           |__________________________________________________________________________|             
   Bone                                    |          +  +        +  +        +  +     M        +     +        +      |             
                                           |__________________________________________________________________________|             
   Skeletal Muscle                         |                                           +                              |             
 _____________________________________________________________________________________________________________________|             
 NERVOUS SYSTEM                            |                                                                          |             
                                           |__________________________________________________________________________|             
   Brain                                   |          +           +  +        +  +     +        +     +        +      |             
                                           |__________________________________________________________________________|             
   Peripheral Nerve                        |          +           +  +        +  +     M        +     +        +      |             
                                           |__________________________________________________________________________|             
   Spinal Cord                             |          +           +  +        +  +     M        +     +        +      |             
 _____________________________________________________________________________________________________________________|             
 RESPIRATORY SYSTEM                        |                                                                          |             
                                           |__________________________________________________________________________|             
   Larynx                                  |          +           +  +        +  +     A        +     +        +      |             
                                           |__________________________________________________________________________|             
 __________________________________________|__________________________________________________________________________|             
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page  20                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 3| 3| 3| 1| 3| 3| 3| 1| 1| 3| 3| 1| 1| 3| 1| 3| 3| 1| 3| 1| 3| 3| 1| 3| 3|             
                             DAY ON TEST   | 6| 6| 6| 8| 6| 6| 6| 8| 8| 6| 6| 8| 8| 6| 6| 6| 6| 8| 6| 8| 6| 6| 8| 6| 6|             
                                           | 7| 7| 7| 6| 7| 7| 7| 6| 6| 7| 7| 6| 6| 7| 3| 7| 7| 6| 7| 6| 7| 7| 6| 7| 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|             
   FISCHER 344 RATS 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| 1| 1| 1| 1| 1| 1|             
    220 PPM                                | 8| 8| 8| 8| 8| 8| 8| 8| 8| 9| 9| 9| 9| 9| 9| 9| 9| 9| 9| 0| 0| 0| 0| 0| 0|             
                                           | 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                 |                                                                          |             
                                           |                                                                          |             
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Nose                                    |          +           +  +        +  +     +        +     +        +      |             
                                           |__________________________________________________________________________|             
   Trachea                                 |          +           +  +        +  +     A        +     +        +      |             
 _____________________________________________________________________________________________________________________|             
 SPECIAL SENSES SYSTEM                     |                                                                          |             
                                           |__________________________________________________________________________|             
   Eye                                     |          +           +  +        +  +     +        +     +        +      |             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM                            |                                                                          |             
                                           |__________________________________________________________________________|             
   Kidney                                  |       +  +           +  +        +  +     +        +     +        +      |             
                                           |__________________________________________________________________________|             
   Urinary Bladder                         |          +  +        +  +        +  +  +  A        +     +        +      |             
 __________________________________________|__________________________________________________________________________|             
 SYSTEMIC LESIONS                          |                                                                          |             
                                            __________________________________________________________________________|             
   Multiple Organs                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Mesothelioma Benign                  |                                                                          |             
 __________________________________________|__________________________________________________________________________|             
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page  21                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 3| 3| 3| 1| 3| 3| 3| 3| 3| 3| 3| 1| 3| 3| 3|                             |            |
                             DAY ON TEST   | 6| 6| 6| 8| 6| 6| 6| 6| 6| 6| 6| 8| 6| 6| 6|                             |            |
                                           | 7| 7| 7| 6| 7| 7| 7| 7| 7| 7| 7| 6| 7| 7| 7|                             |            |
 __________________________________________|__________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|                             |     O      |
   FISCHER 344 RATS MALE                   | 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|                             |     A      |
    220 PPM                                | 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2|                             |     L      |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|                             |            |
 _____________________________________________________________________________________________________________________|____________|
 ALIMENTARY SYSTEM                         |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Esophagus                               |          +                       +                                       |  11        |
                                           |__________________________________________________________________________|____________|
   Intestine Large, Colon                  |          +                       +                                       |  10        |
                                           |__________________________________________________________________________|____________|
   Intestine Large, Rectum                 |          +                       +                                       |  10        |
                                           |__________________________________________________________________________|____________|
   Intestine Large, Cecum                  |          +                       +                                       |  10        |
                                           |__________________________________________________________________________|____________|
   Intestine Small, Duodenum               |          +                       +                                       |  10        |
                                           |__________________________________________________________________________|____________|
   Intestine Small, Jejunum                |          +                       +                                       |  10        |
                                           |__________________________________________________________________________|____________|
   Intestine Small, Ileum                  |          +                       +                                       |  10        |
                                           |__________________________________________________________________________|____________|
   Liver                                   |          +           +  +  +     +  +  +                                 |  22        |
                                           |__________________________________________________________________________|____________|
   Mesentery                               |                                                                          |   2        |
                                           |__________________________________________________________________________|____________|
   Pancreas                                |          +                       +                                       |  11        |
                                           |__________________________________________________________________________|____________|
   Pharynx                                 |          +                       +                                       |  11        |
                                           |__________________________________________________________________________|____________|
   Salivary Glands                         |          +                       +                                       |  11        |
                                           |__________________________________________________________________________|____________|
   Stomach, Forestomach                    |          +                       +                                       |  10        |
                                           |__________________________________________________________________________|____________|
   Stomach, Glandular                      |          +                       +                                       |  10        |
 _____________________________________________________________________________________________________________________|            |
 CARDIOVASCULAR SYSTEM                     |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Blood Vessel                            |          +                       +                                       |  11        |
                                           |__________________________________________________________________________|____________|
 _____________________________________________________________________________________________________________________|____________|
                                                                                                                                    
                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  
                                                                                                                                    
                                                                                                                                    
                                                             Page  22                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 3| 3| 3| 1| 3| 3| 3| 3| 3| 3| 3| 1| 3| 3| 3|                             |            |
                             DAY ON TEST   | 6| 6| 6| 8| 6| 6| 6| 6| 6| 6| 6| 8| 6| 6| 6|                             |            |
                                           | 7| 7| 7| 6| 7| 7| 7| 7| 7| 7| 7| 6| 7| 7| 7|                             |            |
 __________________________________________|__________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|                             |     O      |
   FISCHER 344 RATS MALE                   | 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|                             |     A      |
    220 PPM                                | 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2|                             |     L      |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|                             |            |
 _____________________________________________________________________________________________________________________|____________|
 CARDIOVASCULAR SYSTEM - cont              |                                                                          |            |
                                           |                                                                          |            |
   Heart                                   |          +                       +                                       |  11        |
 _____________________________________________________________________________________________________________________|            |
 ENDOCRINE SYSTEM                          |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Adrenal Cortex                          |          +                       +                                       |  11        |
                                           |__________________________________________________________________________|____________|
   Adrenal Medulla                         |          +                       +                                       |  12        |
      Ganglioneuroma                       |                                                                          |          1 |
                                           |__________________________________________________________________________|____________|
   Islets, Pancreatic                      |          +                       +                                       |  11        |
                                           |__________________________________________________________________________|____________|
   Parathyroid Gland                       |          +                       +                                       |  10        |
                                           |__________________________________________________________________________|____________|
   Pituitary Gland                         |          +                       +        +                              |  14        |
      Adenoma                              |                                           X                              |          3 |
                                           |__________________________________________________________________________|____________|
   Thyroid Gland                           |          +                       +                                       |  10        |
 _____________________________________________________________________________________________________________________|            |
 GENERAL BODY SYSTEM                       |                                                                          |            |
    None                                   |                                                                          |            |
 _____________________________________________________________________________________________________________________|            |
 GENITAL SYSTEM                            |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Epididymis                              |          +                       +     +                                 |  12        |
      Mesothelioma Benign                  |                                        X                                 |          1 |
                                           |__________________________________________________________________________|____________|
   Preputial Gland                         |          +                       +                                       |  10        |
                                           |__________________________________________________________________________|____________|
   Prostate                                |          +                       +                                       |  11        |
                                           |__________________________________________________________________________|____________|
   Seminal Vesicle                         |          +                       +                                       |  11        |
                                           |__________________________________________________________________________|____________|
 _____________________________________________________________________________________________________________________|____________|
                                                                                                                                    
