https://ntp.niehs.nih.gov/go/4410

TDMS Study 88034-04 Pathology Tables

NTP                                        STATISTICAL ANALYSIS OF PRIMARY TUMORS                              REPORT: PEIRPT08     
LAB: Battelle Northwest                                          OZONE                                         DATE: 05/08/95       
EXPERIMENT: 88034 TEST: 04                                                                                     TIME: 20:53:20       
TEST TYPE:  CHRONIC                             CAGES FROM 0000 TO LAST CAGE                                   PAGE:       1        
CONT: N01-ES-95239          ROUTE: RESPIRATORY EXPOSURE WHOLE BODY                                             NTP C#: C88034       
PATHOLOGIST: S. GRUMBEIN                                                                                       CAS: 10028-15-6      
------------------------------------------------------------------------------------------------------------------------------------
               REASONS FOR REMOVAL:    ALL                                                                                          
               REMOVAL DATE RANGE:     ALL                                                                                          
               TREATMENT GROUPS:       INCLUDE ALL                                                                                  
NTP                                        STATISTICAL ANALYSIS OF PRIMARY TUMORS                              REPORT: PEIRPT08     
LAB: Battelle Northwest                                          OZONE                                         DATE: 05/08/95       
EXPERIMENT: 88034 TEST: 04                                                                                     TIME: 20:53:20       
TEST TYPE:  CHRONIC                             CAGES FROM 0000 TO LAST CAGE                                                        
CONT: N01-ES-95239          ROUTE: RESPIRATORY EXPOSURE WHOLE BODY                                             NTP C#: C88034       
PATHOLOGIST: S. GRUMBEIN                                                                                       CAS: 10028-15-6      
                                                    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                                          OZONE                                         DATE: 05/08/95       
EXPERIMENT: 88034 TEST: 04                                                                                     TIME: 20:53:20       
TEST TYPE:  CHRONIC                             CAGES FROM 0000 TO LAST CAGE                                                        
CONT: N01-ES-95239          ROUTE: RESPIRATORY EXPOSURE WHOLE BODY                                             NTP C#: C88034       
PATHOLOGIST: S. GRUMBEIN                                                                                       CAS: 10028-15-6      
                                     SUMMARY OF STATISTICALLY SIGNIFICANT (P<=.05) RESULTS
                                            IN THE ANALYSIS OF THE STUDY OF 6  OZONE
              ====================================================================================================
                                                           MALE MICE
                                                          -------------
                  ORGAN                               MORPHOLOGY
                 -------                             ------------
              Harderian Gland               Carcinoma or Adenoma
              Liver                         Hepatocellular Carcinoma
              Lung                          Alveolar/Bronchiolar Adenoma
                                            Alveolar/Bronchiolar Carcinoma or Alveolar/Bronchiolar Adenoma
              All Organs                    Hemangiosarcoma
                                            Hemangiosarcoma or Hemangioma
              ====================================================================================================
                                                           FEMALE MICE
                                                          -------------
                  ORGAN                               MORPHOLOGY
                 -------                             ------------
              Liver                         Hepatocellular Adenoma
                                            Hepatocellular Carcinoma
                                            Hepatocellular Carcinoma or Hepatocellular Adenoma
                                            Hepatocellular Carcinoma, Hepatocellular Adenoma, or Hepatoblastoma
