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TDMS Study 60968-02 Pathology Tables

NTP                                        STATISTICAL ANALYSIS OF PRIMARY TUMORS                              REPORT: PEIRPT08     
LAB: Battelle Northwest                                     ISOBUTYRALDEHYDE                                   DATE: 09/23/96       
EXPERIMENT: 60968 TEST: 02                                                                                     TIME: 16:03:49       
TEST TYPE:  CHRONIC                             CAGES FROM 0000 TO LAST CAGE                                   PAGE:       1        
CONT: N01-ES-95241                              ROUTE: RESPIRATORY EXPOSURE WHOLE BODY                         NTP C#: 60968B       
PATHOLOGIST: S. GRUMBEIN                     GRUMBEIN, SONDRA                                                  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: 09/23/96       
EXPERIMENT: 60968 TEST: 02                                                                                     TIME: 16:03:49       
TEST TYPE:  CHRONIC                             CAGES FROM 0000 TO LAST CAGE                                                        
CONT: N01-ES-95241                              ROUTE: RESPIRATORY EXPOSURE WHOLE BODY                         NTP C#: 60968B       
PATHOLOGIST: S. GRUMBEIN                     GRUMBEIN, SONDRA                                                  CAS: 0078-84-2       


                                                    MICE(B6C3F1)
                                              ----------------------------
             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
                                                    Epididymis
                                                    Gallbladder
                                                    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: 09/23/96       
EXPERIMENT: 60968 TEST: 02                                                                                     TIME: 16:03:49       
TEST TYPE:  CHRONIC                             CAGES FROM 0000 TO LAST CAGE                                                        
CONT: N01-ES-95241                              ROUTE: RESPIRATORY EXPOSURE WHOLE BODY                         NTP C#: 60968B       
PATHOLOGIST: S. GRUMBEIN                     GRUMBEIN, SONDRA                                                  CAS: 0078-84-2       


                                     SUMMARY OF STATISTICALLY SIGNIFICANT (P<=.05) RESULTS
                                        IN THE ANALYSIS OF THE STUDY OF ISOBUTYRALDEHYDE
              ====================================================================================================
                                                           MALE MICE
                                                          -------------
                  ORGAN                               MORPHOLOGY
                 -------                             ------------
              Liver                         Hepatocellular Carcinoma
                                            Hepatocellular Carcinoma or Hepatocellular Adenoma
                                            Hepatocellular Carcinoma, Hepatocellular Adenoma, or Hepatoblastoma
              All Organs                    Malignant Lymphoma: Histiocytic, Lymphocytic, Mixed, NOS, or Undifferentiated
                                             Cell Type
                                            Malignant and Benign Tumors
              ====================================================================================================
                                                           FEMALE MICE
                                                          -------------
                  ORGAN                               MORPHOLOGY
                 -------                             ------------
              Skin                          Fibroma, Fibrosarcoma, Sarcoma, Myxoma, Myxosarcoma, or Fibrous Histiocytoma
                                            Fibrosarcoma
                                            Fibrosarcoma, Sarcoma, Myxosarcoma, or Fibrous Histiocytoma
              All Organs                    Benign Tumors
              ====================================================================================================
         DATE: 09/23/96                     EXPERIMENT: 60968 TEST: 02                                                 PAGE   1
                              STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- 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)            |  2/50 (4%)    1/50 (2%)    1/50 (2%)    1/50 (2%)  |  0/50 (0%)    2/49 (4%)    0/50 (0%)    0/50 (0%)  |
|ADJUSTED (b)           |   5.0%         2.7%         2.9%         3.3%      |   0.0%         6.3%         0.0%         0.0%      |
|TERMINAL (d)           |  2/40 (5%)    1/37 (3%)    1/35 (3%)    1/30 (3%)  |  0/28 (0%)    2/32 (6%)    0/36 (0%)    0/37 (0%)  |
|FIRST INCIDENCE (DAYS) |   733 (T)      733 (T)      733 (T)      733 (T)   |   ---          735 (T)      ---          ---       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.501N     P=0.527N     P=0.547N     P=0.600N   |  P=0.352N     P=0.268        (e)          (e)      |
|INCIDENTAL TUMOR       |  P=0.501N     P=0.527N     P=0.547N     P=0.600N   |  P=0.352N     P=0.268        (e)          (e)      |
|LOGISTIC REGRESSION    |  P=0.501N     P=0.527N     P=0.547N     P=0.600N   |  P=0.352N     P=0.268        (e)          (e)      |
|COCHRAN-ARMITAGE       |  P=0.409N                                          |  P=0.404N                                          |
|FISHER EXACT           |               P=0.500N     P=0.500N     P=0.500N   |               P=0.242        (e)          (e)      |
|=================================================================================================================================|
|                                                                                                                                 |
|Adrenal Medulla                                                                                                                  |
|     Pheochromocytoma Benign                                                                                                     |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  0/50 (0%)    1/50 (2%)    0/50 (0%)    1/50 (2%)  |  1/50 (2%)    2/49 (4%)    0/50 (0%)    0/50 (0%)  |
|ADJUSTED (b)           |   0.0%         2.7%         0.0%         2.3%      |   3.6%         5.7%         0.0%         0.0%      |
|TERMINAL (d)           |  0/40 (0%)    1/37 (3%)    0/35 (0%)    0/30 (0%)  |  1/28 (4%)    1/32 (3%)    0/36 (0%)    0/37 (0%)  |
|FIRST INCIDENCE (DAYS) |   ---          733 (T)      ---          616       |   735 (T)      691          ---          ---       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.368      P=0.484        (e)        P=0.483    |  P=0.156N     P=0.537      P=0.450N     P=0.444N   |
|INCIDENTAL TUMOR       |  P=0.424      P=0.484        (e)        P=0.638    |  P=0.177N     P=0.494      P=0.450N     P=0.444N   |
|LOGISTIC REGRESSION    |  P=0.414      P=0.484        (e)        P=0.563    |  P=0.171N     P=0.521      P=0.450N     P=0.444N   |
|COCHRAN-ARMITAGE       |  P=0.405                                           |  P=0.187N                                          |
|FISHER EXACT           |               P=0.500        (e)        P=0.500    |               P=0.492      P=0.500N     P=0.500N   |
|=================================================================================================================================|
         DATE: 09/23/96                     EXPERIMENT: 60968 TEST: 02                                                 PAGE   2
                              STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- 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: Benign, Complex, Malignant, NOS                                                                           |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  0/50 (0%)    1/50 (2%)    0/50 (0%)    1/50 (2%)  |  1/50 (2%)    2/49 (4%)    0/50 (0%)    1/50 (2%)  |
|ADJUSTED (b)           |   0.0%         2.7%         0.0%         2.3%      |   3.6%         5.7%         0.0%         2.1%      |
|TERMINAL (d)           |  0/40 (0%)    1/37 (3%)    0/35 (0%)    0/30 (0%)  |  1/28 (4%)    1/32 (3%)    0/36 (0%)    0/37 (0%)  |