                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  
                                                                                                                                    
                                                                                                                                    
                                                             Page  23                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 3| 3| 3| 1| 3| 3| 3| 3| 3| 3| 3| 1| 3| 3| 3|                             |            |
                             DAY ON TEST   | 6| 6| 6| 8| 6| 6| 6| 6| 6| 6| 6| 8| 6| 6| 6|                             |            |
                                           | 7| 7| 7| 6| 7| 7| 7| 7| 7| 7| 7| 6| 7| 7| 7|                             |            |
 __________________________________________|__________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|                             |     O      |
   FISCHER 344 RATS MALE                   | 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|                             |     A      |
    220 PPM                                | 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2|                             |     L      |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|                             |            |
 _____________________________________________________________________________________________________________________|____________|
 GENITAL SYSTEM - cont                     |                                                                          |            |
                                           |                                                                          |            |
   Testes                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
      Interstitial Cell, Adenoma           |                   X  X                                                   |          4 |
 _____________________________________________________________________________________________________________________|            |
 HEMATOPOIETIC SYSTEM                      |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Bone Marrow                             |          +                       +                                       |  10        |
                                           |__________________________________________________________________________|____________|
   Lymph Node, Bronchial                   |          +                       +                                       |  11        |
                                           |__________________________________________________________________________|____________|
   Lymph Node, Mandibular                  |          +                       +                                       |  12        |
                                           |__________________________________________________________________________|____________|
   Lymph Node, Mesenteric                  |          +                       +                                       |  11        |
                                           |__________________________________________________________________________|____________|
   Lymph Node, Mediastinal                 |          +              +        +                                       |  12        |
                                           |__________________________________________________________________________|____________|
   Spleen                                  |          +                       +                                       |  12        |
                                           |__________________________________________________________________________|____________|
   Thymus                                  |          +                       +                                       |  11        |
 _____________________________________________________________________________________________________________________|            |
 INTEGUMENTARY SYSTEM                      |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Mammary Gland                           |          +                       +                                       |  10        |
                                           |__________________________________________________________________________|____________|
   Skin                                    |          +                       +                                       |  11        |
      Sarcoma                              |                                                                          |          1 |
 _____________________________________________________________________________________________________________________|            |
 MUSCULOSKELETAL SYSTEM                    |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Bone                                    |          +                       +                                       |  11        |
                                           |__________________________________________________________________________|____________|
   Skeletal Muscle                         |                                                                          |   1        |
 _____________________________________________________________________________________________________________________|            |
                                                                                                                                    
                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  
                                                                                                                                    
                                                                                                                                    
                                                             Page  24                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 3| 3| 3| 1| 3| 3| 3| 3| 3| 3| 3| 1| 3| 3| 3|                             |            |
                             DAY ON TEST   | 6| 6| 6| 8| 6| 6| 6| 6| 6| 6| 6| 8| 6| 6| 6|                             |            |
                                           | 7| 7| 7| 6| 7| 7| 7| 7| 7| 7| 7| 6| 7| 7| 7|                             |            |
 __________________________________________|__________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|                             |     O      |
   FISCHER 344 RATS MALE                   | 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|                             |     A      |
    220 PPM                                | 0| 0| 0| 0| 1| 1| 1| 1| 1| 1| 1| 1| 1| 1| 2|                             |     L      |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|                             |            |
 _____________________________________________________________________________________________________________________|____________|
 NERVOUS SYSTEM                            |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Brain                                   |          +                       +                                       |  11        |
                                           |__________________________________________________________________________|____________|
   Peripheral Nerve                        |          +                       +                                       |  10        |
                                           |__________________________________________________________________________|____________|
   Spinal Cord                             |          +                       +                                       |  10        |
 _____________________________________________________________________________________________________________________|            |
 RESPIRATORY SYSTEM                        |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Larynx                                  |          +                       +                                       |  10        |
                                           |__________________________________________________________________________|____________|
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Nose                                    |          +                       +                                       |  11        |
                                           |__________________________________________________________________________|____________|
   Trachea                                 |          +                       +                                       |  10        |
 _____________________________________________________________________________________________________________________|            |
 SPECIAL SENSES SYSTEM                     |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Eye                                     |          +                       +                                       |  11        |
 _____________________________________________________________________________________________________________________|            |
 URINARY SYSTEM                            |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Kidney                                  |          +                       +                                       |  12        |
                                           |__________________________________________________________________________|____________|
   Urinary Bladder                         |          +     +                 +                                       |  13        |
 __________________________________________________________________________________________________________________________________ 
 SYSTEMIC LESIONS                          |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Multiple Organs                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
      Mesothelioma Benign                  |                                        X                                 |          1 |
 __________________________________________________________________________________________________________________________________ 
                                                                                                                                    
