National Toxicology Program

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TDMS Study 97006-02 Pathology Tables

NTP                                    STATISTICAL ANALYSIS OF NON-NEOPLASTIC LESIONS                          REPORT: PEIRPT10     
LAB: Battelle Northwest                                  METHYL ISOBUTYL KETONE                                DATE: 04/29/04       
EXPERIMENT: 97006 TEST: 02                                                                                     TIME: 07:52:12       
TEST TYPE:  CHRONIC                             CAGES FROM 0000 TO LAST CAGE                                   PAGE:       1        
CONT: N01-ES-05452                              ROUTE: RESPIRATORY EXPOSURE WHOLE BODY                         NTP C#: C97006       
PATHOLOGIST: GRUMBEIN, SONDRA                                                                                  CAS: 108-10-1        
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                                                            FINAL#1 MICE                                                            
                                                                                                                                    
                                                                                                                                    
               REASONS FOR REMOVAL:    ALL                                                                                          
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
               REMOVAL DATE RANGE:     ALL                                                                                          
                                                                                                                                    
               TREATMENT GROUPS:       INCLUDE ALL                                                                                  
                                                                                                                                   
NTP                                    STATISTICAL ANALYSIS OF NON-NEOPLASTIC LESIONS                          REPORT: PEIRPT10     
LAB: Battelle Northwest                                  METHYL ISOBUTYL KETONE                                DATE: 04/29/04       
EXPERIMENT: 97006 TEST: 02                                                                                     TIME: 07:52:12       
TEST TYPE:  CHRONIC                             CAGES FROM 0000 TO LAST CAGE                                                        
CONT: N01-ES-05452                              ROUTE: RESPIRATORY EXPOSURE WHOLE BODY                         NTP C#: C97006       
PATHOLOGIST: GRUMBEIN, SONDRA                                                                                  CAS: 108-10-1        
                                                                                                                                    
                                                                                                                                    
SUMMARY OF STATISTICALLY SIGNIFICANT (P<=.05) RESULTS                                                                               
IN THE ANALYSIS OF                 METHYL ISOBUTYL KETONE                                                                           
===============================================================                                                                     
Male Mice                                                                                                                           
------------                                                                                                                        
Organ                                 Morphology                                                                                    
-----                                 ----------                                                                                    
Adrenal Cortex                         Hypertrophy                                                                                  
Brain                                  Necrosis                                                                                     
Heart                                  Cardiomyopathy                                                                               
Heart: Artery                          Inflammation Chronic                                                                         
Liver                                  Clear Cell Focus                                                                             
                                       Eosinophilic Focus                                                                           
Mesentery: Fat                         Necrosis                                                                                     
===============================================================                                                                     
Female Mice                                                                                                                         
------------                                                                                                                        
Organ                                  Morphology                                                                                   
-----                                  ----------                                                                                   
Liver                                  Eosinophilic Focus                                                                           
Nose                                   Inflammation                                                                                 
Nose: Olfactory Epithelium             Degeneration Hyaline                                                                         
Nose: Respiratory Epithelium           Degeneration Hyaline                                                                         
Pancreas                               Atrophy                                                                                      
Stomach, Forestomach: Artery           Inflammation Chronic                                                                         
Stomach, Glandular: Artery             Inflammation Chronic                                                                         
===============================================================                                                                     
                                                                                                                                   
       Date:  04/29/04                           EXPERIMENT: 97006 TEST: 02                                            Page 1       
Statistical Analysis of Non-neoplastic Lesions in        Mice(B6C3F1)  -                  METHYL ISOBUTYL KETONE                    
                                         Terminal Sacrifice at 105 weeks                                                            
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Adrenal Cortex                                                                                                                   | 
|     Hyperplasia                                                                                                                 | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     13/50 (26%)  18/50 (36%)  13/49 (27%)  9/50 (18%)  |4/50 (8%)    3/50 (6%)    1/50 (2%)    2/50 (4%)    | 
|POLY-3 RATE (b)    |     13/46.97     18/47.79     13/43.29     9/45.81     |4/44.99      3/46.04      1/45.87      2/46.46      | 
|POLY-3 PERCENT (g) |     27.7%        37.7%        30.0%        19.7%       |8.9%         6.5%         2.2%         4.3%         | 
|TERMINAL (d)       |     12/40 (30%)  16/42 (38%)  11/35 (31%)  8/37 (22%)  |4/35 (11%)   2/37 (5%)    1/39 (3%)    2/38 (5%)    | 
|FIRST INCIDENCE    |     598          680          471          593         |731 (T)      687          731 (T)      731 (T)      | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     P=0.173N     P=0.242      P=0.439      P=0.299N    |P=0.194N     P=0.472N     P=0.148N     P=0.299N     | 
|POLY 3             |     P=0.122N     P=0.206      P=0.494      P=0.253N    |P=0.215N     P=0.487N     P=0.173N     P=0.323N     | 
|POLY 1.5           |     P=0.115N     P=0.200      P=0.511      P=0.246N    |P=0.217N     P=0.493N     P=0.175N     P=0.327N     | 
|POLY 6             |     P=0.130N     P=0.219      P=0.484      P=0.259N    |P=0.212N     P=0.483N     P=0.170N     P=0.315N     | 
|LOGISTIC REGRESSION|     P=0.124N     P=0.224      P=0.507      P=0.257N    |P=0.199N     P=0.487N     P=0.148N     P=0.299N     | 
|COCH-ARM / FISHERS |     P=0.103N     P=0.194      P=0.567      P=0.235N    |P=0.221N     P=0.500N     P=0.181N     P=0.339N     | 
|ORDER RESTRICTED   |     P=0.122N     (e)          (e)          (e)         |P=0.184N     (e)          (e)          (e)          | 
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Adrenal Cortex                                                                                                                   | 
|     Hypertrophy                                                                                                                 | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     26/50 (52%)  30/50 (60%)  26/49 (53%)  14/50 (28%) |3/50 (6%)    0/50 (0%)    3/50 (6%)    3/50 (6%)    | 
|POLY-3 RATE (b)    |     26/46.97     30/48.16     26/44.78     14/45.54    |3/44.99      0/45.87      3/45.87      3/46.86      | 
|POLY-3 PERCENT (g) |     55.4%        62.3%        58.1%        30.7%       |6.7%         0.0%         6.5%         6.4%         | 
|TERMINAL (d)       |     25/40 (63%)  27/42 (64%)  21/35 (60%)  13/37 (35%) |3/35 (9%)    0/37 (0%)    3/39 (8%)    2/38 (5%)    | 
|FIRST INCIDENCE    |     598          661          471          678         |731 (T)      ---          731 (T)      617          | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     P=0.011N*    P=0.367      P=0.314      P=0.020N*   |P=0.418      P=0.111N     P=0.613N     P=0.627N     | 
|POLY 3             |     P=0.003N**   P=0.314      P=0.480      P=0.012N*   |P=0.400      P=0.115N     P=0.653N     P=0.643N     | 
|POLY 1.5           |     P=0.003N**   P=0.293      P=0.479      P=0.012N*   |P=0.396      P=0.117N     P=0.657N     P=0.650N     | 
|POLY 6             |     P=0.004N**   P=0.356      P=0.498      P=0.012N*   |P=0.409      P=0.114N     P=0.650N     P=0.633N     | 
|LOGISTIC REGRESSION|     P=0.005N**   P=0.344      P=0.402      P=0.014N*   |P=0.399      (e)          P=0.613N     P=0.655N     | 
|COCH-ARM / FISHERS |     P=0.003N**   P=0.273      P=0.538      P=0.012N*   |P=0.387      P=0.121N     P=0.661N     P=0.661N     | 
|ORDER RESTRICTED   |     P=0.003N**   (e)          (e)          (e)         |P=0.383      (e)          (e)          (e)          | 
|=================================================================================================================================| 
                                                                                                                                   
       Date:  04/29/04                           EXPERIMENT: 97006 TEST: 02                                            Page 2       
                     Statistical Analysis of Non-neoplastic Lesions in       Mice(B6C3F1)  -                  METHYL ISOBUTYL KETONE
                                         Terminal Sacrifice at 105 weeks                                                            
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Adrenal Medulla                                                                                                                  | 
|     Hyperplasia                                                                                                                 | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     1/50 (2%)    1/50 (2%)    3/49 (6%)    0/50 (0%)   |2/50 (4%)    2/50 (4%)    1/49 (2%)    0/49 (0%)    | 
|POLY-3 RATE (b)    |     1/46.53      1/47.60      3/41.95      0/45.34     |2/44.99      2/45.87      1/45.18      0/45.46      | 
|POLY-3 PERCENT (g) |     2.2%         2.1%         7.2%         0.0%        |4.5%         4.4%         2.2%         0.0%         | 
|TERMINAL (d)       |     1/40 (3%)    0/42 (0%)    2/35 (6%)    0/37 (0%)   |2/35 (6%)    2/37 (5%)    0/38 (0%)    0/37 (0%)    | 
|FIRST INCIDENCE    |     729 (T)      704          701          ---         |731 (T)      731 (T)      648          ---          | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     P=0.440N     P=0.747N     P=0.263      P=0.516N    |P=0.118N     P=0.675N     P=0.476N     P=0.226N     | 
|POLY 3             |     P=0.425N     P=0.755N     P=0.269      P=0.505N    |P=0.125N     P=0.687N     P=0.499N     P=0.235N     | 
|POLY 1.5           |     P=0.419N     P=0.758N     P=0.276      P=0.503N    |P=0.127N     P=0.690N     P=0.502N     P=0.237N     | 
|POLY 6             |     P=0.432N     P=0.752N     P=0.265      P=0.507N    |P=0.123N     P=0.686N     P=0.495N     P=0.231N     | 
|LOGISTIC REGRESSION|     P=0.427N     P=0.760N     P=0.263      (e)         |P=0.126N     P=0.675N     P=0.506N     (e)          | 
|COCH-ARM / FISHERS |     P=0.410N     P=0.753N     P=0.301      P=0.500N    |P=0.129N     P=0.691N     P=0.508N     P=0.253N     | 
|ORDER RESTRICTED   |     P=0.218N     (e)          (e)          (e)         |P=0.153N     (e)          (e)          (e)          | 
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Brain                                                                                                                            | 
|     Necrosis                                                                                                                    | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     2/50 (4%)    0/50 (0%)    0/50 (0%)    0/50 (0%)   |0/50 (0%)    0/50 (0%)    0/50 (0%)    0/50 (0%)    | 
|POLY-3 RATE (b)    |     2/47.33      0/47.50      0/42.28      0/45.34     |0/44.99      0/45.87      0/45.87      0/46.46      | 
|POLY-3 PERCENT (g) |     4.2%         0.0%         0.0%         0.0%        |0.0%         0.0%         0.0%         0.0%         | 
|TERMINAL (d)       |     0/40 (0%)    0/42 (0%)    0/35 (0%)    0/37 (0%)   |0/35 (0%)    0/37 (0%)    0/39 (0%)    0/38 (0%)    | 
|FIRST INCIDENCE    |     612          ---          ---          ---         |---          ---          ---          ---          | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     P=0.128N     P=0.240N     P=0.276N     P=0.257N    |(e)          (e)          (e)          (e)          | 
|POLY 3             |     P=0.117N     P=0.236N     P=0.263N     P=0.247N    |(e)          (e)          (e)          (e)          | 
|POLY 1.5           |     P=0.116N     P=0.237N     P=0.255N     P=0.243N    |(e)          (e)          (e)          (e)          | 
|POLY 6             |     P=0.118N     P=0.235N     P=0.271N     P=0.251N    |(e)          (e)          (e)          (e)          | 
|LOGISTIC REGRESSION|     P=0.089N     P=0.245N     P=0.163N     P=0.163N    |(e)          (e)          (e)          (e)          | 
|COCH-ARM / FISHERS |     P=0.115N     P=0.247N     P=0.247N     P=0.247N    |(e)          (e)          (e)          (e)          | 
|ORDER RESTRICTED   |     P=0.033N*    (e)          (e)          (e)         |(e)          (e)          (e)          (e)          | 
|=================================================================================================================================| 
                                                                                                                                   
       Date:  04/29/04                           EXPERIMENT: 97006 TEST: 02                                            Page 3       
                     Statistical Analysis of Non-neoplastic Lesions in       Mice(B6C3F1)  -                  METHYL ISOBUTYL KETONE
                                         Terminal Sacrifice at 105 weeks                                                            
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Brain: Meninges                                                                                                                  | 
|     Infiltration Cellular Mononuclear Cell                                                                                      | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     0/50 (0%)    0/50 (0%)    0/50 (0%)    0/50 (0%)   |0/50 (0%)    1/50 (2%)    2/50 (4%)    2/50 (4%)    | 
|POLY-3 RATE (b)    |     0/46.53      0/47.50      0/42.28      0/45.34     |0/44.99      1/45.87      2/45.87      2/46.46      | 
|POLY-3 PERCENT (g) |     0.0%         0.0%         0.0%         0.0%        |0.0%         2.2%         4.4%         4.3%         | 
|TERMINAL (d)       |     0/40 (0%)    0/42 (0%)    0/35 (0%)    0/37 (0%)   |0/35 (0%)    1/37 (3%)    2/39 (5%)    2/38 (5%)    | 
|FIRST INCIDENCE    |     ---          ---          ---          ---         |---          731 (T)      731 (T)      731 (T)      | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     (e)          (e)          (e)          (e)         |P=0.174      P=0.511      P=0.262      P=0.257      | 
|POLY 3             |     (e)          (e)          (e)          (e)         |P=0.169      P=0.504      P=0.242      P=0.244      | 
|POLY 1.5           |     (e)          (e)          (e)          (e)         |P=0.167      P=0.502      P=0.240      P=0.242      | 
|POLY 6             |     (e)          (e)          (e)          (e)         |P=0.174      P=0.505      P=0.243      P=0.248      | 
|LOGISTIC REGRESSION|     (e)          (e)          (e)          (e)         |(e)          P=0.511      P=0.262      P=0.257      | 
|COCH-ARM / FISHERS |     (e)          (e)          (e)          (e)         |P=0.160      P=0.500      P=0.247      P=0.247      | 
|ORDER RESTRICTED   |     (e)          (e)          (e)          (e)         |P=0.158      (e)          (e)          (e)          | 
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Epididymis                                                                                                                       | 
|     Granuloma Sperm                                                                                                             | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     2/50 (4%)    0/50 (0%)    2/50 (4%)    1/50 (2%)   |                                                    | 
|POLY-3 RATE (b)    |     2/46.97      0/47.50      2/42.33      1/45.34     |                                                    | 
|POLY-3 PERCENT (g) |     4.3%         0.0%         4.7%         2.2%        |                                                    | 
|TERMINAL (d)       |     1/40 (3%)    0/42 (0%)    1/35 (3%)    1/37 (3%)   |                                                    | 
|FIRST INCIDENCE    |     598          ---          717          729 (T)     |                                                    | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     P=0.561N     P=0.239N     P=0.642      P=0.525N    |                                                    | 
|POLY 3             |     P=0.546N     P=0.235N     P=0.656      P=0.512N    |                                                    | 
|POLY 1.5           |     P=0.540N     P=0.236N     P=0.667      P=0.507N    |                                                    | 
|POLY 6             |     P=0.553N     P=0.233N     P=0.647      P=0.517N    |                                                    | 
|LOGISTIC REGRESSION|     P=0.532N     P=0.249N     P=0.693      P=0.481N    |                                                    | 
|COCH-ARM / FISHERS |     P=0.531N     P=0.247N     P=0.691N     P=0.500N    |                                                    | 
|ORDER RESTRICTED   |     P=0.431N     (e)          (e)          (e)         |                                                    | 
|=================================================================================================================================| 
                                                                                                                                   