              Lung                          Alveolar/Bronchiolar Carcinoma
                                            Alveolar/Bronchiolar Carcinoma or Alveolar/Bronchiolar Adenoma
              Pituitary Gland: Pars Distalis or Unspecified Site
                                            Adenoma
              Uterus                        Polyp Stromal
              All Organs                    Malignant Lymphoma And Histiocytic Sarcoma
                                            Malignant Lymphoma: Histiocytic, Lymphocytic, Mixed, NOS, or Undifferentiated
                                             Cell Type
                                            Benign Tumors
                                            Malignant and Benign Tumors
              ====================================================================================================
         DATE: 05/08/95                     EXPERIMENT: 88034 TEST: 04                                                 PAGE   1
                                  STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- 6  OZONE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      0.12 PPM     0.5 PPM      1.0 PPM   |   CONTROL      0.12 PPM     0.5 PPM      1.0 PPM   |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Adrenal Medulla                                                                                                                  |
|     Pheochromocytoma Benign                                                                                                     |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  0/50 (0%)    0/50 (0%)    0/50 (0%)    1/50 (2%)  |  2/50 (4%)    2/50 (4%)    3/49 (6%)    0/50 (0%)  |
|ADJUSTED (b)           |   0.0%         0.0%         0.0%         3.7%      |   6.9%         5.4%         8.5%         0.0%      |
|TERMINAL (d)           |  0/30 (0%)    0/34 (0%)    0/25 (0%)    1/27 (4%)  |  2/29 (7%)    2/37 (5%)    2/33 (6%)    0/40 (0%)  |
|FIRST INCIDENCE (DAYS) |   ---          ---          ---          733 (T)   |   735 (T)      735 (T)      693          ---       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.167        (e)          (e)        P=0.479    |  P=0.152N     P=0.605N     P=0.559      P=0.171N   |
|INCIDENTAL TUMOR       |  P=0.167        (e)          (e)        P=0.479    |  P=0.179N     P=0.605N     P=0.538      P=0.171N   |
|LOGISTIC REGRESSION    |  P=0.167        (e)          (e)        P=0.479    |  P=0.175N     P=0.605N     P=0.541      P=0.171N   |
|COCHRAN-ARMITAGE       |  P=0.188                                           |  P=0.204N                                          |
|FISHER EXACT           |                 (e)          (e)        P=0.500    |               P=0.691N     P=0.490      P=0.247N   |
|=================================================================================================================================|
|                                                                                                                                 |
|Adrenal Medulla                                                                                                                  |
|     Pheochromocytoma: Benign, Complex, Malignant, NOS                                                                           |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  0/50 (0%)    1/50 (2%)    0/50 (0%)    1/50 (2%)  |  2/50 (4%)    2/50 (4%)    3/49 (6%)    0/50 (0%)  |
|ADJUSTED (b)           |   0.0%         2.4%         0.0%         3.7%      |   6.9%         5.4%         8.5%         0.0%      |
|TERMINAL (d)           |  0/30 (0%)    0/34 (0%)    0/25 (0%)    1/27 (4%)  |  2/29 (7%)    2/37 (5%)    2/33 (6%)    0/40 (0%)  |
|FIRST INCIDENCE (DAYS) |   ---          612          ---          733 (T)   |   735 (T)      735 (T)      693          ---       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.419      P=0.510        (e)        P=0.479    |  P=0.152N     P=0.605N     P=0.559      P=0.171N   |
|INCIDENTAL TUMOR       |  P=0.476      P=0.443        (e)        P=0.479    |  P=0.179N     P=0.605N     P=0.538      P=0.171N   |
|LOGISTIC REGRESSION    |  P=0.449      P=0.464        (e)        P=0.479    |  P=0.175N     P=0.605N     P=0.541      P=0.171N   |
|COCHRAN-ARMITAGE       |  P=0.456                                           |  P=0.204N                                          |
|FISHER EXACT           |               P=0.500        (e)        P=0.500    |               P=0.691N     P=0.490      P=0.247N   |
|=================================================================================================================================|