|FIRST INCIDENCE (DAYS) |   ---          733 (T)      ---          616       |   735 (T)      691          ---          611       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.368      P=0.484        (e)        P=0.483    |  P=0.449N     P=0.537      P=0.450N     P=0.719N   |
|INCIDENTAL TUMOR       |  P=0.424      P=0.484        (e)        P=0.638    |  P=0.548N     P=0.494      P=0.450N     P=0.637    |
|LOGISTIC REGRESSION    |  P=0.414      P=0.484        (e)        P=0.563    |  P=0.496N     P=0.521      P=0.450N     P=0.759    |
|COCHRAN-ARMITAGE       |  P=0.405                                           |  P=0.498N                                          |
|FISHER EXACT           |               P=0.500        (e)        P=0.500    |               P=0.492      P=0.500N     P=0.753N   |
|=================================================================================================================================|
|                                                                                                                                 |
|Harderian Gland                                                                                                                  |
|     Adenoma                                                                                                                     |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  1/50 (2%)    0/50 (0%)    1/50 (2%)    2/50 (4%)  |  1/50 (2%)    4/50 (8%)    1/50 (2%)    1/50 (2%)  |
|ADJUSTED (b)           |   2.5%         0.0%         2.7%         6.7%      |   3.6%        11.2%         2.8%         2.7%      |
|TERMINAL (d)           |  1/40 (3%)    0/37 (0%)    0/35 (0%)    2/30 (7%)  |  1/28 (4%)    2/32 (6%)    1/36 (3%)    1/37 (3%)  |
|FIRST INCIDENCE (DAYS) |   733 (T)      ---          711          733 (T)   |   735 (T)      686          735 (T)      735 (T)   |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.184      P=0.516N     P=0.737      P=0.400    |  P=0.300N     P=0.215      P=0.705N     P=0.699N   |
|INCIDENTAL TUMOR       |  P=0.260      P=0.516N     P=0.720      P=0.400    |  P=0.329N     P=0.165      P=0.705N     P=0.699N   |
|LOGISTIC REGRESSION    |  P=0.207      P=0.516N     P=0.737      P=0.400    |  P=0.333N     P=0.197      P=0.705N     P=0.699N   |
|COCHRAN-ARMITAGE       |  P=0.247                                           |  P=0.373N                                          |
|FISHER EXACT           |               P=0.500N     P=0.753N     P=0.500    |               P=0.181      P=0.753N     P=0.753N   |
|=================================================================================================================================|
         DATE: 09/23/96                     EXPERIMENT: 60968 TEST: 02                                                 PAGE   3
                              STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- ISOBUTYRALDEHYDE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      500 PPM      1000 PPM     2000 PPM  |   CONTROL      500 PPM      1000 PPM     2000 PPM  |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Harderian Gland                                                                                                                  |
|     Carcinoma                                                                                                                   |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  2/50 (4%)    2/50 (4%)    1/50 (2%)    0/50 (0%)  |  1/50 (2%)    0/50 (0%)    1/50 (2%)    0/50 (0%)  |
|ADJUSTED (b)           |   5.0%         4.7%         2.9%         0.0%      |   3.6%         0.0%         2.8%         0.0%      |
|TERMINAL (d)           |  2/40 (5%)    1/37 (3%)    1/35 (3%)    0/30 (0%)  |  1/28 (4%)    0/32 (0%)    1/36 (3%)    0/37 (0%)  |
|FIRST INCIDENCE (DAYS) |   733 (T)      580          733 (T)      ---       |   735 (T)      ---          735 (T)      ---       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.167N     P=0.672      P=0.547N     P=0.304N   |  P=0.352N     P=0.473N     P=0.705N     P=0.444N   |
|INCIDENTAL TUMOR       |  P=0.147N     P=0.656N     P=0.547N     P=0.304N   |  P=0.352N     P=0.473N     P=0.705N     P=0.444N   |
|LOGISTIC REGRESSION    |  P=0.129N     P=0.688N     P=0.547N     P=0.304N   |  P=0.352N     P=0.473N     P=0.705N     P=0.444N   |
|COCHRAN-ARMITAGE       |  P=0.125N                                          |  P=0.405N                                          |
|FISHER EXACT           |               P=0.691N     P=0.500N     P=0.247N   |               P=0.500N     P=0.753N     P=0.500N   |
|=================================================================================================================================|
|                                                                                                                                 |
|Harderian Gland                                                                                                                  |
|     Carcinoma or Adenoma                                                                                                        |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  3/50 (6%)    2/50 (4%)    2/50 (4%)    2/50 (4%)  |  2/50 (4%)    4/50 (8%)    2/50 (4%)    1/50 (2%)  |
|ADJUSTED (b)           |   7.5%         4.7%         5.5%         6.7%      |   7.1%        11.2%         5.6%         2.7%      |
|TERMINAL (d)           |  3/40 (8%)    1/37 (3%)    1/35 (3%)    2/30 (7%)  |  2/28 (7%)    2/32 (6%)    2/36 (6%)    1/37 (3%)  |
|FIRST INCIDENCE (DAYS) |   733 (T)      580          711          733 (T)   |   735 (T)      686          735 (T)      735 (T)   |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.543N     P=0.528N     P=0.555N     P=0.630N   |  P=0.190N     P=0.389      P=0.602N     P=0.403N   |
|INCIDENTAL TUMOR       |  P=0.455N     P=0.467N     P=0.568N     P=0.630N   |  P=0.212N     P=0.329      P=0.602N     P=0.403N   |
|LOGISTIC REGRESSION    |  P=0.463N     P=0.495N     P=0.556N     P=0.630N   |  P=0.219N     P=0.367      P=0.602N     P=0.402N   |
|COCHRAN-ARMITAGE       |  P=0.431N                                          |  P=0.263N                                          |
|FISHER EXACT           |               P=0.500N     P=0.500N     P=0.500N   |               P=0.339      P=0.691N     P=0.500N   |
|=================================================================================================================================|
         DATE: 09/23/96                     EXPERIMENT: 60968 TEST: 02                                                 PAGE   4
                              STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- 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)            |  0/50 (0%)    0/49 (0%)    0/50 (0%)    0/50 (0%)  |  0/50 (0%)    0/49 (0%)    2/50 (4%)    0/50 (0%)  |
|ADJUSTED (b)           |   0.0%         0.0%         0.0%         0.0%      |   0.0%         0.0%         5.0%         0.0%      |
|TERMINAL (d)           |  0/40 (0%)    0/37 (0%)    0/35 (0%)    0/30 (0%)  |  0/28 (0%)    0/32 (0%)    1/36 (3%)    0/37 (0%)  |
|FIRST INCIDENCE (DAYS) |   ---          ---          ---          ---       |   ---          ---          631          ---       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |    (e)          (e)          (e)          (e)      |  P=0.633        (e)        P=0.273        (e)      |
|INCIDENTAL TUMOR       |    (e)          (e)          (e)          (e)      |  P=0.529        (e)        P=0.301        (e)      |
|LOGISTIC REGRESSION    |    (e)          (e)          (e)          (e)      |  P=0.592        (e)        P=0.234        (e)      |
|COCHRAN-ARMITAGE       |    (e)                                             |  P=0.596                                           |
|FISHER EXACT           |                 (e)          (e)          (e)      |                 (e)        P=0.247        (e)      |
|=================================================================================================================================|
|                                                                                                                                 |
|Islets, Pancreatic                                                                                                               |
|     Carcinoma or Adenoma                                                                                                        |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  1/50 (2%)    0/49 (0%)    1/50 (2%)    1/50 (2%)  |  1/50 (2%)    1/49 (2%)    3/50 (6%)    0/50 (0%)  |