       Date:  04/29/04                           EXPERIMENT: 97006 TEST: 02                                            Page 4       
                     Statistical Analysis of Non-neoplastic Lesions in       Mice(B6C3F1)  -                  METHYL ISOBUTYL KETONE
                                         Terminal Sacrifice at 105 weeks                                                            
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Eye: Cornea                                                                                                                      | 
|     Inflammation Chronic                                                                                                        | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     0/49 (0%)    2/48 (4%)    0/49 (0%)    0/49 (0%)   |1/49 (2%)    1/48 (2%)    3/49 (6%)    2/50 (4%)    | 
|POLY-3 RATE (b)    |     0/46.24      2/45.94      0/41.84      0/44.78     |1/44.41      1/45.52      3/45.40      2/46.46      | 
|POLY-3 PERCENT (g) |     0.0%         4.4%         0.0%         0.0%        |2.3%         2.2%         6.6%         4.3%         | 
|TERMINAL (d)       |     0/40 (0%)    2/42 (5%)    0/35 (0%)    0/37 (0%)   |0/35 (0%)    1/37 (3%)    2/39 (5%)    2/38 (5%)    | 
|FIRST INCIDENCE    |     ---          729 (T)      ---          ---         |715          731 (T)      648          731 (T)      | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     P=0.428N     P=0.249      (e)          (e)         |P=0.352      P=0.751N     P=0.334      P=0.531      | 
|POLY 3             |     P=0.414N     P=0.236      (e)          (e)         |P=0.341      P=0.755N     P=0.313      P=0.516      | 
|POLY 1.5           |     P=0.411N     P=0.234      (e)          (e)         |P=0.339      P=0.757N     P=0.310      P=0.513      | 
|POLY 6             |     P=0.415N     P=0.240      (e)          (e)         |P=0.346      P=0.755N     P=0.316      P=0.519      | 
|LOGISTIC REGRESSION|     (e)          P=0.249      (e)          (e)         |P=0.339      P=0.756N     P=0.306      P=0.523      | 
|COCH-ARM / FISHERS |     P=0.404N     P=0.242      (e)          (e)         |P=0.335      P=0.747      P=0.309      P=0.508      | 
|ORDER RESTRICTED   |     P=0.252N     (e)          (e)          (e)         |P=0.339      (e)          (e)          (e)          | 
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Harderian Gland                                                                                                                  | 
|     Hyperplasia                                                                                                                 | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     3/50 (6%)    4/49 (8%)    1/50 (2%)    2/50 (4%)   |1/49 (2%)    1/49 (2%)    2/49 (4%)    1/50 (2%)    | 
|POLY-3 RATE (b)    |     3/46.53      4/47.54      1/42.28      2/45.34     |1/44.34      1/45.60      2/45.09      1/46.46      | 
|POLY-3 PERCENT (g) |     6.5%         8.4%         2.4%         4.4%        |2.3%         2.2%         4.4%         2.2%         | 
|TERMINAL (d)       |     3/40 (8%)    2/42 (5%)    1/35 (3%)    2/37 (5%)   |1/35 (3%)    0/37 (0%)    2/39 (5%)    1/38 (3%)    | 
|FIRST INCIDENCE    |     729 (T)      493          729 (T)      729 (T)     |731 (T)      710          731 (T)      731 (T)      | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     P=0.334N     P=0.526      P=0.354N     P=0.536N    |P=0.618      P=0.748N     P=0.538      P=0.743N     | 
|POLY 3             |     P=0.310N     P=0.512      P=0.340N     P=0.512N    |P=0.605      P=0.754N     P=0.506      P=0.750N     | 
|POLY 1.5           |     P=0.303N     P=0.502      P=0.331N     P=0.507N    |P=0.603      P=0.757N     P=0.503      P=0.752N     | 
|POLY 6             |     P=0.317N     P=0.526      P=0.348N     P=0.516N    |P=0.610      P=0.753N     P=0.508      P=0.748N     | 
|LOGISTIC REGRESSION|     P=0.293N     P=0.465      P=0.354N     P=0.536N    |P=0.612      P=0.757N     P=0.538      P=0.743N     | 
|COCH-ARM / FISHERS |     P=0.289N     P=0.489      P=0.309N     P=0.500N    |P=0.597      P=0.753N     P=0.500      P=0.747N     | 
|ORDER RESTRICTED   |     P=0.315N     (e)          (e)          (e)         |P=0.594      (e)          (e)          (e)          | 
|=================================================================================================================================| 
                                                                                                                                   
       Date:  04/29/04                           EXPERIMENT: 97006 TEST: 02                                            Page 5       
                     Statistical Analysis of Non-neoplastic Lesions in       Mice(B6C3F1)  -                  METHYL ISOBUTYL KETONE
                                         Terminal Sacrifice at 105 weeks                                                            
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Heart                                                                                                                            | 
|     Cardiomyopathy                                                                                                              | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     10/50 (20%)  8/50 (16%)   2/50 (4%)    10/50 (20%) |3/50 (6%)    6/50 (12%)   5/50 (10%)   3/50 (6%)    | 
|POLY-3 RATE (b)    |     10/46.90     8/47.75      2/42.40      10/46.15    |3/45.12      6/46.27      5/46.02      3/46.51      | 
|POLY-3 PERCENT (g) |     21.3%        16.8%        4.7%         21.7%       |6.7%         13.0%        10.9%        6.5%         | 
|TERMINAL (d)       |     9/40 (23%)   7/42 (17%)   1/35 (3%)    7/37 (19%)  |1/35 (3%)    4/37 (11%)   4/39 (10%)   2/38 (5%)    | 
|FIRST INCIDENCE    |     622          661          698          593         |715          638          695          719          | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     P=0.489      P=0.355N     P=0.029N*    P=0.530     |P=0.399N     P=0.269      P=0.403      P=0.615N     | 
|POLY 3             |     P=0.548      P=0.381N     P=0.022N*    P=0.583     |P=0.429N     P=0.254      P=0.367      P=0.648N     | 
|POLY 1.5           |     P=0.549N     P=0.389N     P=0.019N*    P=0.588     |P=0.435N     P=0.250      P=0.363      P=0.652N     | 
|POLY 6             |     P=0.539      P=0.368N     P=0.024N*    P=0.582     |P=0.419N     P=0.258      P=0.371      P=0.642N     | 
|LOGISTIC REGRESSION|     P=0.543      P=0.376N     P=0.024N*    P=0.581     |P=0.429N     P=0.249      P=0.370      P=0.641N     | 
|COCH-ARM / FISHERS |     P=0.527N     P=0.398N     P=0.014N*    P=0.598N    |P=0.449N     P=0.243      P=0.357      P=0.661N     | 
|ORDER RESTRICTED   |     P=0.241N     (e)          (e)          (e)         |P=0.427N     (e)          (e)          (e)          | 
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Heart                                                                                                                            | 
|     Thrombosis                                                                                                                  | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     2/50 (4%)    0/50 (0%)    3/50 (6%)    1/50 (2%)   |0/50 (0%)    0/50 (0%)    0/50 (0%)    0/50 (0%)    | 
|POLY-3 RATE (b)    |     2/46.63      0/47.50      3/42.56      1/45.68     |0/44.99      0/45.87      0/45.87      0/46.46      | 
|POLY-3 PERCENT (g) |     4.3%         0.0%         7.1%         2.2%        |0.0%         0.0%         0.0%         0.0%         | 
|TERMINAL (d)       |     1/40 (3%)    0/42 (0%)    0/35 (0%)    0/37 (0%)   |0/35 (0%)    0/37 (0%)    0/39 (0%)    0/38 (0%)    | 
|FIRST INCIDENCE    |     704          ---          698          637         |---          ---          ---          ---          | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     P=0.580N     P=0.227N     P=0.451      P=0.514N    |(e)          (e)          (e)          (e)          | 
|POLY 3             |     P=0.570N     P=0.233N     P=0.459      P=0.507N    |(e)          (e)          (e)          (e)          | 
|POLY 1.5           |     P=0.564N     P=0.235N     P=0.470      P=0.505N    |(e)          (e)          (e)          (e)          | 
|POLY 6             |     P=0.575N     P=0.230N     P=0.452      P=0.509N    |(e)          (e)          (e)          (e)          | 
|LOGISTIC REGRESSION|     P=0.555N     P=0.234N     P=0.463      P=0.486N    |(e)          (e)          (e)          (e)          | 
|COCH-ARM / FISHERS |     P=0.556N     P=0.247N     P=0.500      P=0.500N    |(e)          (e)          (e)          (e)          | 
|ORDER RESTRICTED   |     P=0.406      (e)          (e)          (e)         |(e)          (e)          (e)          (e)          | 
|=================================================================================================================================| 
                                                                                                                                   
       Date:  04/29/04                           EXPERIMENT: 97006 TEST: 02                                            Page 6       
                     Statistical Analysis of Non-neoplastic Lesions in       Mice(B6C3F1)  -                  METHYL ISOBUTYL KETONE
                                         Terminal Sacrifice at 105 weeks                                                            
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Heart: Artery                                                                                                                    | 
|     Inflammation Chronic                                                                                                        | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     2/50 (4%)    0/50 (0%)    0/50 (0%)    0/50 (0%)   |1/50 (2%)    2/50 (4%)    0/50 (0%)    0/50 (0%)    | 
|POLY-3 RATE (b)    |     2/46.53      0/47.50      0/42.28      0/45.34     |1/45.86      2/46.20      0/45.87      0/46.46      | 
|POLY-3 PERCENT (g) |     4.3%         0.0%         0.0%         0.0%        |2.2%         4.3%         0.0%         0.0%         | 
|TERMINAL (d)       |     2/40 (5%)    0/42 (0%)    0/35 (0%)    0/37 (0%)   |0/35 (0%)    1/37 (3%)    0/39 (0%)    0/38 (0%)    | 
|FIRST INCIDENCE    |     729 (T)      ---          ---          ---         |368          638          ---          ---          | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     P=0.126N     P=0.228N     P=0.268N     P=0.256N    |P=0.183N     P=0.509      P=0.500N     P=0.500N     | 
|POLY 3             |     P=0.118N     P=0.233N     P=0.259N     P=0.243N    |P=0.187N     P=0.503      P=0.500N     P=0.497N     | 
|POLY 1.5           |     P=0.116N     P=0.235N     P=0.253N     P=0.241N    |P=0.187N     P=0.501      P=0.500N     P=0.498N     | 
|POLY 6             |     P=0.120N     P=0.229N     P=0.264N     P=0.245N    |P=0.185N     P=0.505      P=0.499N     P=0.495N     | 
|LOGISTIC REGRESSION|     P=0.126N     (e)          (e)          (e)         |P=0.205N     P=0.513      P=0.455N     P=0.678N     | 
|COCH-ARM / FISHERS |     P=0.115N     P=0.247N     P=0.247N     P=0.247N    |P=0.188N     P=0.500      P=0.500N     P=0.500N     | 
|ORDER RESTRICTED   |     P=0.031N*    (e)          (e)          (e)         |P=0.167N     (e)          (e)          (e)          | 
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Intestine Small, Jejunum: Peyer's Patch                                                                                          | 
|     Hyperplasia                                                                                                                 | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     1/49 (2%)    1/48 (2%)    2/47 (4%)    0/47 (0%)   |0/48 (0%)    0/47 (0%)    0/47 (0%)    0/48 (0%)    | 
|POLY-3 RATE (b)    |     1/46.24      1/45.94      2/40.28      0/44.13     |0/43.44      0/44.66      0/43.58      0/45.43      | 
|POLY-3 PERCENT (g) |     2.2%         2.2%         5.0%         0.0%        |0.0%         0.0%         0.0%         0.0%         | 
|TERMINAL (d)       |     1/40 (3%)    1/42 (2%)    2/34 (6%)    0/37 (0%)   |0/35 (0%)    0/37 (0%)    0/39 (0%)    0/38 (0%)    | 
|FIRST INCIDENCE    |     729 (T)      729 (T)      729 (T)      ---         |---          ---          ---          ---          | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     P=0.400N     P=0.751N     P=0.443      P=0.516N    |(e)          (e)          (e)          (e)          | 
|POLY 3             |     P=0.383N     P=0.759      P=0.452      P=0.509N    |(e)          (e)          (e)          (e)          | 
|POLY 1.5           |     P=0.381N     P=0.757      P=0.461      P=0.509N    |(e)          (e)          (e)          (e)          | 
|POLY 6             |     P=0.384N     P=0.758N     P=0.447      P=0.509N    |(e)          (e)          (e)          (e)          | 
|LOGISTIC REGRESSION|     P=0.400N     P=0.751N     P=0.443      (e)         |(e)          (e)          (e)          (e)          | 
|COCH-ARM / FISHERS |     P=0.378N     P=0.747      P=0.484      P=0.510N    |(e)          (e)          (e)          (e)          | 
|ORDER RESTRICTED   |     P=0.263N     (e)          (e)          (e)         |(e)          (e)          (e)          (e)          | 
|=================================================================================================================================| 
                                                                                                                                   