         DATE: 05/08/95                     EXPERIMENT: 88034 TEST: 04                                                 PAGE   2
                                  STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- 6  OZONE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      0.12 PPM     0.5 PPM      1.0 PPM   |   CONTROL      0.12 PPM     0.5 PPM      1.0 PPM   |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Bone Marrow                                                                                                                      |
|     Hemangiosarcoma                                                                                                             |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  0/49 (0%)    0/50 (0%)    0/50 (0%)    0/50 (0%)  |  1/50 (2%)    0/50 (0%)    3/49 (6%)    1/50 (2%)  |
|ADJUSTED (b)           |   0.0%         0.0%         0.0%         0.0%      |   3.3%         0.0%         8.4%         2.5%      |
|TERMINAL (d)           |  0/30 (0%)    0/34 (0%)    0/25 (0%)    0/27 (0%)  |  0/29 (0%)    0/37 (0%)    2/33 (6%)    1/40 (3%)  |
|FIRST INCIDENCE (DAYS) |   ---          ---          ---          ---       |   728          ---          677          735 (T)   |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |    (e)          (e)          (e)          (e)      |  P=0.463      P=0.458N     P=0.354      P=0.691N   |
|INCIDENTAL TUMOR       |    (e)          (e)          (e)          (e)      |  P=0.327      P=0.590N     P=0.311      P=0.677    |
|LOGISTIC REGRESSION    |    (e)          (e)          (e)          (e)      |  P=0.414      P=0.473N     P=0.322      P=0.723N   |
|COCHRAN-ARMITAGE       |    (e)                                             |  P=0.396                                           |
|FISHER EXACT           |                 (e)          (e)          (e)      |               P=0.500N     P=0.301      P=0.753N   |
|=================================================================================================================================|
|                                                                                                                                 |
|Harderian Gland                                                                                                                  |
|     Adenoma                                                                                                                     |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  1/50 (2%)    4/50 (8%)    3/50 (6%)    4/50 (8%)  |  1/50 (2%)    0/50 (0%)    3/50 (6%)    1/50 (2%)  |
|ADJUSTED (b)           |   2.0%        11.8%         9.7%        13.1%      |   3.4%         0.0%         8.0%         2.5%      |
|TERMINAL (d)           |  0/30 (0%)    4/34 (12%)   1/25 (4%)    3/27 (11%) |  1/29 (3%)    0/37 (0%)    2/33 (6%)    1/40 (3%)  |
|FIRST INCIDENCE (DAYS) |   362          733 (T)      621          506       |   735 (T)      ---          527          735 (T)   |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.183      P=0.213      P=0.268      P=0.162    |  P=0.456      P=0.451N     P=0.341      P=0.688N   |
|INCIDENTAL TUMOR       |  P=0.270      P=0.079      P=0.250      P=0.195    |  P=0.478      P=0.451N     P=0.261      P=0.688N   |
|LOGISTIC REGRESSION    |  P=0.246      P=0.164      P=0.335      P=0.199    |  P=0.395      P=0.451N     P=0.303      P=0.688N   |
|COCHRAN-ARMITAGE       |  P=0.253                                           |  P=0.397                                           |
|FISHER EXACT           |               P=0.181      P=0.309      P=0.181    |               P=0.500N     P=0.309      P=0.753N   |
|=================================================================================================================================|
         DATE: 05/08/95                     EXPERIMENT: 88034 TEST: 04                                                 PAGE   3
                                  STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- 6  OZONE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      0.12 PPM     0.5 PPM      1.0 PPM   |   CONTROL      0.12 PPM     0.5 PPM      1.0 PPM   |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Harderian Gland                                                                                                                  |
|     Carcinoma                                                                                                                   |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  0/50 (0%)    3/50 (6%)    3/50 (6%)    0/50 (0%)  |  2/50 (4%)    2/50 (4%)    1/50 (2%)    2/50 (4%)  |
