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TDMS Study 60968-01 Pathology Tables

NTP                                        STATISTICAL ANALYSIS OF PRIMARY TUMORS                              REPORT: PEIRPT08     
LAB: Battelle Northwest                                     ISOBUTYRALDEHYDE                                   DATE: 08/06/96       
EXPERIMENT: 60968 TEST: 01                                                                                     TIME: 16:54:50       
TEST TYPE:  CHRONIC                             CAGES FROM 0000 TO LAST CAGE                                   PAGE:       1        
CONT: N01-ES-95241                              ROUTE: RESPIRATORY EXPOSURE WHOLE BODY                         NTP C#: 60968B       
PATHOLOGIST: R. RENNE                        RENNE, R.                                                         CAS: 0078-84-2       
------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                                    
                                                             CORE STUDY                                                             
                                                                                                                                    
               REASONS FOR REMOVAL:    ALL                                                                                          
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
               REMOVAL DATE RANGE:     ALL                                                                                          
                                                                                                                                    
               TREATMENT GROUPS:       INCLUDE ALL                                                                                  
NTP                                        STATISTICAL ANALYSIS OF PRIMARY TUMORS                              REPORT: PEIRPT08     
LAB: Battelle Northwest                                     ISOBUTYRALDEHYDE                                   DATE: 08/06/96       
EXPERIMENT: 60968 TEST: 01                                                                                     TIME: 16:54:50       
TEST TYPE:  CHRONIC                             CAGES FROM 0000 TO LAST CAGE                                                        
CONT: N01-ES-95241                              ROUTE: RESPIRATORY EXPOSURE WHOLE BODY                         NTP C#: 60968B       
PATHOLOGIST: R. RENNE                        RENNE, R.                                                         CAS: 0078-84-2       


                                                    RATS(FISCHER344)
                                              ----------------------------
             FOR ALL DOSES THE TUMOR RATES IN THE FOLLOWING TISSUES/ORGANS ARE BASED ON NUMBER OF TISSUES EXAMINED.
             IN OTHER TISSUES/ORGANS, RATES ARE BASED ON NUMBER OF ANIMALS NECROPSIED.
                                                                    
                                                    ----------------
                                                    Adrenal Cortex
                                                    Adrenal Medulla
                                                    Bone Marrow
                                                    Brain
                                                    Clitoral Gland
                                                    Clitoral/Preputial Gland
                                                    Epididymis
                                                    Heart
                                                    Islets, Pancreatic
                                                    Kidney
                                                    Larynx
                                                    Liver
                                                    Lung
                                                    Nose
                                                    Ovary
                                                    Pancreas
                                                    Parathyroid Gland
                                                    Pituitary Gland
                                                    Preputial Gland
                                                    Prostate
                                                    Salivary Glands
                                                    Spleen
                                                    Testes
                                                    Thymus
                                                    Thyroid Gland
                                                    Urinary Bladder
NTP                                        STATISTICAL ANALYSIS OF PRIMARY TUMORS                              REPORT: PEIRPT08     
LAB: Battelle Northwest                                     ISOBUTYRALDEHYDE                                   DATE: 08/06/96       
EXPERIMENT: 60968 TEST: 01                                                                                     TIME: 16:54:50       
TEST TYPE:  CHRONIC                             CAGES FROM 0000 TO LAST CAGE                                                        
CONT: N01-ES-95241                              ROUTE: RESPIRATORY EXPOSURE WHOLE BODY                         NTP C#: 60968B       
PATHOLOGIST: R. RENNE                        RENNE, R.                                                         CAS: 0078-84-2       


                                     SUMMARY OF STATISTICALLY SIGNIFICANT (P<=.05) RESULTS
                                        IN THE ANALYSIS OF THE STUDY OF ISOBUTYRALDEHYDE
              ====================================================================================================
                                                           MALE RATS
                                                          -------------
                  ORGAN                               MORPHOLOGY
                 -------                             ------------
              Pituitary Gland: Pars Distalis or Unspecified Site
                                            Adenoma
                                            Carcinoma or Adenoma
              Testes                        Adenoma
              All Organs                    Leukemia: Lymphocytic, Monocytic, Mononuclear, or Undifferentiated
              ====================================================================================================
                                                           FEMALE RATS
                                                          -------------
                  ORGAN                               MORPHOLOGY
                 -------                             ------------
              Skin: Sebaceous Gland         Adenoma
              All Organs                    Leukemia: Lymphocytic, Monocytic, Mononuclear, or Undifferentiated
                                            Benign Tumors
                                            Malignant Tumors
              ====================================================================================================
         DATE: 08/06/96                     EXPERIMENT: 60968 TEST: 01                                                 PAGE   1
                            STATISTICAL ANALYSIS OF PRIMARY TUMORS IN RATS(FISCHER344) -- ISOBUTYRALDEHYDE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      500 PPM      1000 PPM     2000 PPM  |   CONTROL      500 PPM      1000 PPM     2000 PPM  |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Adrenal Cortex                                                                                                                   |
|     Adenoma                                                                                                                     |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  0/50 (0%)    0/49 (0%)    0/50 (0%)    0/50 (0%)  |  1/49 (2%)    0/49 (0%)    1/50 (2%)    2/50 (4%)  |
|ADJUSTED (b)           |   0.0%         0.0%         0.0%         0.0%      |   3.7%         0.0%         4.2%         6.3%      |
|TERMINAL (d)           |  0/12 (0%)    0/15 (0%)    0/11 (0%)    0/10 (0%)  |  1/27 (4%)    0/24 (0%)    1/24 (4%)    2/32 (6%)  |
|FIRST INCIDENCE (DAYS) |   ---          ---          ---          ---       |   734 (T)      ---          734 (T)      734 (T)   |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |    (e)          (e)          (e)          (e)      |  P=0.309      P=0.523N     P=0.736      P=0.560    |
|INCIDENTAL TUMOR       |    (e)          (e)          (e)          (e)      |  P=0.309      P=0.523N     P=0.736      P=0.560    |
|LOGISTIC REGRESSION    |    (e)          (e)          (e)          (e)      |  P=0.309      P=0.523N     P=0.736      P=0.560    |
|COCHRAN-ARMITAGE       |    (e)                                             |  P=0.253                                           |
|FISHER EXACT           |                 (e)          (e)          (e)      |               P=0.500N     P=0.747N     P=0.508    |
|=================================================================================================================================|
|                                                                                                                                 |
|Adrenal Medulla                                                                                                                  |
|     Pheochromocytoma Benign                                                                                                     |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            | 11/49 (22%)  12/49 (24%)  12/50 (24%)  15/50 (30%) |  1/49 (2%)    0/49 (0%)    2/47 (4%)    0/49 (0%)  |
|ADJUSTED (b)           |  59.1%        57.3%        60.7%        67.3%      |   3.7%         0.0%         8.7%         0.0%      |
|TERMINAL (d)           |  5/12 (42%)   7/15 (47%)   5/11 (45%)   4/10 (40%) |  1/27 (4%)    0/24 (0%)    2/23 (9%)    0/32 (0%)  |
|FIRST INCIDENCE (DAYS) |   663          579          523          581       |   734 (T)      ---          734 (T)      ---       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.051      P=0.513N     P=0.392      P=0.094    |  P=0.411N     P=0.523N     P=0.444      P=0.466N   |
|INCIDENTAL TUMOR       |  P=0.070      P=0.559      P=0.333      P=0.088    |  P=0.411N     P=0.523N     P=0.444      P=0.466N   |
|LOGISTIC REGRESSION    |  P=0.059      P=0.585      P=0.340      P=0.084    |  P=0.411N     P=0.523N     P=0.444      P=0.466N   |
|COCHRAN-ARMITAGE       |  P=0.224                                           |  P=0.462N                                          |
|FISHER EXACT           |               P=0.500      P=0.522      P=0.266    |               P=0.500N     P=0.484      P=0.500N   |
|=================================================================================================================================|
         DATE: 08/06/96                     EXPERIMENT: 60968 TEST: 01                                                 PAGE   2
                            STATISTICAL ANALYSIS OF PRIMARY TUMORS IN RATS(FISCHER344) -- ISOBUTYRALDEHYDE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      500 PPM      1000 PPM     2000 PPM  |   CONTROL      500 PPM      1000 PPM     2000 PPM  |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Adrenal Medulla                                                                                                                  |
|     Pheochromocytoma Malignant                                                                                                  |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  3/49 (6%)    0/49 (0%)    1/50 (2%)    1/50 (2%)  |  0/49 (0%)    0/49 (0%)    0/47 (0%)    1/49 (2%)  |
|ADJUSTED (b)           |  12.8%         0.0%         3.6%         2.9%      |   0.0%         0.0%         0.0%         2.0%      |
|TERMINAL (d)           |  0/12 (0%)    0/15 (0%)    0/11 (0%)    0/10 (0%)  |  0/27 (0%)    0/24 (0%)    0/23 (0%)    0/32 (0%)  |
|FIRST INCIDENCE (DAYS) |   642          ---          616          582       |   ---          ---          ---          471       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.380N     P=0.116N     P=0.380N     P=0.411N   |  P=0.205        (e)          (e)        P=0.517    |
|INCIDENTAL TUMOR       |  P=0.305N     P=0.139N     P=0.379N     P=0.327N   |  P=0.159        (e)          (e)        P=0.398    |
|LOGISTIC REGRESSION    |  P=0.296N     P=0.115N     P=0.321N     P=0.313N   |  P=0.089        (e)          (e)        P=0.333    |
|COCHRAN-ARMITAGE       |  P=0.290N                                          |  P=0.199                                           |
|FISHER EXACT           |               P=0.121N     P=0.301N     P=0.301N   |                 (e)          (e)        P=0.500    |