|ADJUSTED (b)           |   2.5%         0.0%         2.9%         3.3%      |   2.5%         3.0%         7.3%         0.0%      |
|TERMINAL (d)           |  1/40 (3%)    0/37 (0%)    1/35 (3%)    1/30 (3%)  |  0/28 (0%)    0/32 (0%)    1/36 (3%)    0/37 (0%)  |
|FIRST INCIDENCE (DAYS) |   733 (T)      ---          733 (T)      733 (T)   |   639          731          631          ---       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.467      P=0.516N     P=0.732      P=0.696    |  P=0.354N     P=0.742N     P=0.339      P=0.472N   |
|INCIDENTAL TUMOR       |  P=0.467      P=0.516N     P=0.732      P=0.696    |  P=0.608N     P=0.725      P=0.405      P=0.846N   |
|LOGISTIC REGRESSION    |  P=0.467      P=0.516N     P=0.732      P=0.696    |  P=0.424N     P=0.761      P=0.273      P=0.526N   |
|COCHRAN-ARMITAGE       |  P=0.541                                           |  P=0.407N                                          |
|FISHER EXACT           |               P=0.505N     P=0.753N     P=0.753N   |               P=0.747      P=0.309      P=0.500N   |
|=================================================================================================================================|
         DATE: 09/23/96                     EXPERIMENT: 60968 TEST: 02                                                 PAGE   5
                              STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- 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)            | 12/49 (24%)  14/50 (28%)  15/50 (30%)   7/50 (14%) |  9/49 (18%)  12/49 (24%)  11/50 (22%)   9/50 (18%) |
|ADJUSTED (b)           |  29.7%        33.4%        38.1%        19.0%      |  26.3%        33.5%        28.4%        22.4%      |
|TERMINAL (d)           | 11/39 (28%)  10/37 (27%)  11/35 (31%)   3/30 (10%) |  5/28 (18%)   9/32 (28%)   9/36 (25%)   7/37 (19%) |
|FIRST INCIDENCE (DAYS) |   639          605          535          639       |   583          636          581          611       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.282N     P=0.354      P=0.219      P=0.320N   |  P=0.254N     P=0.416      P=0.585      P=0.396N   |
|INCIDENTAL TUMOR       |  P=0.102N     P=0.466      P=0.251      P=0.145N   |  P=0.397N     P=0.345      P=0.518      P=0.603N   |
|LOGISTIC REGRESSION    |  P=0.124N     P=0.422      P=0.250      P=0.174N   |  P=0.379N     P=0.359      P=0.476      P=0.534N   |
|COCHRAN-ARMITAGE       |  P=0.100N                                          |  P=0.440N                                          |
|FISHER EXACT           |               P=0.433      P=0.349      P=0.142N   |               P=0.312      P=0.421      P=0.584N   |
|=================================================================================================================================|
|                                                                                                                                 |
|Liver                                                                                                                            |
|     Hepatocellular Carcinoma                                                                                                    |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            | 17/49 (35%)  14/50 (28%)  12/50 (24%)  13/50 (26%) |  6/49 (12%)   9/49 (18%)   4/50 (8%)    3/50 (6%)  |
|ADJUSTED (b)           |  37.3%        30.2%        27.9%        32.4%      |  16.7%        21.6%        10.8%         7.8%      |
|TERMINAL (d)           | 11/39 (28%)   5/37 (14%)   6/35 (17%)   5/30 (17%) |  3/28 (11%)   2/32 (6%)    3/36 (8%)    2/37 (5%)  |
|FIRST INCIDENCE (DAYS) |   639          580          410          547       |   543          527          713          682       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.448N     P=0.410N     P=0.326N     P=0.501N   |  P=0.060N     P=0.361      P=0.268N     P=0.168N   |
|INCIDENTAL TUMOR       |  P=0.048N*    P=0.140N     P=0.166N     P=0.067N   |  P=0.087N     P=0.265      P=0.324N     P=0.302N   |
|LOGISTIC REGRESSION    |  P=0.092N     P=0.258N     P=0.120N     P=0.123N   |  P=0.097N     P=0.265      P=0.349N     P=0.236N   |
|COCHRAN-ARMITAGE       |  P=0.212N                                          |  P=0.090N                                          |
|FISHER EXACT           |               P=0.308N     P=0.172N     P=0.235N   |               P=0.288      P=0.357N     P=0.233N   |
|=================================================================================================================================|
         DATE: 09/23/96                     EXPERIMENT: 60968 TEST: 02                                                 PAGE   6
                              STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- 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)            | 27/49 (55%)  25/50 (50%)  26/50 (52%)  18/50 (36%) | 12/49 (24%)  20/49 (41%)  15/50 (30%)  12/50 (24%) |
|ADJUSTED (b)           |  58.4%        52.1%        57.4%        43.8%      |  32.8%        47.8%        38.1%        29.4%      |
|TERMINAL (d)           | 20/39 (51%)  14/37 (38%)  16/35 (46%)   8/30 (27%) |  6/28 (21%)  11/32 (34%)  12/36 (33%)   9/37 (24%) |
|FIRST INCIDENCE (DAYS) |   639          580          410          547       |   543          527          581          611       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.276N     P=0.523N     P=0.427      P=0.289N   |  P=0.143N     P=0.149      P=0.546      P=0.364N   |
|INCIDENTAL TUMOR       |  P=0.006N**   P=0.210N     P=0.548N     P=0.010N** |  P=0.255N     P=0.070      P=0.424      P=0.583    |
|LOGISTIC REGRESSION    |  P=0.012N*    P=0.291N     P=0.567N     P=0.020N*  |  P=0.263N     P=0.072      P=0.401      P=0.530N   |
|COCHRAN-ARMITAGE       |  P=0.035N*                                         |  P=0.300N                                          |
|FISHER EXACT           |               P=0.380N     P=0.457N     P=0.044N*  |               P=0.065      P=0.349      P=0.570N   |
|=================================================================================================================================|
|                                                                                                                                 |
|Liver                                                                                                                            |
|     Hepatocellular Carcinoma, Hepatocellular Adenoma, or Hepatoblastoma                                                         |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            | 27/49 (55%)  25/50 (50%)  26/50 (52%)  18/50 (36%) | 12/49 (24%)  20/49 (41%)  15/50 (30%)  12/50 (24%) |
|ADJUSTED (b)           |  58.4%        52.1%        57.4%        43.8%      |  32.8%        47.8%        38.1%        29.4%      |
|TERMINAL (d)           | 20/39 (51%)  14/37 (38%)  16/35 (46%)   8/30 (27%) |  6/28 (21%)  11/32 (34%)  12/36 (33%)   9/37 (24%) |
|FIRST INCIDENCE (DAYS) |   639          580          410          547       |   543          527          581          611       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.276N     P=0.523N     P=0.427      P=0.289N   |  P=0.143N     P=0.149      P=0.546      P=0.364N   |
|INCIDENTAL TUMOR       |  P=0.006N**   P=0.210N     P=0.548N     P=0.010N** |  P=0.255N     P=0.070      P=0.424      P=0.583    |
|LOGISTIC REGRESSION    |  P=0.012N*    P=0.291N     P=0.567N     P=0.020N*  |  P=0.263N     P=0.072      P=0.401      P=0.530N   |
|COCHRAN-ARMITAGE       |  P=0.035N*                                         |  P=0.300N                                          |
|FISHER EXACT           |               P=0.380N     P=0.457N     P=0.044N*  |               P=0.065      P=0.349      P=0.570N   |
|=================================================================================================================================|
         DATE: 09/23/96                     EXPERIMENT: 60968 TEST: 02                                                 PAGE   7
                              STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- ISOBUTYRALDEHYDE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      500 PPM      1000 PPM     2000 PPM  |   CONTROL      500 PPM      1000 PPM     2000 PPM  |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Liver                                                                                                                            |