|ADJUSTED (b)           |   0.0%         8.8%        10.5%         0.0%      |   4.8%         5.4%         2.3%         4.5%      |
|TERMINAL (d)           |  0/30 (0%)    3/34 (9%)    1/25 (4%)    0/27 (0%)  |  0/29 (0%)    2/37 (5%)    0/33 (0%)    1/40 (3%)  |
|FIRST INCIDENCE (DAYS) |   ---          733 (T)      659          ---       |   538          735 (T)      659          488       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.444N     P=0.143      P=0.095        (e)      |  P=0.513N     P=0.630N     P=0.477N     P=0.651N   |
|INCIDENTAL TUMOR       |  P=0.449N     P=0.143      P=0.106        (e)      |  P=0.578N     P=0.621      P=0.602N     P=0.625    |
|LOGISTIC REGRESSION    |  P=0.425N     P=0.143      P=0.107        (e)      |  P=0.564N     P=0.668      P=0.478N     P=0.665    |
|COCHRAN-ARMITAGE       |  P=0.367N                                          |  P=0.561N                                          |
|FISHER EXACT           |               P=0.121      P=0.121        (e)      |               P=0.691N     P=0.500N     P=0.691N   |
|=================================================================================================================================|
|                                                                                                                                 |
|Harderian Gland                                                                                                                  |
|     Carcinoma or Adenoma                                                                                                        |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  1/50 (2%)    7/50 (14%)   6/50 (12%)   4/50 (8%)  |  3/50 (6%)    2/50 (4%)    4/50 (8%)    3/50 (6%)  |
|ADJUSTED (b)           |   2.0%        20.6%        19.4%        13.1%      |   8.1%         5.4%        10.2%         6.9%      |
|TERMINAL (d)           |  0/30 (0%)    7/34 (21%)   2/25 (8%)    3/27 (11%) |  1/29 (3%)    2/37 (5%)    2/33 (6%)    2/40 (5%)  |
|FIRST INCIDENCE (DAYS) |   362          733 (T)      621          506       |   538          735 (T)      527          488       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.306      P=0.046 *    P=0.044 *    P=0.162    |  P=0.535      P=0.417N     P=0.545      P=0.575N   |
|INCIDENTAL TUMOR       |  P=0.388      P=0.013 *    P=0.043 *    P=0.195    |  P=0.500      P=0.553N     P=0.395      P=0.653    |
|LOGISTIC REGRESSION    |  P=0.384      P=0.034 *    P=0.064      P=0.199    |  P=0.454      P=0.520N     P=0.504      P=0.632    |
|COCHRAN-ARMITAGE       |  P=0.425                                           |  P=0.460                                           |
|FISHER EXACT           |               P=0.030 *    P=0.056      P=0.181    |               P=0.500N     P=0.500      P=0.661N   |
|=================================================================================================================================|
         DATE: 05/08/95                     EXPERIMENT: 88034 TEST: 04                                                 PAGE   4
                                  STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- 6  OZONE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      0.12 PPM     0.5 PPM      1.0 PPM   |   CONTROL      0.12 PPM     0.5 PPM      1.0 PPM   |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Islets, Pancreatic                                                                                                               |
|     Adenoma                                                                                                                     |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  0/49 (0%)    2/50 (4%)    0/49 (0%)    1/50 (2%)  |  0/49 (0%)    0/50 (0%)    1/48 (2%)    0/50 (0%)  |
|ADJUSTED (b)           |   0.0%         5.4%         0.0%         3.6%      |   0.0%         0.0%         3.0%         0.0%      |
|TERMINAL (d)           |  0/30 (0%)    1/34 (3%)    0/25 (0%)    0/27 (0%)  |  0/29 (0%)    0/37 (0%)    1/33 (3%)    0/40 (0%)  |
|FIRST INCIDENCE (DAYS) |   ---          667          ---          709       |   ---          ---          735 (T)      ---       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.576      P=0.266        (e)        P=0.480    |  P=0.682        (e)        P=0.526        (e)      |
|INCIDENTAL TUMOR       |  P=0.568      P=0.233        (e)        P=0.419    |  P=0.682        (e)        P=0.526        (e)      |
|LOGISTIC REGRESSION    |  P=0.600      P=0.247        (e)        P=0.479    |  P=0.682        (e)        P=0.526        (e)      |