                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page  25                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 3| 1| 3| 3| 1| 3| 3| 3| 3| 1| 3| 3| 3| 3| 1| 3| 3| 3| 3| 3| 3| 3| 1| 3| 3|             
                             DAY ON TEST   | 6| 8| 6| 6| 8| 6| 6| 6| 6| 8| 6| 6| 6| 6| 8| 6| 6| 6| 6| 6| 6| 6| 8| 6| 6|             
                                           | 7| 6| 7| 7| 6| 7| 7| 7| 7| 6| 7| 7| 7| 7| 6| 7| 7| 7| 7| 7| 7| 7| 6| 7| 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|             
   FISCHER 344 RATS 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   | 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|             
    700 PPM                                | 2| 2| 2| 2| 2| 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4|             
                                           | 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                               |    +        +              +              +                       +      |             
                                           |__________________________________________________________________________|             
   Intestine Large, Colon                  |    +        +              +              +                       +      |             
                                           |__________________________________________________________________________|             
   Intestine Large, Rectum                 |    +        +              +              +                       +      |             
                                           |__________________________________________________________________________|             
   Intestine Large, Cecum                  |    +        +              +              +                       +      |             
                                           |__________________________________________________________________________|             
   Intestine Small, Duodenum               |    +        +              +              +                       +      |             
                                           |__________________________________________________________________________|             
   Intestine Small, Jejunum                |    +        +              +              +                       +      |             
                                           |__________________________________________________________________________|             
   Intestine Small, Ileum                  |    +        +              +              +                       +      |             
                                           |__________________________________________________________________________|             
   Liver                                   |    +     +  +  +        +  +              +                       +     +|             
                                           |__________________________________________________________________________|             
   Mesentery                               |                                                                          |             
                                           |__________________________________________________________________________|             
   Pancreas                                |    +        +              +              +                       +      |             
                                           |__________________________________________________________________________|             
   Pharynx                                 |    +        +              +              +                       +      |             
                                           |__________________________________________________________________________|             
   Salivary Glands                         |    +        +              +              +                       +      |             
                                           |__________________________________________________________________________|             
   Stomach, Forestomach                    |    +        +              +              +                       +      |             
                                           |__________________________________________________________________________|             
   Stomach, Glandular                      |    +        +              +              +                       +      |             
 _____________________________________________________________________________________________________________________|             
 CARDIOVASCULAR SYSTEM                     |                                                                          |             
                                           |__________________________________________________________________________|             
   Blood Vessel                            |    +        +              +              +                       +      |             
                                           |__________________________________________________________________________|             
   Heart                                   |    +        +              +              +                       +      |             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM                          |                                                                          |             
                                           |__________________________________________________________________________|             
 __________________________________________|__________________________________________________________________________|             
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page  26                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 3| 1| 3| 3| 1| 3| 3| 3| 3| 1| 3| 3| 3| 3| 1| 3| 3| 3| 3| 3| 3| 3| 1| 3| 3|             
                             DAY ON TEST   | 6| 8| 6| 6| 8| 6| 6| 6| 6| 8| 6| 6| 6| 6| 8| 6| 6| 6| 6| 6| 6| 6| 8| 6| 6|             
                                           | 7| 6| 7| 7| 6| 7| 7| 7| 7| 6| 7| 7| 7| 7| 6| 7| 7| 7| 7| 7| 7| 7| 6| 7| 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|             
   FISCHER 344 RATS 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   | 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|             
    700 PPM                                | 2| 2| 2| 2| 2| 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4|             
                                           | 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                   |                                                                          |             
                                           |                                                                          |             
   Adrenal Cortex                          |    +        +              +              +                       +      |             
                                           |__________________________________________________________________________|             
   Adrenal Medulla                         |    +        +              +              +                       +      |             
                                           |__________________________________________________________________________|             
   Islets, Pancreatic                      |    +        +              +              +                       +      |             
                                           |__________________________________________________________________________|             
   Parathyroid Gland                       |    +        +              +              +                       +      |             
                                           |__________________________________________________________________________|             
   Pituitary Gland                         |    +        +              +              +     +     +           +      |             
      Adenoma                              |                                                 X     X                  |             
                                           |__________________________________________________________________________|             
   Thyroid Gland                           |    +        +              +              +                       +      |             
 _____________________________________________________________________________________________________________________|             
 GENERAL BODY SYSTEM                       |                                                                          |             
    None                                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 GENITAL SYSTEM                            |                                                                          |             
                                           |__________________________________________________________________________|             
   Epididymis                              |    +        +              +              +                       +      |             
                                           |__________________________________________________________________________|             
   Preputial Gland                         |    +        +              +              +                       +      |             
                                           |__________________________________________________________________________|             
   Prostate                                |    +        +              +              +                       +      |             
                                           |__________________________________________________________________________|             
   Seminal Vesicle                         |    +        +              +              +                       +      |             
                                           |__________________________________________________________________________|             
   Testes                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Interstitial Cell, Adenoma           |                                     X  X     X           X               |             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM                      |                                                                          |             
                                           |__________________________________________________________________________|             
   Bone Marrow                             |    +        +              +              +                       +      |             
                                           |__________________________________________________________________________|             
   Lymph Node, Bronchial                   |    +        +              +              +                       +      |             
                                           |__________________________________________________________________________|             
   Lymph Node, Mandibular                  |    +        +              +              +                       +      |             
 __________________________________________|__________________________________________________________________________|             
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page  27                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 3| 1| 3| 3| 1| 3| 3| 3| 3| 1| 3| 3| 3| 3| 1| 3| 3| 3| 3| 3| 3| 3| 1| 3| 3|             
                             DAY ON TEST   | 6| 8| 6| 6| 8| 6| 6| 6| 6| 8| 6| 6| 6| 6| 8| 6| 6| 6| 6| 6| 6| 6| 8| 6| 6|             
                                           | 7| 6| 7| 7| 6| 7| 7| 7| 7| 6| 7| 7| 7| 7| 6| 7| 7| 7| 7| 7| 7| 7| 6| 7| 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|             
   FISCHER 344 RATS 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   | 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|             
    700 PPM                                | 2| 2| 2| 2| 2| 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4|             
                                           | 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, Mesenteric                  |    +        +              +              +                       +      |             
                                           |__________________________________________________________________________|             
   Lymph Node, Mediastinal                 |    +        +              +           +  +                       +      |             
                                           |__________________________________________________________________________|             
   Spleen                                  |    +        +              +              +        +              +      |             
                                           |__________________________________________________________________________|             
   Thymus                                  |    +        +              +              +                       +      |             
 _____________________________________________________________________________________________________________________|             
 INTEGUMENTARY SYSTEM                      |                                                                          |             
                                           |__________________________________________________________________________|             
   Mammary Gland                           |    +        +              +        +     +                       +      |             
      Fibroadenoma                         |                                     X                                    |             
                                           |__________________________________________________________________________|             
   Skin                                    |    +        +              +        +     +                       +      |             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM                    |                                                                          |             
                                           |__________________________________________________________________________|             
   Bone                                    |    +        +              +              +                       +      |             
 _____________________________________________________________________________________________________________________|             
 NERVOUS SYSTEM                            |                                                                          |             
                                           |__________________________________________________________________________|             
   Brain                                   |    +        +              +              +                       +      |             
                                           |__________________________________________________________________________|             
   Peripheral Nerve                        |    +        +              +              +                       +      |             
                                           |__________________________________________________________________________|             
   Spinal Cord                             |    +        +              +              +                       +      |             
 _____________________________________________________________________________________________________________________|             
 RESPIRATORY SYSTEM                        |                                                                          |             
                                           |__________________________________________________________________________|             
   Larynx                                  |    +        +              +              +                       +      |             
                                           |__________________________________________________________________________|             
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Nose                                    |    +        +              +              +                       +      |             
                                           |__________________________________________________________________________|             
 __________________________________________|__________________________________________________________________________|             
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page  28                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 3| 1| 3| 3| 1| 3| 3| 3| 3| 1| 3| 3| 3| 3| 1| 3| 3| 3| 3| 3| 3| 3| 1| 3| 3|             
                             DAY ON TEST   | 6| 8| 6| 6| 8| 6| 6| 6| 6| 8| 6| 6| 6| 6| 8| 6| 6| 6| 6| 6| 6| 6| 8| 6| 6|             
                                           | 7| 6| 7| 7| 6| 7| 7| 7| 7| 6| 7| 7| 7| 7| 6| 7| 7| 7| 7| 7| 7| 7| 6| 7| 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|             
   FISCHER 344 RATS 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   | 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|             
    700 PPM                                | 2| 2| 2| 2| 2| 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4| 4| 4| 4| 4| 4|             
                                           | 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                 |                                                                          |             
                                           |                                                                          |             
   Trachea                                 | +  +        +              +              +                       +      |             
 _____________________________________________________________________________________________________________________|             
 SPECIAL SENSES SYSTEM                     |                                                                          |             
                                           |__________________________________________________________________________|             
   Eye                                     |    +        +              +              +                       +      |             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM                            |                                                                          |             
                                           |__________________________________________________________________________|             
   Kidney                                  |    +        +     +        +              +                       +      |             
                                           |__________________________________________________________________________|             
   Urinary Bladder                         |    +        +              +              +                       +      |             
 __________________________________________|__________________________________________________________________________|             
 SYSTEMIC LESIONS                          |                                                                          |             
                                            __________________________________________________________________________|             
   Multiple Organs                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 __________________________________________|__________________________________________________________________________|             
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page  29                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 3| 3| 1| 1| 3| 3| 3| 3| 3| 3| 1| 3| 1| 3| 1|                             |            |
                             DAY ON TEST   | 6| 6| 8| 8| 6| 6| 6| 6| 6| 6| 8| 6| 8| 6| 8|                             |            |
                                           | 7| 7| 6| 6| 7| 7| 7| 7| 7| 7| 6| 7| 6| 7| 6|                             |            |
 __________________________________________|__________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|                             |     O      |
   FISCHER 344 RATS MALE                   | 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|                             |     A      |
    700 PPM                                | 4| 4| 4| 4| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 6|                             |     L      |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|                             |            |
 _____________________________________________________________________________________________________________________|____________|
 ALIMENTARY SYSTEM                         |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Esophagus                               |       +  +                    +     +     +                              |  10        |
                                           |__________________________________________________________________________|____________|
   Intestine Large, Colon                  |       +  +                    +     +     +                              |  10        |
                                           |__________________________________________________________________________|____________|
   Intestine Large, Rectum                 |       +  +                    +     +     +                              |  10        |
                                           |__________________________________________________________________________|____________|
   Intestine Large, Cecum                  |       +  +                    +     +     +                              |  10        |
                                           |__________________________________________________________________________|____________|
   Intestine Small, Duodenum               |       +  +                    +     +     +                              |  10        |
                                           |__________________________________________________________________________|____________|
   Intestine Small, Jejunum                |       +  +                    +     +     +                              |  10        |
                                           |__________________________________________________________________________|____________|
   Intestine Small, Ileum                  |       +  +                    +     +     +                              |  10        |
                                           |__________________________________________________________________________|____________|
   Liver                                   |       +  +                 +  +     +     +                              |  15        |
                                           |__________________________________________________________________________|____________|
   Mesentery                               | +                             +                                          |   2        |
                                           |__________________________________________________________________________|____________|
   Pancreas                                |       +  +                    +     +     +                              |  10        |
                                           |__________________________________________________________________________|____________|
   Pharynx                                 |       +  +                    +     +     +                              |  10        |
                                           |__________________________________________________________________________|____________|
   Salivary Glands                         |       +  +                    +     +     +                              |  10        |
                                           |__________________________________________________________________________|____________|
   Stomach, Forestomach                    |       +  +                    +     +     +                              |  10        |
                                           |__________________________________________________________________________|____________|
   Stomach, Glandular                      |       +  +                    +     +     +                              |  10        |
 _____________________________________________________________________________________________________________________|            |
 CARDIOVASCULAR SYSTEM                     |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Blood Vessel                            |       +  +                    +     +     +                              |  10        |
                                           |__________________________________________________________________________|____________|
 _____________________________________________________________________________________________________________________|____________|
                                                                                                                                    