|     Hepatocholangiocarcinoma                                                                                                    |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  0/49 (0%)    1/50 (2%)    0/50 (0%)    0/50 (0%)  |  2/49 (4%)    1/49 (2%)    0/50 (0%)    0/50 (0%)  |
|ADJUSTED (b)           |   0.0%         2.0%         0.0%         0.0%      |   4.8%         3.1%         0.0%         0.0%      |
|TERMINAL (d)           |  0/39 (0%)    0/37 (0%)    0/35 (0%)    0/30 (0%)  |  0/28 (0%)    1/32 (3%)    0/36 (0%)    0/37 (0%)  |
|FIRST INCIDENCE (DAYS) |   ---          573          ---          ---       |   596          735 (T)      ---          ---       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.577N     P=0.504        (e)          (e)      |  P=0.087N     P=0.477N     P=0.235N     P=0.215N   |
|INCIDENTAL TUMOR       |  P=0.500N     P=0.638        (e)          (e)      |  P=0.120N     P=0.510N     P=0.277N     P=0.424N   |
|LOGISTIC REGRESSION    |  P=0.542N     P=0.546        (e)          (e)      |  P=0.106N     P=0.512N     P=0.266N     P=0.264N   |
|COCHRAN-ARMITAGE       |  P=0.565N                                          |  P=0.098N                                          |
|FISHER EXACT           |               P=0.505        (e)          (e)      |               P=0.500N     P=0.242N     P=0.242N   |
|=================================================================================================================================|
|                                                                                                                                 |
|Lung                                                                                                                             |
|     Alveolar/Bronchiolar Adenoma                                                                                                |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  5/50 (10%)   3/50 (6%)    6/50 (12%)   5/50 (10%) |  0/50 (0%)    1/50 (2%)    1/50 (2%)    3/50 (6%)  |
|ADJUSTED (b)           |  12.1%         7.8%        17.1%        15.7%      |   0.0%         3.1%         2.4%         8.1%      |
|TERMINAL (d)           |  4/40 (10%)   2/37 (5%)    6/35 (17%)   4/30 (13%) |  0/28 (0%)    1/32 (3%)    0/36 (0%)    3/37 (8%)  |
|FIRST INCIDENCE (DAYS) |   682          712          733 (T)      670       |   ---          735 (T)      645          735 (T)   |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.281      P=0.396N     P=0.408      P=0.459    |  P=0.082      P=0.527      P=0.510      P=0.174    |
|INCIDENTAL TUMOR       |  P=0.400      P=0.364N     P=0.402      P=0.592    |  P=0.075      P=0.527      P=0.343      P=0.174    |
|LOGISTIC REGRESSION    |  P=0.352      P=0.371N     P=0.414      P=0.556    |  P=0.062      P=0.527      P=0.475      P=0.172    |
|COCHRAN-ARMITAGE       |  P=0.451                                           |  P=0.054                                           |
|FISHER EXACT           |               P=0.357N     P=0.500      P=0.630N   |               P=0.500      P=0.500      P=0.121    |
|=================================================================================================================================|
         DATE: 09/23/96                     EXPERIMENT: 60968 TEST: 02                                                 PAGE   8
                              STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- 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 Carcinoma                                                                                              |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  7/50 (14%)   6/50 (12%)   4/50 (8%)    6/50 (12%) |  3/50 (6%)    0/50 (0%)    2/50 (4%)    1/50 (2%)  |
|ADJUSTED (b)           |  15.6%        16.2%        10.7%        16.5%      |   9.2%         0.0%         5.6%         2.7%      |
|TERMINAL (d)           |  4/40 (10%)   6/37 (16%)   3/35 (9%)    3/30 (10%) |  2/28 (7%)    0/32 (0%)    2/36 (6%)    1/37 (3%)  |
|FIRST INCIDENCE (DAYS) |   455          733 (T)      535          499       |   543          ---          735 (T)      735 (T)   |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.529      P=0.557N     P=0.352N     P=0.582    |  P=0.266N     P=0.105N     P=0.404N     P=0.234N   |
|INCIDENTAL TUMOR       |  P=0.430N     P=0.535N     P=0.233N     P=0.431N   |  P=0.249N     P=0.107N     P=0.469N     P=0.204N   |
|LOGISTIC REGRESSION    |  P=0.417N     P=0.487N     P=0.224N     P=0.399N   |  P=0.324N     P=0.122N     P=0.485N     P=0.301N   |
|COCHRAN-ARMITAGE       |  P=0.426N                                          |  P=0.337N                                          |
|FISHER EXACT           |               P=0.500N     P=0.262N     P=0.500N   |               P=0.121N     P=0.500N     P=0.309N   |
|=================================================================================================================================|
|                                                                                                                                 |
|Lung                                                                                                                             |
|     Alveolar/Bronchiolar Carcinoma or Alveolar/Bronchiolar Adenoma                                                              |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            | 12/50 (24%)   8/50 (16%)  10/50 (20%)  10/50 (20%) |  3/50 (6%)    1/50 (2%)    3/50 (6%)    4/50 (8%)  |
|ADJUSTED (b)           |  26.7%        21.0%        27.4%        27.8%      |   9.2%         3.1%         7.9%        10.8%      |
|TERMINAL (d)           |  8/40 (20%)   7/37 (19%)   9/35 (26%)   6/30 (20%) |  2/28 (7%)    1/32 (3%)    2/36 (6%)    4/37 (11%) |
|FIRST INCIDENCE (DAYS) |   455          712          535          499       |   543          735 (T)      645          735 (T)   |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.398      P=0.291N     P=0.547N     P=0.550    |  P=0.389      P=0.268N     P=0.573N     P=0.630    |
|INCIDENTAL TUMOR       |  P=0.479N     P=0.253N     P=0.452N     P=0.366N   |  P=0.394      P=0.271N     P=0.632      P=0.649N   |
|LOGISTIC REGRESSION    |  P=0.488N     P=0.224N     P=0.454N     P=0.355N   |  P=0.306      P=0.300N     P=0.661N     P=0.533    |
|COCHRAN-ARMITAGE       |  P=0.452N                                          |  P=0.282                                           |
|FISHER EXACT           |               P=0.227N     P=0.405N     P=0.405N   |               P=0.309N     P=0.661N     P=0.500    |
|=================================================================================================================================|
         DATE: 09/23/96                     EXPERIMENT: 60968 TEST: 02                                                 PAGE   9
                              STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- 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%)    2/50 (4%)    0/50 (0%)  |
|ADJUSTED (b)           |   0.0%         0.0%         0.0%         0.0%      |   3.6%         2.6%         5.2%         0.0%      |
|TERMINAL (d)           |  0/40 (0%)    0/37 (0%)    0/35 (0%)    0/30 (0%)  |  1/28 (4%)    0/32 (0%)    0/36 (0%)    0/37 (0%)  |
|FIRST INCIDENCE (DAYS) |   ---          ---          ---          ---       |   735 (T)      686          665          ---       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |    (e)          (e)          (e)          (e)      |  P=0.323N     P=0.739N     P=0.566      P=0.444N   |
|INCIDENTAL TUMOR       |    (e)          (e)          (e)          (e)      |  P=0.396N     P=0.741      P=0.349      P=0.444N   |
|LOGISTIC REGRESSION    |    (e)          (e)          (e)          (e)      |  P=0.358N     P=0.752N     P=0.518      P=0.444N   |
|COCHRAN-ARMITAGE       |    (e)                                             |  P=0.366N                                          |
|FISHER EXACT           |                 (e)          (e)          (e)      |               P=0.753N     P=0.500      P=0.500N   |
|=================================================================================================================================|
|                                                                                                                                 |
|Ovary                                                                                                                            |