|COCHRAN-ARMITAGE       |  P=0.634                                           |  P=0.655                                           |
|FISHER EXACT           |               P=0.253        (e)        P=0.505    |                 (e)        P=0.495        (e)      |
|=================================================================================================================================|
|                                                                                                                                 |
|Islets, Pancreatic                                                                                                               |
|     Carcinoma or Adenoma                                                                                                        |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  0/49 (0%)    2/50 (4%)    0/49 (0%)    1/50 (2%)  |  0/49 (0%)    0/50 (0%)    1/48 (2%)    1/50 (2%)  |
|ADJUSTED (b)           |   0.0%         5.4%         0.0%         3.6%      |   0.0%         0.0%         3.0%         2.5%      |
|TERMINAL (d)           |  0/30 (0%)    1/34 (3%)    0/25 (0%)    0/27 (0%)  |  0/29 (0%)    0/37 (0%)    1/33 (3%)    1/40 (3%)  |
|FIRST INCIDENCE (DAYS) |   ---          667          ---          709       |   ---          ---          735 (T)      735 (T)   |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.576      P=0.266        (e)        P=0.480    |  P=0.253        (e)        P=0.526      P=0.564    |
|INCIDENTAL TUMOR       |  P=0.568      P=0.233        (e)        P=0.419    |  P=0.253        (e)        P=0.526      P=0.564    |
|LOGISTIC REGRESSION    |  P=0.600      P=0.247        (e)        P=0.479    |  P=0.253        (e)        P=0.526      P=0.564    |
|COCHRAN-ARMITAGE       |  P=0.634                                           |  P=0.214                                           |
|FISHER EXACT           |               P=0.253        (e)        P=0.505    |                 (e)        P=0.495      P=0.505    |
|=================================================================================================================================|
         DATE: 05/08/95                     EXPERIMENT: 88034 TEST: 04                                                 PAGE   5
                                  STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- 6  OZONE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      0.12 PPM     0.5 PPM      1.0 PPM   |   CONTROL      0.12 PPM     0.5 PPM      1.0 PPM   |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Kidney: Renal Tubule                                                                                                             |
|     Carcinoma or Adenoma                                                                                                        |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  2/50 (4%)    1/50 (2%)    0/50 (0%)    0/50 (0%)  |  0/50 (0%)    0/50 (0%)    0/49 (0%)    0/50 (0%)  |
|ADJUSTED (b)           |   5.5%         2.9%         0.0%         0.0%      |   0.0%         0.0%         0.0%         0.0%      |
|TERMINAL (d)           |  1/30 (3%)    1/34 (3%)    0/25 (0%)    0/27 (0%)  |  0/29 (0%)    0/37 (0%)    0/33 (0%)    0/40 (0%)  |
|FIRST INCIDENCE (DAYS) |   596          733 (T)      ---          ---       |   ---          ---          ---          ---       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.129N     P=0.474N     P=0.283N     P=0.274N   |    (e)          (e)          (e)          (e)      |
|INCIDENTAL TUMOR       |  P=0.107N     P=0.504N     P=0.246N     P=0.226N   |    (e)          (e)          (e)          (e)      |
|LOGISTIC REGRESSION    |  P=0.111N     P=0.495N     P=0.239N     P=0.239N   |    (e)          (e)          (e)          (e)      |
|COCHRAN-ARMITAGE       |  P=0.104N                                          |    (e)                                             |
|FISHER EXACT           |               P=0.500N     P=0.247N     P=0.247N   |                 (e)          (e)          (e)      |
|=================================================================================================================================|
|                                                                                                                                 |
|Liver                                                                                                                            |