|=================================================================================================================================|
|                                                                                                                                 |
|Adrenal Medulla                                                                                                                  |
|     Pheochromocytoma: Benign, Complex, Malignant, NOS                                                                           |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            | 14/49 (29%)  12/49 (24%)  12/50 (24%)  16/50 (32%) |  1/49 (2%)    0/49 (0%)    2/47 (4%)    1/49 (2%)  |
|ADJUSTED (b)           |  64.5%        57.3%        60.7%        68.3%      |   3.7%         0.0%         8.7%         2.0%      |
|TERMINAL (d)           |  5/12 (42%)   7/15 (47%)   5/11 (45%)   4/10 (40%) |  1/27 (4%)    0/24 (0%)    2/23 (9%)    0/32 (0%)  |
|FIRST INCIDENCE (DAYS) |   642          579          523          581       |   734 (T)      ---          734 (T)      471       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.093      P=0.260N     P=0.542N     P=0.176    |  P=0.551      P=0.523N     P=0.444      P=0.732N   |
|INCIDENTAL TUMOR       |  P=0.134      P=0.364N     P=0.586      P=0.196    |  P=0.513      P=0.523N     P=0.444      P=0.726    |
|LOGISTIC REGRESSION    |  P=0.121      P=0.320N     P=0.577N     P=0.205    |  P=0.486      P=0.523N     P=0.444      P=0.716    |
|COCHRAN-ARMITAGE       |  P=0.340                                           |  P=0.499                                           |
|FISHER EXACT           |               P=0.410N     P=0.387N     P=0.440    |               P=0.500N     P=0.484      P=0.753N   |
|=================================================================================================================================|
         DATE: 08/06/96                     EXPERIMENT: 60968 TEST: 01                                                 PAGE   3
                            STATISTICAL ANALYSIS OF PRIMARY TUMORS IN RATS(FISCHER344) -- ISOBUTYRALDEHYDE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      500 PPM      1000 PPM     2000 PPM  |   CONTROL      500 PPM      1000 PPM     2000 PPM  |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Clitoral/Preputial Gland                                                                                                         |
|     Adenoma                                                                                                                     |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  0/50 (0%)    2/49 (4%)    1/50 (2%)    0/50 (0%)  |  1/48 (2%)    2/50 (4%)    0/50 (0%)    1/48 (2%)  |
|ADJUSTED (b)           |   0.0%        11.3%         3.1%         0.0%      |   3.7%         7.7%         0.0%         3.3%      |
|TERMINAL (d)           |  0/12 (0%)    1/15 (7%)    0/11 (0%)    0/10 (0%)  |  1/27 (4%)    1/24 (4%)    0/24 (0%)    1/30 (3%)  |
|FIRST INCIDENCE (DAYS) |   ---          692          586          ---       |   734 (T)      705          ---          734 (T)   |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.539N     P=0.264      P=0.471        (e)      |  P=0.457N     P=0.464      P=0.523N     P=0.739N   |
|INCIDENTAL TUMOR       |  P=0.496N     P=0.243      P=0.500        (e)      |  P=0.464N     P=0.534      P=0.523N     P=0.739N   |
|LOGISTIC REGRESSION    |  P=0.489N     P=0.254      P=0.510        (e)      |  P=0.479N     P=0.495      P=0.523N     P=0.739N   |
|COCHRAN-ARMITAGE       |  P=0.459N                                          |  P=0.503N                                          |
|FISHER EXACT           |               P=0.242      P=0.500        (e)      |               P=0.515      P=0.490N     P=0.753N   |
|=================================================================================================================================|
|                                                                                                                                 |
|Clitoral/Preputial Gland                                                                                                         |
|     Carcinoma                                                                                                                   |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  2/50 (4%)    2/49 (4%)    4/50 (8%)    3/50 (6%)  |  4/48 (8%)    5/50 (10%)   4/50 (8%)    3/48 (6%)  |
|ADJUSTED (b)           |  14.9%         8.6%        16.6%        20.9%      |  13.9%        17.1%        16.7%        10.0%      |
|TERMINAL (d)           |  1/12 (8%)    1/15 (7%)    1/11 (9%)    1/10 (10%) |  3/27 (11%)   3/24 (13%)   4/24 (17%)   3/30 (10%) |
|FIRST INCIDENCE (DAYS) |   720          384          419          652       |   690          544          734 (T)      734 (T)   |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.262      P=0.641N     P=0.297      P=0.379    |  P=0.297N     P=0.454      P=0.592      P=0.448N   |
|INCIDENTAL TUMOR       |  P=0.386      P=0.674      P=0.432      P=0.378    |  P=0.301N     P=0.489      P=0.644N     P=0.440N   |
|LOGISTIC REGRESSION    |  P=0.362      P=0.687      P=0.339      P=0.390    |  P=0.324N     P=0.535      P=0.638N     P=0.470N   |
|COCHRAN-ARMITAGE       |  P=0.360                                           |  P=0.366N                                          |
|FISHER EXACT           |               P=0.684      P=0.339      P=0.500    |               P=0.526      P=0.619N     P=0.500N   |
|=================================================================================================================================|
         DATE: 08/06/96                     EXPERIMENT: 60968 TEST: 01                                                 PAGE   4
                            STATISTICAL ANALYSIS OF PRIMARY TUMORS IN RATS(FISCHER344) -- ISOBUTYRALDEHYDE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      500 PPM      1000 PPM     2000 PPM  |   CONTROL      500 PPM      1000 PPM     2000 PPM  |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Clitoral/Preputial Gland                                                                                                         |
|     Carcinoma or Adenoma                                                                                                        |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  2/50 (4%)    4/49 (8%)    5/50 (10%)   3/50 (6%)  |  5/48 (10%)   7/50 (14%)   4/50 (8%)    4/48 (8%)  |
|ADJUSTED (b)           |  14.9%        19.3%        19.2%        20.9%      |  17.5%        24.0%        16.7%        13.3%      |
|TERMINAL (d)           |  1/12 (8%)    2/15 (13%)   1/11 (9%)    1/10 (10%) |  4/27 (15%)   4/24 (17%)   4/24 (17%)   4/30 (13%) |
|FIRST INCIDENCE (DAYS) |   720          384          419          652       |   690          544          734 (T)      734 (T)   |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.335      P=0.401      P=0.184      P=0.379    |  P=0.245N     P=0.326      P=0.562N     P=0.439N   |
|INCIDENTAL TUMOR       |  P=0.475      P=0.321      P=0.289      P=0.378    |  P=0.249N     P=0.386      P=0.504N     P=0.431N   |
|LOGISTIC REGRESSION    |  P=0.458      P=0.338      P=0.222      P=0.390    |  P=0.274N     P=0.413      P=0.495N     P=0.467N   |
|COCHRAN-ARMITAGE       |  P=0.467                                           |  P=0.320N                                          |
|FISHER EXACT           |               P=0.329      P=0.218      P=0.500    |               P=0.409      P=0.474N     P=0.500N   |
|=================================================================================================================================|
|                                                                                                                                 |
|Islets, Pancreatic                                                                                                               |
|     Adenoma                                                                                                                     |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  1/50 (2%)    3/49 (6%)    1/50 (2%)    3/50 (6%)  |  2/50 (4%)    1/48 (2%)    0/49 (0%)    1/50 (2%)  |
|ADJUSTED (b)           |   6.3%        10.4%         7.7%        18.5%      |   6.1%         4.2%         0.0%         3.1%      |
|TERMINAL (d)           |  0/12 (0%)    0/15 (0%)    0/11 (0%)    1/10 (10%) |  0/27 (0%)    1/24 (4%)    0/24 (0%)    1/32 (3%)  |
|FIRST INCIDENCE (DAYS) |   706          616          720          636       |   687          734 (T)      ---          734 (T)   |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.202      P=0.335      P=0.745      P=0.221    |  P=0.336N     P=0.521N     P=0.224N     P=0.477N   |
|INCIDENTAL TUMOR       |  P=0.243      P=0.262      P=0.670      P=0.252    |  P=0.334N     P=0.419N     P=0.091N     P=0.480N   |
|LOGISTIC REGRESSION    |  P=0.252      P=0.307      P=0.730      P=0.243    |  P=0.341N     P=0.502N     P=0.232N     P=0.476N   |
|COCHRAN-ARMITAGE       |  P=0.316                                           |  P=0.364N                                          |
|FISHER EXACT           |               P=0.301      P=0.753N     P=0.309    |               P=0.515N     P=0.253N     P=0.500N   |
|=================================================================================================================================|
         DATE: 08/06/96                     EXPERIMENT: 60968 TEST: 01                                                 PAGE   5
                            STATISTICAL ANALYSIS OF PRIMARY TUMORS IN RATS(FISCHER344) -- ISOBUTYRALDEHYDE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      500 PPM      1000 PPM     2000 PPM  |   CONTROL      500 PPM      1000 PPM     2000 PPM  |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Islets, Pancreatic                                                                                                               |
|     Carcinoma                                                                                                                   |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  2/50 (4%)    1/49 (2%)    1/50 (2%)    1/50 (2%)  |  0/50 (0%)    0/48 (0%)    0/49 (0%)    1/50 (2%)  |
|ADJUSTED (b)           |  13.2%         2.1%         9.1%        10.0%      |   0.0%         0.0%         0.0%         2.7%      |
|TERMINAL (d)           |  1/12 (8%)    0/15 (0%)    1/11 (9%)    1/10 (10%) |  0/27 (0%)    0/24 (0%)    0/24 (0%)    0/32 (0%)  |
|FIRST INCIDENCE (DAYS) |   695          540          733 (T)      733 (T)   |   ---          ---          ---          664       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.499N     P=0.467N     P=0.533N     P=0.596N   |  P=0.204        (e)          (e)        P=0.511    |
|INCIDENTAL TUMOR       |  P=0.423N     P=0.554N     P=0.567N     P=0.580N   |  P=0.160        (e)          (e)        P=0.500    |
|LOGISTIC REGRESSION    |  P=0.469N     P=0.503N     P=0.552N     P=0.602N   |  P=0.194        (e)          (e)        P=0.495    |
|COCHRAN-ARMITAGE       |  P=0.407N                                          |  P=0.201                                           |
|FISHER EXACT           |               P=0.508N     P=0.500N     P=0.500N   |                 (e)          (e)        P=0.500    |
|=================================================================================================================================|
|                                                                                                                                 |
|Islets, Pancreatic                                                                                                               |
|     Carcinoma or Adenoma                                                                                                        |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  3/50 (6%)    4/49 (8%)    2/50 (4%)    4/50 (8%)  |  2/50 (4%)    1/48 (2%)    0/49 (0%)    2/50 (4%)  |
|ADJUSTED (b)           |  18.6%        12.3%        16.1%        27.6%      |   6.1%         4.2%         0.0%         5.7%      |
|TERMINAL (d)           |  1/12 (8%)    0/15 (0%)    1/11 (9%)    2/10 (20%) |  0/27 (0%)    1/24 (4%)    0/24 (0%)    1/32 (3%)  |
|FIRST INCIDENCE (DAYS) |   695          540          720          636       |   687          734 (T)      ---          664       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.322      P=0.544      P=0.538N     P=0.358    |  P=0.610N     P=0.521N     P=0.224N     P=0.669N   |
|INCIDENTAL TUMOR       |  P=0.404      P=0.427      P=0.626N     P=0.397    |  P=0.620      P=0.419N     P=0.091N     P=0.685N   |
|LOGISTIC REGRESSION    |  P=0.388      P=0.500      P=0.571N     P=0.373    |  P=0.614      P=0.502N     P=0.232N     P=0.678N   |