                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  
                                                                                                                                    
                                                                                                                                    
                                                             Page  30                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 3| 3| 1| 1| 3| 3| 3| 3| 3| 3| 1| 3| 1| 3| 1|                             |            |
                             DAY ON TEST   | 6| 6| 8| 8| 6| 6| 6| 6| 6| 6| 8| 6| 8| 6| 8|                             |            |
                                           | 7| 7| 6| 6| 7| 7| 7| 7| 7| 7| 6| 7| 6| 7| 6|                             |            |
 __________________________________________|__________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|                             |     O      |
   FISCHER 344 RATS MALE                   | 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|                             |     A      |
    700 PPM                                | 4| 4| 4| 4| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 6|                             |     L      |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|                             |            |
 _____________________________________________________________________________________________________________________|____________|
 CARDIOVASCULAR SYSTEM - cont              |                                                                          |            |
                                           |                                                                          |            |
   Heart                                   |       +  +                    +     +     +                              |  10        |
 _____________________________________________________________________________________________________________________|            |
 ENDOCRINE SYSTEM                          |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Adrenal Cortex                          |       +  +                    +     +     +                              |  10        |
                                           |__________________________________________________________________________|____________|
   Adrenal Medulla                         |       +  +                    +     +     +                              |  10        |
                                           |__________________________________________________________________________|____________|
   Islets, Pancreatic                      |       +  +                    +     +     +                              |  10        |
                                           |__________________________________________________________________________|____________|
   Parathyroid Gland                       |       +  +                    +     +     +                              |  10        |
                                           |__________________________________________________________________________|____________|
   Pituitary Gland                         |       +  +                 +  +  +  +     +                              |  14        |
      Adenoma                              |                            X     X                                       |          4 |
                                           |__________________________________________________________________________|____________|
   Thyroid Gland                           |       +  +                    +     +     +                              |  10        |
 _____________________________________________________________________________________________________________________|            |
 GENERAL BODY SYSTEM                       |                                                                          |            |
    None                                   |                                                                          |            |
 _____________________________________________________________________________________________________________________|            |
 GENITAL SYSTEM                            |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Epididymis                              |       +  +                    +     +     +                              |  10        |
                                           |__________________________________________________________________________|____________|
   Preputial Gland                         | +     +  +           +        +     +     +                              |  12        |
                                           |__________________________________________________________________________|____________|
   Prostate                                |       +  +                    +     +     +                              |  10        |
                                           |__________________________________________________________________________|____________|
   Seminal Vesicle                         |       +  +                    +     +     +                              |  10        |
                                           |__________________________________________________________________________|____________|
   Testes                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
      Interstitial Cell, Adenoma           | X           X  X                                                         |          7 |
 _____________________________________________________________________________________________________________________|____________|
                                                                                                                                    
                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  
                                                                                                                                    
                                                                                                                                    
                                                             Page  31                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 3| 3| 1| 1| 3| 3| 3| 3| 3| 3| 1| 3| 1| 3| 1|                             |            |
                             DAY ON TEST   | 6| 6| 8| 8| 6| 6| 6| 6| 6| 6| 8| 6| 8| 6| 8|                             |            |
                                           | 7| 7| 6| 6| 7| 7| 7| 7| 7| 7| 6| 7| 6| 7| 6|                             |            |
 __________________________________________|__________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|                             |     O      |
   FISCHER 344 RATS MALE                   | 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|                             |     A      |
    700 PPM                                | 4| 4| 4| 4| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 6|                             |     L      |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|                             |            |
 _____________________________________________________________________________________________________________________|____________|
 HEMATOPOIETIC SYSTEM                      |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Bone Marrow                             |       +  +                    +     +     +                              |  10        |
                                           |__________________________________________________________________________|____________|
   Lymph Node, Bronchial                   |       +  +                    +     +     +                              |  10        |
                                           |__________________________________________________________________________|____________|
   Lymph Node, Mandibular                  |       +  +                 +  +     +     +                              |  11        |
                                           |__________________________________________________________________________|____________|
   Lymph Node, Mesenteric                  |       +  +                    +     +     +                              |  10        |
                                           |__________________________________________________________________________|____________|
   Lymph Node, Mediastinal                 |       +  +                    +     +     +                              |  11        |
                                           |__________________________________________________________________________|____________|
   Spleen                                  |    +  +  +                 +  +     +     +                              |  13        |
                                           |__________________________________________________________________________|____________|
   Thymus                                  |       +  +                    +     +     +                              |  10        |
 _____________________________________________________________________________________________________________________|            |
 INTEGUMENTARY SYSTEM                      |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Mammary Gland                           |       +  +                    +     +     +                              |  11        |
      Fibroadenoma                         |                                                                          |          1 |
                                           |__________________________________________________________________________|____________|
   Skin                                    | +     +  +                    +     +     +                              |  12        |
 _____________________________________________________________________________________________________________________|            |
 MUSCULOSKELETAL SYSTEM                    |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Bone                                    |       +  +                    +     +     +                              |  10        |
 _____________________________________________________________________________________________________________________|            |
 NERVOUS SYSTEM                            |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Brain                                   |       +  +                    +     +     +                              |  10        |
                                           |__________________________________________________________________________|____________|
   Peripheral Nerve                        |       +  +                    +     +     +                              |  10        |
                                           |__________________________________________________________________________|____________|
   Spinal Cord                             |       +  +                    +     +     +                              |  10        |
 _____________________________________________________________________________________________________________________|____________|
                                                                                                                                    
                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  
                                                                                                                                    
                                                                                                                                    
                                                             Page  32                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 3| 3| 1| 1| 3| 3| 3| 3| 3| 3| 1| 3| 1| 3| 1|                             |            |
                             DAY ON TEST   | 6| 6| 8| 8| 6| 6| 6| 6| 6| 6| 8| 6| 8| 6| 8|                             |            |
                                           | 7| 7| 6| 6| 7| 7| 7| 7| 7| 7| 6| 7| 6| 7| 6|                             |            |
 __________________________________________|__________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|                             |     O      |
   FISCHER 344 RATS MALE                   | 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|                             |     A      |
    700 PPM                                | 4| 4| 4| 4| 5| 5| 5| 5| 5| 5| 5| 5| 5| 5| 6|                             |     L      |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|                             |            |
 _____________________________________________________________________________________________________________________|____________|
 RESPIRATORY SYSTEM                        |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Larynx                                  |       +  +                    +     +     +                              |  10        |
                                           |__________________________________________________________________________|____________|
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Nose                                    |       +  +                    +     +     +                              |  10        |
                                           |__________________________________________________________________________|____________|
   Trachea                                 |       +  +                    +     +     +                              |  11        |
 _____________________________________________________________________________________________________________________|            |
 SPECIAL SENSES SYSTEM                     |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Eye                                     |    +  +  +                    +     +     +                              |  11        |
 _____________________________________________________________________________________________________________________|            |
 URINARY SYSTEM                            |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Kidney                                  |       +  +              +     +     +     +                              |  12        |
                                           |__________________________________________________________________________|____________|
   Urinary Bladder                         |       +  +                    +     +     +                              |  10        |
 __________________________________________________________________________________________________________________________________ 
 SYSTEMIC LESIONS                          |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Multiple Organs                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
 __________________________________________________________________________________________________________________________________ 
                                                                                                                                    