|     Hemangiosarcoma                                                                                                             |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  0/50 (0%)    3/50 (6%)    1/50 (2%)    0/50 (0%)  |  0/50 (0%)    0/50 (0%)    1/50 (2%)    0/50 (0%)  |
|ADJUSTED (b)           |   0.0%         7.2%         3.3%         0.0%      |   0.0%         0.0%         3.0%         0.0%      |
|TERMINAL (d)           |  0/30 (0%)    1/34 (3%)    0/25 (0%)    0/27 (0%)  |  0/29 (0%)    0/37 (0%)    1/33 (3%)    0/40 (0%)  |
|FIRST INCIDENCE (DAYS) |   ---          540          659          ---       |   ---          ---          735 (T)      ---       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.303N     P=0.134      P=0.469        (e)      |  P=0.682        (e)        P=0.526        (e)      |
|INCIDENTAL TUMOR       |  P=0.227N     P=0.126      P=0.500        (e)      |  P=0.682        (e)        P=0.526        (e)      |
|LOGISTIC REGRESSION    |  P=0.231N     P=0.091      P=0.500        (e)      |  P=0.682        (e)        P=0.526        (e)      |
|COCHRAN-ARMITAGE       |  P=0.254N                                          |  P=0.655                                           |
|FISHER EXACT           |               P=0.121      P=0.500        (e)      |                 (e)        P=0.500        (e)      |
|=================================================================================================================================|
         DATE: 05/08/95                     EXPERIMENT: 88034 TEST: 04                                                 PAGE   6
                                  STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- 6  OZONE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      0.12 PPM     0.5 PPM      1.0 PPM   |   CONTROL      0.12 PPM     0.5 PPM      1.0 PPM   |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Liver                                                                                                                            |
|     Hepatocellular Adenoma                                                                                                      |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            | 23/50 (46%)  21/50 (42%)  19/50 (38%)  16/50 (32%) | 20/50 (40%)  18/50 (36%)  17/50 (34%)   8/50 (16%) |
|ADJUSTED (b)           |  65.0%        53.6%        59.5%        43.3%      |  59.9%        48.6%        43.2%        18.6%      |
|TERMINAL (d)           | 18/30 (60%)  16/34 (47%)  13/25 (52%)   8/27 (30%) | 16/29 (55%)  18/37 (49%)  12/33 (36%)   6/40 (15%) |
|FIRST INCIDENCE (DAYS) |   446          545          484          462       |   538          735 (T)      488          516       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.293N     P=0.250N     P=0.541N     P=0.229N   |  P<0.001N**   P=0.118N     P=0.200N     P<0.001N** |
|INCIDENTAL TUMOR       |  P=0.143N     P=0.305N     P=0.369N     P=0.122N   |  P=0.001N**   P=0.183N     P=0.321N     P=0.002N** |
|LOGISTIC REGRESSION    |  P=0.159N     P=0.333N     P=0.401N     P=0.148N   |  P=0.004N**   P=0.231N     P=0.297N     P=0.005N** |
|COCHRAN-ARMITAGE       |  P=0.084N                                          |  P=0.005N**                                        |
|FISHER EXACT           |               P=0.420N     P=0.272N     P=0.109N   |               P=0.418N     P=0.339N     P=0.007N** |
|=================================================================================================================================|
|                                                                                                                                 |
|Liver                                                                                                                            |
|     Hepatocellular Carcinoma                                                                                                    |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            | 12/50 (24%)   6/50 (12%)  13/50 (26%)  15/50 (30%) | 15/50 (30%)   5/50 (10%)   5/50 (10%)   3/50 (6%)  |
|ADJUSTED (b)           |  29.2%        13.1%        31.8%        38.5%      |  39.5%        11.4%        12.5%         7.3%      |
|TERMINAL (d)           |  4/30 (13%)   1/34 (3%)    2/25 (8%)    5/27 (19%) |  7/29 (24%)   1/37 (3%)    2/33 (6%)    2/40 (5%)  |
|FIRST INCIDENCE (DAYS) |   362          440          460          350       |   566          567          644          685       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.047 *    P=0.091N     P=0.391      P=0.258    |  P=0.003N**   P=0.007N**   P=0.010N**   P<0.001N** |
|INCIDENTAL TUMOR       |  P=0.145      P=0.128N     P=0.422N     P=0.352    |  P=0.018N*    P=0.020N*    P=0.009N**   P=0.013N*  |