|COCHRAN-ARMITAGE       |  P=0.484                                           |  P=0.594                                           |
|FISHER EXACT           |               P=0.489      P=0.500N     P=0.500    |               P=0.515N     P=0.253N     P=0.691N   |
|=================================================================================================================================|
         DATE: 08/06/96                     EXPERIMENT: 60968 TEST: 01                                                 PAGE   6
                            STATISTICAL ANALYSIS OF PRIMARY TUMORS IN RATS(FISCHER344) -- ISOBUTYRALDEHYDE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      500 PPM      1000 PPM     2000 PPM  |   CONTROL      500 PPM      1000 PPM     2000 PPM  |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Liver                                                                                                                            |
|     Hepatocellular Adenoma                                                                                                      |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  0/50 (0%)    0/49 (0%)    0/50 (0%)    0/50 (0%)  |  0/49 (0%)    1/50 (2%)    2/50 (4%)    0/50 (0%)  |
|ADJUSTED (b)           |   0.0%         0.0%         0.0%         0.0%      |   0.0%         4.2%         8.3%         0.0%      |
|TERMINAL (d)           |  0/12 (0%)    0/15 (0%)    0/11 (0%)    0/10 (0%)  |  0/27 (0%)    1/24 (4%)    2/24 (8%)    0/32 (0%)  |
|FIRST INCIDENCE (DAYS) |   ---          ---          ---          ---       |   ---          734 (T)      734 (T)      ---       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |    (e)          (e)          (e)          (e)      |  P=0.559N     P=0.477      P=0.212        (e)      |
|INCIDENTAL TUMOR       |    (e)          (e)          (e)          (e)      |  P=0.559N     P=0.477      P=0.212        (e)      |
|LOGISTIC REGRESSION    |    (e)          (e)          (e)          (e)      |  P=0.559N     P=0.477      P=0.212        (e)      |
|COCHRAN-ARMITAGE       |    (e)                                             |  P=0.612N                                          |
|FISHER EXACT           |                 (e)          (e)          (e)      |               P=0.505      P=0.253        (e)      |
|=================================================================================================================================|
|                                                                                                                                 |
|Liver                                                                                                                            |
|     Hepatocellular Carcinoma                                                                                                    |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  0/50 (0%)    2/49 (4%)    0/50 (0%)    0/50 (0%)  |  0/49 (0%)    0/50 (0%)    0/50 (0%)    0/50 (0%)  |
|ADJUSTED (b)           |   0.0%         8.0%         0.0%         0.0%      |   0.0%         0.0%         0.0%         0.0%      |
|TERMINAL (d)           |  0/12 (0%)    0/15 (0%)    0/11 (0%)    0/10 (0%)  |  0/27 (0%)    0/24 (0%)    0/24 (0%)    0/32 (0%)  |
|FIRST INCIDENCE (DAYS) |   ---          678          ---          ---       |   ---          ---          ---          ---       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.501N     P=0.240        (e)          (e)      |    (e)          (e)          (e)          (e)      |
|INCIDENTAL TUMOR       |  P=0.474N     P=0.197        (e)          (e)      |    (e)          (e)          (e)          (e)      |
|LOGISTIC REGRESSION    |  P=0.434N     P=0.242        (e)          (e)      |    (e)          (e)          (e)          (e)      |
|COCHRAN-ARMITAGE       |  P=0.404N                                          |    (e)                                             |
|FISHER EXACT           |               P=0.242        (e)          (e)      |                 (e)          (e)          (e)      |
|=================================================================================================================================|
         DATE: 08/06/96                     EXPERIMENT: 60968 TEST: 01                                                 PAGE   7
                            STATISTICAL ANALYSIS OF PRIMARY TUMORS IN RATS(FISCHER344) -- ISOBUTYRALDEHYDE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      500 PPM      1000 PPM     2000 PPM  |   CONTROL      500 PPM      1000 PPM     2000 PPM  |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Liver                                                                                                                            |
|     Hepatocellular Carcinoma or Hepatocellular Adenoma                                                                          |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  0/50 (0%)    2/49 (4%)    0/50 (0%)    0/50 (0%)  |  0/49 (0%)    1/50 (2%)    2/50 (4%)    0/50 (0%)  |
|ADJUSTED (b)           |   0.0%         8.0%         0.0%         0.0%      |   0.0%         4.2%         8.3%         0.0%      |
|TERMINAL (d)           |  0/12 (0%)    0/15 (0%)    0/11 (0%)    0/10 (0%)  |  0/27 (0%)    1/24 (4%)    2/24 (8%)    0/32 (0%)  |
|FIRST INCIDENCE (DAYS) |   ---          678          ---          ---       |   ---          734 (T)      734 (T)      ---       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.501N     P=0.240        (e)          (e)      |  P=0.559N     P=0.477      P=0.212        (e)      |
|INCIDENTAL TUMOR       |  P=0.474N     P=0.197        (e)          (e)      |  P=0.559N     P=0.477      P=0.212        (e)      |
|LOGISTIC REGRESSION    |  P=0.434N     P=0.242        (e)          (e)      |  P=0.559N     P=0.477      P=0.212        (e)      |
|COCHRAN-ARMITAGE       |  P=0.404N                                          |  P=0.612N                                          |
|FISHER EXACT           |               P=0.242        (e)          (e)      |               P=0.505      P=0.253        (e)      |
|=================================================================================================================================|
|                                                                                                                                 |
|Liver                                                                                                                            |
|     Hepatocellular Carcinoma, Hepatocellular Adenoma, or Hepatoblastoma                                                         |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  0/50 (0%)    2/49 (4%)    0/50 (0%)    0/50 (0%)  |  0/49 (0%)    1/50 (2%)    2/50 (4%)    0/50 (0%)  |
|ADJUSTED (b)           |   0.0%         8.0%         0.0%         0.0%      |   0.0%         4.2%         8.3%         0.0%      |
|TERMINAL (d)           |  0/12 (0%)    0/15 (0%)    0/11 (0%)    0/10 (0%)  |  0/27 (0%)    1/24 (4%)    2/24 (8%)    0/32 (0%)  |
|FIRST INCIDENCE (DAYS) |   ---          678          ---          ---       |   ---          734 (T)      734 (T)      ---       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.501N     P=0.240        (e)          (e)      |  P=0.559N     P=0.477      P=0.212        (e)      |
|INCIDENTAL TUMOR       |  P=0.474N     P=0.197        (e)          (e)      |  P=0.559N     P=0.477      P=0.212        (e)      |
|LOGISTIC REGRESSION    |  P=0.434N     P=0.242        (e)          (e)      |  P=0.559N     P=0.477      P=0.212        (e)      |
|COCHRAN-ARMITAGE       |  P=0.404N                                          |  P=0.612N                                          |
|FISHER EXACT           |               P=0.242        (e)          (e)      |               P=0.505      P=0.253        (e)      |
|=================================================================================================================================|
         DATE: 08/06/96                     EXPERIMENT: 60968 TEST: 01                                                 PAGE   8
                            STATISTICAL ANALYSIS OF PRIMARY TUMORS IN RATS(FISCHER344) -- ISOBUTYRALDEHYDE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      500 PPM      1000 PPM     2000 PPM  |   CONTROL      500 PPM      1000 PPM     2000 PPM  |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Lung                                                                                                                             |
|     Alveolar/Bronchiolar Adenoma                                                                                                |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  1/50 (2%)    0/49 (0%)    0/50 (0%)    2/50 (4%)  |  1/49 (2%)    0/50 (0%)    0/50 (0%)    3/50 (6%)  |
|ADJUSTED (b)           |   5.0%         0.0%         0.0%        13.5%      |   3.7%         0.0%         0.0%         8.3%      |
|TERMINAL (d)           |  0/12 (0%)    0/15 (0%)    0/11 (0%)    1/10 (10%) |  1/27 (4%)    0/24 (0%)    0/24 (0%)    1/32 (3%)  |
|FIRST INCIDENCE (DAYS) |   692          ---          ---          637       |   734 (T)      ---          ---          646       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.177      P=0.500N     P=0.521N     P=0.401    |  P=0.112      P=0.523N     P=0.523N     P=0.353    |
|INCIDENTAL TUMOR       |  P=0.219      P=0.536N     P=0.581N     P=0.464    |  P=0.092      P=0.523N     P=0.523N     P=0.360    |
|LOGISTIC REGRESSION    |  P=0.203      P=0.491N     P=0.527N     P=0.441    |  P=0.094      P=0.523N     P=0.523N     P=0.333    |
|COCHRAN-ARMITAGE       |  P=0.247                                           |  P=0.088                                           |
|FISHER EXACT           |               P=0.505N     P=0.500N     P=0.500    |               P=0.495N     P=0.495N     P=0.316    |
|=================================================================================================================================|
|                                                                                                                                 |
|Lung                                                                                                                             |
|     Alveolar/Bronchiolar Carcinoma or Alveolar/Bronchiolar Adenoma                                                              |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  1/50 (2%)    0/49 (0%)    0/50 (0%)    2/50 (4%)  |  2/49 (4%)    0/50 (0%)    0/50 (0%)    3/50 (6%)  |
|ADJUSTED (b)           |   5.0%         0.0%         0.0%        13.5%      |   7.4%         0.0%         0.0%         8.3%      |
|TERMINAL (d)           |  0/12 (0%)    0/15 (0%)    0/11 (0%)    1/10 (10%) |  2/27 (7%)    0/24 (0%)    0/24 (0%)    1/32 (3%)  |
|FIRST INCIDENCE (DAYS) |   692          ---          ---          637       |   734 (T)      ---          ---          646       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.177      P=0.500N     P=0.521N     P=0.401    |  P=0.298      P=0.264N     P=0.264N     P=0.560    |
|INCIDENTAL TUMOR       |  P=0.219      P=0.536N     P=0.581N     P=0.464    |  P=0.282      P=0.264N     P=0.264N     P=0.571    |
|LOGISTIC REGRESSION    |  P=0.203      P=0.491N     P=0.527N     P=0.441    |  P=0.270      P=0.264N     P=0.264N     P=0.542    |
|COCHRAN-ARMITAGE       |  P=0.247                                           |  P=0.249                                           |
|FISHER EXACT           |               P=0.505N     P=0.500N     P=0.500    |               P=0.242N     P=0.242N     P=0.510    |
|=================================================================================================================================|
         DATE: 08/06/96                     EXPERIMENT: 60968 TEST: 01                                                 PAGE   9
                            STATISTICAL ANALYSIS OF PRIMARY TUMORS IN RATS(FISCHER344) -- ISOBUTYRALDEHYDE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      500 PPM      1000 PPM     2000 PPM  |   CONTROL      500 PPM      1000 PPM     2000 PPM  |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Mammary Gland                                                                                                                    |
|     Carcinoma                                                                                                                   |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  0/50 (0%)    0/50 (0%)    0/50 (0%)    0/50 (0%)  |  1/50 (2%)    1/50 (2%)    6/50 (12%)   1/50 (2%)  |
|ADJUSTED (b)           |   0.0%         0.0%         0.0%         0.0%      |   3.7%         3.8%        19.7%         3.1%      |
|TERMINAL (d)           |  0/12 (0%)    0/15 (0%)    0/11 (0%)    0/10 (0%)  |  1/27 (4%)    0/24 (0%)    2/24 (8%)    1/32 (3%)  |