       Date:  04/29/04                           EXPERIMENT: 97006 TEST: 02                                            Page 7       
                     Statistical Analysis of Non-neoplastic Lesions in       Mice(B6C3F1)  -                  METHYL ISOBUTYL KETONE
                                         Terminal Sacrifice at 105 weeks                                                            
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Islets, Pancreatic                                                                                                               | 
|     Hyperplasia                                                                                                                 | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     1/49 (2%)    2/50 (4%)    0/49 (0%)    1/50 (2%)   |0/50 (0%)    0/50 (0%)    2/49 (4%)    1/50 (2%)    | 
|POLY-3 RATE (b)    |     1/46.24      2/47.50      0/41.84      1/45.34     |0/44.99      0/45.87      2/45.09      1/46.49      | 
|POLY-3 PERCENT (g) |     2.2%         4.2%         0.0%         2.2%        |0.0%         0.0%         4.4%         2.2%         | 
|TERMINAL (d)       |     1/40 (3%)    2/42 (5%)    0/35 (0%)    1/37 (3%)   |0/35 (0%)    0/37 (0%)    2/39 (5%)    0/38 (0%)    | 
|FIRST INCIDENCE    |     729 (T)      729 (T)      ---          729 (T)     |---          ---          731 (T)      722          | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     P=0.534N     P=0.517      P=0.527N     P=0.744     |P=0.264      (e)          P=0.262      P=0.521      | 
|POLY 3             |     P=0.511N     P=0.509      P=0.520N     P=0.756     |P=0.256      (e)          P=0.238      P=0.507      | 
|POLY 1.5           |     P=0.506N     P=0.508      P=0.514N     P=0.759     |P=0.253      (e)          P=0.236      P=0.504      | 
|POLY 6             |     P=0.516N     P=0.513      P=0.524N     P=0.753     |P=0.262      (e)          P=0.240      P=0.510      | 
|LOGISTIC REGRESSION|     P=0.534N     P=0.517      (e)          P=0.744     |P=0.262      (e)          P=0.262      P=0.508      | 
|COCH-ARM / FISHERS |     P=0.496N     P=0.508      P=0.500N     P=0.747N    |P=0.246      (e)          P=0.242      P=0.500      | 
|ORDER RESTRICTED   |     P=0.399N     (e)          (e)          (e)         |P=0.168      (e)          (e)          (e)          | 
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Kidney                                                                                                                           | 
|     Inflammation                                                                                                                | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     1/50 (2%)    1/50 (2%)    1/49 (2%)    3/50 (6%)   |0/50 (0%)    0/50 (0%)    0/49 (0%)    0/50 (0%)    | 
|POLY-3 RATE (b)    |     1/46.53      1/47.72      1/41.89      3/46.69     |0/44.99      0/45.87      0/45.09      0/46.46      | 
|POLY-3 PERCENT (g) |     2.2%         2.1%         2.4%         6.4%        |0.0%         0.0%         0.0%         0.0%         | 
|TERMINAL (d)       |     1/40 (3%)    0/42 (0%)    0/35 (0%)    1/37 (3%)   |0/35 (0%)    0/37 (0%)    0/39 (0%)    0/38 (0%)    | 
|FIRST INCIDENCE    |     729 (T)      670          717          441         |---          ---          ---          ---          | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     P=0.152      P=0.747N     P=0.734      P=0.292     |(e)          (e)          (e)          (e)          | 
|POLY 3             |     P=0.161      P=0.755N     P=0.737      P=0.307     |(e)          (e)          (e)          (e)          | 
|POLY 1.5           |     P=0.162      P=0.757N     P=0.742      P=0.306     |(e)          (e)          (e)          (e)          | 
|POLY 6             |     P=0.159      P=0.751N     P=0.734      P=0.307     |(e)          (e)          (e)          (e)          | 
|LOGISTIC REGRESSION|     P=0.178      P=0.758      P=0.736      P=0.410     |(e)          (e)          (e)          (e)          | 
|COCH-ARM / FISHERS |     P=0.163      P=0.753N     P=0.747      P=0.309     |(e)          (e)          (e)          (e)          | 
|ORDER RESTRICTED   |     P=0.187      (e)          (e)          (e)         |(e)          (e)          (e)          (e)          | 
|=================================================================================================================================| 
                                                                                                                                   
       Date:  04/29/04                           EXPERIMENT: 97006 TEST: 02                                            Page 8       
                     Statistical Analysis of Non-neoplastic Lesions in       Mice(B6C3F1)  -                  METHYL ISOBUTYL KETONE
                                         Terminal Sacrifice at 105 weeks                                                            
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Kidney                                                                                                                           | 
|     Metaplasia Osseous                                                                                                          | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     2/50 (4%)    2/50 (4%)    3/49 (6%)    1/50 (2%)   |2/50 (4%)    2/50 (4%)    3/49 (6%)    2/50 (4%)    | 
|POLY-3 RATE (b)    |     2/46.53      2/47.50      3/42.52      1/45.34     |2/44.99      2/46.04      3/45.09      2/46.46      | 
|POLY-3 PERCENT (g) |     4.3%         4.2%         7.1%         2.2%        |4.5%         4.3%         6.7%         4.3%         | 
|TERMINAL (d)       |     2/40 (5%)    2/42 (5%)    2/35 (6%)    1/37 (3%)   |2/35 (6%)    1/37 (3%)    3/39 (8%)    2/38 (5%)    | 
|FIRST INCIDENCE    |     729 (T)      729 (T)      501          729 (T)     |731 (T)      687          731 (T)      731 (T)      | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     P=0.445N     P=0.677N     P=0.446      P=0.527N    |P=0.579N     P=0.676N     P=0.550      P=0.665N     | 
|POLY 3             |     P=0.423N     P=0.686N     P=0.459      P=0.509N    |P=0.582      P=0.686N     P=0.501      P=0.682N     | 
|POLY 1.5           |     P=0.416N     P=0.690N     P=0.466      P=0.506N    |P=0.577      P=0.689N     P=0.497      P=0.686N     | 
|POLY 6             |     P=0.430N     P=0.681N     P=0.455      P=0.512N    |P=0.590      P=0.683N     P=0.506      P=0.676N     | 
|LOGISTIC REGRESSION|     P=0.406N     P=0.677N     P=0.504      P=0.527N    |P=0.587N     P=0.688N     P=0.550      P=0.665N     | 
|COCH-ARM / FISHERS |     P=0.405N     P=0.691N     P=0.490      P=0.500N    |P=0.567      P=0.691N     P=0.490      P=0.691N     | 
|ORDER RESTRICTED   |     P=0.393N     (e)          (e)          (e)         |P=0.633      (e)          (e)          (e)          | 
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Kidney                                                                                                                           | 
|     Nephropathy                                                                                                                 | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     41/50 (82%)  45/50 (90%)  40/49 (82%)  43/50 (86%) |22/50 (44%)  28/50 (56%)  26/49 (53%)  27/50 (54%)  | 
|POLY-3 RATE (b)    |     41/48.92     45/49.32     40/45.99     43/48.00    |22/47.49     28/47.81     26/47.01     27/47.51     | 
|POLY-3 PERCENT (g) |     83.8%        91.2%        87.0%        89.6%       |46.3%        58.6%        55.3%        56.8%        | 
|TERMINAL (d)       |     35/40 (88%)  39/42 (93%)  30/35 (86%)  33/37 (89%) |16/35 (46%)  19/37 (51%)  21/39 (54%)  24/38 (63%)  | 
|FIRST INCIDENCE    |     482          493          412          593         |368          598          530          535          | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     P=0.167      P=0.411      P=0.260      P=0.208     |P=0.404      P=0.253      P=0.434      P=0.339      | 
|POLY 3             |     P=0.321      P=0.200      P=0.441      P=0.288     |P=0.248      P=0.159      P=0.251      P=0.205      | 
|POLY 1.5           |     P=0.365      P=0.195      P=0.471      P=0.319     |P=0.254      P=0.154      P=0.243      P=0.209      | 
|POLY 6             |     P=0.312      P=0.216      P=0.443      P=0.287     |P=0.248      P=0.169      P=0.263      P=0.207      | 
|LOGISTIC REGRESSION|     P=0.355      P=0.210      P=0.414      P=0.301     |P=0.274      P=0.162      P=0.245      P=0.226      | 
|COCH-ARM / FISHERS |     P=0.475      P=0.194      P=0.584N     P=0.393     |P=0.255      P=0.159      P=0.242      P=0.212      | 
|ORDER RESTRICTED   |     P=0.287      (e)          (e)          (e)         |P=0.236      (e)          (e)          (e)          | 
|=================================================================================================================================| 
                                                                                                                                   
       Date:  04/29/04                           EXPERIMENT: 97006 TEST: 02                                            Page 9       
                     Statistical Analysis of Non-neoplastic Lesions in       Mice(B6C3F1)  -                  METHYL ISOBUTYL KETONE
                                         Terminal Sacrifice at 105 weeks                                                            
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Kidney: Renal Tubule                                                                                                             | 
|     Hyperplasia                                                                                                                 | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     2/50 (4%)    2/50 (4%)    1/49 (2%)    0/50 (0%)   |0/50 (0%)    0/50 (0%)    0/49 (0%)    1/50 (2%)    | 
|POLY-3 RATE (b)    |     2/46.53      2/47.50      1/42.56      0/45.34     |0/44.99      0/45.87      0/45.09      1/46.46      | 
|POLY-3 PERCENT (g) |     4.3%         4.2%         2.4%         0.0%        |0.0%         0.0%         0.0%         2.2%         | 
|TERMINAL (d)       |     2/40 (5%)    2/42 (5%)    0/35 (0%)    0/37 (0%)   |0/35 (0%)    0/37 (0%)    0/39 (0%)    1/38 (3%)    | 
|FIRST INCIDENCE    |     729 (T)      729 (T)      480          ---         |---          ---          ---          731 (T)      | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     P=0.144N     P=0.677N     P=0.538N     P=0.256N    |P=0.206      (e)          (e)          P=0.516      | 
|POLY 3             |     P=0.134N     P=0.686N     P=0.531N     P=0.243N    |P=0.203      (e)          (e)          P=0.506      | 
|POLY 1.5           |     P=0.132N     P=0.690N     P=0.525N     P=0.241N    |P=0.202      (e)          (e)          P=0.504      | 
|POLY 6             |     P=0.136N     P=0.681N     P=0.534N     P=0.245N    |P=0.205      (e)          (e)          P=0.510      | 
|LOGISTIC REGRESSION|     P=0.117N     P=0.677N     P=0.447N     (e)         |(e)          (e)          (e)          P=0.516      | 
|COCH-ARM / FISHERS |     P=0.126N     P=0.691N     P=0.508N     P=0.247N    |P=0.199      (e)          (e)          P=0.500      | 
|ORDER RESTRICTED   |     P=0.160N     (e)          (e)          (e)         |P=0.126      (e)          (e)          (e)          | 
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Liver                                                                                                                            | 
|     Basophilic Focus                                                                                                            | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     8/50 (16%)   5/50 (10%)   4/50 (8%)    8/50 (16%)  |3/50 (6%)    2/50 (4%)    1/50 (2%)    3/50 (6%)    | 
|POLY-3 RATE (b)    |     8/46.53      5/47.50      4/42.54      8/46.25     |3/44.99      2/46.32      1/45.87      3/46.46      | 
|POLY-3 PERCENT (g) |     17.2%        10.5%        9.4%         17.3%       |6.7%         4.3%         2.2%         6.5%         | 
|TERMINAL (d)       |     8/40 (20%)   5/42 (12%)   3/35 (9%)    5/37 (14%)  |3/35 (9%)    1/37 (3%)    1/39 (3%)    3/38 (8%)    | 
|FIRST INCIDENCE    |     729 (T)      729 (T)      659          601         |731 (T)      598          731 (T)      731 (T)      | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     P=0.403      P=0.243N     P=0.248N     P=0.546     |P=0.583N     P=0.474N     P=0.267N     P=0.625N     | 
|POLY 3             |     P=0.465      P=0.262N     P=0.223N     P=0.603     |P=0.576      P=0.487N     P=0.298N     P=0.647N     | 
|POLY 1.5           |     P=0.471      P=0.269N     P=0.210N     P=0.603     |P=0.574      P=0.492N     P=0.301N     P=0.652N     | 
|POLY 6             |     P=0.461      P=0.252N     P=0.230N     P=0.607     |P=0.581      P=0.482N     P=0.296N     P=0.640N     | 
|LOGISTIC REGRESSION|     P=0.450      P=0.243N     P=0.237N     P=0.591     |P=0.579      P=0.498N     P=0.267N     P=0.625N     | 
|COCH-ARM / FISHERS |     P=0.486      P=0.277N     P=0.178N     P=0.607N    |P=0.569      P=0.500N     P=0.309N     P=0.661N     | 
|ORDER RESTRICTED   |     P=0.393      (e)          (e)          (e)         |P=0.478N     (e)          (e)          (e)          | 
|=================================================================================================================================| 
                                                                                                                                   
       Date:  04/29/04                           EXPERIMENT: 97006 TEST: 02                                            Page 10      
                     Statistical Analysis of Non-neoplastic Lesions in       Mice(B6C3F1)  -                  METHYL ISOBUTYL KETONE
                                         Terminal Sacrifice at 105 weeks                                                            
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Liver                                                                                                                            | 
|     Clear Cell Focus                                                                                                            | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     22/50 (44%)  13/50 (26%)  13/50 (26%)  20/50 (40%) |3/50 (6%)    4/50 (8%)    5/50 (10%)   2/50 (4%)    | 
|POLY-3 RATE (b)    |     22/46.93     13/47.50     13/42.28     20/46.61    |3/44.99      4/46.15      5/45.87      2/46.84      | 
|POLY-3 PERCENT (g) |     46.9%        27.4%        30.8%        42.9%       |6.7%         8.7%         10.9%        4.3%         | 
|TERMINAL (d)       |     21/40 (53%)  13/42 (31%)  13/35 (37%)  17/37 (46%) |3/35 (9%)    2/37 (5%)    5/39 (13%)   0/38 (0%)    | 
|FIRST INCIDENCE    |     612          729 (T)      729 (T)      551         |731 (T)      687          731 (T)      643          | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     P=0.372      P=0.028N*    P=0.102N     P=0.548N    |P=0.348N     P=0.527      P=0.416      P=0.465N     | 
|POLY 3             |     P=0.503      P=0.037N*    P=0.087N     P=0.429N    |P=0.366N     P=0.514      P=0.367      P=0.482N     | 
|POLY 1.5           |     P=0.515      P=0.041N*    P=0.072N     P=0.428N    |P=0.374N     P=0.508      P=0.363      P=0.488N     | 
|POLY 6             |     P=0.495      P=0.033N*    P=0.100N     P=0.424N    |P=0.353N     P=0.519      P=0.371      P=0.471N     | 
|LOGISTIC REGRESSION|     P=0.445      P=0.027N*    P=0.092N     P=0.469N    |P=0.374N     P=0.512      P=0.416      P=0.493N     | 
|COCH-ARM / FISHERS |     P=0.540      P=0.046N*    P=0.046N*    P=0.420N    |P=0.389N     P=0.500      P=0.357      P=0.500N     | 
|ORDER RESTRICTED   |     P=0.136N     (e)          (e)          (e)         |P=0.332N     (e)          (e)          (e)          | 
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Liver                                                                                                                            | 
|     Eosinophilic Focus                                                                                                          | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     3/50 (6%)    4/50 (8%)    5/50 (10%)   8/50 (16%)  |4/50 (8%)    11/50 (22%)  10/50 (20%)  14/50 (28%)  | 
|POLY-3 RATE (b)    |     3/46.72      4/48.03      5/42.28      8/45.34     |4/45.05      11/45.98     10/46.06     14/46.46     | 
|POLY-3 PERCENT (g) |     6.4%         8.3%         11.8%        17.6%       |8.9%         23.9%        21.7%        30.1%        | 
|TERMINAL (d)       |     2/40 (5%)    3/42 (7%)    5/35 (14%)   8/37 (22%)  |3/35 (9%)    10/37 (27%)  9/39 (23%)   14/38 (37%)  | 
|FIRST INCIDENCE    |     678          565          729 (T)      729 (T)     |715          702          684          731 (T)      | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     P=0.037 *    P=0.524      P=0.289      P=0.080     |P=0.024 *    P=0.059      P=0.107      P=0.014 *    | 
|POLY 3             |     P=0.045 *    P=0.515      P=0.303      P=0.089     |P=0.018 *    P=0.047 *    P=0.078      P=0.009 **   | 
|POLY 1.5           |     P=0.049 *    P=0.508      P=0.318      P=0.093     |P=0.017 *    P=0.046 *    P=0.076      P=0.009 **   | 
|POLY 6             |     P=0.041 *    P=0.524      P=0.290      P=0.085     |P=0.019 *    P=0.047 *    P=0.080      P=0.010 *    | 
|LOGISTIC REGRESSION|     P=0.046 *    P=0.486      P=0.293      P=0.087     |P=0.025 *    P=0.049 *    P=0.082      P=0.015 *    | 
|COCH-ARM / FISHERS |     P=0.056      P=0.500      P=0.357      P=0.100     |P=0.016 *    P=0.045 *    P=0.074      P=0.009 **   | 
|ORDER RESTRICTED   |     P=0.061      (e)          (e)          (e)         |P=0.008 **   (e)          (e)          (e)          | 
|=================================================================================================================================| 
                                                                                                                                   