|     Cystadenocarcinoma                                                                                                          |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |                                                    |  0/50 (0%)    2/49 (4%)    0/50 (0%)    0/50 (0%)  |
|ADJUSTED (b)           |                                                    |   0.0%         6.3%         0.0%         0.0%      |
|TERMINAL (d)           |                                                    |  0/28 (0%)    2/32 (6%)    0/36 (0%)    0/37 (0%)  |
|FIRST INCIDENCE (DAYS) |                                                    |   ---          735 (T)      ---          ---       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |                                                    |  P=0.352N     P=0.268        (e)          (e)      |
|INCIDENTAL TUMOR       |                                                    |  P=0.352N     P=0.268        (e)          (e)      |
|LOGISTIC REGRESSION    |                                                    |  P=0.352N     P=0.268        (e)          (e)      |
|COCHRAN-ARMITAGE       |                                                    |  P=0.404N                                          |
|FISHER EXACT           |                                                    |               P=0.242        (e)          (e)      |
|=================================================================================================================================|
         DATE: 09/23/96                     EXPERIMENT: 60968 TEST: 02                                                 PAGE  10
                              STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- ISOBUTYRALDEHYDE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      500 PPM      1000 PPM     2000 PPM  |   CONTROL      500 PPM      1000 PPM     2000 PPM  |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Ovary                                                                                                                            |
|     Cystadenoma                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |                                                    |  1/50 (2%)    5/49 (10%)   1/50 (2%)    2/50 (4%)  |
|ADJUSTED (b)           |                                                    |   3.6%        14.6%         2.8%         4.9%      |
|TERMINAL (d)           |                                                    |  1/28 (4%)    4/32 (13%)   1/36 (3%)    1/37 (3%)  |
|FIRST INCIDENCE (DAYS) |                                                    |   735 (T)      623          735 (T)      653       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |                                                    |  P=0.417N     P=0.131      P=0.705N     P=0.587    |
|INCIDENTAL TUMOR       |                                                    |  P=0.487N     P=0.131      P=0.705N     P=0.541    |
|LOGISTIC REGRESSION    |                                                    |  P=0.489N     P=0.113      P=0.705N     P=0.522    |
|COCHRAN-ARMITAGE       |                                                    |  P=0.520N                                          |
|FISHER EXACT           |                                                    |               P=0.098      P=0.753N     P=0.500    |
|=================================================================================================================================|
|                                                                                                                                 |
|Pituitary Gland: Pars Distalis or Unspecified Site                                                                               |
|     Adenoma                                                                                                                     |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  0/49 (0%)    0/47 (0%)    0/49 (0%)    0/49 (0%)  | 10/50 (20%)   9/49 (18%)   6/50 (12%)   9/49 (18%) |
|ADJUSTED (b)           |   0.0%         0.0%         0.0%         0.0%      |  30.5%        27.7%        15.8%        24.0%      |
|TERMINAL (d)           |  0/39 (0%)    0/34 (0%)    0/35 (0%)    0/29 (0%)  |  7/28 (25%)   8/31 (26%)   4/36 (11%)   8/36 (22%) |
|FIRST INCIDENCE (DAYS) |   ---          ---          ---          ---       |   533          681          674          653       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |    (e)          (e)          (e)          (e)      |  P=0.240N     P=0.414N     P=0.111N     P=0.298N   |
|INCIDENTAL TUMOR       |    (e)          (e)          (e)          (e)      |  P=0.275N     P=0.470N     P=0.238N     P=0.324N   |
|LOGISTIC REGRESSION    |    (e)          (e)          (e)          (e)      |  P=0.354N     P=0.468N     P=0.169N     P=0.447N   |
|COCHRAN-ARMITAGE       |    (e)                                             |  P=0.437N                                          |
|FISHER EXACT           |                 (e)          (e)          (e)      |               P=0.520N     P=0.207N     P=0.520N   |
|=================================================================================================================================|
         DATE: 09/23/96                     EXPERIMENT: 60968 TEST: 02                                                 PAGE  11
                              STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- 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)            |  2/50 (4%)    0/50 (0%)    2/50 (4%)    0/50 (0%)  |  0/50 (0%)    1/50 (2%)    0/50 (0%)    2/50 (4%)  |
|ADJUSTED (b)           |   4.4%         0.0%         4.8%         0.0%      |   0.0%         2.4%         0.0%         4.6%      |
|TERMINAL (d)           |  0/40 (0%)    0/37 (0%)    1/35 (3%)    0/30 (0%)  |  0/28 (0%)    0/32 (0%)    0/36 (0%)    0/37 (0%)  |
|FIRST INCIDENCE (DAYS) |   520          ---          322          ---       |   ---          636          ---          611       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.277N     P=0.242N     P=0.659      P=0.259N   |  P=0.158      P=0.500        (e)        P=0.261    |
|INCIDENTAL TUMOR       |  P=0.135N     P=0.290N     P=0.440N     P=0.148N   |  P=0.032 *    P=0.531        (e)        P=0.068    |
|LOGISTIC REGRESSION    |  P=0.177N     P=0.194N     P=0.514N     P=0.155N   |  P=0.112      P=0.487        (e)        P=0.208    |
|COCHRAN-ARMITAGE       |  P=0.247N                                          |  P=0.140                                           |
|FISHER EXACT           |               P=0.247N     P=0.691N     P=0.247N   |               P=0.500        (e)        P=0.247    |
|=================================================================================================================================|
|                                                                                                                                 |
|Skin                                                                                                                             |
|     Fibrosarcoma                                                                                                                |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  1/50 (2%)    0/50 (0%)    0/50 (0%)    0/50 (0%)  |  0/50 (0%)    1/50 (2%)    0/50 (0%)    2/50 (4%)  |
|ADJUSTED (b)           |   2.0%         0.0%         0.0%         0.0%      |   0.0%         2.4%         0.0%         4.6%      |
|TERMINAL (d)           |  0/40 (0%)    0/37 (0%)    0/35 (0%)    0/30 (0%)  |  0/28 (0%)    0/32 (0%)    0/36 (0%)    0/37 (0%)  |
|FIRST INCIDENCE (DAYS) |   520          ---          ---          ---       |   ---          636          ---          611       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.312N     P=0.500N     P=0.521N     P=0.504N   |  P=0.158      P=0.500        (e)        P=0.261    |
|INCIDENTAL TUMOR       |  P=0.244N     P=0.638N     P=0.318N     P=0.500N   |  P=0.032 *    P=0.531        (e)        P=0.068    |
|LOGISTIC REGRESSION    |  P=0.245N     P=0.434N     P=0.355N     P=0.379N   |  P=0.112      P=0.487        (e)        P=0.208    |
|COCHRAN-ARMITAGE       |  P=0.306N                                          |  P=0.140                                           |
|FISHER EXACT           |               P=0.500N     P=0.500N     P=0.500N   |               P=0.500        (e)        P=0.247    |
|=================================================================================================================================|
         DATE: 09/23/96                     EXPERIMENT: 60968 TEST: 02                                                 PAGE  12