|FIRST INCIDENCE (DAYS) |   ---          ---          ---          ---       |   734 (T)      706          664          734 (T)   |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |    (e)          (e)          (e)          (e)      |  P=0.558      P=0.735      P=0.059      P=0.724N   |
|INCIDENTAL TUMOR       |    (e)          (e)          (e)          (e)      |  P=0.517      P=0.730N     P=0.138      P=0.724N   |
|LOGISTIC REGRESSION    |    (e)          (e)          (e)          (e)      |  P=0.521      P=0.762      P=0.071      P=0.724N   |
|COCHRAN-ARMITAGE       |    (e)                                             |  P=0.477                                           |
|FISHER EXACT           |                 (e)          (e)          (e)      |               P=0.753N     P=0.056      P=0.753N   |
|=================================================================================================================================|
|                                                                                                                                 |
|Mammary Gland                                                                                                                    |
|     Fibroadenoma                                                                                                                |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  1/50 (2%)    2/50 (4%)    1/50 (2%)    1/50 (2%)  | 27/50 (54%)  21/50 (42%)  24/50 (48%)  24/50 (48%) |
|ADJUSTED (b)           |   8.3%        10.0%         9.1%         4.3%      |  72.7%        68.0%        62.7%        66.5%      |
|TERMINAL (d)           |  1/12 (8%)    1/15 (7%)    1/11 (9%)    0/10 (0%)  | 17/27 (63%)  15/24 (63%)  11/24 (46%)  20/32 (63%) |
|FIRST INCIDENCE (DAYS) |   733 (T)      667          733 (T)      645       |   547          511          489          646       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.609      P=0.561      P=0.746      P=0.710    |  P=0.168N     P=0.275N     P=0.428N     P=0.143N   |
|INCIDENTAL TUMOR       |  P=0.618      P=0.531      P=0.746      P=0.703    |  P=0.238N     P=0.178N     P=0.170N     P=0.156N   |
|LOGISTIC REGRESSION    |  P=0.621N     P=0.530      P=0.746      P=0.726    |  P=0.275N     P=0.109N     P=0.210N     P=0.170N   |
|COCHRAN-ARMITAGE       |  P=0.531N                                          |  P=0.424N                                          |
|FISHER EXACT           |               P=0.500      P=0.753N     P=0.753N   |               P=0.158N     P=0.345N     P=0.345N   |
|=================================================================================================================================|
         DATE: 08/06/96                     EXPERIMENT: 60968 TEST: 01                                                 PAGE  10
                            STATISTICAL ANALYSIS OF PRIMARY TUMORS IN RATS(FISCHER344) -- ISOBUTYRALDEHYDE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      500 PPM      1000 PPM     2000 PPM  |   CONTROL      500 PPM      1000 PPM     2000 PPM  |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Mammary Gland                                                                                                                    |
|     Fibroma, Fibroadenoma, Carcinoma, or Adenoma                                                                                |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  1/50 (2%)    2/50 (4%)    1/50 (2%)    1/50 (2%)  | 27/50 (54%)  22/50 (44%)  29/50 (58%)  24/50 (48%) |
|ADJUSTED (b)           |   8.3%        10.0%         9.1%         4.3%      |  72.7%        69.2%        71.3%        66.5%      |
|TERMINAL (d)           |  1/12 (8%)    1/15 (7%)    1/11 (9%)    0/10 (0%)  | 17/27 (63%)  15/24 (63%)  13/24 (54%)  20/32 (63%) |
|FIRST INCIDENCE (DAYS) |   733 (T)      667          733 (T)      645       |   547          511          489          646       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.609      P=0.561      P=0.746      P=0.710    |  P=0.174N     P=0.348N     P=0.379      P=0.143N   |
|INCIDENTAL TUMOR       |  P=0.618      P=0.531      P=0.746      P=0.703    |  P=0.246N     P=0.225N     P=0.448N     P=0.156N   |
|LOGISTIC REGRESSION    |  P=0.621N     P=0.530      P=0.746      P=0.726    |  P=0.282N     P=0.151N     P=0.570N     P=0.170N   |
|COCHRAN-ARMITAGE       |  P=0.531N                                          |  P=0.443N                                          |
|FISHER EXACT           |               P=0.500      P=0.753N     P=0.753N   |               P=0.212N     P=0.420      P=0.345N   |
|=================================================================================================================================|
|                                                                                                                                 |
|Oral Cavity (Oral Mucosa, Tongue, Pharynx, Tooth, Gingiva)                                                                       |
|     Squamous Cell Carcinoma, Papilloma Squamous, or Papilloma                                                                   |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  0/50 (0%)    1/50 (2%)    1/50 (2%)    1/50 (2%)  |  1/50 (2%)    0/50 (0%)    1/50 (2%)    2/50 (4%)  |
|ADJUSTED (b)           |   0.0%         6.7%         9.1%         6.3%      |   3.7%         0.0%         3.3%         6.0%      |
|TERMINAL (d)           |  0/12 (0%)    1/15 (7%)    1/11 (9%)    0/10 (0%)  |  1/27 (4%)    0/24 (0%)    0/24 (0%)    1/32 (3%)  |
|FIRST INCIDENCE (DAYS) |   ---          733 (T)      733 (T)      678       |   734 (T)      ---          706          681       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.294      P=0.545      P=0.483      P=0.403    |  P=0.295      P=0.523N     P=0.751      P=0.543    |
|INCIDENTAL TUMOR       |  P=0.310      P=0.545      P=0.483      P=0.435    |  P=0.263      P=0.523N     P=0.690N     P=0.539    |
|LOGISTIC REGRESSION    |  P=0.301      P=0.545      P=0.483      P=0.474    |  P=0.270      P=0.523N     P=0.748N     P=0.531    |
|COCHRAN-ARMITAGE       |  P=0.384                                           |  P=0.247                                           |
|FISHER EXACT           |               P=0.500      P=0.500      P=0.500    |               P=0.500N     P=0.753N     P=0.500    |
|=================================================================================================================================|
         DATE: 08/06/96                     EXPERIMENT: 60968 TEST: 01                                                 PAGE  11
                            STATISTICAL ANALYSIS OF PRIMARY TUMORS IN RATS(FISCHER344) -- ISOBUTYRALDEHYDE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      500 PPM      1000 PPM     2000 PPM  |   CONTROL      500 PPM      1000 PPM     2000 PPM  |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Pituitary Gland: Pars Distalis or Unspecified Site                                                                               |
|     Adenoma                                                                                                                     |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            | 41/50 (82%)  27/49 (55%)  37/49 (76%)  34/50 (68%) | 34/48 (71%)  28/50 (56%)  33/49 (67%)  29/50 (58%) |
|ADJUSTED (b)           |  97.5%        78.9%        94.1%        93.1%      |  80.5%        73.9%        83.8%        72.2%      |
|TERMINAL (d)           | 11/12 (92%)   9/15 (60%)   9/11 (82%)   8/10 (80%) | 19/27 (70%)  15/24 (63%)  18/24 (75%)  21/32 (66%) |
|FIRST INCIDENCE (DAYS) |   465          384          479          468       |   400          551          487          511       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.232      P=0.010N*    P=0.492      P=0.529    |  P=0.088N     P=0.295N     P=0.554N     P=0.080N   |
|INCIDENTAL TUMOR       |  P=0.289N     P=0.003N**   P=0.424N     P=0.086N   |  P=0.148N     P=0.105N     P=0.320N     P=0.087N   |
|LOGISTIC REGRESSION    |  P=0.351N     P=0.002N**   P=0.345N     P=0.109N   |  P=0.145N     P=0.089N     P=0.355N     P=0.087N   |
|COCHRAN-ARMITAGE       |  P=0.279N                                          |  P=0.211N                                          |
|FISHER EXACT           |               P=0.004N**   P=0.294N     P=0.083N   |               P=0.094N     P=0.440N     P=0.132N   |
|=================================================================================================================================|
|                                                                                                                                 |
|Pituitary Gland: Pars Distalis or Unspecified Site                                                                               |
|     Carcinoma or Adenoma                                                                                                        |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            | 41/50 (82%)  27/49 (55%)  37/49 (76%)  34/50 (68%) | 34/48 (71%)  29/50 (58%)  33/49 (67%)  29/50 (58%) |
|ADJUSTED (b)           |  97.5%        78.9%        94.1%        93.1%      |  80.5%        74.7%        83.8%        72.2%      |
|TERMINAL (d)           | 11/12 (92%)   9/15 (60%)   9/11 (82%)   8/10 (80%) | 19/27 (70%)  15/24 (63%)  18/24 (75%)  21/32 (66%) |
|FIRST INCIDENCE (DAYS) |   465          384          479          468       |   400          551          487          511       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.232      P=0.010N*    P=0.492      P=0.529    |  P=0.080N     P=0.354N     P=0.554N     P=0.080N   |
|INCIDENTAL TUMOR       |  P=0.289N     P=0.003N**   P=0.424N     P=0.086N   |  P=0.130N     P=0.135N     P=0.320N     P=0.087N   |
|LOGISTIC REGRESSION    |  P=0.351N     P=0.002N**   P=0.345N     P=0.109N   |  P=0.127N     P=0.125N     P=0.355N     P=0.087N   |
|COCHRAN-ARMITAGE       |  P=0.279N                                          |  P=0.189N                                          |
|FISHER EXACT           |               P=0.004N**   P=0.294N     P=0.083N   |               P=0.132N     P=0.440N     P=0.132N   |
|=================================================================================================================================|
         DATE: 08/06/96                     EXPERIMENT: 60968 TEST: 01                                                 PAGE  12
                            STATISTICAL ANALYSIS OF PRIMARY TUMORS IN RATS(FISCHER344) -- ISOBUTYRALDEHYDE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      500 PPM      1000 PPM     2000 PPM  |   CONTROL      500 PPM      1000 PPM     2000 PPM  |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Skin                                                                                                                             |
|     Basal Cell Adenoma, Basosquamous Tumor Benign, or Trichoepithelioma                                                         |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  0/50 (0%)    2/50 (4%)    1/50 (2%)    0/50 (0%)  |  0/50 (0%)    0/50 (0%)    0/50 (0%)    1/50 (2%)  |
|ADJUSTED (b)           |   0.0%        13.3%         5.3%         0.0%      |   0.0%         0.0%         0.0%         3.1%      |
|TERMINAL (d)           |  0/12 (0%)    2/15 (13%)   0/11 (0%)    0/10 (0%)  |  0/27 (0%)    0/24 (0%)    0/24 (0%)    1/32 (3%)  |
|FIRST INCIDENCE (DAYS) |   ---          733 (T)      686          ---       |   ---          ---          ---          734 (T)   |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.555N     P=0.286      P=0.480        (e)      |  P=0.233        (e)          (e)        P=0.534    |
|INCIDENTAL TUMOR       |  P=0.536N     P=0.286      P=0.419        (e)      |  P=0.233        (e)          (e)        P=0.534    |
|LOGISTIC REGRESSION    |  P=0.546N     P=0.286      P=0.475        (e)      |  P=0.233        (e)          (e)        P=0.534    |
|COCHRAN-ARMITAGE       |  P=0.461N                                          |  P=0.198                                           |
|FISHER EXACT           |               P=0.247      P=0.500        (e)      |                 (e)          (e)        P=0.500    |
|=================================================================================================================================|
|                                                                                                                                 |
|Skin                                                                                                                             |
|     Basal Cell Carcinoma, Basal Cell Adenoma, Basosquamous Tumor (benign,                                                       |
|     malignant or NOS), or Trichoepithelioma                                                                                     |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  0/50 (0%)    2/50 (4%)    1/50 (2%)    0/50 (0%)  |  0/50 (0%)    0/50 (0%)    0/50 (0%)    1/50 (2%)  |