       Date:  04/29/04                           EXPERIMENT: 97006 TEST: 02                                            Page 11      
                     Statistical Analysis of Non-neoplastic Lesions in       Mice(B6C3F1)  -                  METHYL ISOBUTYL KETONE
                                         Terminal Sacrifice at 105 weeks                                                            
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Liver                                                                                                                            | 
|     Hematopoietic Cell Proliferation                                                                                            | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     0/50 (0%)    0/50 (0%)    0/50 (0%)    0/50 (0%)   |0/50 (0%)    0/50 (0%)    2/50 (4%)    0/50 (0%)    | 
|POLY-3 RATE (b)    |     0/46.53      0/47.50      0/42.28      0/45.34     |0/44.99      0/45.87      2/46.30      0/46.46      | 
|POLY-3 PERCENT (g) |     0.0%         0.0%         0.0%         0.0%        |0.0%         0.0%         4.3%         0.0%         | 
|TERMINAL (d)       |     0/40 (0%)    0/42 (0%)    0/35 (0%)    0/37 (0%)   |0/35 (0%)    0/37 (0%)    0/39 (0%)    0/38 (0%)    | 
|FIRST INCIDENCE    |     ---          ---          ---          ---         |---          ---          648          ---          | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     (e)          (e)          (e)          (e)         |P=0.608      (e)          P=0.247      (e)          | 
|POLY 3             |     (e)          (e)          (e)          (e)         |P=0.609      (e)          P=0.244      (e)          | 
|POLY 1.5           |     (e)          (e)          (e)          (e)         |P=0.605      (e)          P=0.241      (e)          | 
|POLY 6             |     (e)          (e)          (e)          (e)         |P=0.617      (e)          P=0.247      (e)          | 
|LOGISTIC REGRESSION|     (e)          (e)          (e)          (e)         |P=0.589      (e)          P=0.236      (e)          | 
|COCH-ARM / FISHERS |     (e)          (e)          (e)          (e)         |P=0.595      (e)          P=0.247      (e)          | 
|ORDER RESTRICTED   |     (e)          (e)          (e)          (e)         |P=0.253      (e)          (e)          (e)          | 
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Liver                                                                                                                            | 
|     Inflammation Chronic                                                                                                        | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     0/50 (0%)    0/50 (0%)    0/50 (0%)    1/50 (2%)   |0/50 (0%)    1/50 (2%)    0/50 (0%)    2/50 (4%)    | 
|POLY-3 RATE (b)    |     0/46.53      0/47.50      0/42.28      1/45.34     |0/44.99      1/46.23      0/45.87      2/46.46      | 
|POLY-3 PERCENT (g) |     0.0%         0.0%         0.0%         2.2%        |0.0%         2.2%         0.0%         4.3%         | 
|TERMINAL (d)       |     0/40 (0%)    0/42 (0%)    0/35 (0%)    1/37 (3%)   |0/35 (0%)    0/37 (0%)    0/39 (0%)    2/38 (5%)    | 
|FIRST INCIDENCE    |     ---          ---          ---          729 (T)     |---          628          ---          731 (T)      | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     P=0.187      (e)          (e)          P=0.484     |P=0.148      P=0.504      (e)          P=0.257      | 
|POLY 3             |     P=0.194      (e)          (e)          P=0.495     |P=0.144      P=0.505      (e)          P=0.244      | 
|POLY 1.5           |     P=0.196      (e)          (e)          P=0.497     |P=0.143      P=0.503      (e)          P=0.242      | 
|POLY 6             |     P=0.192      (e)          (e)          P=0.493     |P=0.146      P=0.507      (e)          P=0.248      | 
|LOGISTIC REGRESSION|     (e)          (e)          (e)          P=0.484     |P=0.139      P=0.503      (e)          P=0.257      | 
|COCH-ARM / FISHERS |     P=0.198      (e)          (e)          P=0.500     |P=0.140      P=0.500      (e)          P=0.247      | 
|ORDER RESTRICTED   |     P=0.115      (e)          (e)          (e)         |P=0.079      (e)          (e)          (e)          | 
|=================================================================================================================================| 
                                                                                                                                   
       Date:  04/29/04                           EXPERIMENT: 97006 TEST: 02                                            Page 12      
                     Statistical Analysis of Non-neoplastic Lesions in       Mice(B6C3F1)  -                  METHYL ISOBUTYL KETONE
                                         Terminal Sacrifice at 105 weeks                                                            
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Liver                                                                                                                            | 
|     Necrosis                                                                                                                    | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     5/50 (10%)   1/50 (2%)    2/50 (4%)    7/50 (14%)  |3/50 (6%)    1/50 (2%)    5/50 (10%)   1/50 (2%)    | 
|POLY-3 RATE (b)    |     5/46.93      1/48.03      2/43.03      7/46.66     |3/45.20      1/45.93      5/47.68      1/46.46      | 
|POLY-3 PERCENT (g) |     10.7%        2.1%         4.7%         15.0%       |6.6%         2.2%         10.5%        2.2%         | 
|TERMINAL (d)       |     4/40 (10%)   0/42 (0%)    0/35 (0%)    3/37 (8%)   |1/35 (3%)    0/37 (0%)    0/39 (0%)    1/38 (3%)    | 
|FIRST INCIDENCE    |     612          565          519          513         |684          715          551          731 (T)      | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     P=0.130      P=0.101N     P=0.276N     P=0.345     |P=0.350N     P=0.299N     P=0.383      P=0.281N     | 
|POLY 3             |     P=0.135      P=0.096N     P=0.253N     P=0.375     |P=0.358N     P=0.300N     P=0.386      P=0.296N     | 
|POLY 1.5           |     P=0.139      P=0.099N     P=0.243N     P=0.377     |P=0.362N     P=0.302N     P=0.374      P=0.299N     | 
|POLY 6             |     P=0.131      P=0.093N     P=0.260N     P=0.374     |P=0.351N     P=0.299N     P=0.401      P=0.291N     | 
|LOGISTIC REGRESSION|     P=0.166      P=0.111N     P=0.193N     P=0.418     |P=0.386N     P=0.300N     P=0.350      P=0.294N     | 
|COCH-ARM / FISHERS |     P=0.148      P=0.102N     P=0.218N     P=0.380     |P=0.371N     P=0.309N     P=0.357      P=0.309N     | 
|ORDER RESTRICTED   |     P=0.073      (e)          (e)          (e)         |P=0.273N     (e)          (e)          (e)          | 
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Liver                                                                                                                            | 
|     Tension Lipidosis                                                                                                           | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     4/50 (8%)    3/50 (6%)    3/50 (6%)    1/50 (2%)   |1/50 (2%)    2/50 (4%)    3/50 (6%)    0/50 (0%)    | 
|POLY-3 RATE (b)    |     4/46.76      3/47.50      3/44.51      1/45.34     |1/44.99      2/45.87      3/45.87      0/46.46      | 
|POLY-3 PERCENT (g) |     8.6%         6.3%         6.7%         2.2%        |2.2%         4.4%         6.5%         0.0%         | 
|TERMINAL (d)       |     3/40 (8%)    3/42 (7%)    0/35 (0%)    1/37 (3%)   |1/35 (3%)    2/37 (5%)    3/39 (8%)    0/38 (0%)    | 
|FIRST INCIDENCE    |     666          729 (T)      412          729 (T)     |731 (T)      731 (T)      731 (T)      ---          | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     P=0.164N     P=0.474N     P=0.551N     P=0.205N    |P=0.310N     P=0.519      P=0.344      P=0.484N     | 
|POLY 3             |     P=0.148N     P=0.492N     P=0.527N     P=0.188N    |P=0.323N     P=0.507      P=0.312      P=0.494N     | 
|POLY 1.5           |     P=0.144N     P=0.495N     P=0.521N     P=0.185N    |P=0.327N     P=0.504      P=0.310      P=0.496N     | 
|POLY 6             |     P=0.153N     P=0.485N     P=0.531N     P=0.192N    |P=0.315N     P=0.508      P=0.315      P=0.490N     | 
|LOGISTIC REGRESSION|     P=0.105N     P=0.486N     P=0.315N     P=0.187N    |P=0.310N     P=0.519      P=0.344      (e)          | 
|COCH-ARM / FISHERS |     P=0.135N     P=0.500N     P=0.500N     P=0.181N    |P=0.337N     P=0.500      P=0.309      P=0.500N     | 
|ORDER RESTRICTED   |     P=0.155N     (e)          (e)          (e)         |P=0.186N     (e)          (e)          (e)          | 
|=================================================================================================================================| 
                                                                                                                                   
       Date:  04/29/04                           EXPERIMENT: 97006 TEST: 02                                            Page 13      
                     Statistical Analysis of Non-neoplastic Lesions in       Mice(B6C3F1)  -                  METHYL ISOBUTYL KETONE
                                         Terminal Sacrifice at 105 weeks                                                            
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Liver: Hepatocyte                                                                                                                | 
|     Vacuolization Cytoplasmic                                                                                                   | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     1/50 (2%)    0/50 (0%)    2/50 (4%)    1/50 (2%)   |0/50 (0%)    0/50 (0%)    0/50 (0%)    0/50 (0%)    | 
|POLY-3 RATE (b)    |     1/46.73      0/47.50      2/43.52      1/46.12     |0/44.99      0/45.87      0/45.87      0/46.46      | 
|POLY-3 PERCENT (g) |     2.1%         0.0%         4.6%         2.2%        |0.0%         0.0%         0.0%         0.0%         | 
|TERMINAL (d)       |     0/40 (0%)    0/42 (0%)    0/35 (0%)    0/37 (0%)   |0/35 (0%)    0/37 (0%)    0/39 (0%)    0/38 (0%)    | 
|FIRST INCIDENCE    |     676          ---          501          441         |---          ---          ---          ---          | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     P=0.489      P=0.491N     P=0.461      P=0.755     |(e)          (e)          (e)          (e)          | 
|POLY 3             |     P=0.492      P=0.497N     P=0.475      P=0.758     |(e)          (e)          (e)          (e)          | 
|POLY 1.5           |     P=0.496      P=0.498N     P=0.481      P=0.759     |(e)          (e)          (e)          (e)          | 
|POLY 6             |     P=0.487      P=0.494N     P=0.471      P=0.756     |(e)          (e)          (e)          (e)          | 
|LOGISTIC REGRESSION|     P=0.574      P=0.511N     P=0.657      P=0.660N    |(e)          (e)          (e)          (e)          | 
|COCH-ARM / FISHERS |     P=0.500      P=0.500N     P=0.500      P=0.753N    |(e)          (e)          (e)          (e)          | 
|ORDER RESTRICTED   |     P=0.358      (e)          (e)          (e)         |(e)          (e)          (e)          (e)          | 
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Lung: Alveolar Epithelium                                                                                                        | 
|     Hyperplasia                                                                                                                 | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     7/50 (14%)   5/50 (10%)   5/50 (10%)   2/50 (4%)   |1/50 (2%)    5/50 (10%)   3/50 (6%)    5/50 (10%)   | 
|POLY-3 RATE (b)    |     7/46.73      5/47.50      5/42.28      2/45.34     |1/44.99      5/45.87      3/45.87      5/46.49      | 
|POLY-3 PERCENT (g) |     15.0%        10.5%        11.8%        4.4%        |2.2%         10.9%        6.5%         10.8%        | 
|TERMINAL (d)       |     6/40 (15%)   5/42 (12%)   5/35 (14%)   2/37 (5%)   |1/35 (3%)    5/37 (14%)   3/39 (8%)    4/38 (11%)   | 
|FIRST INCIDENCE    |     676          729 (T)      729 (T)      729 (T)     |731 (T)      731 (T)      731 (T)      724          | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     P=0.092N     P=0.346N     P=0.475N     P=0.101N    |P=0.177      P=0.115      P=0.344      P=0.125      | 
|POLY 3             |     P=0.076N     P=0.368N     P=0.451N     P=0.086N    |P=0.163      P=0.106      P=0.312      P=0.109      | 
|POLY 1.5           |     P=0.072N     P=0.373N     P=0.430N     P=0.084N    |P=0.160      P=0.104      P=0.310      P=0.107      | 
|POLY 6             |     P=0.080N     P=0.360N     P=0.468N     P=0.089N    |P=0.170      P=0.106      P=0.315      P=0.113      | 
|LOGISTIC REGRESSION|     P=0.081N     P=0.346N     P=0.463N     P=0.089N    |P=0.184      P=0.115      P=0.344      P=0.125      | 
|COCH-ARM / FISHERS |     P=0.066N     P=0.380N     P=0.380N     P=0.080N    |P=0.151      P=0.102      P=0.309      P=0.102      | 
|ORDER RESTRICTED   |     P=0.071N     (e)          (e)          (e)         |P=0.094      (e)          (e)          (e)          | 
|=================================================================================================================================| 
                                                                                                                                   