                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page  33                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 3| 3| 3| 3| 3| 3| 1| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 1| 3| 3| 1| 1| 3| 3| 1|             
                             DAY ON TEST   | 6| 6| 6| 6| 6| 6| 8| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 8| 6| 6| 8| 8| 6| 6| 8|             
                                           | 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|             
 __________________________________________|__________________________________________________________________________|             
                                           | 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|             
   FISCHER 344 RATS 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   | 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|             
    2200 PPM                               | 6| 6| 6| 6| 6| 6| 6| 6| 6| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 8| 8| 8| 8| 8| 8|             
                                           | 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                               |                   +                                +        +  +        +|             
                                           |__________________________________________________________________________|             
   Intestine Large, Colon                  |                   +                                +        +  +        +|             
                                           |__________________________________________________________________________|             
   Intestine Large, Rectum                 |                   +                                +        +  +        +|             
                                           |__________________________________________________________________________|             
   Intestine Large, Cecum                  |                   +                                +        +  +        +|             
                                           |__________________________________________________________________________|             
   Intestine Small, Duodenum               |                   +                                +        +  +        +|             
                                           |__________________________________________________________________________|             
   Intestine Small, Jejunum                |                   +                                +        +  +        +|             
                                           |__________________________________________________________________________|             
   Intestine Small, Ileum                  |                   +                                +        +  +        +|             
                                           |__________________________________________________________________________|             
   Liver                                   |       +     +     +     +  +     +        +        +        +  +        +|             
                                           |__________________________________________________________________________|             
   Mesentery                               |                                     +                    +               |             
                                           |__________________________________________________________________________|             
   Pancreas                                |                   +                                +        +  +        +|             
                                           |__________________________________________________________________________|             
   Pharynx                                 |                   +                                +        +  +        +|             
                                           |__________________________________________________________________________|             
   Salivary Glands                         |                   +                                +        +  +        +|             
                                           |__________________________________________________________________________|             
   Stomach, Forestomach                    |                   +                                +        +  +        +|             
                                           |__________________________________________________________________________|             
   Stomach, Glandular                      |                   +                                +        +  +        +|             
 _____________________________________________________________________________________________________________________|             
 CARDIOVASCULAR SYSTEM                     |                                                                          |             
                                           |__________________________________________________________________________|             
   Blood Vessel                            |                   +                                +        +  +        +|             
                                           |__________________________________________________________________________|             
   Heart                                   |                   +                                +        +  +        +|             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM                          |                                                                          |             
                                           |__________________________________________________________________________|             
 __________________________________________|__________________________________________________________________________|             
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page  34                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 3| 3| 3| 3| 3| 3| 1| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 1| 3| 3| 1| 1| 3| 3| 1|             
                             DAY ON TEST   | 6| 6| 6| 6| 6| 6| 8| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 8| 6| 6| 8| 8| 6| 6| 8|             
                                           | 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|             
 __________________________________________|__________________________________________________________________________|             
                                           | 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|             
   FISCHER 344 RATS 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   | 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|             
    2200 PPM                               | 6| 6| 6| 6| 6| 6| 6| 6| 6| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 8| 8| 8| 8| 8| 8|             
                                           | 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                   |                                                                          |             
                                           |                                                                          |             
   Adrenal Cortex                          |                   +                                +        +  +        +|             
                                           |__________________________________________________________________________|             
   Adrenal Medulla                         |                   +                                +        +  +        +|             
                                           |__________________________________________________________________________|             
   Islets, Pancreatic                      |                   +                                +        +  +        +|             
                                           |__________________________________________________________________________|             
   Parathyroid Gland                       |                   +                                +        +  +        +|             
                                           |__________________________________________________________________________|             
   Pituitary Gland                         |             +  +  +                       +        +        +  +        +|             
      Adenoma                              |                X                          X                              |             
                                           |__________________________________________________________________________|             
   Thyroid Gland                           |                   +                                +        +  +        +|             
 _____________________________________________________________________________________________________________________|             
 GENERAL BODY SYSTEM                       |                                                                          |             
    None                                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 GENITAL SYSTEM                            |                                                                          |             
                                           |__________________________________________________________________________|             
   Epididymis                              |                   +                                +        +  +  +     +|             
      Mesothelioma NOS                     |                                                                   X      |             
                                           |__________________________________________________________________________|             
   Preputial Gland                         |                   +                                +        +  +        +|             
                                           |__________________________________________________________________________|             
   Prostate                                |                   +                                +        +  +        +|             
                                           |__________________________________________________________________________|             
   Seminal Vesicle                         |                   +                                +        +  +        +|             
                                           |__________________________________________________________________________|             
   Testes                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Interstitial Cell, Adenoma           |       X                 X  X                                      X      |             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM                      |                                                                          |             
                                           |__________________________________________________________________________|             
   Bone Marrow                             |                   +                                +        +  +        +|             
                                           |__________________________________________________________________________|             
   Lymph Node, Bronchial                   |                   +                       +        +        +  +        +|             
                                           |__________________________________________________________________________|             
 __________________________________________|__________________________________________________________________________|             
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page  35                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 3| 3| 3| 3| 3| 3| 1| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 1| 3| 3| 1| 1| 3| 3| 1|             
                             DAY ON TEST   | 6| 6| 6| 6| 6| 6| 8| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 8| 6| 6| 8| 8| 6| 6| 8|             
                                           | 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|             
 __________________________________________|__________________________________________________________________________|             
                                           | 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|             
   FISCHER 344 RATS 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   | 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|             
    2200 PPM                               | 6| 6| 6| 6| 6| 6| 6| 6| 6| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 8| 8| 8| 8| 8| 8|             
                                           | 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, Mandibular                  |                   +                                +        +  +        +|             
                                           |__________________________________________________________________________|             
   Lymph Node, Mesenteric                  |                   +                                +        +  +        +|             
                                           |__________________________________________________________________________|             
   Lymph Node, Mediastinal                 |                   +                                +        +  +        +|             
                                           |__________________________________________________________________________|             
   Spleen                                  |                   +                       +     +  +        +  +        +|             
                                           |__________________________________________________________________________|             
   Thymus                                  |                   +                                +        +  +        +|             
 _____________________________________________________________________________________________________________________|             
 INTEGUMENTARY SYSTEM                      |                                                                          |             
                                           |__________________________________________________________________________|             
   Mammary Gland                           |                   +                                +        +  +        +|             
                                           |__________________________________________________________________________|             
   Skin                                    |                   +                                +        +  +        +|             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM                    |                                                                          |             
                                           |__________________________________________________________________________|             
   Bone                                    |                   +                                +        +  +        +|             
 _____________________________________________________________________________________________________________________|             
 NERVOUS SYSTEM                            |                                                                          |             
                                           |__________________________________________________________________________|             
   Brain                                   |                   +                                +        +  +        +|             
                                           |__________________________________________________________________________|             
   Peripheral Nerve                        |                   +                                +        +  +        +|             
                                           |__________________________________________________________________________|             
   Spinal Cord                             |                   +                                +        +  +        +|             
 _____________________________________________________________________________________________________________________|             
 RESPIRATORY SYSTEM                        |                                                                          |             
                                           |__________________________________________________________________________|             
   Larynx                                  |                   +                                +        +  +        +|             
                                           |__________________________________________________________________________|             
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Nose                                    |                   +                                +        +  +        +|             
                                           |__________________________________________________________________________|             
 __________________________________________|__________________________________________________________________________|             
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page  36                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 3| 3| 3| 3| 3| 3| 1| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 1| 3| 3| 1| 1| 3| 3| 1|             
                             DAY ON TEST   | 6| 6| 6| 6| 6| 6| 8| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 8| 6| 6| 8| 8| 6| 6| 8|             
                                           | 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|             
 __________________________________________|__________________________________________________________________________|             
                                           | 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|             
   FISCHER 344 RATS 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   | 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|             
    2200 PPM                               | 6| 6| 6| 6| 6| 6| 6| 6| 6| 7| 7| 7| 7| 7| 7| 7| 7| 7| 7| 8| 8| 8| 8| 8| 8|             
                                           | 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                 |                                                                          |             
                                           |                                                                          |             
   Trachea                                 |                   +                                +        +  +        +|             
 _____________________________________________________________________________________________________________________|             
 SPECIAL SENSES SYSTEM                     |                                                                          |             
                                           |__________________________________________________________________________|             
   Eye                                     |                   +                                +        +  +  +     +|             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM                            |                                                                          |             
                                           |__________________________________________________________________________|             
   Kidney                                  |    +        +     +        +                       +  +     +  +        +|             
                                           |__________________________________________________________________________|             
   Urinary Bladder                         |                   +                    +        +  +     +  +  +  +  +  +|             
 __________________________________________|__________________________________________________________________________|             
 SYSTEMIC LESIONS                          |                                                                          |             
                                            __________________________________________________________________________|             
   Multiple Organs                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Mesothelioma NOS                     |                                                                   X      |             
 __________________________________________|__________________________________________________________________________|             
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page  37                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 3| 3| 3| 3| 1| 1| 3| 1| 3| 1| 3| 3| 3| 1| 3|                             |            |
                             DAY ON TEST   | 6| 6| 6| 6| 8| 8| 6| 8| 6| 8| 6| 6| 6| 8| 6|                             |            |
                                           | 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6|                             |            |
 __________________________________________|__________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|                             |     O      |
   FISCHER 344 RATS MALE                   | 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| 2|                             |     A      |
    2200 PPM                               | 8| 8| 8| 8| 9| 9| 9| 9| 9| 9| 9| 9| 9| 9| 0|                             |     L      |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|                             |            |
 _____________________________________________________________________________________________________________________|____________|
 ALIMENTARY SYSTEM                         |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Esophagus                               |             +  +     +     +           +                                 |  10        |
                                           |__________________________________________________________________________|____________|
   Intestine Large, Colon                  |             +  +     +     +           +                                 |  10        |
                                           |__________________________________________________________________________|____________|
   Intestine Large, Rectum                 |             +  +     +     +           +                                 |  10        |
                                           |__________________________________________________________________________|____________|
   Intestine Large, Cecum                  |             +  +     +     +           +                                 |  10        |
                                           |__________________________________________________________________________|____________|
   Intestine Small, Duodenum               |             +  +     +     +           +                                 |  10        |
                                           |__________________________________________________________________________|____________|
   Intestine Small, Jejunum                |             +  +     +     +           +                                 |  10        |
                                           |__________________________________________________________________________|____________|
   Intestine Small, Ileum                  |             +  +     +     +           +                                 |  10        |
                                           |__________________________________________________________________________|____________|
   Liver                                   |             +  +     +     +     +     +                                 |  17        |
                                           |__________________________________________________________________________|____________|
   Mesentery                               |                                                                          |   2        |
                                           |__________________________________________________________________________|____________|
   Pancreas                                |             +  +     +     +           +                                 |  10        |
                                           |__________________________________________________________________________|____________|
   Pharynx                                 |             +  +     +     +           +                                 |  10        |
                                           |__________________________________________________________________________|____________|
   Salivary Glands                         |             +  +     +     +           +                                 |  10        |
                                           |__________________________________________________________________________|____________|
   Stomach, Forestomach                    |             +  +     +     +           +                                 |  10        |
                                           |__________________________________________________________________________|____________|
   Stomach, Glandular                      |             +  +     +     +           +                                 |  10        |
 _____________________________________________________________________________________________________________________|            |
 CARDIOVASCULAR SYSTEM                     |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Blood Vessel                            |             +  +     +     +           +                                 |  10        |
                                           |__________________________________________________________________________|____________|
 _____________________________________________________________________________________________________________________|____________|
                                                                                                                                    