|ADJUSTED (b)           |   0.0%        13.3%         5.3%         0.0%      |   0.0%         0.0%         0.0%         3.1%      |
|TERMINAL (d)           |  0/12 (0%)    2/15 (13%)   0/11 (0%)    0/10 (0%)  |  0/27 (0%)    0/24 (0%)    0/24 (0%)    1/32 (3%)  |
|FIRST INCIDENCE (DAYS) |   ---          733 (T)      686          ---       |   ---          ---          ---          734 (T)   |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.555N     P=0.286      P=0.480        (e)      |  P=0.233        (e)          (e)        P=0.534    |
|INCIDENTAL TUMOR       |  P=0.536N     P=0.286      P=0.419        (e)      |  P=0.233        (e)          (e)        P=0.534    |
|LOGISTIC REGRESSION    |  P=0.546N     P=0.286      P=0.475        (e)      |  P=0.233        (e)          (e)        P=0.534    |
|COCHRAN-ARMITAGE       |  P=0.461N                                          |  P=0.198                                           |
|FISHER EXACT           |               P=0.247      P=0.500        (e)      |                 (e)          (e)        P=0.500    |
|=================================================================================================================================|
         DATE: 08/06/96                     EXPERIMENT: 60968 TEST: 01                                                 PAGE  13
                            STATISTICAL ANALYSIS OF PRIMARY TUMORS IN RATS(FISCHER344) -- ISOBUTYRALDEHYDE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      500 PPM      1000 PPM     2000 PPM  |   CONTROL      500 PPM      1000 PPM     2000 PPM  |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Skin                                                                                                                             |
|     Basal or Sq. Cell Carcinoma, Carcinoma, Basosq. Tumor (M or B), Basal                                                       |
|     Cell Adenoma, Adenoma, Papilloma, Sq Papilloma, Keratoacanthoma, Trichoepithelioma                                          |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  2/50 (4%)    7/50 (14%)   4/50 (8%)    2/50 (4%)  |  1/50 (2%)    0/50 (0%)    0/50 (0%)    2/50 (4%)  |
|ADJUSTED (b)           |  15.4%        36.0%        24.8%        14.3%      |   3.7%         0.0%         0.0%         6.3%      |
|TERMINAL (d)           |  1/12 (8%)    4/15 (27%)   2/11 (18%)   1/10 (10%) |  1/27 (4%)    0/24 (0%)    0/24 (0%)    2/32 (6%)  |
|FIRST INCIDENCE (DAYS) |   729          674          578          652       |   734 (T)      ---          ---          734 (T)   |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.525N     P=0.127      P=0.289      P=0.606    |  P=0.301      P=0.523N     P=0.523N     P=0.560    |
|INCIDENTAL TUMOR       |  P=0.494N     P=0.086      P=0.258      P=0.601    |  P=0.301      P=0.523N     P=0.523N     P=0.560    |
|LOGISTIC REGRESSION    |  P=0.499N     P=0.094      P=0.267      P=0.598    |  P=0.301      P=0.523N     P=0.523N     P=0.560    |
|COCHRAN-ARMITAGE       |  P=0.341N                                          |  P=0.246                                           |
|FISHER EXACT           |               P=0.080      P=0.339      P=0.691N   |               P=0.500N     P=0.500N     P=0.500    |
|=================================================================================================================================|
|                                                                                                                                 |
|Skin                                                                                                                             |
|     Fibroma                                                                                                                     |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  3/50 (6%)    1/50 (2%)    1/50 (2%)    4/50 (8%)  |  0/50 (0%)    0/50 (0%)    1/50 (2%)    2/50 (4%)  |
|ADJUSTED (b)           |  19.9%         5.9%         4.0%        26.5%      |   0.0%         0.0%         4.2%         6.3%      |
|TERMINAL (d)           |  2/12 (17%)   0/15 (0%)    0/11 (0%)    1/10 (10%) |  0/27 (0%)    0/24 (0%)    1/24 (4%)    2/32 (6%)  |
|FIRST INCIDENCE (DAYS) |   678          716          636          650       |   ---          ---          734 (T)      734 (T)   |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.192      P=0.255N     P=0.369N     P=0.355    |  P=0.102        (e)        P=0.477      P=0.276    |
|INCIDENTAL TUMOR       |  P=0.206      P=0.297N     P=0.358N     P=0.356    |  P=0.102        (e)        P=0.477      P=0.276    |
|LOGISTIC REGRESSION    |  P=0.205      P=0.270N     P=0.355N     P=0.369    |  P=0.102        (e)        P=0.477      P=0.276    |
|COCHRAN-ARMITAGE       |  P=0.302                                           |  P=0.070                                           |
|FISHER EXACT           |               P=0.309N     P=0.309N     P=0.500    |                 (e)        P=0.500      P=0.247    |
|=================================================================================================================================|
         DATE: 08/06/96                     EXPERIMENT: 60968 TEST: 01                                                 PAGE  14
                            STATISTICAL ANALYSIS OF PRIMARY TUMORS IN RATS(FISCHER344) -- ISOBUTYRALDEHYDE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      500 PPM      1000 PPM     2000 PPM  |   CONTROL      500 PPM      1000 PPM     2000 PPM  |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Skin                                                                                                                             |
|     Fibroma, Fibrosarcoma, Sarcoma, Myxoma, Myxosarcoma, or Fibrous Histiocytoma                                                |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  3/50 (6%)    2/50 (4%)    2/50 (4%)    4/50 (8%)  |  0/50 (0%)    1/50 (2%)    1/50 (2%)    2/50 (4%)  |
|ADJUSTED (b)           |  19.9%         9.1%         6.5%        26.5%      |   0.0%         2.0%         4.2%         6.3%      |
|TERMINAL (d)           |  2/12 (17%)   0/15 (0%)    0/11 (0%)    1/10 (10%) |  0/27 (0%)    0/24 (0%)    1/24 (4%)    2/32 (6%)  |
|FIRST INCIDENCE (DAYS) |   678          664          541          650       |   ---          511          734 (T)      734 (T)   |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.227      P=0.440N     P=0.574N     P=0.355    |  P=0.196      P=0.521      P=0.477      P=0.276    |
|INCIDENTAL TUMOR       |  P=0.282      P=0.509N     P=0.471N     P=0.356    |  P=0.189      P=0.398      P=0.477      P=0.276    |
|LOGISTIC REGRESSION    |  P=0.280      P=0.466N     P=0.533N     P=0.369    |  P=0.151      P=0.478      P=0.477      P=0.276    |
|COCHRAN-ARMITAGE       |  P=0.357                                           |  P=0.153                                           |
|FISHER EXACT           |               P=0.500N     P=0.500N     P=0.500    |               P=0.500      P=0.500      P=0.247    |
|=================================================================================================================================|
|                                                                                                                                 |
|Skin                                                                                                                             |
|     Keratoacanthoma                                                                                                             |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  2/50 (4%)    4/50 (8%)    3/50 (6%)    2/50 (4%)  |  1/50 (2%)    0/50 (0%)    0/50 (0%)    1/50 (2%)  |
|ADJUSTED (b)           |  15.4%        21.3%        20.6%        14.3%      |   3.7%         0.0%         0.0%         3.1%      |
|TERMINAL (d)           |  1/12 (8%)    2/15 (13%)   2/11 (18%)   1/10 (10%) |  1/27 (4%)    0/24 (0%)    0/24 (0%)    1/32 (3%)  |
|FIRST INCIDENCE (DAYS) |   729          679          578          652       |   734 (T)      ---          ---          734 (T)   |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.546      P=0.419      P=0.448      P=0.606    |  P=0.632      P=0.523N     P=0.523N     P=0.724N   |
|INCIDENTAL TUMOR       |  P=0.563      P=0.345      P=0.439      P=0.601    |  P=0.632      P=0.523N     P=0.523N     P=0.724N   |
|LOGISTIC REGRESSION    |  P=0.556      P=0.380      P=0.430      P=0.598    |  P=0.632      P=0.523N     P=0.523N     P=0.724N   |
|COCHRAN-ARMITAGE       |  P=0.479N                                          |  P=0.595                                           |
|FISHER EXACT           |               P=0.339      P=0.500      P=0.691N   |               P=0.500N     P=0.500N     P=0.753N   |
|=================================================================================================================================|
         DATE: 08/06/96                     EXPERIMENT: 60968 TEST: 01                                                 PAGE  15
                            STATISTICAL ANALYSIS OF PRIMARY TUMORS IN RATS(FISCHER344) -- ISOBUTYRALDEHYDE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      500 PPM      1000 PPM     2000 PPM  |   CONTROL      500 PPM      1000 PPM     2000 PPM  |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Skin                                                                                                                             |
|     Squamous Cell Papilloma                                                                                                     |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  0/50 (0%)    2/50 (4%)    0/50 (0%)    0/50 (0%)  |  0/50 (0%)    0/50 (0%)    0/50 (0%)    0/50 (0%)  |
|ADJUSTED (b)           |   0.0%        10.3%         0.0%         0.0%      |   0.0%         0.0%         0.0%         0.0%      |
|TERMINAL (d)           |  0/12 (0%)    1/15 (7%)    0/11 (0%)    0/10 (0%)  |  0/27 (0%)    0/24 (0%)    0/24 (0%)    0/32 (0%)  |
|FIRST INCIDENCE (DAYS) |   ---          674          ---          ---       |   ---          ---          ---          ---       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.484N     P=0.264        (e)          (e)      |    (e)          (e)          (e)          (e)      |
|INCIDENTAL TUMOR       |  P=0.466N     P=0.243        (e)          (e)      |    (e)          (e)          (e)          (e)      |
|LOGISTIC REGRESSION    |  P=0.459N     P=0.253        (e)          (e)      |    (e)          (e)          (e)          (e)      |
|COCHRAN-ARMITAGE       |  P=0.405N                                          |    (e)                                             |
|FISHER EXACT           |               P=0.247        (e)          (e)      |                 (e)          (e)          (e)      |
|=================================================================================================================================|
|                                                                                                                                 |
|Skin                                                                                                                             |
|     Squamous Cell Papilloma, Papilloma, Squamous Cell Carcinoma or Keratoacanthoma                                              |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  2/50 (4%)    6/50 (12%)   3/50 (6%)    2/50 (4%)  |  1/50 (2%)    0/50 (0%)    0/50 (0%)    1/50 (2%)  |
|ADJUSTED (b)           |  15.4%        30.2%        20.6%        14.3%      |   3.7%         0.0%         0.0%         3.1%      |
|TERMINAL (d)           |  1/12 (8%)    3/15 (20%)   2/11 (18%)   1/10 (10%) |  1/27 (4%)    0/24 (0%)    0/24 (0%)    1/32 (3%)  |
|FIRST INCIDENCE (DAYS) |   729          674          578          652       |   734 (T)      ---          ---          734 (T)   |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.532N     P=0.192      P=0.448      P=0.606    |  P=0.632      P=0.523N     P=0.523N     P=0.724N   |
|INCIDENTAL TUMOR       |  P=0.507N     P=0.136      P=0.439      P=0.601    |  P=0.632      P=0.523N     P=0.523N     P=0.724N   |
|LOGISTIC REGRESSION    |  P=0.513N     P=0.155      P=0.430      P=0.598    |  P=0.632      P=0.523N     P=0.523N     P=0.724N   |
|COCHRAN-ARMITAGE       |  P=0.367N                                          |  P=0.595                                           |
|FISHER EXACT           |               P=0.134      P=0.500      P=0.691N   |               P=0.500N     P=0.500N     P=0.753N   |
|=================================================================================================================================|
         DATE: 08/06/96                     EXPERIMENT: 60968 TEST: 01                                                 PAGE  16