       Date:  04/29/04                           EXPERIMENT: 97006 TEST: 02                                            Page 14      
                     Statistical Analysis of Non-neoplastic Lesions in       Mice(B6C3F1)  -                  METHYL ISOBUTYL KETONE
                                         Terminal Sacrifice at 105 weeks                                                            
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Lung: Alveolus                                                                                                                   | 
|     Infiltration Cellular Histiocyte                                                                                            | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     1/50 (2%)    1/50 (2%)    3/50 (6%)    0/50 (0%)   |1/50 (2%)    0/50 (0%)    2/50 (4%)    0/50 (0%)    | 
|POLY-3 RATE (b)    |     1/46.53      1/47.50      3/42.59      0/45.34     |1/45.98      0/45.87      2/46.45      0/46.46      | 
|POLY-3 PERCENT (g) |     2.2%         2.1%         7.0%         0.0%        |2.2%         0.0%         4.3%         0.0%         | 
|TERMINAL (d)       |     1/40 (3%)    1/42 (2%)    1/35 (3%)    0/37 (0%)   |0/35 (0%)    0/37 (0%)    1/39 (3%)    0/38 (0%)    | 
|FIRST INCIDENCE    |     729 (T)      729 (T)      659          ---         |177          ---          551          ---          | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     P=0.443N     P=0.751N     P=0.266      P=0.516N    |P=0.455N     P=0.504N     P=0.513      P=0.500N     | 
|POLY 3             |     P=0.424N     P=0.756N     P=0.274      P=0.505N    |P=0.457N     P=0.500N     P=0.504      P=0.498N     | 
|POLY 1.5           |     P=0.418N     P=0.758N     P=0.282      P=0.503N    |P=0.459N     P=0.501N     P=0.500      P=0.499N     | 
|POLY 6             |     P=0.430N     P=0.753N     P=0.270      P=0.507N    |P=0.452N     P=0.500N     P=0.508      P=0.495N     | 
|LOGISTIC REGRESSION|     P=0.421N     P=0.751N     P=0.277      (e)         |P=0.533N     P=0.341N     P=0.510      (e)          | 
|COCH-ARM / FISHERS |     P=0.409N     P=0.753N     P=0.309      P=0.500N    |P=0.461N     P=0.500N     P=0.500      P=0.500N     | 
|ORDER RESTRICTED   |     P=0.220N     (e)          (e)          (e)         |P=0.323N     (e)          (e)          (e)          | 
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Lung: Bronchiole                                                                                                                 | 
|     Hyperplasia                                                                                                                 | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     1/50 (2%)    2/50 (4%)    3/50 (6%)    2/50 (4%)   |0/50 (0%)    4/50 (8%)    2/50 (4%)    0/50 (0%)    | 
|POLY-3 RATE (b)    |     1/46.53      2/47.50      3/42.28      2/45.34     |0/44.99      4/45.87      2/45.87      0/46.46      | 
|POLY-3 PERCENT (g) |     2.2%         4.2%         7.1%         4.4%        |0.0%         8.7%         4.4%         0.0%         | 
|TERMINAL (d)       |     1/40 (3%)    2/42 (5%)    3/35 (9%)    2/37 (5%)   |0/35 (0%)    4/37 (11%)   2/39 (5%)    0/38 (0%)    | 
|FIRST INCIDENCE    |     729 (T)      729 (T)      729 (T)      729 (T)     |---          731 (T)      731 (T)      ---          | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     P=0.357      P=0.517      P=0.258      P=0.473     |P=0.310N     P=0.070      P=0.262      (e)          | 
|POLY 3             |     P=0.385      P=0.507      P=0.272      P=0.491     |P=0.318N     P=0.063      P=0.242      (e)          | 
|POLY 1.5           |     P=0.393      P=0.504      P=0.281      P=0.494     |P=0.324N     P=0.062      P=0.240      (e)          | 
|POLY 6             |     P=0.378      P=0.513      P=0.265      P=0.488     |P=0.309N     P=0.063      P=0.243      (e)          | 
|LOGISTIC REGRESSION|     P=0.357      P=0.517      P=0.258      P=0.473     |(e)          P=0.070      P=0.262      (e)          | 
|COCH-ARM / FISHERS |     P=0.404      P=0.500      P=0.309      P=0.500     |P=0.337N     P=0.059      P=0.247      (e)          | 
|ORDER RESTRICTED   |     P=0.322      (e)          (e)          (e)         |P=0.181N     (e)          (e)          (e)          | 
|=================================================================================================================================| 
                                                                                                                                   
       Date:  04/29/04                           EXPERIMENT: 97006 TEST: 02                                            Page 15      
                     Statistical Analysis of Non-neoplastic Lesions in       Mice(B6C3F1)  -                  METHYL ISOBUTYL KETONE
                                         Terminal Sacrifice at 105 weeks                                                            
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Lymph Node, Mandibular                                                                                                           | 
|     Hyperplasia Lymphoid                                                                                                        | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     0/37 (0%)    0/36 (0%)    1/32 (3%)    0/34 (0%)   |0/40 (0%)    2/42 (5%)    0/39 (0%)    0/38 (0%)    | 
|POLY-3 RATE (b)    |     0/34.11      0/33.60      1/28.09      0/30.80     |0/35.88      2/38.14      0/35.63      0/35.77      | 
|POLY-3 PERCENT (g) |     0.0%         0.0%         3.6%         0.0%        |0.0%         5.2%         0.0%         0.0%         | 
|TERMINAL (d)       |     0/29 (0%)    0/29 (0%)    1/23 (4%)    0/25 (0%)   |0/29 (0%)    2/31 (7%)    0/30 (0%)    0/31 (0%)    | 
|FIRST INCIDENCE    |     ---          ---          729 (T)      ---         |---          731 (T)      ---          ---          | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     P=0.670      (e)          P=0.454      (e)         |P=0.395N     P=0.253      (e)          (e)          | 
|POLY 3             |     P=0.676      (e)          P=0.461      (e)         |P=0.408N     P=0.250      (e)          (e)          | 
|POLY 1.5           |     P=0.679      (e)          P=0.462      (e)         |P=0.411N     P=0.250      (e)          (e)          | 
|POLY 6             |     P=0.672      (e)          P=0.461      (e)         |P=0.405N     P=0.250      (e)          (e)          | 
|LOGISTIC REGRESSION|     (e)          (e)          P=0.454      (e)         |(e)          P=0.253      (e)          (e)          | 
|COCH-ARM / FISHERS |     P=0.681      (e)          P=0.464      (e)         |P=0.419N     P=0.259      (e)          (e)          | 
|ORDER RESTRICTED   |     P=0.347      (e)          (e)          (e)         |P=0.259N     (e)          (e)          (e)          | 
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Mesentery: Fat                                                                                                                   | 
|     Necrosis                                                                                                                    | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     9/9 (100%)   3/3 (100%)   3/3 (100%)   3/4 (75%)   |9/11 (82%)   9/11 (82%)   11/13 (85%)  7/8 (88%)    | 
|POLY-3 RATE (b)    |     9/9.00       3/3.00       3/3.00       3/3.58      |9/11.00      9/10.02      11/12.88     7/7.83       | 
|POLY-3 PERCENT (g) |     100.0%       100.0%       100.0%       83.9%       |81.8%        89.9%        85.4%        89.4%        | 
|TERMINAL (d)       |     8/8 (100%)   2/2 (100%)   3/3 (100%)   2/2 (100%)  |6/8 (75%)    7/7 (100%)   10/11 (91%)  7/7 (100%)   | 
|FIRST INCIDENCE    |     678          661          729 (T)      656         |537          687          673          731 (T)      | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     P=0.639N     (e)          (e)          P=0.744     |P=0.278N     P=0.530      P=0.568N     P=0.459N     | 
|POLY 3             |     P=0.238N     (e)          (e)          P=0.631N    |P=0.481      P=0.540      P=0.622      P=0.577      | 
|POLY 1.5           |     P=0.176N     (e)          (e)          P=0.458N    |P=0.482      P=0.617      P=0.630      P=0.595      | 
|POLY 6             |     P=0.470N     (e)          (e)          P=0.953N    |P=0.460      P=0.430      P=0.607      P=0.543      | 
|LOGISTIC REGRESSION|     (e)          (e)          (e)          (e)         |P=0.599N     P=0.685      P=0.609      P=0.612      | 
|COCH-ARM / FISHERS |     P=0.133N     (e)          (e)          P=0.308N    |P=0.472      P=0.707N     P=0.637      P=0.624      | 
|ORDER RESTRICTED   |     P=0.044N*    (e)          (e)          (e)         |P=0.517      (e)          (e)          (e)          | 
|=================================================================================================================================| 
                                                                                                                                   
       Date:  04/29/04                           EXPERIMENT: 97006 TEST: 02                                            Page 16      
                     Statistical Analysis of Non-neoplastic Lesions in       Mice(B6C3F1)  -                  METHYL ISOBUTYL KETONE
                                         Terminal Sacrifice at 105 weeks                                                            
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Nose                                                                                                                             | 
|     Inflammation                                                                                                                | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     4/50 (8%)    1/50 (2%)    3/50 (6%)    2/50 (4%)   |4/50 (8%)    3/50 (6%)    2/50 (4%)    0/49 (0%)    | 
|POLY-3 RATE (b)    |     4/46.72      1/47.50      3/42.92      2/46.12     |4/46.08      3/47.23      2/45.99      0/45.46      | 
|POLY-3 PERCENT (g) |     8.6%         2.1%         7.0%         4.3%        |8.7%         6.4%         4.4%         0.0%         | 
|TERMINAL (d)       |     3/40 (8%)    1/42 (2%)    2/35 (6%)    1/37 (3%)   |2/35 (6%)    1/37 (3%)    1/39 (3%)    0/37 (0%)    | 
|FIRST INCIDENCE    |     678          729 (T)      520          441         |177          21           701          ---          | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     P=0.413N     P=0.166N     P=0.567N     P=0.365N    |P=0.035N*    P=0.485N     P=0.316N     P=0.060N     | 
|POLY 3             |     P=0.385N     P=0.174N     P=0.546N     P=0.343N    |P=0.038N*    P=0.486N     P=0.338N     P=0.062N     | 
|POLY 1.5           |     P=0.380N     P=0.176N     P=0.534N     P=0.341N    |P=0.039N*    P=0.491N     P=0.341N     P=0.063N     | 
|POLY 6             |     P=0.392N     P=0.170N     P=0.555N     P=0.347N    |P=0.037N*    P=0.483N     P=0.335N     P=0.060N     | 
|LOGISTIC REGRESSION|     P=0.347N     P=0.172N     P=0.505N     P=0.291N    |P=0.045N*    P=0.536N     P=0.338N     P=0.081N     | 
|COCH-ARM / FISHERS |     P=0.371N     P=0.181N     P=0.500N     P=0.339N    |P=0.038N*    P=0.500N     P=0.339N     P=0.061N     | 
|ORDER RESTRICTED   |     P=0.293N     (e)          (e)          (e)         |P=0.037N*    (e)          (e)          (e)          | 
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Nose: Glands                                                                                                                     | 
|     Hyperplasia                                                                                                                 | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     33/50 (66%)  32/50 (64%)  24/50 (48%)  26/50 (52%) |23/50 (46%)  30/50 (60%)  23/50 (46%)  20/49 (41%)  | 
|POLY-3 RATE (b)    |     33/48.30     32/49.14     24/45.48     26/47.29    |23/47.28     30/47.75     23/46.66     20/45.96     | 
|POLY-3 PERCENT (g) |     68.3%        65.1%        52.8%        55.0%       |48.7%        62.8%        49.3%        43.5%        | 
|TERMINAL (d)       |     27/40 (68%)  27/42 (64%)  18/35 (51%)  20/37 (54%) |15/35 (43%)  23/37 (62%)  19/39 (49%)  18/37 (49%)  | 
|FIRST INCIDENCE    |     598          493          412          551         |368          515          648          617          | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     P=0.198N     P=0.390N     P=0.217N     P=0.240N    |P=0.111N     P=0.203      P=0.433N     P=0.271N     | 
|POLY 3             |     P=0.076N     P=0.452N     P=0.087N     P=0.125N    |P=0.177N     P=0.115      P=0.557      P=0.386N     | 
|POLY 1.5           |     P=0.068N     P=0.471N     P=0.077N     P=0.119N    |P=0.170N     P=0.112      P=0.563      P=0.379N     | 
|POLY 6             |     P=0.084N     P=0.431N     P=0.098N     P=0.132N    |P=0.181N     P=0.115      P=0.547      P=0.390N     | 
|LOGISTIC REGRESSION|     P=0.071N     P=0.485N     P=0.085N     P=0.129N    |P=0.147N     P=0.119      P=0.564N     P=0.351N     | 
|COCH-ARM / FISHERS |     P=0.058N     P=0.500N     P=0.053N     P=0.111N    |P=0.170N     P=0.115      P=0.579N     P=0.376N     | 
|ORDER RESTRICTED   |     P=0.108N     (e)          (e)          (e)         |P=0.180N     (e)          (e)          (e)          | 
|=================================================================================================================================| 
                                                                                                                                   