                              STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- ISOBUTYRALDEHYDE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      500 PPM      1000 PPM     2000 PPM  |   CONTROL      500 PPM      1000 PPM     2000 PPM  |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Skin                                                                                                                             |
|     Fibrosarcoma, Sarcoma, Myxosarcoma, or Fibrous Histiocytoma                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  2/50 (4%)    0/50 (0%)    2/50 (4%)    0/50 (0%)  |  0/50 (0%)    1/50 (2%)    0/50 (0%)    2/50 (4%)  |
|ADJUSTED (b)           |   4.4%         0.0%         4.8%         0.0%      |   0.0%         2.4%         0.0%         4.6%      |
|TERMINAL (d)           |  0/40 (0%)    0/37 (0%)    1/35 (3%)    0/30 (0%)  |  0/28 (0%)    0/32 (0%)    0/36 (0%)    0/37 (0%)  |
|FIRST INCIDENCE (DAYS) |   520          ---          322          ---       |   ---          636          ---          611       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.277N     P=0.242N     P=0.659      P=0.259N   |  P=0.158      P=0.500        (e)        P=0.261    |
|INCIDENTAL TUMOR       |  P=0.135N     P=0.290N     P=0.440N     P=0.148N   |  P=0.032 *    P=0.531        (e)        P=0.068    |
|LOGISTIC REGRESSION    |  P=0.177N     P=0.194N     P=0.514N     P=0.155N   |  P=0.112      P=0.487        (e)        P=0.208    |
|COCHRAN-ARMITAGE       |  P=0.247N                                          |  P=0.140                                           |
|FISHER EXACT           |               P=0.247N     P=0.691N     P=0.247N   |               P=0.500        (e)        P=0.247    |
|=================================================================================================================================|
|                                                                                                                                 |
|Skin                                                                                                                             |
|     Hemangiosarcoma                                                                                                             |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  0/50 (0%)    0/50 (0%)    0/50 (0%)    1/50 (2%)  |  0/50 (0%)    2/50 (4%)    1/50 (2%)    0/50 (0%)  |
|ADJUSTED (b)           |   0.0%         0.0%         0.0%         3.3%      |   0.0%         5.3%         2.8%         0.0%      |
|TERMINAL (d)           |  0/40 (0%)    0/37 (0%)    0/35 (0%)    1/30 (3%)  |  0/28 (0%)    0/32 (0%)    1/36 (3%)    0/37 (0%)  |
|FIRST INCIDENCE (DAYS) |   ---          ---          ---          733 (T)   |   ---          623          735 (T)      ---       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.165        (e)          (e)        P=0.443    |  P=0.415N     P=0.253      P=0.550        (e)      |
|INCIDENTAL TUMOR       |  P=0.165        (e)          (e)        P=0.443    |  P=0.540N     P=0.221      P=0.550        (e)      |
|LOGISTIC REGRESSION    |  P=0.165        (e)          (e)        P=0.443    |  P=0.461N     P=0.232      P=0.550        (e)      |
|COCHRAN-ARMITAGE       |  P=0.198                                           |  P=0.461N                                          |
|FISHER EXACT           |                 (e)          (e)        P=0.500    |               P=0.247      P=0.500        (e)      |
|=================================================================================================================================|
         DATE: 09/23/96                     EXPERIMENT: 60968 TEST: 02                                                 PAGE  13
                              STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- ISOBUTYRALDEHYDE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      500 PPM      1000 PPM     2000 PPM  |   CONTROL      500 PPM      1000 PPM     2000 PPM  |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Spleen                                                                                                                           |
|     Hemangiosarcoma                                                                                                             |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  1/50 (2%)    2/50 (4%)    1/50 (2%)    0/50 (0%)  |  0/50 (0%)    1/49 (2%)    1/50 (2%)    0/50 (0%)  |
|ADJUSTED (b)           |   2.5%         5.4%         2.8%         0.0%      |   0.0%         2.4%         2.8%         0.0%      |
|TERMINAL (d)           |  1/40 (3%)    2/37 (5%)    0/35 (0%)    0/30 (0%)  |  0/28 (0%)    0/32 (0%)    1/36 (3%)    0/37 (0%)  |
|FIRST INCIDENCE (DAYS) |   733 (T)      733 (T)      728          ---       |   ---          623          735 (T)      ---       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.313N     P=0.473      P=0.734      P=0.557N   |  P=0.557N     P=0.500      P=0.550        (e)      |
|INCIDENTAL TUMOR       |  P=0.240N     P=0.473      P=0.720      P=0.557N   |  P=0.685N     P=0.500      P=0.550        (e)      |
|LOGISTIC REGRESSION    |  P=0.297N     P=0.473      P=0.737      P=0.557N   |  P=0.602N     P=0.478      P=0.550        (e)      |
|COCHRAN-ARMITAGE       |  P=0.247N                                          |  P=0.593N                                          |
|FISHER EXACT           |               P=0.500      P=0.753N     P=0.500N   |               P=0.495      P=0.500        (e)      |
|=================================================================================================================================|
|                                                                                                                                 |
|Stomach, Forestomach                                                                                                             |
|     Squamous Cell Papilloma                                                                                                     |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  1/50 (2%)    0/50 (0%)    1/50 (2%)    0/50 (0%)  |  0/50 (0%)    0/50 (0%)    3/50 (6%)    1/50 (2%)  |
|ADJUSTED (b)           |   2.5%         0.0%         2.6%         0.0%      |   0.0%         0.0%         8.3%         2.7%      |
|TERMINAL (d)           |  1/40 (3%)    0/37 (0%)    0/35 (0%)    0/30 (0%)  |  0/28 (0%)    0/32 (0%)    3/36 (8%)    1/37 (3%)  |
|FIRST INCIDENCE (DAYS) |   733 (T)      ---          672          ---       |   ---          ---          735 (T)      735 (T)   |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.451N     P=0.516N     P=0.732      P=0.557N   |  P=0.313        (e)        P=0.168      P=0.556    |
|INCIDENTAL TUMOR       |  P=0.340N     P=0.516N     P=0.720      P=0.557N   |  P=0.313        (e)        P=0.168      P=0.556    |
|LOGISTIC REGRESSION    |  P=0.410N     P=0.516N     P=0.754      P=0.557N   |  P=0.313        (e)        P=0.168      P=0.556    |
|COCHRAN-ARMITAGE       |  P=0.405N                                          |  P=0.247                                           |
|FISHER EXACT           |               P=0.500N     P=0.753N     P=0.500N   |                 (e)        P=0.121      P=0.500    |
|=================================================================================================================================|
         DATE: 09/23/96                     EXPERIMENT: 60968 TEST: 02                                                 PAGE  14
                              STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- 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                                                                                                   |
|     Adenoma                                                                                                                     |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  3/50 (6%)    2/50 (4%)    1/50 (2%)    5/50 (10%) |  3/50 (6%)    1/50 (2%)    2/50 (4%)    1/50 (2%)  |
|ADJUSTED (b)           |   7.0%         5.4%         2.9%        16.0%      |  10.7%         3.1%         5.6%         2.7%      |
|TERMINAL (d)           |  2/40 (5%)    2/37 (5%)    1/35 (3%)    4/30 (13%) |  3/28 (11%)   1/32 (3%)    2/36 (6%)    1/37 (3%)  |
|FIRST INCIDENCE (DAYS) |   639          733 (T)      733 (T)      723       |   735 (T)      735 (T)      735 (T)      735 (T)   |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.129      P=0.538N     P=0.362N     P=0.229    |  P=0.197N     P=0.257N     P=0.385N     P=0.211N   |