                            STATISTICAL ANALYSIS OF PRIMARY TUMORS IN RATS(FISCHER344) -- ISOBUTYRALDEHYDE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      500 PPM      1000 PPM     2000 PPM  |   CONTROL      500 PPM      1000 PPM     2000 PPM  |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Skin                                                                                                                             |
|     Squamous Cell Papilloma, Papilloma, or Keratoacanthoma                                                                      |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  2/50 (4%)    6/50 (12%)   3/50 (6%)    2/50 (4%)  |  1/50 (2%)    0/50 (0%)    0/50 (0%)    1/50 (2%)  |
|ADJUSTED (b)           |  15.4%        30.2%        20.6%        14.3%      |   3.7%         0.0%         0.0%         3.1%      |
|TERMINAL (d)           |  1/12 (8%)    3/15 (20%)   2/11 (18%)   1/10 (10%) |  1/27 (4%)    0/24 (0%)    0/24 (0%)    1/32 (3%)  |
|FIRST INCIDENCE (DAYS) |   729          674          578          652       |   734 (T)      ---          ---          734 (T)   |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.532N     P=0.192      P=0.448      P=0.606    |  P=0.632      P=0.523N     P=0.523N     P=0.724N   |
|INCIDENTAL TUMOR       |  P=0.507N     P=0.136      P=0.439      P=0.601    |  P=0.632      P=0.523N     P=0.523N     P=0.724N   |
|LOGISTIC REGRESSION    |  P=0.513N     P=0.155      P=0.430      P=0.598    |  P=0.632      P=0.523N     P=0.523N     P=0.724N   |
|COCHRAN-ARMITAGE       |  P=0.367N                                          |  P=0.595                                           |
|FISHER EXACT           |               P=0.134      P=0.500      P=0.691N   |               P=0.500N     P=0.500N     P=0.753N   |
|=================================================================================================================================|
|                                                                                                                                 |
|Skin: Sebaceous Gland                                                                                                            |
|     Adenoma                                                                                                                     |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  1/50 (2%)    0/50 (0%)    0/50 (0%)    0/50 (0%)  |  0/50 (0%)    0/50 (0%)    0/50 (0%)    2/50 (4%)  |
|ADJUSTED (b)           |   8.3%         0.0%         0.0%         0.0%      |   0.0%         0.0%         0.0%         6.3%      |
|TERMINAL (d)           |  1/12 (8%)    0/15 (0%)    0/11 (0%)    0/10 (0%)  |  0/27 (0%)    0/24 (0%)    0/24 (0%)    2/32 (6%)  |
|FIRST INCIDENCE (DAYS) |   733 (T)      ---          ---          ---       |   ---          ---          ---          734 (T)   |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.334N     P=0.455N     P=0.517N     P=0.536N   |  P=0.068        (e)          (e)        P=0.276    |
|INCIDENTAL TUMOR       |  P=0.334N     P=0.455N     P=0.517N     P=0.536N   |  P=0.068        (e)          (e)        P=0.276    |
|LOGISTIC REGRESSION    |  P=0.334N     P=0.455N     P=0.517N     P=0.536N   |  P=0.068        (e)          (e)        P=0.276    |
|COCHRAN-ARMITAGE       |  P=0.306N                                          |  P=0.046 *                                         |
|FISHER EXACT           |               P=0.500N     P=0.500N     P=0.500N   |                 (e)          (e)        P=0.247    |
|=================================================================================================================================|
         DATE: 08/06/96                     EXPERIMENT: 60968 TEST: 01                                                 PAGE  17
                            STATISTICAL ANALYSIS OF PRIMARY TUMORS IN RATS(FISCHER344) -- ISOBUTYRALDEHYDE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      500 PPM      1000 PPM     2000 PPM  |   CONTROL      500 PPM      1000 PPM     2000 PPM  |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Skin: Sebaceous Gland                                                                                                            |
|     Carcinoma or Adenoma                                                                                                        |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  1/50 (2%)    0/50 (0%)    0/50 (0%)    0/50 (0%)  |  1/50 (2%)    0/50 (0%)    0/50 (0%)    2/50 (4%)  |
|ADJUSTED (b)           |   8.3%         0.0%         0.0%         0.0%      |   2.4%         0.0%         0.0%         6.3%      |
|TERMINAL (d)           |  1/12 (8%)    0/15 (0%)    0/11 (0%)    0/10 (0%)  |  0/27 (0%)    0/24 (0%)    0/24 (0%)    2/32 (6%)  |
|FIRST INCIDENCE (DAYS) |   733 (T)      ---          ---          ---       |   580          ---          ---          734 (T)   |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.334N     P=0.455N     P=0.517N     P=0.536N   |  P=0.290      P=0.491N     P=0.473N     P=0.550    |
|INCIDENTAL TUMOR       |  P=0.334N     P=0.455N     P=0.517N     P=0.536N   |  P=0.246      P=0.479N     P=0.617N     P=0.493    |
|LOGISTIC REGRESSION    |  P=0.334N     P=0.455N     P=0.517N     P=0.536N   |  P=0.247      P=0.514N     P=0.572N     P=0.508    |
|COCHRAN-ARMITAGE       |  P=0.306N                                          |  P=0.246                                           |
|FISHER EXACT           |               P=0.500N     P=0.500N     P=0.500N   |               P=0.500N     P=0.500N     P=0.500    |
|=================================================================================================================================|
|                                                                                                                                 |
|Testes                                                                                                                           |
|     Adenoma                                                                                                                     |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            | 30/50 (60%)  43/50 (86%)  30/50 (60%)  36/50 (72%) |                                                    |
|ADJUSTED (b)           |  88.9%       100.0%       100.0%        94.0%      |                                                    |
|TERMINAL (d)           |  9/12 (75%)  15/15 (100%) 11/11 (100%)  8/10 (80%) |                                                    |
|FIRST INCIDENCE (DAYS) |   421          540          440          441       |                                                    |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.064      P=0.145      P=0.353      P=0.060    |                                                    |
|INCIDENTAL TUMOR       |  P=0.213      P=0.005 **   P=0.490      P=0.125    |                                                    |
|LOGISTIC REGRESSION    |  P=0.219      P=0.004 **   P=0.444      P=0.108    |                                                    |
|COCHRAN-ARMITAGE       |  P=0.388                                           |                                                    |
|FISHER EXACT           |               P=0.003 **   P=0.581N     P=0.146    |                                                    |
|=================================================================================================================================|
         DATE: 08/06/96                     EXPERIMENT: 60968 TEST: 01                                                 PAGE  18
                            STATISTICAL ANALYSIS OF PRIMARY TUMORS IN RATS(FISCHER344) -- ISOBUTYRALDEHYDE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      500 PPM      1000 PPM     2000 PPM  |   CONTROL      500 PPM      1000 PPM     2000 PPM  |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Thymus                                                                                                                           |
|     Thymoma Malignant                                                                                                           |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  0/50 (0%)    0/49 (0%)    2/50 (4%)    0/49 (0%)  |  0/48 (0%)    0/50 (0%)    0/50 (0%)    0/50 (0%)  |
|ADJUSTED (b)           |   0.0%         0.0%        12.1%         0.0%      |   0.0%         0.0%         0.0%         0.0%      |
|TERMINAL (d)           |  0/12 (0%)    0/15 (0%)    1/11 (9%)    0/10 (0%)  |  0/26 (0%)    0/24 (0%)    0/24 (0%)    0/32 (0%)  |
|FIRST INCIDENCE (DAYS) |   ---          ---          601          ---       |   ---          ---          ---          ---       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.551        (e)        P=0.208        (e)      |    (e)          (e)          (e)          (e)      |
|INCIDENTAL TUMOR       |  P=0.580        (e)        P=0.230        (e)      |    (e)          (e)          (e)          (e)      |
|LOGISTIC REGRESSION    |  P=0.572        (e)        P=0.219        (e)      |    (e)          (e)          (e)          (e)      |
|COCHRAN-ARMITAGE       |  P=0.592                                           |    (e)                                             |
|FISHER EXACT           |                 (e)        P=0.247        (e)      |                 (e)          (e)          (e)      |
|=================================================================================================================================|
|                                                                                                                                 |
|Thymus                                                                                                                           |
|     Thymoma: Benign, Malignant, NOS                                                                                             |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  0/50 (0%)    0/49 (0%)    3/50 (6%)    0/49 (0%)  |  0/48 (0%)    0/50 (0%)    0/50 (0%)    0/50 (0%)  |
|ADJUSTED (b)           |   0.0%         0.0%        20.9%         0.0%      |   0.0%         0.0%         0.0%         0.0%      |
|TERMINAL (d)           |  0/12 (0%)    0/15 (0%)    2/11 (18%)   0/10 (0%)  |  0/26 (0%)    0/24 (0%)    0/24 (0%)    0/32 (0%)  |
|FIRST INCIDENCE (DAYS) |   ---          ---          601          ---       |   ---          ---          ---          ---       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.478        (e)        P=0.099        (e)      |    (e)          (e)          (e)          (e)      |
|INCIDENTAL TUMOR       |  P=0.504        (e)        P=0.110        (e)      |    (e)          (e)          (e)          (e)      |
|LOGISTIC REGRESSION    |  P=0.485        (e)        P=0.097        (e)      |    (e)          (e)          (e)          (e)      |
|COCHRAN-ARMITAGE       |  P=0.536                                           |    (e)                                             |
|FISHER EXACT           |                 (e)        P=0.121        (e)      |                 (e)          (e)          (e)      |
|=================================================================================================================================|
         DATE: 08/06/96                     EXPERIMENT: 60968 TEST: 01                                                 PAGE  19
                            STATISTICAL ANALYSIS OF PRIMARY TUMORS IN RATS(FISCHER344) -- ISOBUTYRALDEHYDE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      500 PPM      1000 PPM     2000 PPM  |   CONTROL      500 PPM      1000 PPM     2000 PPM  |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Thyroid Gland: C-Cell                                                                                                            |
|     Adenoma                                                                                                                     |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  1/50 (2%)    2/49 (4%)    4/50 (8%)    2/50 (4%)  |  1/49 (2%)    4/49 (8%)    2/50 (4%)    3/50 (6%)  |
|ADJUSTED (b)           |   5.6%        11.3%        22.2%        20.0%      |   3.7%        14.6%         8.3%         9.4%      |
|TERMINAL (d)           |  0/12 (0%)    1/15 (7%)    1/11 (9%)    2/10 (20%) |  1/27 (4%)    3/24 (13%)   2/24 (8%)    3/32 (9%)  |
|FIRST INCIDENCE (DAYS) |   698          692          617          733 (T)   |   734 (T)      624          734 (T)      734 (T)   |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.247      P=0.532      P=0.150      P=0.411    |  P=0.472      P=0.159      P=0.459      P=0.367    |
|INCIDENTAL TUMOR       |  P=0.282      P=0.483      P=0.111      P=0.420    |  P=0.441      P=0.152      P=0.459      P=0.367    |
|LOGISTIC REGRESSION    |  P=0.273      P=0.526      P=0.143      P=0.397    |  P=0.430      P=0.186      P=0.459      P=0.367    |
|COCHRAN-ARMITAGE       |  P=0.390                                           |  P=0.382                                           |