       Date:  04/29/04                           EXPERIMENT: 97006 TEST: 02                                            Page 17      
                     Statistical Analysis of Non-neoplastic Lesions in       Mice(B6C3F1)  -                  METHYL ISOBUTYL KETONE
                                         Terminal Sacrifice at 105 weeks                                                            
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Nose: Olfactory Epithelium                                                                                                       | 
|     Degeneration Hyaline                                                                                                        | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     1/50 (2%)    1/50 (2%)    2/50 (4%)    0/50 (0%)   |8/50 (16%)   5/50 (10%)   4/50 (8%)    1/49 (2%)    | 
|POLY-3 RATE (b)    |     1/46.73      1/47.50      2/43.28      0/45.34     |8/46.13      5/45.87      4/46.49      1/45.46      | 
|POLY-3 PERCENT (g) |     2.1%         2.1%         4.6%         0.0%        |17.3%        10.9%        8.6%         2.2%         | 
|TERMINAL (d)       |     0/40 (0%)    1/42 (2%)    1/35 (3%)    0/37 (0%)   |6/35 (17%)   5/37 (14%)   3/39 (8%)    1/37 (3%)    | 
|FIRST INCIDENCE    |     676          729 (T)      26           ---         |177          731 (T)      530          731 (T)      | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     P=0.389N     P=0.750N     P=0.470      P=0.510N    |P=0.010N*    P=0.249N     P=0.146N     P=0.016N*    | 
|POLY 3             |     P=0.380N     P=0.757N     P=0.473      P=0.506N    |P=0.012N*    P=0.279N     P=0.173N     P=0.017N*    | 
|POLY 1.5           |     P=0.375N     P=0.758N     P=0.483      P=0.504N    |P=0.012N*    P=0.282N     P=0.178N     P=0.017N*    | 
|POLY 6             |     P=0.387N     P=0.754N     P=0.466      P=0.509N    |P=0.011N*    P=0.278N     P=0.168N     P=0.016N*    | 
|LOGISTIC REGRESSION|     P=0.282N     P=0.759      P=0.731N     P=0.483N    |P=0.013N*    P=0.278N     P=0.181N     P=0.022N*    | 
|COCH-ARM / FISHERS |     P=0.366N     P=0.753N     P=0.500      P=0.500N    |P=0.013N*    P=0.277N     P=0.178N     P=0.017N*    | 
|ORDER RESTRICTED   |     P=0.271N     (e)          (e)          (e)         |P=0.009N**   (e)          (e)          (e)          | 
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Nose: Respiratory Epithelium                                                                                                     | 
|     Degeneration Hyaline                                                                                                        | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     0/50 (0%)    1/50 (2%)    3/50 (6%)    0/50 (0%)   |24/50 (48%)  19/50 (38%)  20/50 (40%)  13/49 (27%)  | 
|POLY-3 RATE (b)    |     0/46.53      1/47.50      3/42.28      0/45.34     |24/46.43     19/47.21     20/47.65     13/45.66     | 
|POLY-3 PERCENT (g) |     0.0%         2.1%         7.1%         0.0%        |51.7%        40.3%        42.0%        28.5%        | 
|TERMINAL (d)       |     0/40 (0%)    1/42 (2%)    3/35 (9%)    0/37 (0%)   |20/35 (57%)  13/37 (35%)  15/39 (39%)  11/37 (30%)  | 
|FIRST INCIDENCE    |     ---          729 (T)      729 (T)      ---         |177          598          75           687          | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     P=0.602      P=0.510      P=0.098      (e)         |P=0.015N*    P=0.170N     P=0.173N     P=0.012N*    | 
|POLY 3             |     P=0.621      P=0.504      P=0.102      (e)         |P=0.020N*    P=0.181N     P=0.228N     P=0.017N*    | 
|POLY 1.5           |     P=0.627      P=0.502      P=0.107      (e)         |P=0.021N*    P=0.200N     P=0.245N     P=0.019N*    | 
|POLY 6             |     P=0.615      P=0.507      P=0.099      (e)         |P=0.017N*    P=0.159N     P=0.208N     P=0.014N*    | 
|LOGISTIC REGRESSION|     (e)          P=0.510      P=0.098      (e)         |P=0.022N*    P=0.202N     P=0.273N     P=0.019N*    | 
|COCH-ARM / FISHERS |     P=0.634      P=0.500      P=0.121      (e)         |P=0.023N*    P=0.210N     P=0.273N     P=0.022N*    | 
|ORDER RESTRICTED   |     P=0.202      (e)          (e)          (e)         |P=0.014N*    (e)          (e)          (e)          | 
|=================================================================================================================================| 
                                                                                                                                   
       Date:  04/29/04                           EXPERIMENT: 97006 TEST: 02                                            Page 18      
                     Statistical Analysis of Non-neoplastic Lesions in       Mice(B6C3F1)  -                  METHYL ISOBUTYL KETONE
                                         Terminal Sacrifice at 105 weeks                                                            
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Nose: Respiratory Epithelium                                                                                                     | 
|     Metaplasia                                                                                                                  | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     9/50 (18%)   11/50 (22%)  13/50 (26%)  6/50 (12%)  |3/50 (6%)    3/50 (6%)    7/50 (14%)   1/49 (2%)    | 
|POLY-3 RATE (b)    |     9/46.53      11/48.19     13/42.87     6/46.11     |3/45.28      3/46.85      7/46.13      1/45.46      | 
|POLY-3 PERCENT (g) |     19.3%        22.8%        30.3%        13.0%       |6.6%         6.4%         15.2%        2.2%         | 
|TERMINAL (d)       |     9/40 (23%)   10/42 (24%)  11/35 (31%)  4/37 (11%)  |1/35 (3%)    1/37 (3%)    5/39 (13%)   1/37 (3%)    | 
|FIRST INCIDENCE    |     729 (T)      493          639          551         |681          515          695          731 (T)      | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     P=0.316N     P=0.447      P=0.139      P=0.341N    |P=0.295N     P=0.645N     P=0.197      P=0.286N     | 
|POLY 3             |     P=0.245N     P=0.435      P=0.168      P=0.293N    |P=0.318N     P=0.646N     P=0.165      P=0.304N     | 
|POLY 1.5           |     P=0.238N     P=0.421      P=0.184      P=0.292N    |P=0.320N     P=0.652N     P=0.162      P=0.306N     | 
|POLY 6             |     P=0.248N     P=0.455      P=0.160      P=0.292N    |P=0.312N     P=0.642N     P=0.167      P=0.300N     | 
|LOGISTIC REGRESSION|     P=0.255N     P=0.417      P=0.145      P=0.303N    |P=0.330N     P=0.662      P=0.165      P=0.305N     | 
|COCH-ARM / FISHERS |     P=0.225N     P=0.402      P=0.235      P=0.288N    |P=0.330N     P=0.661N     P=0.159      P=0.316N     | 
|ORDER RESTRICTED   |     P=0.148N     (e)          (e)          (e)         |P=0.151N     (e)          (e)          (e)          | 
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Nose: Turbinate                                                                                                                  | 
|     Necrosis                                                                                                                    | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     0/50 (0%)    0/50 (0%)    0/50 (0%)    0/50 (0%)   |0/50 (0%)    0/50 (0%)    2/50 (4%)    0/49 (0%)    | 
|POLY-3 RATE (b)    |     0/46.53      0/47.50      0/42.28      0/45.34     |0/44.99      0/45.87      2/45.87      0/45.46      | 
|POLY-3 PERCENT (g) |     0.0%         0.0%         0.0%         0.0%        |0.0%         0.0%         4.4%         0.0%         | 
|TERMINAL (d)       |     0/40 (0%)    0/42 (0%)    0/35 (0%)    0/37 (0%)   |0/35 (0%)    0/37 (0%)    2/39 (5%)    0/37 (0%)    | 
|FIRST INCIDENCE    |     ---          ---          ---          ---         |---          ---          731 (T)      ---          | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     (e)          (e)          (e)          (e)         |P=0.606      (e)          P=0.262      (e)          | 
|POLY 3             |     (e)          (e)          (e)          (e)         |P=0.605      (e)          P=0.242      (e)          | 
|POLY 1.5           |     (e)          (e)          (e)          (e)         |P=0.601      (e)          P=0.240      (e)          | 
|POLY 6             |     (e)          (e)          (e)          (e)         |P=0.613      (e)          P=0.243      (e)          | 
|LOGISTIC REGRESSION|     (e)          (e)          (e)          (e)         |(e)          (e)          P=0.262      (e)          | 
|COCH-ARM / FISHERS |     (e)          (e)          (e)          (e)         |P=0.591      (e)          P=0.247      (e)          | 
|ORDER RESTRICTED   |     (e)          (e)          (e)          (e)         |P=0.251      (e)          (e)          (e)          | 
|=================================================================================================================================| 
                                                                                                                                   
       Date:  04/29/04                           EXPERIMENT: 97006 TEST: 02                                            Page 19      
                     Statistical Analysis of Non-neoplastic Lesions in       Mice(B6C3F1)  -                  METHYL ISOBUTYL KETONE
                                         Terminal Sacrifice at 105 weeks                                                            
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Ovary                                                                                                                            | 
|     Cyst                                                                                                                        | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |                                                        |14/49 (29%)  13/50 (26%)  13/48 (27%)  9/50 (18%)   | 
|POLY-3 RATE (b)    |                                                        |14/44.98     13/46.62     13/45.13     9/46.62      | 
|POLY-3 PERCENT (g) |                                                        |31.1%        27.9%        28.8%        19.3%        | 
|TERMINAL (d)       |                                                        |14/35 (40%)  7/37 (19%)   10/38 (26%)  7/38 (18%)   | 
|FIRST INCIDENCE    |                                                        |731 (T)      662          530          705          | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |                                                        |P=0.102N     P=0.441N     P=0.407N     P=0.115N     | 
|POLY 3             |                                                        |P=0.121N     P=0.456N     P=0.496N     P=0.143N     | 
|POLY 1.5           |                                                        |P=0.127N     P=0.473N     P=0.516N     P=0.151N     | 
|POLY 6             |                                                        |P=0.110N     P=0.433N     P=0.467N     P=0.129N     | 
|LOGISTIC REGRESSION|                                                        |P=0.121N     P=0.471N     P=0.523N     P=0.108N     | 
|COCH-ARM / FISHERS |                                                        |P=0.132N     P=0.475N     P=0.525N     P=0.157N     | 
|ORDER RESTRICTED   |                                                        |P=0.155N     (e)          (e)          (e)          | 
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Pancreas                                                                                                                         | 
|     Atrophy                                                                                                                     | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     0/49 (0%)    0/50 (0%)    0/49 (0%)    0/50 (0%)   |3/50 (6%)    0/50 (0%)    1/49 (2%)    0/50 (0%)    | 
|POLY-3 RATE (b)    |     0/46.24      0/47.50      0/41.84      0/45.34     |3/45.09      0/45.87      1/45.09      0/46.46      | 
|POLY-3 PERCENT (g) |     0.0%         0.0%         0.0%         0.0%        |6.7%         0.0%         2.2%         0.0%         | 
|TERMINAL (d)       |     0/40 (0%)    0/42 (0%)    0/35 (0%)    0/37 (0%)   |2/35 (6%)    0/37 (0%)    1/39 (3%)    0/38 (0%)    | 
|FIRST INCIDENCE    |     ---          ---          ---          ---         |706          ---          731 (T)      ---          | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     (e)          (e)          (e)          (e)         |P=0.078N     P=0.115N     P=0.278N     P=0.108N     | 
|POLY 3             |     (e)          (e)          (e)          (e)         |P=0.085N     P=0.116N     P=0.305N     P=0.113N     | 
|POLY 1.5           |     (e)          (e)          (e)          (e)         |P=0.085N     P=0.117N     P=0.308N     P=0.115N     | 
|POLY 6             |     (e)          (e)          (e)          (e)         |P=0.084N     P=0.115N     P=0.302N     P=0.111N     | 
|LOGISTIC REGRESSION|     (e)          (e)          (e)          (e)         |P=0.081N     P=0.116N     P=0.298N     P=0.112N     | 
|COCH-ARM / FISHERS |     (e)          (e)          (e)          (e)         |P=0.087N     P=0.121N     P=0.316N     P=0.121N     | 
|ORDER RESTRICTED   |     (e)          (e)          (e)          (e)         |P=0.019N*    (e)          (e)          (e)          | 
|=================================================================================================================================| 
                                                                                                                                   
       Date:  04/29/04                           EXPERIMENT: 97006 TEST: 02                                            Page 20      
                     Statistical Analysis of Non-neoplastic Lesions in       Mice(B6C3F1)  -                  METHYL ISOBUTYL KETONE
                                         Terminal Sacrifice at 105 weeks                                                            
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Pituitary Gland: Pars Distalis                                                                                                   | 
|     Angiectasis                                                                                                                 | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     0/50 (0%)    0/47 (0%)    0/48 (0%)    0/49 (0%)   |1/50 (2%)    3/49 (6%)    3/48 (6%)    2/49 (4%)    | 
|POLY-3 RATE (b)    |     0/46.53      0/45.01      0/40.84      0/44.34     |1/44.99      3/45.32      3/44.28      2/45.56      | 
|POLY-3 PERCENT (g) |     0.0%         0.0%         0.0%         0.0%        |2.2%         6.6%         6.8%         4.4%         | 
|TERMINAL (d)       |     0/40 (0%)    0/42 (0%)    0/34 (0%)    0/36 (0%)   |1/35 (3%)    1/36 (3%)    3/39 (8%)    1/38 (3%)    | 
|FIRST INCIDENCE    |     ---          ---          ---          ---         |731 (T)      628          731 (T)      714          | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     (e)          (e)          (e)          (e)         |P=0.516      P=0.319      P=0.344      P=0.533      | 
|POLY 3             |     (e)          (e)          (e)          (e)         |P=0.487      P=0.308      P=0.299      P=0.504      | 
|POLY 1.5           |     (e)          (e)          (e)          (e)         |P=0.481      P=0.304      P=0.296      P=0.501      | 
|POLY 6             |     (e)          (e)          (e)          (e)         |P=0.498      P=0.311      P=0.304      P=0.511      | 
|LOGISTIC REGRESSION|     (e)          (e)          (e)          (e)         |P=0.479      P=0.298      P=0.344      P=0.513      | 
|COCH-ARM / FISHERS |     (e)          (e)          (e)          (e)         |P=0.469      P=0.301      P=0.293      P=0.492      | 
|ORDER RESTRICTED   |     (e)          (e)          (e)          (e)         |P=0.333      (e)          (e)          (e)          | 
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Pituitary Gland: Pars Distalis                                                                                                   | 
|     Hyperplasia                                                                                                                 | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     1/50 (2%)    0/47 (0%)    2/48 (4%)    0/49 (0%)   |10/50 (20%)  8/49 (16%)   13/48 (27%)  11/49 (22%)  | 
|POLY-3 RATE (b)    |     1/46.53      0/45.01      2/41.57      0/44.34     |10/45.02     8/44.87      13/44.81     11/45.49     | 
|POLY-3 PERCENT (g) |     2.2%         0.0%         4.8%         0.0%        |22.2%        17.8%        29.0%        24.2%        | 
|TERMINAL (d)       |     1/40 (3%)    0/42 (0%)    1/34 (3%)    0/36 (0%)   |9/35 (26%)   8/36 (22%)   12/39 (31%)  11/38 (29%)  | 
|FIRST INCIDENCE    |     729 (T)      ---          471          ---         |724          731 (T)      567          731 (T)      | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     P=0.488N     P=0.490N     P=0.458      P=0.521N    |P=0.425      P=0.369N     P=0.421      P=0.586      | 
|POLY 3             |     P=0.476N     P=0.507N     P=0.461      P=0.510N    |P=0.351      P=0.399N     P=0.310      P=0.511      | 
|POLY 1.5           |     P=0.470N     P=0.509N     P=0.467      P=0.507N    |P=0.342      P=0.406N     P=0.296      P=0.501      | 
|POLY 6             |     P=0.483N     P=0.502N     P=0.457      P=0.512N    |P=0.369      P=0.397N     P=0.327      P=0.528      | 
|LOGISTIC REGRESSION|     P=0.436N     (e)          P=0.550      (e)         |P=0.390      P=0.380N     P=0.310      P=0.591      | 
|COCH-ARM / FISHERS |     P=0.462N     P=0.515N     P=0.485      P=0.505N    |P=0.322      P=0.416N     P=0.278      P=0.479      | 
|ORDER RESTRICTED   |     P=0.316N     (e)          (e)          (e)         |P=0.365      (e)          (e)          (e)          | 
|=================================================================================================================================| 
                                                                                                                                   