|INCIDENTAL TUMOR       |  P=0.182      P=0.467N     P=0.343N     P=0.339    |  P=0.197N     P=0.257N     P=0.385N     P=0.211N   |
|LOGISTIC REGRESSION    |  P=0.168      P=0.504N     P=0.332N     P=0.298    |  P=0.197N     P=0.257N     P=0.385N     P=0.211N   |
|COCHRAN-ARMITAGE       |  P=0.216                                           |  P=0.279N                                          |
|FISHER EXACT           |               P=0.500N     P=0.309N     P=0.357    |               P=0.309N     P=0.500N     P=0.309N   |
|=================================================================================================================================|
|                                                                                                                                 |
|Thyroid Gland: Follicular Cell                                                                                                   |
|     Carcinoma or Adenoma                                                                                                        |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  4/50 (8%)    2/50 (4%)    2/50 (4%)    5/50 (10%) |  3/50 (6%)    1/50 (2%)    2/50 (4%)    1/50 (2%)  |
|ADJUSTED (b)           |   9.0%         5.4%         5.3%        16.0%      |  10.7%         3.1%         5.6%         2.7%      |
|TERMINAL (d)           |  2/40 (5%)    2/37 (5%)    1/35 (3%)    4/30 (13%) |  3/28 (11%)   1/32 (3%)    2/36 (6%)    1/37 (3%)  |
|FIRST INCIDENCE (DAYS) |   639          733 (T)      649          723       |   735 (T)      735 (T)      735 (T)      735 (T)   |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.225      P=0.380N     P=0.415N     P=0.355    |  P=0.197N     P=0.257N     P=0.385N     P=0.211N   |
|INCIDENTAL TUMOR       |  P=0.349      P=0.258N     P=0.384N     P=0.531    |  P=0.197N     P=0.257N     P=0.385N     P=0.211N   |
|LOGISTIC REGRESSION    |  P=0.301      P=0.331N     P=0.331N     P=0.470    |  P=0.197N     P=0.257N     P=0.385N     P=0.211N   |
|COCHRAN-ARMITAGE       |  P=0.331                                           |  P=0.279N                                          |
|FISHER EXACT           |               P=0.339N     P=0.339N     P=0.500    |               P=0.309N     P=0.500N     P=0.309N   |
|=================================================================================================================================|
         DATE: 09/23/96                     EXPERIMENT: 60968 TEST: 02                                                 PAGE  15
                              STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- ISOBUTYRALDEHYDE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      500 PPM      1000 PPM     2000 PPM  |   CONTROL      500 PPM      1000 PPM     2000 PPM  |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Uterus                                                                                                                           |
|     Polyp Stromal                                                                                                               |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |                                                    |  2/50 (4%)    2/50 (4%)    1/50 (2%)    5/50 (10%) |
|ADJUSTED (b)           |                                                    |   5.6%         6.3%         2.8%        13.5%      |
|TERMINAL (d)           |                                                    |  1/28 (4%)    2/32 (6%)    1/36 (3%)    5/37 (14%) |
|FIRST INCIDENCE (DAYS) |                                                    |   344          735 (T)      735 (T)      735 (T)   |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |                                                    |  P=0.179      P=0.656N     P=0.437N     P=0.325    |
|INCIDENTAL TUMOR       |                                                    |  P=0.094      P=0.643      P=0.705N     P=0.176    |
|LOGISTIC REGRESSION    |                                                    |  P=0.116      P=0.674      P=0.592N     P=0.207    |
|COCHRAN-ARMITAGE       |                                                    |  P=0.114                                           |
|FISHER EXACT           |                                                    |               P=0.691N     P=0.500N     P=0.218    |
|=================================================================================================================================|
|                                                                                                                                 |
|All Organs                                                                                                                       |
|     Hemangiosarcoma                                                                                                             |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  2/50 (4%)    2/50 (4%)    1/50 (2%)    1/50 (2%)  |  2/50 (4%)    4/50 (8%)    4/50 (8%)    1/50 (2%)  |
|ADJUSTED (b)           |   5.0%         5.4%         2.8%         3.3%      |   7.1%         9.9%        11.1%         2.6%      |
|TERMINAL (d)           |  2/40 (5%)    2/37 (5%)    0/35 (0%)    1/30 (3%)  |  2/28 (7%)    0/32 (0%)    4/36 (11%)   0/37 (0%)  |
|FIRST INCIDENCE (DAYS) |   733 (T)      733 (T)      728          733 (T)   |   735 (T)      595          735 (T)      702       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.432N     P=0.667      P=0.543N     P=0.600N   |  P=0.233N     P=0.388      P=0.457      P=0.409N   |
|INCIDENTAL TUMOR       |  P=0.359N     P=0.667      P=0.557N     P=0.600N   |  P=0.355N     P=0.332      P=0.457      P=0.459N   |
|LOGISTIC REGRESSION    |  P=0.413N     P=0.667      P=0.540N     P=0.600N   |  P=0.300N     P=0.339      P=0.457      P=0.454N   |
|COCHRAN-ARMITAGE       |  P=0.337N                                          |  P=0.319N                                          |
|FISHER EXACT           |               P=0.691N     P=0.500N     P=0.500N   |               P=0.339      P=0.339      P=0.500N   |
|=================================================================================================================================|
         DATE: 09/23/96                     EXPERIMENT: 60968 TEST: 02                                                 PAGE  16
                              STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- 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                                                                                                                       |
|     Hemangiosarcoma or Hemangioma                                                                                               |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  2/50 (4%)    2/50 (4%)    1/50 (2%)    1/50 (2%)  |  2/50 (4%)    4/50 (8%)    5/50 (10%)   1/50 (2%)  |
|ADJUSTED (b)           |   5.0%         5.4%         2.8%         3.3%      |   7.1%         9.9%        13.3%         2.6%      |
|TERMINAL (d)           |  2/40 (5%)    2/37 (5%)    0/35 (0%)    1/30 (3%)  |  2/28 (7%)    0/32 (0%)    4/36 (11%)   0/37 (0%)  |
|FIRST INCIDENCE (DAYS) |   733 (T)      733 (T)      728          733 (T)   |   735 (T)      595          653          702       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.432N     P=0.667      P=0.543N     P=0.600N   |  P=0.253N     P=0.388      P=0.317      P=0.409N   |
|INCIDENTAL TUMOR       |  P=0.359N     P=0.667      P=0.557N     P=0.600N   |  P=0.389N     P=0.332      P=0.259      P=0.459N   |
|LOGISTIC REGRESSION    |  P=0.413N     P=0.667      P=0.540N     P=0.600N   |  P=0.329N     P=0.339      P=0.256      P=0.454N   |
|COCHRAN-ARMITAGE       |  P=0.337N                                          |  P=0.344N                                          |
|FISHER EXACT           |               P=0.691N     P=0.500N     P=0.500N   |               P=0.339      P=0.218      P=0.500N   |
|=================================================================================================================================|
|                                                                                                                                 |
|All Organs                                                                                                                       |