                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  
                                                                                                                                    
                                                                                                                                    
                                                             Page  38                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 3| 3| 3| 3| 1| 1| 3| 1| 3| 1| 3| 3| 3| 1| 3|                             |            |
                             DAY ON TEST   | 6| 6| 6| 6| 8| 8| 6| 8| 6| 8| 6| 6| 6| 8| 6|                             |            |
                                           | 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6|                             |            |
 __________________________________________|__________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|                             |     O      |
   FISCHER 344 RATS MALE                   | 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| 2|                             |     A      |
    2200 PPM                               | 8| 8| 8| 8| 9| 9| 9| 9| 9| 9| 9| 9| 9| 9| 0|                             |     L      |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|                             |            |
 _____________________________________________________________________________________________________________________|____________|
 CARDIOVASCULAR SYSTEM - cont              |                                                                          |            |
                                           |                                                                          |            |
   Heart                                   |             +  +     +     +           +                                 |  10        |
 _____________________________________________________________________________________________________________________|            |
 ENDOCRINE SYSTEM                          |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Adrenal Cortex                          |             +  +     +     +           +                                 |  10        |
                                           |__________________________________________________________________________|____________|
   Adrenal Medulla                         |             +  +     +     +           +                                 |  10        |
                                           |__________________________________________________________________________|____________|
   Islets, Pancreatic                      |             +  +     +     +           +                                 |  10        |
                                           |__________________________________________________________________________|____________|
   Parathyroid Gland                       |             +  +     +     +           +                                 |  10        |
                                           |__________________________________________________________________________|____________|
   Pituitary Gland                         |             +  +  +  +     +           +                                 |  14        |
      Adenoma                              |                   X                                                      |          3 |
                                           |__________________________________________________________________________|____________|
   Thyroid Gland                           |             +  +     +     +           +                                 |  10        |
 _____________________________________________________________________________________________________________________|            |
 GENERAL BODY SYSTEM                       |                                                                          |            |
    None                                   |                                                                          |            |
 _____________________________________________________________________________________________________________________|            |
 GENITAL SYSTEM                            |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Epididymis                              |             +  +     +     +           +                                 |  11        |
      Mesothelioma NOS                     |                                                                          |          1 |
                                           |__________________________________________________________________________|____________|
   Preputial Gland                         |             +  +     +     +           +                                 |  10        |
                                           |__________________________________________________________________________|____________|
   Prostate                                |             +  +     +     +           +                                 |  10        |
                                           |__________________________________________________________________________|____________|
   Seminal Vesicle                         |             +  +     +     +           +                                 |  10        |
                                           |__________________________________________________________________________|____________|
   Testes                                  | +  +  +  +  +  +     +  +  +  +  +  +  +  +                              |  39        |
 _____________________________________________________________________________________________________________________|____________|
                                                                                                                                    
                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  
                                                                                                                                    
                                                                                                                                    
                                                             Page  39                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 3| 3| 3| 3| 1| 1| 3| 1| 3| 1| 3| 3| 3| 1| 3|                             |            |
                             DAY ON TEST   | 6| 6| 6| 6| 8| 8| 6| 8| 6| 8| 6| 6| 6| 8| 6|                             |            |
                                           | 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6|                             |            |
 __________________________________________|__________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|                             |     O      |
   FISCHER 344 RATS MALE                   | 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| 2|                             |     A      |
    2200 PPM                               | 8| 8| 8| 8| 9| 9| 9| 9| 9| 9| 9| 9| 9| 9| 0|                             |     L      |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|                             |            |
 _____________________________________________________________________________________________________________________|____________|
 GENITAL SYSTEM - cont                     |                                                                          |            |
                                           |                                                                          |            |
      Interstitial Cell, Adenoma           |       X  X                    X     X                                    |          8 |
 _____________________________________________________________________________________________________________________|            |
 HEMATOPOIETIC SYSTEM                      |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Bone Marrow                             |             +  +     +     +           +                                 |  10        |
                                           |__________________________________________________________________________|____________|
   Lymph Node, Bronchial                   |             +  +     +     +           +                                 |  11        |
                                           |__________________________________________________________________________|____________|
   Lymph Node, Mandibular                  |             +  +     +     +           +                                 |  10        |
                                           |__________________________________________________________________________|____________|
   Lymph Node, Mesenteric                  |             +  +     +     +           +                                 |  10        |
                                           |__________________________________________________________________________|____________|
   Lymph Node, Mediastinal                 |             +  +     +     +           +                                 |  10        |
                                           |__________________________________________________________________________|____________|
   Spleen                                  |             +  +     +     +     +     +                                 |  13        |
                                           |__________________________________________________________________________|____________|
   Thymus                                  |             +  +     +     +           +                                 |  10        |
 _____________________________________________________________________________________________________________________|            |
 INTEGUMENTARY SYSTEM                      |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Mammary Gland                           |             +  +     +     +           +                                 |  10        |
                                           |__________________________________________________________________________|____________|
   Skin                                    |             +  +     +     +           +                                 |  10        |
 _____________________________________________________________________________________________________________________|            |
 MUSCULOSKELETAL SYSTEM                    |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Bone                                    |             +  +     +     +           +                                 |  10        |
 _____________________________________________________________________________________________________________________|            |
 NERVOUS SYSTEM                            |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Brain                                   |             +  +     +     +           +                                 |  10        |
                                           |__________________________________________________________________________|____________|
 _____________________________________________________________________________________________________________________|____________|
                                                                                                                                    