       Date:  04/29/04                           EXPERIMENT: 97006 TEST: 02                                            Page 21      
                     Statistical Analysis of Non-neoplastic Lesions in       Mice(B6C3F1)  -                  METHYL ISOBUTYL KETONE
                                         Terminal Sacrifice at 105 weeks                                                            
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Preputial Gland                                                                                                                  | 
|     Ectasia                                                                                                                     | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     2/50 (4%)    3/50 (6%)    0/50 (0%)    1/50 (2%)   |                                                    | 
|POLY-3 RATE (b)    |     2/46.73      3/47.60      0/42.28      1/45.34     |                                                    | 
|POLY-3 PERCENT (g) |     4.3%         6.3%         0.0%         2.2%        |                                                    | 
|TERMINAL (d)       |     1/40 (3%)    2/42 (5%)    0/35 (0%)    1/37 (3%)   |                                                    | 
|FIRST INCIDENCE    |     676          704          ---          729 (T)     |                                                    | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     P=0.273N     P=0.524      P=0.268N     P=0.524N    |                                                    | 
|POLY 3             |     P=0.256N     P=0.508      P=0.260N     P=0.510N    |                                                    | 
|POLY 1.5           |     P=0.251N     P=0.504      P=0.253N     P=0.506N    |                                                    | 
|POLY 6             |     P=0.261N     P=0.515      P=0.266N     P=0.515N    |                                                    | 
|LOGISTIC REGRESSION|     P=0.256N     P=0.502      P=0.247N     P=0.506N    |                                                    | 
|COCH-ARM / FISHERS |     P=0.242N     P=0.500      P=0.247N     P=0.500N    |                                                    | 
|ORDER RESTRICTED   |     P=0.205N     (e)          (e)          (e)         |                                                    | 
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Preputial Gland                                                                                                                  | 
|     Inflammation Chronic                                                                                                        | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     0/50 (0%)    1/50 (2%)    0/50 (0%)    2/50 (4%)   |                                                    | 
|POLY-3 RATE (b)    |     0/46.53      1/47.50      0/42.28      2/45.81     |                                                    | 
|POLY-3 PERCENT (g) |     0.0%         2.1%         0.0%         4.4%        |                                                    | 
|TERMINAL (d)       |     0/40 (0%)    1/42 (2%)    0/35 (0%)    1/37 (3%)   |                                                    | 
|FIRST INCIDENCE    |     ---          729 (T)      ---          593         |                                                    | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     P=0.129      P=0.510      (e)          P=0.227     |                                                    | 
|POLY 3             |     P=0.135      P=0.504      (e)          P=0.234     |                                                    | 
|POLY 1.5           |     P=0.136      P=0.502      (e)          P=0.235     |                                                    | 
|POLY 6             |     P=0.134      P=0.507      (e)          P=0.233     |                                                    | 
|LOGISTIC REGRESSION|     P=0.142      P=0.510      (e)          P=0.264     |                                                    | 
|COCH-ARM / FISHERS |     P=0.140      P=0.500      (e)          P=0.247     |                                                    | 
|ORDER RESTRICTED   |     P=0.073      (e)          (e)          (e)         |                                                    | 
|=================================================================================================================================| 
                                                                                                                                   
       Date:  04/29/04                           EXPERIMENT: 97006 TEST: 02                                            Page 22      
                     Statistical Analysis of Non-neoplastic Lesions in       Mice(B6C3F1)  -                  METHYL ISOBUTYL KETONE
                                         Terminal Sacrifice at 105 weeks                                                            
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Skin                                                                                                                             | 
|     Inflammation Chronic                                                                                                        | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     0/50 (0%)    2/50 (4%)    1/49 (2%)    0/50 (0%)   |2/50 (4%)    2/50 (4%)    5/50 (10%)   2/50 (4%)    | 
|POLY-3 RATE (b)    |     0/46.53      2/47.52      1/41.99      0/45.34     |2/44.99      2/45.87      5/46.49      2/46.46      | 
|POLY-3 PERCENT (g) |     0.0%         4.2%         2.4%         0.0%        |4.5%         4.4%         10.8%        4.3%         | 
|TERMINAL (d)       |     0/40 (0%)    1/42 (2%)    0/34 (0%)    0/37 (0%)   |2/35 (6%)    2/37 (5%)    4/39 (10%)   2/38 (5%)    | 
|FIRST INCIDENCE    |     ---          724          480          ---         |731 (T)      731 (T)      530          731 (T)      | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     P=0.481N     P=0.253      P=0.488      (e)         |P=0.556      P=0.675N     P=0.258      P=0.665N     | 
|POLY 3             |     P=0.472N     P=0.242      P=0.480      (e)         |P=0.540      P=0.687N     P=0.230      P=0.682N     | 
|POLY 1.5           |     P=0.469N     P=0.240      P=0.484      (e)         |P=0.534      P=0.690N     P=0.225      P=0.686N     | 
|POLY 6             |     P=0.475N     P=0.245      P=0.477      (e)         |P=0.552      P=0.686N     P=0.235      P=0.676N     | 
|LOGISTIC REGRESSION|     P=0.436N     P=0.250      P=0.669      (e)         |P=0.530      P=0.675N     P=0.218      P=0.665N     | 
|COCH-ARM / FISHERS |     P=0.462N     P=0.247      P=0.495      (e)         |P=0.521      P=0.691N     P=0.218      P=0.691N     | 
|ORDER RESTRICTED   |     P=0.317      (e)          (e)          (e)         |P=0.420      (e)          (e)          (e)          | 
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Spleen                                                                                                                           | 
|     Hematopoietic Cell Proliferation                                                                                            | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     2/50 (4%)    1/50 (2%)    1/49 (2%)    3/49 (6%)   |5/50 (10%)   1/50 (2%)    7/49 (14%)   5/50 (10%)   | 
|POLY-3 RATE (b)    |     2/46.53      1/47.50      1/41.84      3/45.58     |5/45.24      1/46.20      7/46.27      5/46.46      | 
|POLY-3 PERCENT (g) |     4.3%         2.1%         2.4%         6.6%        |11.1%        2.2%         15.1%        10.8%        | 
|TERMINAL (d)       |     2/40 (5%)    1/42 (2%)    1/35 (3%)    1/37 (3%)   |3/35 (9%)    0/37 (0%)    3/39 (8%)    5/38 (13%)   | 
|FIRST INCIDENCE    |     729 (T)      729 (T)      729 (T)      513         |691          638          551          731 (T)      | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     P=0.293      P=0.483N     P=0.547N     P=0.474     |P=0.384      P=0.101N     P=0.429      P=0.577N     | 
|POLY 3             |     P=0.309      P=0.493N     P=0.537N     P=0.491     |P=0.348      P=0.097N     P=0.395      P=0.613N     | 
|POLY 1.5           |     P=0.312      P=0.496N     P=0.529N     P=0.490     |P=0.346      P=0.099N     P=0.382      P=0.618N     | 
|POLY 6             |     P=0.307      P=0.487N     P=0.542N     P=0.492     |P=0.355      P=0.095N     P=0.410      P=0.607N     | 
|LOGISTIC REGRESSION|     P=0.317      P=0.483N     P=0.547N     P=0.511     |P=0.339      P=0.102N     P=0.365      P=0.598N     | 
|COCH-ARM / FISHERS |     P=0.316      P=0.500N     P=0.508N     P=0.490     |P=0.337      P=0.102N     P=0.365      P=0.630N     | 
|ORDER RESTRICTED   |     P=0.288      (e)          (e)          (e)         |P=0.240      (e)          (e)          (e)          | 
|=================================================================================================================================| 
                                                                                                                                   
       Date:  04/29/04                           EXPERIMENT: 97006 TEST: 02                                            Page 23      
                     Statistical Analysis of Non-neoplastic Lesions in       Mice(B6C3F1)  -                  METHYL ISOBUTYL KETONE
                                         Terminal Sacrifice at 105 weeks                                                            
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Stomach, Forestomach                                                                                                             | 
|     Hyperplasia                                                                                                                 | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     3/50 (6%)    3/49 (6%)    2/49 (4%)    1/50 (2%)   |1/50 (2%)    2/50 (4%)    1/50 (2%)    2/50 (4%)    | 
|POLY-3 RATE (b)    |     3/47.53      3/46.69      2/42.99      1/45.68     |1/45.50      2/46.05      1/45.87      2/46.46      | 
|POLY-3 PERCENT (g) |     6.3%         6.4%         4.7%         2.2%        |2.2%         4.3%         2.2%         4.3%         | 
|TERMINAL (d)       |     0/40 (0%)    3/42 (7%)    0/35 (0%)    0/37 (0%)   |0/35 (0%)    1/37 (3%)    1/39 (3%)    2/38 (5%)    | 
|FIRST INCIDENCE    |     612          729 (T)      480          637         |578          683          731 (T)      731 (T)      | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     P=0.227N     P=0.645N     P=0.559N     P=0.329N    |P=0.467      P=0.512      P=0.751N     P=0.519      | 
|POLY 3             |     P=0.210N     P=0.654      P=0.545N     P=0.320N    |P=0.452      P=0.504      P=0.759N     P=0.507      | 
|POLY 1.5           |     P=0.204N     P=0.653      P=0.536N     P=0.314N    |P=0.451      P=0.503      P=0.759N     P=0.505      | 
|POLY 6             |     P=0.217N     P=0.655      P=0.553N     P=0.326N    |P=0.457      P=0.505      P=0.759N     P=0.511      | 
|LOGISTIC REGRESSION|     P=0.157N     P=0.631      P=0.344N     P=0.220N    |P=0.443      P=0.500      P=0.762      P=0.489      | 
|COCH-ARM / FISHERS |     P=0.193N     P=0.651      P=0.510N     P=0.309N    |P=0.444      P=0.500      P=0.753N     P=0.500      | 
|ORDER RESTRICTED   |     P=0.277N     (e)          (e)          (e)         |P=0.452      (e)          (e)          (e)          | 
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Stomach, Forestomach                                                                                                             | 
|     Inflammation                                                                                                                | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     1/50 (2%)    2/49 (4%)    3/49 (6%)    0/50 (0%)   |0/50 (0%)    1/50 (2%)    0/50 (0%)    2/50 (4%)    | 
|POLY-3 RATE (b)    |     1/46.90      2/46.69      3/43.63      0/45.34     |0/44.99      1/46.05      0/45.87      2/46.46      | 
|POLY-3 PERCENT (g) |     2.1%         4.3%         6.9%         0.0%        |0.0%         2.2%         0.0%         4.3%         | 
|TERMINAL (d)       |     0/40 (0%)    2/42 (5%)    0/35 (0%)    0/37 (0%)   |0/35 (0%)    0/37 (0%)    0/39 (0%)    2/38 (5%)    | 
|FIRST INCIDENCE    |     622          729 (T)      480          ---         |---          683          ---          731 (T)      | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     P=0.364N     P=0.516      P=0.270      P=0.509N    |P=0.151      P=0.505      (e)          P=0.257      | 
|POLY 3             |     P=0.355N     P=0.498      P=0.280      P=0.507N    |P=0.144      P=0.505      (e)          P=0.244      | 
|POLY 1.5           |     P=0.347N     P=0.496      P=0.283      P=0.504N    |P=0.143      P=0.503      (e)          P=0.242      | 
|POLY 6             |     P=0.363N     P=0.503      P=0.279      P=0.510N    |P=0.147      P=0.506      (e)          P=0.248      | 
|LOGISTIC REGRESSION|     P=0.280N     P=0.480      P=0.485      P=0.443N    |P=0.143      P=0.499      (e)          P=0.257      | 
|COCH-ARM / FISHERS |     P=0.336N     P=0.492      P=0.301      P=0.500N    |P=0.140      P=0.500      (e)          P=0.247      | 
|ORDER RESTRICTED   |     P=0.184N     (e)          (e)          (e)         |P=0.079      (e)          (e)          (e)          | 
|=================================================================================================================================| 
                                                                                                                                   
       Date:  04/29/04                           EXPERIMENT: 97006 TEST: 02                                            Page 24      
                     Statistical Analysis of Non-neoplastic Lesions in       Mice(B6C3F1)  -                  METHYL ISOBUTYL KETONE
                                         Terminal Sacrifice at 105 weeks                                                            
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Stomach, Forestomach                                                                                                             | 
|     Ulcer                                                                                                                       | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     2/50 (4%)    1/49 (2%)    0/49 (0%)    2/50 (4%)   |0/50 (0%)    0/50 (0%)    0/50 (0%)    0/50 (0%)    | 
|POLY-3 RATE (b)    |     2/46.73      1/47.18      0/41.84      2/46.69     |0/44.99      0/45.87      0/45.87      0/46.46      | 
|POLY-3 PERCENT (g) |     4.3%         2.1%         0.0%         4.3%        |0.0%         0.0%         0.0%         0.0%         | 
|TERMINAL (d)       |     1/40 (3%)    0/42 (0%)    0/35 (0%)    0/37 (0%)   |0/35 (0%)    0/37 (0%)    0/39 (0%)    0/38 (0%)    | 
|FIRST INCIDENCE    |     676          582          ---          441         |---          ---          ---          ---          | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     P=0.570      P=0.492N     P=0.268N     P=0.679     |(e)          (e)          (e)          (e)          | 
|POLY 3             |     P=0.582      P=0.497N     P=0.263N     P=0.693     |(e)          (e)          (e)          (e)          | 
|POLY 1.5           |     P=0.586      P=0.501N     P=0.257N     P=0.694     |(e)          (e)          (e)          (e)          | 
|POLY 6             |     P=0.578      P=0.490N     P=0.267N     P=0.693     |(e)          (e)          (e)          (e)          | 
|LOGISTIC REGRESSION|     P=0.604N     P=0.532N     P=0.250N     P=0.573N    |(e)          (e)          (e)          (e)          | 
|COCH-ARM / FISHERS |     P=0.592      P=0.508N     P=0.253N     P=0.691N    |(e)          (e)          (e)          (e)          | 
|ORDER RESTRICTED   |     P=0.425      (e)          (e)          (e)         |(e)          (e)          (e)          (e)          | 
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Stomach, Forestomach: Artery                                                                                                     | 
|     Inflammation Chronic                                                                                                        | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     0/50 (0%)    0/49 (0%)    0/49 (0%)    0/50 (0%)   |2/50 (4%)    0/50 (0%)    0/50 (0%)    0/50 (0%)    | 
|POLY-3 RATE (b)    |     0/46.53      0/46.69      0/41.84      0/45.34     |2/45.86      0/45.87      0/45.87      0/46.46      | 
|POLY-3 PERCENT (g) |     0.0%         0.0%         0.0%         0.0%        |4.4%         0.0%         0.0%         0.0%         | 
|TERMINAL (d)       |     0/40 (0%)    0/42 (0%)    0/35 (0%)    0/37 (0%)   |1/35 (3%)    0/37 (0%)    0/39 (0%)    0/38 (0%)    | 
|FIRST INCIDENCE    |     ---          ---          ---          ---         |368          ---          ---          ---          | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     (e)          (e)          (e)          (e)         |P=0.112N     P=0.234N     P=0.228N     P=0.231N     | 
|POLY 3             |     (e)          (e)          (e)          (e)         |P=0.114N     P=0.237N     P=0.237N     P=0.234N     | 
|POLY 1.5           |     (e)          (e)          (e)          (e)         |P=0.114N     P=0.238N     P=0.238N     P=0.236N     | 
|POLY 6             |     (e)          (e)          (e)          (e)         |P=0.114N     P=0.237N     P=0.236N     P=0.231N     | 
|LOGISTIC REGRESSION|     (e)          (e)          (e)          (e)         |P=0.121N     P=0.216N     P=0.224N     P=0.291N     | 
|COCH-ARM / FISHERS |     (e)          (e)          (e)          (e)         |P=0.115N     P=0.247N     P=0.247N     P=0.247N     | 
|ORDER RESTRICTED   |     (e)          (e)          (e)          (e)         |P=0.029N*    (e)          (e)          (e)          | 
|=================================================================================================================================| 
                                                                                                                                   