|LOGISTIC REGRESSION    |  P=0.188      P=0.100N     P=0.469N     P=0.392    |  P=0.014N*    P=0.018N*    P=0.011N*    P=0.002N** |
|COCHRAN-ARMITAGE       |  P=0.075                                           |  P=0.005N**                                        |
|FISHER EXACT           |               P=0.096N     P=0.500      P=0.326    |               P=0.011N*    P=0.011N*    P=0.002N** |
|=================================================================================================================================|
         DATE: 05/08/95                     EXPERIMENT: 88034 TEST: 04                                                 PAGE   7
                                  STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- 6  OZONE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      0.12 PPM     0.5 PPM      1.0 PPM   |   CONTROL      0.12 PPM     0.5 PPM      1.0 PPM   |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Liver                                                                                                                            |
|     Hepatocellular Carcinoma or Hepatocellular Adenoma                                                                          |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            | 30/50 (60%)  27/50 (54%)  29/50 (58%)  29/50 (58%) | 27/50 (54%)  22/50 (44%)  20/50 (40%)  11/50 (22%) |
|ADJUSTED (b)           |  70.7%        60.7%        70.8%        66.9%      |  68.6%        53.2%        48.5%        25.2%      |
|TERMINAL (d)           | 18/30 (60%)  17/34 (50%)  14/25 (56%)  13/27 (48%) | 17/29 (59%)  18/37 (49%)  13/33 (39%)   8/40 (20%) |
|FIRST INCIDENCE (DAYS) |   362          440          460          350       |   538          567          488          516       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.206      P=0.218N     P=0.362      P=0.434    |  P<0.001N**   P=0.049N*    P=0.064N     P<0.001N** |
|INCIDENTAL TUMOR       |  P=0.522      P=0.313N     P=0.389N     P=0.521N   |  P=0.001N**   P=0.141N     P=0.112N     P=0.002N** |
|LOGISTIC REGRESSION    |  P=0.517      P=0.356N     P=0.506N     P=0.512N   |  P<0.001N**   P=0.141N     P=0.103N     P<0.001N** |
|COCHRAN-ARMITAGE       |  P=0.512                                           |  P<0.001N**                                        |
|FISHER EXACT           |               P=0.343N     P=0.500N     P=0.500N   |               P=0.212N     P=0.115N     P<0.001N** |
|=================================================================================================================================|
|                                                                                                                                 |
|Liver                                                                                                                            |
|     Hepatocellular Carcinoma, Hepatocellular Adenoma, or Hepatoblastoma                                                         |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            | 30/50 (60%)  27/50 (54%)  29/50 (58%)  29/50 (58%) | 27/50 (54%)  22/50 (44%)  20/50 (40%)  11/50 (22%) |
|ADJUSTED (b)           |  70.7%        60.7%        70.8%        66.9%      |  68.6%        53.2%        48.5%        25.2%      |
|TERMINAL (d)           | 18/30 (60%)  17/34 (50%)  14/25 (56%)  13/27 (48%) | 17/29 (59%)  18/37 (49%)  13/33 (39%)   8/40 (20%) |
|FIRST INCIDENCE (DAYS) |   362          440          460          350       |   538          567          488          516       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.206      P=0.218N     P=0.362      P=0.434    |  P<0.001N**   P=0.049N*    P=0.064N     P<0.001N** |
|INCIDENTAL TUMOR       |  P=0.522      P=0.313N     P=0.389N     P=0.521N   |  P=0.001N**   P=0.141N     P=0.112N     P=0.002N** |
|LOGISTIC REGRESSION    |  P=0.517      P=0.356N     P=0.506N     P=0.512N   |  P<0.001N**   P=0.141N     P=0.103N     P<0.001N** |
|COCHRAN-ARMITAGE       |  P=0.512                                           |  P<0.001N**                                        |
|FISHER EXACT           |               P=0.343N     P=0.500N     P=0.500N   |               P=0.212N     P=0.115N     P<0.001N** |
|=================================================================================================================================|
         DATE: 05/08/95                     EXPERIMENT: 88034 TEST: 04                                                 PAGE   8