                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  
                                                                                                                                    
                                                                                                                                    
                                                             Page  40                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 3| 3| 3| 3| 1| 1| 3| 1| 3| 1| 3| 3| 3| 1| 3|                             |            |
                             DAY ON TEST   | 6| 6| 6| 6| 8| 8| 6| 8| 6| 8| 6| 6| 6| 8| 6|                             |            |
                                           | 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6|                             |            |
 __________________________________________|__________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|                             |     O      |
   FISCHER 344 RATS MALE                   | 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| 2|                             |     A      |
    2200 PPM                               | 8| 8| 8| 8| 9| 9| 9| 9| 9| 9| 9| 9| 9| 9| 0|                             |     L      |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|                             |            |
 _____________________________________________________________________________________________________________________|____________|
 NERVOUS SYSTEM - cont                     |                                                                          |            |
                                           |                                                                          |            |
   Peripheral Nerve                        |             +  +     +     +           +                                 |  10        |
                                           |__________________________________________________________________________|____________|
   Spinal Cord                             |             +  +     +     +           +                                 |  10        |
 _____________________________________________________________________________________________________________________|            |
 RESPIRATORY SYSTEM                        |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Larynx                                  |             +  +     +     +           +                                 |  10        |
                                           |__________________________________________________________________________|____________|
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Nose                                    |             +  +     +     +           +                                 |  10        |
                                           |__________________________________________________________________________|____________|
   Trachea                                 |             +  +     +     +           +                                 |  10        |
 _____________________________________________________________________________________________________________________|            |
 SPECIAL SENSES SYSTEM                     |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Eye                                     |             +  +     +     +           +                                 |  11        |
 _____________________________________________________________________________________________________________________|            |
 URINARY SYSTEM                            |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Kidney                                  |             +  +  +  +  +  +           +                                 |  16        |
                                           |__________________________________________________________________________|____________|
   Urinary Bladder                         | +        +  +  +     +     +           +                                 |  17        |
 __________________________________________________________________________________________________________________________________ 
 SYSTEMIC LESIONS                          |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Multiple Organs                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
      Mesothelioma NOS                     |                                                                          |          1 |
 __________________________________________________________________________________________________________________________________ 
                                                                                                                                    
                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page  41                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 3| 1| 1| 3| 3| 3| 3| 3| 3| 1| 3| 3| 3| 1| 3| 3| 3| 3| 3| 1| 3| 3| 1| 3| 3|             
                             DAY ON TEST   | 6| 8| 8| 6| 6| 6| 6| 6| 6| 8| 6| 6| 6| 8| 6| 6| 6| 6| 6| 8| 6| 6| 8| 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| 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|             
   FISCHER 344 RATS 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|             
    7000 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                               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Intestine Large, Colon                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Intestine Large, Cecum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Intestine Small, Duodenum               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Intestine Small, Jejunum                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Intestine Small, Ileum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Mesentery                               |                                                                   +      |             
                                           |__________________________________________________________________________|             
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Pharynx                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Palate, Papilloma                    |                                  X                                       |             
                                           |__________________________________________________________________________|             
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 CARDIOVASCULAR SYSTEM                     |                                                                          |             
                                           |__________________________________________________________________________|             
   Blood Vessel                            | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 ENDOCRINE SYSTEM                          |                                                                          |             
 __________________________________________|__________________________________________________________________________|             
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page  42                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 3| 1| 1| 3| 3| 3| 3| 3| 3| 1| 3| 3| 3| 1| 3| 3| 3| 3| 3| 1| 3| 3| 1| 3| 3|             
                             DAY ON TEST   | 6| 8| 8| 6| 6| 6| 6| 6| 6| 8| 6| 6| 6| 8| 6| 6| 6| 6| 6| 8| 6| 6| 8| 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| 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|             
   FISCHER 344 RATS 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|             
    7000 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                   |                                                                          |             
                                           |                                                                          |             
                                           |__________________________________________________________________________|             
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Parathyroid Gland                       | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Pituitary Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Adenoma                              |             X  X                    X     X           X                 X|             
                                           |__________________________________________________________________________|             
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 GENERAL BODY SYSTEM                       |                                                                          |             
    None                                   |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 GENITAL SYSTEM                            |                                                                          |             
                                           |__________________________________________________________________________|             
   Epididymis                              | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Mesothelioma Benign                  |                                                                          |             
                                           |__________________________________________________________________________|             
   Preputial Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Prostate                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Seminal Vesicle                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Testes                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Interstitial Cell, Adenoma           | X        X                       X                    X     X  X         |             
      Interstitial Cell, Adenoma, Multiple |                                                                          |             
 _____________________________________________________________________________________________________________________|             
 HEMATOPOIETIC SYSTEM                      |                                                                          |             
                                           |__________________________________________________________________________|             
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
 __________________________________________|__________________________________________________________________________|             
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page  43                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 3| 1| 1| 3| 3| 3| 3| 3| 3| 1| 3| 3| 3| 1| 3| 3| 3| 3| 3| 1| 3| 3| 1| 3| 3|             
                             DAY ON TEST   | 6| 8| 8| 6| 6| 6| 6| 6| 6| 8| 6| 6| 6| 8| 6| 6| 6| 6| 6| 8| 6| 6| 8| 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| 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|             
   FISCHER 344 RATS 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|             
    7000 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, Bronchial                   | +  +  +  +  +  +  +  +  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Lymph Node, Mandibular                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Lymph Node, Mediastinal                 | +  M  M  M  +  +  +  M  +  +  +  M  +  +  +  +  +  +  +  M  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Thymus                                  | +  +  +  +  +  M  +  +  M  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 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                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 MUSCULOSKELETAL SYSTEM                    |                                                                          |             
                                           |__________________________________________________________________________|             
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 NERVOUS SYSTEM                            |                                                                          |             
                                           |__________________________________________________________________________|             
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Peripheral Nerve                        | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Spinal Cord                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 RESPIRATORY SYSTEM                        |                                                                          |             
                                           |__________________________________________________________________________|             
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Alveolar/Bronchiolar Adenoma         |                X                                                         |             
 __________________________________________|__________________________________________________________________________|             
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page  44                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 _____________________________________________________________________________________________________________________              
                                           | 3| 1| 1| 3| 3| 3| 3| 3| 3| 1| 3| 3| 3| 1| 3| 3| 3| 3| 3| 1| 3| 3| 1| 3| 3|             
                             DAY ON TEST   | 6| 8| 8| 6| 6| 6| 6| 6| 6| 8| 6| 6| 6| 8| 6| 6| 6| 6| 6| 8| 6| 6| 8| 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| 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|             
   FISCHER 344 RATS 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|             
    7000 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|             
 __________________________________________|__________________________________________________________________________|             
 RESPIRATORY SYSTEM - cont                 |                                                                          |             
                                           |                                                                          |             
                                           |__________________________________________________________________________|             
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 _____________________________________________________________________________________________________________________|             
 SPECIAL SENSES SYSTEM                     |                                                                          |             
                                           |__________________________________________________________________________|             
   Eye                                     | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Harderian Gland                         |             +                                      +           +         |             
 _____________________________________________________________________________________________________________________|             
 URINARY SYSTEM                            |                                                                          |             
                                           |__________________________________________________________________________|             
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
                                           |__________________________________________________________________________|             
   Urinary Bladder                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
 __________________________________________|__________________________________________________________________________|             
 SYSTEMIC LESIONS                          |                                                                          |             
                                            __________________________________________________________________________|             
   Multiple Organs                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +  +|             
      Mesothelioma Benign                  |                                                                          |             
 __________________________________________|__________________________________________________________________________|             
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                             Page  45                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 1| 3| 3| 3| 3| 1| 1| 3| 3| 3| 3| 3| 3| 3| 1|                             |            |
                             DAY ON TEST   | 8| 6| 6| 6| 6| 8| 8| 6| 6| 6| 6| 6| 6| 6| 8|                             |            |
                                           | 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6|                             |            |
 __________________________________________|__________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|                             |     O      |
   FISCHER 344 RATS MALE                   | 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|                             |     A      |
    7000 PPM                               | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4|                             |     L      |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|                             |            |
 _____________________________________________________________________________________________________________________|____________|
 ALIMENTARY SYSTEM                         |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Esophagus                               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Intestine Large, Colon                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Intestine Large, Rectum                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Intestine Large, Cecum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Intestine Small, Duodenum               | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Intestine Small, Jejunum                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Intestine Small, Ileum                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Liver                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Mesentery                               |                                                                          |   1        |
                                           |__________________________________________________________________________|____________|
   Pancreas                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Pharynx                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
      Palate, Papilloma                    |                                                                          |          1 |
                                           |__________________________________________________________________________|____________|
   Salivary Glands                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Stomach, Forestomach                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Stomach, Glandular                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
 _____________________________________________________________________________________________________________________|            |
 CARDIOVASCULAR SYSTEM                     |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Blood Vessel                            | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
 _____________________________________________________________________________________________________________________|____________|
                                                                                                                                    