       Date:  04/29/04                           EXPERIMENT: 97006 TEST: 02                                            Page 25      
                     Statistical Analysis of Non-neoplastic Lesions in       Mice(B6C3F1)  -                  METHYL ISOBUTYL KETONE
                                         Terminal Sacrifice at 105 weeks                                                            
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Stomach, Glandular: Artery                                                                                                       | 
|     Inflammation Chronic                                                                                                        | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     0/49 (0%)    0/49 (0%)    0/49 (0%)    0/49 (0%)   |2/49 (4%)    0/50 (0%)    0/48 (0%)    0/49 (0%)    | 
|POLY-3 RATE (b)    |     0/46.24      0/46.69      0/41.84      0/45.12     |2/44.54      0/45.87      0/44.28      0/46.37      | 
|POLY-3 PERCENT (g) |     0.0%         0.0%         0.0%         0.0%        |4.5%         0.0%         0.0%         0.0%         | 
|TERMINAL (d)       |     0/40 (0%)    0/42 (0%)    0/35 (0%)    0/37 (0%)   |1/35 (3%)    0/37 (0%)    0/39 (0%)    0/38 (0%)    | 
|FIRST INCIDENCE    |     ---          ---          ---          ---         |681          ---          ---          ---          | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     (e)          (e)          (e)          (e)         |P=0.110N     P=0.234N     P=0.228N     P=0.226N     | 
|POLY 3             |     (e)          (e)          (e)          (e)         |P=0.116N     P=0.231N     P=0.238N     P=0.228N     | 
|POLY 1.5           |     (e)          (e)          (e)          (e)         |P=0.116N     P=0.231N     P=0.240N     P=0.231N     | 
|POLY 6             |     (e)          (e)          (e)          (e)         |P=0.116N     P=0.231N     P=0.237N     P=0.226N     | 
|LOGISTIC REGRESSION|     (e)          (e)          (e)          (e)         |P=0.115N     P=0.232N     P=0.241N     P=0.235N     | 
|COCH-ARM / FISHERS |     (e)          (e)          (e)          (e)         |P=0.116N     P=0.242N     P=0.253N     P=0.247N     | 
|ORDER RESTRICTED   |     (e)          (e)          (e)          (e)         |P=0.026N*    (e)          (e)          (e)          | 
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Testes                                                                                                                           | 
|     Atrophy                                                                                                                     | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     2/50 (4%)    2/50 (4%)    3/50 (6%)    1/50 (2%)   |                                                    | 
|POLY-3 RATE (b)    |     2/46.63      2/47.50      3/42.28      1/45.54     |                                                    | 
|POLY-3 PERCENT (g) |     4.3%         4.2%         7.1%         2.2%        |                                                    | 
|TERMINAL (d)       |     1/40 (3%)    2/42 (5%)    3/35 (9%)    0/37 (0%)   |                                                    | 
|FIRST INCIDENCE    |     704          729 (T)      729 (T)      678         |                                                    | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     P=0.446N     P=0.674N     P=0.440      P=0.515N    |                                                    | 
|POLY 3             |     P=0.421N     P=0.687N     P=0.456      P=0.508N    |                                                    | 
|POLY 1.5           |     P=0.415N     P=0.690N     P=0.468      P=0.505N    |                                                    | 
|POLY 6             |     P=0.427N     P=0.682N     P=0.446      P=0.511N    |                                                    | 
|LOGISTIC REGRESSION|     P=0.427N     P=0.682N     P=0.446      P=0.499N    |                                                    | 
|COCH-ARM / FISHERS |     P=0.404N     P=0.691N     P=0.500      P=0.500N    |                                                    | 
|ORDER RESTRICTED   |     P=0.391N     (e)          (e)          (e)         |                                                    | 
|=================================================================================================================================| 
                                                                                                                                   
       Date:  04/29/04                           EXPERIMENT: 97006 TEST: 02                                            Page 26      
                     Statistical Analysis of Non-neoplastic Lesions in       Mice(B6C3F1)  -                  METHYL ISOBUTYL KETONE
                                         Terminal Sacrifice at 105 weeks                                                            
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Testes: Interstitial Cell                                                                                                        | 
|     Hyperplasia                                                                                                                 | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     1/50 (2%)    0/50 (0%)    1/50 (2%)    2/50 (4%)   |                                                    | 
|POLY-3 RATE (b)    |     1/46.53      0/47.50      1/42.28      2/45.34     |                                                    | 
|POLY-3 PERCENT (g) |     2.2%         0.0%         2.4%         4.4%        |                                                    | 
|TERMINAL (d)       |     1/40 (3%)    0/42 (0%)    1/35 (3%)    2/37 (5%)   |                                                    | 
|FIRST INCIDENCE    |     729 (T)      ---          729 (T)      729 (T)     |                                                    | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     P=0.221      P=0.490N     P=0.732      P=0.473     |                                                    | 
|POLY 3             |     P=0.237      P=0.496N     P=0.739      P=0.491     |                                                    | 
|POLY 1.5           |     P=0.242      P=0.498N     P=0.745      P=0.494     |                                                    | 
|POLY 6             |     P=0.233      P=0.493N     P=0.734      P=0.488     |                                                    | 
|LOGISTIC REGRESSION|     P=0.221      (e)          P=0.732      P=0.473     |                                                    | 
|COCH-ARM / FISHERS |     P=0.247      P=0.500N     P=0.753N     P=0.500     |                                                    | 
|ORDER RESTRICTED   |     P=0.215      (e)          (e)          (e)         |                                                    | 
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Thyroid Gland: Follicular Cell                                                                                                   | 
|     Hyperplasia                                                                                                                 | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |     4/50 (8%)    4/49 (8%)    6/50 (12%)   8/50 (16%)  |7/50 (14%)   5/50 (10%)   11/49 (22%)  8/48 (17%)   | 
|POLY-3 RATE (b)    |     4/46.53      4/46.71      6/42.72      8/45.36     |7/45.48      5/46.26      11/45.63     8/44.99      | 
|POLY-3 PERCENT (g) |     8.6%         8.6%         14.1%        17.6%       |15.4%        10.8%        24.1%        17.8%        | 
|TERMINAL (d)       |     4/40 (10%)   3/42 (7%)    5/35 (14%)   7/37 (19%)  |6/35 (17%)   4/37 (11%)   9/38 (24%)   6/37 (16%)   | 
|FIRST INCIDENCE    |     729 (T)      724          602          725         |586          620          567          617          | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |     P=0.067      P=0.614N     P=0.288      P=0.144     |P=0.346      P=0.343N     P=0.271      P=0.545      | 
|POLY 3             |     P=0.085      P=0.641N     P=0.317      P=0.164     |P=0.296      P=0.367N     P=0.217      P=0.491      | 
|POLY 1.5           |     P=0.090      P=0.639      P=0.331      P=0.169     |P=0.289      P=0.372N     P=0.211      P=0.483      | 
|POLY 6             |     P=0.079      P=0.631N     P=0.308      P=0.159     |P=0.311      P=0.364N     P=0.223      P=0.506      | 
|LOGISTIC REGRESSION|     P=0.079      P=0.610N     P=0.305      P=0.154     |P=0.286      P=0.373N     P=0.209      P=0.483      | 
|COCH-ARM / FISHERS |     P=0.100      P=0.631      P=0.370      P=0.178     |P=0.275      P=0.380N     P=0.204      P=0.465      | 
|ORDER RESTRICTED   |     P=0.140      (e)          (e)          (e)         |P=0.254      (e)          (e)          (e)          | 
|=================================================================================================================================| 
                                                                                                                                   
       Date:  04/29/04                           EXPERIMENT: 97006 TEST: 02                                            Page 27      
                     Statistical Analysis of Non-neoplastic Lesions in       Mice(B6C3F1)  -                  METHYL ISOBUTYL KETONE
                                         Terminal Sacrifice at 105 weeks                                                            
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Uterus                                                                                                                           | 
|     Angiectasis                                                                                                                 | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |                                                        |1/50 (2%)    2/50 (4%)    1/49 (2%)    2/50 (4%)    | 
|POLY-3 RATE (b)    |                                                        |1/44.99      2/45.87      1/45.09      2/46.46      | 
|POLY-3 PERCENT (g) |                                                        |2.2%         4.4%         2.2%         4.3%         | 
|TERMINAL (d)       |                                                        |1/35 (3%)    2/37 (5%)    1/39 (3%)    2/38 (5%)    | 
|FIRST INCIDENCE    |                                                        |731 (T)      731 (T)      731 (T)      731 (T)      | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |                                                        |P=0.472      P=0.519      P=0.738N     P=0.529      | 
|POLY 3             |                                                        |P=0.456      P=0.507      P=0.760N     P=0.511      | 
|POLY 1.5           |                                                        |P=0.452      P=0.504      P=0.759      P=0.508      | 
|POLY 6             |                                                        |P=0.463      P=0.508      P=0.758N     P=0.517      | 
|LOGISTIC REGRESSION|                                                        |P=0.472      P=0.519      P=0.738N     P=0.529      | 
|COCH-ARM / FISHERS |                                                        |P=0.444      P=0.500      P=0.747      P=0.500      | 
|ORDER RESTRICTED   |                                                        |P=0.457      (e)          (e)          (e)          | 
|=================================================================================================================================| 
|                   |                                                        |                                                    | 
|                   |                              Males                     |                       Females                      | 
|Dose               |     CONTROL      450 PPM      900 PPM      1800 PPM    |CONTROL      450 PPM      900 PPM      1800 PPM     | 
|                   |                                                        |                                                    | 
|=================================================================================================================================| 
|                                                                                                                                 | 
|Uterus: Endometrium                                                                                                              | 
|     Hyperplasia Cystic                                                                                                          | 
|                                                                                                                                 | 
|                                                                                                                                 | 
|---------------------------------------------------------------------------------------------------------------------------------| 
|LESION RATES       |                                                        |                                                    | 
|-----------        |                                                        |                                                    | 
|OVERALL (a)        |                                                        |49/50 (98%)  48/50 (96%)  46/49 (94%)  49/50 (98%)  | 
|POLY-3 RATE (b)    |                                                        |49/49.01     48/49.00     46/47.68     49/50.00     | 
|POLY-3 PERCENT (g) |                                                        |100.0%       98.0%        96.5%        98.0%        | 
|TERMINAL (d)       |                                                        |35/35 (100%) 36/37 (97%)  39/39 (100%) 37/38 (97%)  | 
|FIRST INCIDENCE    |                                                        |368          515          530          329          | 
|-------------------|                                                        |                                                    | 
|STATISTICAL TESTS  |                                                        |                                                    | 
|-------------------|                                                        |                                                    | 
|LIFE TABLE         |                                                        |P=0.260N     P=0.331N     P=0.088N     P=0.298N     | 
|POLY 3             |                                                        |P=0.381N     P=0.506N     P=0.279N     P=0.510N     | 
|POLY 1.5           |                                                        |P=0.404N     P=0.545N     P=0.275N     P=0.551N     | 
|POLY 6             |                                                        |P=0.379N     P=0.500N     P=0.332N     P=0.504N     | 
|LOGISTIC REGRESSION|                                                        |P=0.513N     P=0.465N     P=0.200N     P=0.673N     | 
|COCH-ARM / FISHERS |                                                        |P=0.578      P=0.500N     P=0.301N     P=0.753N     | 
|ORDER RESTRICTED   |                                                        |P=0.239N     (e)          (e)          (e)          | 
|=================================================================================================================================| 
(a)  Number of tumor-bearing animals /  number of animals examined at site.                                                         
(b)  Number of tumor-bearing animals / Poly-3 number                                                                                
(d)  Observed incidence at terminal kill.                                                                                           
                                                                                                                                   
(f)  Beneath the control incidence are the P-values associated with the trend                                                       
test.  Beneath the dosed group incidence are the P-values corresponding to                                                          
pairwise comparisons between the controls and that dosed group.  The life                                                           
table analysis regards tumors in animals dying prior to  terminal kill as                                                           
 being (directly or indirectly) the cause of death.                                                                                 
Logistic regression is an alternative                                                                                               
 method for analyzing the incidence of non-fatal tumors. The Cochran-Armitage                                                       
and Fishers exact tests compare directly the overall incidence rates                                                                
For all tests a negative trend is indicated by N                                                                                    
(e)  Value of Statistic cannot be computed.                                                                                         
(g)  Poly-3 adjusted lifetime tumor incidence.                                                                                      
(I)  Interim sacrifice                                                                                                              
(T)  Terminal sacrifice                                                                                                             
#   Tumor rates based on number of animals necropsied.                                                                              
*   To the right of any statistical result, indicates significance at (P<=0.05).                                                    
**  To the right of any statistical result, indicates significance at (P<=0.01).                                                    
NTP is located at the National Institute of Environmental Health Sciences, part of the National Institutes of Health.