|     Histiocytic Sarcoma                                                                                                         |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  0/50 (0%)    0/50 (0%)    0/50 (0%)    0/50 (0%)  |  1/50 (2%)    0/50 (0%)    3/50 (6%)    1/50 (2%)  |
|ADJUSTED (b)           |   0.0%         0.0%         0.0%         0.0%      |   3.6%         0.0%         7.4%         2.7%      |
|TERMINAL (d)           |  0/40 (0%)    0/37 (0%)    0/35 (0%)    0/30 (0%)  |  1/28 (4%)    0/32 (0%)    1/36 (3%)    1/37 (3%)  |
|FIRST INCIDENCE (DAYS) |   ---          ---          ---          ---       |   735 (T)      ---          581          735 (T)   |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |    (e)          (e)          (e)          (e)      |  P=0.530      P=0.473N     P=0.360      P=0.699N   |
|INCIDENTAL TUMOR       |    (e)          (e)          (e)          (e)      |  P=0.443      P=0.473N     P=0.307      P=0.699N   |
|LOGISTIC REGRESSION    |    (e)          (e)          (e)          (e)      |  P=0.471      P=0.473N     P=0.299      P=0.699N   |
|COCHRAN-ARMITAGE       |    (e)                                             |  P=0.469                                           |
|FISHER EXACT           |                 (e)          (e)          (e)      |               P=0.500N     P=0.309      P=0.753N   |
|=================================================================================================================================|
         DATE: 09/23/96                     EXPERIMENT: 60968 TEST: 02                                                 PAGE  17
                              STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- 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 Lymphoma: Histiocytic, Lymphocytic, Mixed, NOS, or Undifferentiated                                               |
|     Cell Type                                                                                                                   |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  1/50 (2%)    5/50 (10%)   1/50 (2%)    6/50 (12%) | 12/50 (24%)  13/50 (26%)  12/50 (24%)  19/50 (38%) |
|ADJUSTED (b)           |   2.1%        13.5%         2.9%        16.8%      |  35.7%        35.0%        30.0%        47.3%      |
|TERMINAL (d)           |  0/40 (0%)    5/37 (14%)   1/35 (3%)    2/30 (7%)  |  8/28 (29%)   9/32 (28%)   9/36 (25%)  16/37 (43%) |
|FIRST INCIDENCE (DAYS) |   639          733 (T)      733 (T)      665       |   533          611          547          653       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.042 *    P=0.087      P=0.722      P=0.038 *  |  P=0.234      P=0.554N     P=0.378N     P=0.318    |
|INCIDENTAL TUMOR       |  P=0.125      P=0.114      P=0.746      P=0.163    |  P=0.114      P=0.567      P=0.491N     P=0.207    |
|LOGISTIC REGRESSION    |  P=0.067      P=0.100      P=0.766N     P=0.063    |  P=0.096      P=0.547      P=0.543N     P=0.151    |
|COCHRAN-ARMITAGE       |  P=0.080                                           |  P=0.068                                           |
|FISHER EXACT           |               P=0.102      P=0.753N     P=0.056    |               P=0.500      P=0.592N     P=0.097    |
|=================================================================================================================================|
|                                                                                                                                 |
|All Organs                                                                                                                       |
|     Benign Tumors                                                                                                               |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            | 22/50 (44%)  19/50 (38%)  22/50 (44%)  19/50 (38%) | 26/50 (52%)  34/50 (68%)  26/50 (52%)  25/50 (50%) |
|ADJUSTED (b)           |  50.9%        44.7%        54.5%        51.7%      |  70.9%        84.8%        60.4%        58.9%      |
|TERMINAL (d)           | 19/40 (48%)  14/37 (38%)  17/35 (49%)  13/30 (43%) | 18/28 (64%)  26/32 (81%)  19/36 (53%)  20/37 (54%) |
|FIRST INCIDENCE (DAYS) |   639          605          359          616       |   344          623          581          611       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.309      P=0.462N     P=0.356      P=0.409    |  P=0.032N*    P=0.243      P=0.230N     P=0.129N   |
|INCIDENTAL TUMOR       |  P=0.438N     P=0.312N     P=0.475      P=0.431N   |  P=0.109N     P=0.104      P=0.542N     P=0.375N   |
|LOGISTIC REGRESSION    |  P=0.455N     P=0.364N     P=0.444      P=0.474N   |  P=0.137N     P=0.114      P=0.476N     P=0.392N   |
|COCHRAN-ARMITAGE       |  P=0.367N                                          |  P=0.243N                                          |
|FISHER EXACT           |               P=0.342N     P=0.580N     P=0.342N   |               P=0.076      P=0.579N     P=0.500N   |
|=================================================================================================================================|
         DATE: 09/23/96                     EXPERIMENT: 60968 TEST: 02                                                 PAGE  18
                              STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- 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)            | 28/50 (56%)  27/50 (54%)  22/50 (44%)  25/50 (50%) | 25/50 (50%)  28/50 (56%)  26/50 (52%)  24/50 (48%) |
|ADJUSTED (b)           |  56.0%        57.3%        49.1%        56.1%      |  62.2%        58.8%        56.1%        55.7%      |
|TERMINAL (d)           | 18/40 (45%)  17/37 (46%)  13/35 (37%)  11/30 (37%) | 14/28 (50%)  13/32 (41%)  16/36 (44%)  18/37 (49%) |
|FIRST INCIDENCE (DAYS) |   455          573          322          499       |    76           93          537          611       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.406      P=0.512      P=0.389N     P=0.404    |  P=0.134N     P=0.530      P=0.342N     P=0.176N   |
|INCIDENTAL TUMOR       |  P=0.076N     P=0.371N     P=0.093N     P=0.096N   |  P=0.508N     P=0.339      P=0.503      P=0.552N   |
|LOGISTIC REGRESSION    |  P=0.127N     P=0.464N     P=0.090N     P=0.155N   |  P=0.428N     P=0.297      P=0.459      P=0.469N   |
|COCHRAN-ARMITAGE       |  P=0.267N                                          |  P=0.378N                                          |
|FISHER EXACT           |               P=0.500N     P=0.159N     P=0.344N   |               P=0.344      P=0.500      P=0.500N   |
|=================================================================================================================================|
|                                                                                                                                 |
|All Organs                                                                                                                       |
|     Malignant and Benign Tumors                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            | 40/50 (80%)  36/50 (72%)  39/50 (78%)  34/50 (68%) | 38/50 (76%)  45/50 (90%)  37/50 (74%)  40/50 (80%) |
|ADJUSTED (b)           |  80.0%        73.5%        81.2%        73.7%      |  90.0%        91.8%        77.0%        86.9%      |
|TERMINAL (d)           | 30/40 (75%)  24/37 (65%)  26/35 (74%)  18/30 (60%) | 24/28 (86%)  28/32 (88%)  25/36 (69%)  31/37 (84%) |
|FIRST INCIDENCE (DAYS) |   455          573          322          499       |    76           93          537          611       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.318      P=0.473N     P=0.304      P=0.414    |  P=0.070N     P=0.391      P=0.129N     P=0.143N   |
|INCIDENTAL TUMOR       |  P=0.046N*    P=0.154N     P=0.473N     P=0.050N*  |  P=0.499N     P=0.079      P=0.410N     P=0.442    |
|LOGISTIC REGRESSION    |  P=0.081N     P=0.223N     P=0.474N     P=0.073N   |  P=0.442N     P=0.060      P=0.486N     P=0.523    |
|COCHRAN-ARMITAGE       |  P=0.142N                                          |  P=0.500N                                          |
|FISHER EXACT           |               P=0.241N     P=0.500N     P=0.127N   |               P=0.054      P=0.500N     P=0.405    |
|=================================================================================================================================|
         DATE: 09/23/96                     EXPERIMENT: 60968 TEST: 02                                                 PAGE  19
                              STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- 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).