                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  
                                                                                                                                    
                                                                                                                                    
                                                             Page  46                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 1| 3| 3| 3| 3| 1| 1| 3| 3| 3| 3| 3| 3| 3| 1|                             |            |
                             DAY ON TEST   | 8| 6| 6| 6| 6| 8| 8| 6| 6| 6| 6| 6| 6| 6| 8|                             |            |
                                           | 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6|                             |            |
 __________________________________________|__________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|                             |     O      |
   FISCHER 344 RATS MALE                   | 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|                             |     A      |
    7000 PPM                               | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4|                             |     L      |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|                             |            |
 _____________________________________________________________________________________________________________________|____________|
 CARDIOVASCULAR SYSTEM - cont              |                                                                          |            |
                                           |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Heart                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
 _____________________________________________________________________________________________________________________|            |
 ENDOCRINE SYSTEM                          |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Adrenal Cortex                          | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Adrenal Medulla                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Islets, Pancreatic                      | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Parathyroid Gland                       | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Pituitary Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
      Adenoma                              |       X              X                                                   |          8 |
                                           |__________________________________________________________________________|____________|
   Thyroid Gland                           | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
 _____________________________________________________________________________________________________________________|            |
 GENERAL BODY SYSTEM                       |                                                                          |            |
    None                                   |                                                                          |            |
 _____________________________________________________________________________________________________________________|            |
 GENITAL SYSTEM                            |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Epididymis                              | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
      Mesothelioma Benign                  |                                     X                                    |          1 |
                                           |__________________________________________________________________________|____________|
   Preputial Gland                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Prostate                                | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Seminal Vesicle                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
 _____________________________________________________________________________________________________________________|____________|
                                                                                                                                    
                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  
                                                                                                                                    
                                                                                                                                    
                                                             Page  47                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 1| 3| 3| 3| 3| 1| 1| 3| 3| 3| 3| 3| 3| 3| 1|                             |            |
                             DAY ON TEST   | 8| 6| 6| 6| 6| 8| 8| 6| 6| 6| 6| 6| 6| 6| 8|                             |            |
                                           | 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6|                             |            |
 __________________________________________|__________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|                             |     O      |
   FISCHER 344 RATS MALE                   | 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|                             |     A      |
    7000 PPM                               | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4|                             |     L      |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|                             |            |
 _____________________________________________________________________________________________________________________|____________|
 GENITAL SYSTEM - cont                     |                                                                          |            |
                                           |                                                                          |            |
   Testes                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
      Interstitial Cell, Adenoma           |                      X        X                                          |          8 |
      Interstitial Cell, Adenoma, Multiple |                                     X                                    |          1 |
 _____________________________________________________________________________________________________________________|            |
 HEMATOPOIETIC SYSTEM                      |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Bone Marrow                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Lymph Node, Bronchial                   | +  +  +  M  +  +  +  M  +  +  +  +  +  +  +                              |  37        |
                                           |__________________________________________________________________________|____________|
   Lymph Node, Mandibular                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Lymph Node, Mesenteric                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Lymph Node, Mediastinal                 | +  +  M  +  +  M  +  +  +  M  M  +  +  +  +                              |  30        |
                                           |__________________________________________________________________________|____________|
   Spleen                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Thymus                                  | +  M  +  +  +  +  +  M  +  +  +  +  +  +  +                              |  36        |
 _____________________________________________________________________________________________________________________|            |
 INTEGUMENTARY SYSTEM                      |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Mammary Gland                           | M  M  M  M  M  M  +  M  M  M  M  M  M  M  M                              |   3        |
                                           |__________________________________________________________________________|____________|
   Skin                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
 _____________________________________________________________________________________________________________________|            |
 MUSCULOSKELETAL SYSTEM                    |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Bone                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
 _____________________________________________________________________________________________________________________|            |
 NERVOUS SYSTEM                            |                                                                          |            |
                                           |__________________________________________________________________________|____________|
 _____________________________________________________________________________________________________________________|____________|
                                                                                                                                    
                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  
                                                                                                                                    
                                                                                                                                    
                                                             Page  48                                                               
                                                                                                                                   
NTP Experiment-Test: 05135-05                        NEOPLASMS BY INDIVIDUAL ANIMAL                               Report: PEIRPT04  
Study Type: SIX MONTH EXPOS.                                     ISOPRENE                                         Date: 10/15/04    
Route: RESPIRATORY EXPOSURE WHOLE BODY                                                                            Time: 13:14:18    
                                                                                                                                    
 __________________________________________________________________________________________________________________________________ 
                                           | 1| 3| 3| 3| 3| 1| 1| 3| 3| 3| 3| 3| 3| 3| 1|                             |            |
                             DAY ON TEST   | 8| 6| 6| 6| 6| 8| 8| 6| 6| 6| 6| 6| 6| 6| 8|                             |            |
                                           | 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6| 6|                             |            |
 __________________________________________|__________________________________________________________________________|     T (*)  |
                                           | 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0| 0|                             |     O      |
   FISCHER 344 RATS MALE                   | 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|                             |     A      |
    7000 PPM                               | 2| 2| 2| 2| 3| 3| 3| 3| 3| 3| 3| 3| 3| 3| 4|                             |     L      |
                                           | 6| 7| 8| 9| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0|                             |            |
 _____________________________________________________________________________________________________________________|____________|
 NERVOUS SYSTEM - cont                     |                                                                          |            |
                                           |                                                                          |            |
   Brain                                   | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Peripheral Nerve                        | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Spinal Cord                             | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
 _____________________________________________________________________________________________________________________|            |
 RESPIRATORY SYSTEM                        |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Larynx                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Lung                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
      Alveolar/Bronchiolar Adenoma         |                                                                          |          1 |
                                           |__________________________________________________________________________|____________|
   Nose                                    | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Trachea                                 | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
 _____________________________________________________________________________________________________________________|            |
 SPECIAL SENSES SYSTEM                     |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Eye                                     | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Harderian Gland                         |                +                    +     +                              |   6        |
 _____________________________________________________________________________________________________________________|            |
 URINARY SYSTEM                            |                                                                          |            |
                                           |__________________________________________________________________________|____________|
   Kidney                                  | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
                                           |__________________________________________________________________________|____________|
   Urinary Bladder                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
 __________________________________________________________________________________________________________________________________ 
 SYSTEMIC LESIONS                          |                                                                          |            |
                                            __________________________________________________________________________|____________|
   Multiple Organs                         | +  +  +  +  +  +  +  +  +  +  +  +  +  +  +                              |  40        |
      Mesothelioma Benign                  |                                     X                                    |          1 |
 __________________________________________________________________________________________________________________________________ 
                                                                                                                                    
                         * : Total animals with tissue examined microscopically; total animals with tumor                           
                         + : Tissue examined microscopically                      M : Missing tissue                                
                         X : Lesion present                                       A : Autolysis precludes evaluation                
                         I : Insufficient tissue                              BLANK : Not examined microscopically                  
                                                                                                                                    
                                                                                                                                    
                                                             Page  49                                                               
                                                                                                                                   
                                  ------------------------------------------------------------                                      
                                  ----------              END OF REPORT             ----------                                      
                                  ------------------------------------------------------------