|FISHER EXACT           |               P=0.492      P=0.181      P=0.500    |               P=0.181      P=0.508      P=0.316    |
|=================================================================================================================================|
|                                                                                                                                 |
|Thyroid Gland: C-Cell                                                                                                            |
|     Carcinoma                                                                                                                   |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  3/50 (6%)    1/49 (2%)    1/50 (2%)    1/50 (2%)  |  1/49 (2%)    0/49 (0%)    0/50 (0%)    0/50 (0%)  |
|ADJUSTED (b)           |  19.0%         3.6%         2.4%         7.1%      |   3.7%         0.0%         0.0%         0.0%      |
|TERMINAL (d)           |  2/12 (17%)   0/15 (0%)    0/11 (0%)    0/10 (0%)  |  1/27 (4%)    0/24 (0%)    0/24 (0%)    0/32 (0%)  |
|FIRST INCIDENCE (DAYS) |   608          667          520          680       |   734 (T)      ---          ---          ---       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.331N     P=0.255N     P=0.351N     P=0.396N   |  P=0.288N     P=0.523N     P=0.523N     P=0.466N   |
|INCIDENTAL TUMOR       |  P=0.247N     P=0.277N     P=0.240N     P=0.351N   |  P=0.288N     P=0.523N     P=0.523N     P=0.466N   |
|LOGISTIC REGRESSION    |  P=0.257N     P=0.291N     P=0.317N     P=0.366N   |  P=0.288N     P=0.523N     P=0.523N     P=0.466N   |
|COCHRAN-ARMITAGE       |  P=0.240N                                          |  P=0.303N                                          |
|FISHER EXACT           |               P=0.316N     P=0.309N     P=0.309N   |               P=0.500N     P=0.495N     P=0.495N   |
|=================================================================================================================================|
         DATE: 08/06/96                     EXPERIMENT: 60968 TEST: 01                                                 PAGE  20
                            STATISTICAL ANALYSIS OF PRIMARY TUMORS IN RATS(FISCHER344) -- ISOBUTYRALDEHYDE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      500 PPM      1000 PPM     2000 PPM  |   CONTROL      500 PPM      1000 PPM     2000 PPM  |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Thyroid Gland: C-Cell                                                                                                            |
|     Carcinoma or Adenoma                                                                                                        |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  4/50 (8%)    3/49 (6%)    5/50 (10%)   3/50 (6%)  |  2/49 (4%)    4/49 (8%)    2/50 (4%)    3/50 (6%)  |
|ADJUSTED (b)           |  23.5%        14.5%        24.0%        25.7%      |   7.4%        14.6%         8.3%         9.4%      |
|TERMINAL (d)           |  2/12 (17%)   1/15 (7%)    1/11 (9%)    2/10 (20%) |  2/27 (7%)    3/24 (13%)   2/24 (8%)    3/32 (9%)  |
|FIRST INCIDENCE (DAYS) |   608          667          520          680       |   734 (T)      624          734 (T)      734 (T)   |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.476      P=0.433N     P=0.425      P=0.635N   |  P=0.537N     P=0.301      P=0.654      P=0.578    |
|INCIDENTAL TUMOR       |  P=0.571      P=0.485N     P=0.460      P=0.593N   |  P=0.567N     P=0.292      P=0.654      P=0.578    |
|LOGISTIC REGRESSION    |  P=0.564      P=0.472N     P=0.448      P=0.629N   |  P=0.581N     P=0.344      P=0.654      P=0.578    |
|COCHRAN-ARMITAGE       |  P=0.478N                                          |  P=0.532                                           |
|FISHER EXACT           |               P=0.511N     P=0.500      P=0.500N   |               P=0.339      P=0.684N     P=0.510    |
|=================================================================================================================================|
|                                                                                                                                 |
|Thyroid Gland: Follicular Cell                                                                                                   |
|     Carcinoma                                                                                                                   |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  0/50 (0%)    0/49 (0%)    2/50 (4%)    0/50 (0%)  |  1/49 (2%)    0/49 (0%)    0/50 (0%)    0/50 (0%)  |
|ADJUSTED (b)           |   0.0%         0.0%         5.9%         0.0%      |   3.7%         0.0%         0.0%         0.0%      |
|TERMINAL (d)           |  0/12 (0%)    0/15 (0%)    0/11 (0%)    0/10 (0%)  |  1/27 (4%)    0/24 (0%)    0/24 (0%)    0/32 (0%)  |
|FIRST INCIDENCE (DAYS) |   ---          ---          576          ---       |   734 (T)      ---          ---          ---       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.574        (e)        P=0.212        (e)      |  P=0.288N     P=0.523N     P=0.523N     P=0.466N   |
|INCIDENTAL TUMOR       |  P=0.629        (e)        P=0.236        (e)      |  P=0.288N     P=0.523N     P=0.523N     P=0.466N   |
|LOGISTIC REGRESSION    |  P=0.605        (e)        P=0.248        (e)      |  P=0.288N     P=0.523N     P=0.523N     P=0.466N   |
|COCHRAN-ARMITAGE       |  P=0.596                                           |  P=0.303N                                          |
|FISHER EXACT           |                 (e)        P=0.247        (e)      |               P=0.500N     P=0.495N     P=0.495N   |
|=================================================================================================================================|
         DATE: 08/06/96                     EXPERIMENT: 60968 TEST: 01                                                 PAGE  21
                            STATISTICAL ANALYSIS OF PRIMARY TUMORS IN RATS(FISCHER344) -- ISOBUTYRALDEHYDE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      500 PPM      1000 PPM     2000 PPM  |   CONTROL      500 PPM      1000 PPM     2000 PPM  |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Thyroid Gland: Follicular Cell                                                                                                   |
|     Carcinoma or Adenoma                                                                                                        |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  0/50 (0%)    0/49 (0%)    2/50 (4%)    0/50 (0%)  |  1/49 (2%)    0/49 (0%)    1/50 (2%)    0/50 (0%)  |
|ADJUSTED (b)           |   0.0%         0.0%         5.9%         0.0%      |   3.7%         0.0%         2.6%         0.0%      |
|TERMINAL (d)           |  0/12 (0%)    0/15 (0%)    0/11 (0%)    0/10 (0%)  |  1/27 (4%)    0/24 (0%)    0/24 (0%)    0/32 (0%)  |
|FIRST INCIDENCE (DAYS) |   ---          ---          576          ---       |   734 (T)      ---          681          ---       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.574        (e)        P=0.212        (e)      |  P=0.381N     P=0.523N     P=0.758N     P=0.466N   |
|INCIDENTAL TUMOR       |  P=0.629        (e)        P=0.236        (e)      |  P=0.373N     P=0.523N     P=0.678N     P=0.466N   |
|LOGISTIC REGRESSION    |  P=0.605        (e)        P=0.248        (e)      |  P=0.385N     P=0.523N     P=0.741N     P=0.466N   |
|COCHRAN-ARMITAGE       |  P=0.596                                           |  P=0.400N                                          |
|FISHER EXACT           |                 (e)        P=0.247        (e)      |               P=0.500N     P=0.747N     P=0.495N   |
|=================================================================================================================================|
|                                                                                                                                 |
|Uterus                                                                                                                           |
|     Polyp Stromal                                                                                                               |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |                                                    |  2/50 (4%)    5/50 (10%)   1/50 (2%)    6/50 (12%) |
|ADJUSTED (b)           |                                                    |   6.5%        18.6%         4.2%        16.3%      |
|TERMINAL (d)           |                                                    |  1/27 (4%)    4/24 (17%)   1/24 (4%)    4/32 (13%) |
|FIRST INCIDENCE (DAYS) |                                                    |   679          575          734 (T)      549       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |                                                    |  P=0.229      P=0.188      P=0.514N     P=0.189    |
|INCIDENTAL TUMOR       |                                                    |  P=0.170      P=0.212      P=0.437N     P=0.137    |
|LOGISTIC REGRESSION    |                                                    |  P=0.170      P=0.225      P=0.472N     P=0.146    |
|COCHRAN-ARMITAGE       |                                                    |  P=0.151                                           |
|FISHER EXACT           |                                                    |               P=0.218      P=0.500N     P=0.134    |
|=================================================================================================================================|
         DATE: 08/06/96                     EXPERIMENT: 60968 TEST: 01                                                 PAGE  22
                            STATISTICAL ANALYSIS OF PRIMARY TUMORS IN RATS(FISCHER344) -- ISOBUTYRALDEHYDE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      500 PPM      1000 PPM     2000 PPM  |   CONTROL      500 PPM      1000 PPM     2000 PPM  |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Uterus                                                                                                                           |
|     Sarcoma Stromal                                                                                                             |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |                                                    |  0/50 (0%)    2/50 (4%)    0/50 (0%)    1/50 (2%)  |
|ADJUSTED (b)           |                                                    |   0.0%         7.1%         0.0%         2.0%      |
|TERMINAL (d)           |                                                    |  0/27 (0%)    1/24 (4%)    0/24 (0%)    0/32 (0%)  |
|FIRST INCIDENCE (DAYS) |                                                    |   ---          681          ---          441       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |                                                    |  P=0.565      P=0.227        (e)        P=0.512    |
|INCIDENTAL TUMOR       |                                                    |  P=0.543      P=0.270        (e)        P=0.455    |
|LOGISTIC REGRESSION    |                                                    |  P=0.486      P=0.242        (e)        P=0.325    |
|COCHRAN-ARMITAGE       |                                                    |  P=0.539                                           |
|FISHER EXACT           |                                                    |               P=0.247        (e)        P=0.500    |
|=================================================================================================================================|
|                                                                                                                                 |
|Uterus                                                                                                                           |
|     Sarcoma Stromal or Polyp Stromal                                                                                            |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |                                                    |  2/50 (4%)    6/50 (12%)   1/50 (2%)    7/50 (14%) |
|ADJUSTED (b)           |                                                    |   6.5%        21.0%         4.2%        18.0%      |
|TERMINAL (d)           |                                                    |  1/27 (4%)    4/24 (17%)   1/24 (4%)    4/32 (13%) |
|FIRST INCIDENCE (DAYS) |                                                    |   679          575          734 (T)      441       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |                                                    |  P=0.174      P=0.117      P=0.514N     P=0.123    |
|INCIDENTAL TUMOR       |                                                    |  P=0.121      P=0.148      P=0.437N     P=0.079    |
|LOGISTIC REGRESSION    |                                                    |  P=0.110      P=0.141      P=0.472N     P=0.071    |
|COCHRAN-ARMITAGE       |                                                    |  P=0.109                                           |
|FISHER EXACT           |                                                    |               P=0.134      P=0.500N     P=0.080    |
|=================================================================================================================================|
         DATE: 08/06/96                     EXPERIMENT: 60968 TEST: 01                                                 PAGE  23
                            STATISTICAL ANALYSIS OF PRIMARY TUMORS IN RATS(FISCHER344) -- ISOBUTYRALDEHYDE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      500 PPM      1000 PPM     2000 PPM  |   CONTROL      500 PPM      1000 PPM     2000 PPM  |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|All Organs                                                                                                                       |
|     Leukemia: Lymphocytic, Monocytic, Mononuclear, or Undifferentiated                                                          |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            | 33/50 (66%)  32/50 (64%)  23/50 (46%)  34/50 (68%) | 12/50 (24%)  19/50 (38%)  18/50 (36%)  25/50 (50%) |
|ADJUSTED (b)           |  84.9%        85.1%        77.5%        91.0%      |  28.7%        54.0%        46.5%        57.4%      |
|TERMINAL (d)           |  7/12 (58%)  10/15 (67%)   6/11 (55%)   7/10 (70%) |  2/27 (7%)    9/24 (38%)   6/24 (25%)  14/32 (44%) |
|FIRST INCIDENCE (DAYS) |   259          554          468          441       |   428          608          580          541       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.133      P=0.309N     P=0.233N     P=0.164    |  P=0.065      P=0.116      P=0.201      P=0.047 *  |
|INCIDENTAL TUMOR       |  P=0.300      P=0.407N     P=0.114N     P=0.285    |  P=0.004 **   P=0.121      P=0.156      P=0.003 ** |
|LOGISTIC REGRESSION    |  P=0.406      P=0.459N     P=0.046N*    P=0.428    |  P=0.008 **   P=0.094      P=0.087      P=0.005 ** |
|COCHRAN-ARMITAGE       |  P=0.520                                           |  P=0.008 **                                        |
|FISHER EXACT           |               P=0.500N     P=0.035N*    P=0.500    |               P=0.097      P=0.138      P=0.006 ** |
|=================================================================================================================================|
|                                                                                                                                 |
|All Organs                                                                                                                       |
|     Malignant Lymphoma: Histiocytic, Lymphocytic, Mixed, NOS, or Undifferentiated                                               |
|     Cell Type                                                                                                                   |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  1/50 (2%)    1/50 (2%)    0/50 (0%)    0/50 (0%)  |  0/50 (0%)    0/50 (0%)    2/50 (4%)    0/50 (0%)  |
|ADJUSTED (b)           |   2.3%         3.3%         0.0%         0.0%      |   0.0%         0.0%         6.3%         0.0%      |
|TERMINAL (d)           |  0/12 (0%)    0/15 (0%)    0/11 (0%)    0/10 (0%)  |  0/27 (0%)    0/24 (0%)    1/24 (4%)    0/32 (0%)  |
|FIRST INCIDENCE (DAYS) |   549          663          ---          ---       |   ---          ---          608          ---       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.286N     P=0.749N     P=0.530N     P=0.514N   |  P=0.625        (e)        P=0.244        (e)      |
|INCIDENTAL TUMOR       |  P=0.253N     P=0.756      P=0.500N     P=0.461N   |  P=0.563        (e)        P=0.166        (e)      |
|LOGISTIC REGRESSION    |  P=0.229N     P=0.759      P=0.496N     P=0.504N   |  P=0.591        (e)        P=0.230        (e)      |
|COCHRAN-ARMITAGE       |  P=0.236N                                          |  P=0.595                                           |
|FISHER EXACT           |               P=0.753N     P=0.500N     P=0.500N   |                 (e)        P=0.247        (e)      |
|=================================================================================================================================|
         DATE: 08/06/96                     EXPERIMENT: 60968 TEST: 01                                                 PAGE  24
                            STATISTICAL ANALYSIS OF PRIMARY TUMORS IN RATS(FISCHER344) -- ISOBUTYRALDEHYDE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      500 PPM      1000 PPM     2000 PPM  |   CONTROL      500 PPM      1000 PPM     2000 PPM  |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|All Organs                                                                                                                       |
|     Mesothelioma: Benign, Malignant, NOS                                                                                        |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  2/50 (4%)    0/50 (0%)    1/50 (2%)    2/50 (4%)  |  0/50 (0%)    0/50 (0%)    0/50 (0%)    0/50 (0%)  |
|ADJUSTED (b)           |   8.1%         0.0%         5.3%        11.9%      |   0.0%         0.0%         0.0%         0.0%      |
|TERMINAL (d)           |  0/12 (0%)    0/15 (0%)    0/11 (0%)    1/10 (10%) |  0/27 (0%)    0/24 (0%)    0/24 (0%)    0/32 (0%)  |
|FIRST INCIDENCE (DAYS) |   604          ---          686          463       |   ---          ---          ---          ---       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.378      P=0.225N     P=0.546N     P=0.631    |    (e)          (e)          (e)          (e)      |
|INCIDENTAL TUMOR       |  P=0.476      P=0.244N     P=0.594N     P=0.662N   |    (e)          (e)          (e)          (e)      |
|LOGISTIC REGRESSION    |  P=0.468      P=0.236N     P=0.524N     P=0.691N   |    (e)          (e)          (e)          (e)      |
|COCHRAN-ARMITAGE       |  P=0.469                                           |    (e)                                             |
|FISHER EXACT           |               P=0.247N     P=0.500N     P=0.691N   |                 (e)          (e)          (e)      |
|=================================================================================================================================|
|                                                                                                                                 |
|All Organs                                                                                                                       |
|     Benign Tumors                                                                                                               |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            | 47/50 (94%)  49/50 (98%)  46/50 (92%)  49/50 (98%) | 44/50 (88%)  37/50 (74%)  44/50 (88%)  41/50 (82%) |
|ADJUSTED (b)           | 100.0%       100.0%       100.0%       100.0%      |  97.8%        89.4%        97.7%        97.6%      |
|TERMINAL (d)           | 12/12 (100%) 15/15 (100%) 11/11 (100%) 10/10 (100%)| 26/27 (96%)  20/24 (83%)  23/24 (96%)  31/32 (97%) |
|FIRST INCIDENCE (DAYS) |   421          384          440          441       |   400          511          487          511       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.060      P=0.392N     P=0.318      P=0.110    |  P=0.103N     P=0.269N     P=0.479      P=0.070N   |
|INCIDENTAL TUMOR       |  P=0.336      P=0.318      P=0.606N     P=0.378    |  P=0.221N     P=0.077N     P=0.330N     P=0.064N   |
|LOGISTIC REGRESSION    |  P=0.408      P=0.245      P=0.543N     P=0.364    |  P=0.249N     P=0.034N*    P=0.279N     P=0.053N   |
|COCHRAN-ARMITAGE       |  P=0.343                                           |  P=0.475N                                          |
|FISHER EXACT           |               P=0.309      P=0.500N     P=0.309    |               P=0.062N     P=0.620N     P=0.288N   |
|=================================================================================================================================|
         DATE: 08/06/96                     EXPERIMENT: 60968 TEST: 01                                                 PAGE  25
                            STATISTICAL ANALYSIS OF PRIMARY TUMORS IN RATS(FISCHER344) -- ISOBUTYRALDEHYDE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      500 PPM      1000 PPM     2000 PPM  |   CONTROL      500 PPM      1000 PPM     2000 PPM  |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|All Organs                                                                                                                       |
|     Malignant Tumors                                                                                                            |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            | 40/50 (80%)  38/50 (76%)  33/50 (66%)  36/50 (72%) | 21/50 (42%)  30/50 (60%)  25/50 (50%)  30/50 (60%) |
|ADJUSTED (b)           |  92.5%        89.8%        86.6%        91.3%      |  50.4%        74.3%        61.8%        65.9%      |
|TERMINAL (d)           |  9/12 (75%)  11/15 (73%)   7/11 (64%)   7/10 (70%) |  8/27 (30%)  14/24 (58%)  10/24 (42%)  17/32 (53%) |
|FIRST INCIDENCE (DAYS) |   259          384          419          441       |   428          511          580          441       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.284      P=0.257N     P=0.432N     P=0.358    |  P=0.368      P=0.081      P=0.330      P=0.231    |
|INCIDENTAL TUMOR       |  P=0.238N     P=0.403N     P=0.134N     P=0.365N   |  P=0.087      P=0.070      P=0.344      P=0.037 *  |
|LOGISTIC REGRESSION    |  P=0.215N     P=0.384N     P=0.091N     P=0.267N   |  P=0.101      P=0.058      P=0.367      P=0.041 *  |
|COCHRAN-ARMITAGE       |  P=0.186N                                          |  P=0.098                                           |
|FISHER EXACT           |               P=0.405N     P=0.088N     P=0.241N   |               P=0.055      P=0.274      P=0.055    |
|=================================================================================================================================|
|                                                                                                                                 |
|All Organs                                                                                                                       |
|     Malignant and Benign Tumors                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            | 50/50 (100%) 49/50 (98%)  49/50 (98%)  50/50 (100%)| 48/50 (96%)  49/50 (98%)  50/50 (100%) 49/50 (98%) |
|ADJUSTED (b)           | 100.0%       100.0%       100.0%       100.0%      |  98.0%       100.0%       100.0%        98.0%      |
|TERMINAL (d)           | 12/12 (100%) 15/15 (100%) 11/11 (100%) 10/10 (100%)| 26/27 (96%)  24/24 (100%) 24/24 (100%) 31/32 (97%) |
|FIRST INCIDENCE (DAYS) |   259          384          419          441       |   400          511          487          441       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.080      P=0.267N     P=0.319      P=0.162    |  P=0.158N     P=0.367      P=0.395      P=0.239N   |
|INCIDENTAL TUMOR       |  P=0.686N     P=0.500N     P=0.690N       (e)      |  P=0.632N     P=0.523      P=0.523      P=0.724    |
|LOGISTIC REGRESSION    |  P=0.590N     P=0.500N     P=0.450N       (e)      |  P=0.624N     P=0.613      P=0.494      P=0.697    |
|COCHRAN-ARMITAGE       |  P=0.595                                           |  P=0.366                                           |
|FISHER EXACT           |               P=0.500N     P=0.500N     P=1.000N   |               P=0.500      P=0.247      P=0.500    |
|=================================================================================================================================|
         DATE: 08/06/96                     EXPERIMENT: 60968 TEST: 01                                                 PAGE  26
                            STATISTICAL ANALYSIS OF PRIMARY TUMORS IN RATS(FISCHER344) -- ISOBUTYRALDEHYDE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
                                                                           
 (a)  Number of tumor-bearing animals / number of animals examined at site.
 (b)  Kaplan-Meier estimated lifetime tumor incidence after adjustment for 
      intercurrent mortality.
 (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.  The incidental tumor 
      test regards these lesions as non-fatal.  Logistic regression is an alternative
      method for analyzing the incidence of non-fatal tumors.  The Cochran-Armitage
      and Fisher's 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. 
 (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).