                                  STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- 6  OZONE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      0.12 PPM     0.5 PPM      1.0 PPM   |   CONTROL      0.12 PPM     0.5 PPM      1.0 PPM   |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Lung                                                                                                                             |
|     Alveolar/Bronchiolar Adenoma                                                                                                |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  6/50 (12%)   9/50 (18%)  12/50 (24%)  11/50 (22%) |  4/50 (8%)    5/50 (10%)   5/49 (10%)   8/50 (16%) |
|ADJUSTED (b)           |  18.8%        25.1%        40.9%        34.7%      |  12.5%        12.9%        13.4%        20.0%      |
|TERMINAL (d)           |  5/30 (17%)   8/34 (24%)   9/25 (36%)   8/27 (30%) |  3/29 (10%)   4/37 (11%)   2/33 (6%)    8/40 (20%) |
|FIRST INCIDENCE (DAYS) |   611          440          464          484       |   636          681          667          735 (T)   |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.053      P=0.372      P=0.045 *    P=0.100    |  P=0.233      P=0.631      P=0.573      P=0.349    |
|INCIDENTAL TUMOR       |  P=0.086      P=0.365      P=0.063      P=0.145    |  P=0.122      P=0.571      P=0.490      P=0.298    |
|LOGISTIC REGRESSION    |  P=0.079      P=0.318      P=0.061      P=0.110    |  P=0.153      P=0.549      P=0.515      P=0.239    |
|COCHRAN-ARMITAGE       |  P=0.130                                           |  P=0.130                                           |
|FISHER EXACT           |               P=0.288      P=0.096      P=0.143    |               P=0.500      P=0.487      P=0.178    |
|=================================================================================================================================|
|                                                                                                                                 |
|Lung                                                                                                                             |
|     Alveolar/Bronchiolar Carcinoma                                                                                              |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  8/50 (16%)   4/50 (8%)    8/50 (16%)  10/50 (20%) |  2/50 (4%)    2/50 (4%)    5/49 (10%)   8/50 (16%) |
|ADJUSTED (b)           |  25.5%        10.3%        30.7%        35.4%      |   6.9%         5.2%        14.1%        19.2%      |
|TERMINAL (d)           |  7/30 (23%)   1/34 (3%)    7/25 (28%)   9/27 (33%) |  2/29 (7%)    1/37 (3%)    3/33 (9%)    7/40 (18%) |
|FIRST INCIDENCE (DAYS) |   653          612          701          630       |   735 (T)      703          709          488       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.063      P=0.135N     P=0.451      P=0.294    |  P=0.025 *    P=0.608N     P=0.275      P=0.114    |
|INCIDENTAL TUMOR       |  P=0.068      P=0.170N     P=0.469      P=0.300    |  P=0.012 *    P=0.670N     P=0.244      P=0.114    |
|LOGISTIC REGRESSION    |  P=0.062      P=0.154N     P=0.449      P=0.270    |  P=0.011 *    P=0.649N     P=0.259      P=0.053    |
|COCHRAN-ARMITAGE       |  P=0.145                                           |  P=0.010 **                                        |
|FISHER EXACT           |               P=0.178N     P=0.607N     P=0.398    |               P=0.691N     P=0.210      P=0.046 *  |
|=================================================================================================================================|
         DATE: 05/08/95                     EXPERIMENT: 88034 TEST: 04                                                 PAGE   9
                                  STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- 6  OZONE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      0.12 PPM     0.5 PPM      1.0 PPM   |   CONTROL      0.12 PPM     0.5 PPM      1.0 PPM   |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Lung                                                                                                                             |
|     Alveolar/Bronchiolar Carcinoma or Alveolar/Bronchiolar Adenoma                                                              |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            | 14/50 (28%)  13/50 (26%)  18/50 (36%)  19/50 (38%) |  6/50 (12%)   7/50 (14%)   9/49 (18%)  16/50 (32%) |
|ADJUSTED (b)           |  43.1%        33.4%        60.9%        60.0%      |  19.2%        17.7%        24.0%        38.8%      |
|TERMINAL (d)           | 12/30 (40%)   9/34 (26%)  14/25 (56%)  15/27 (56%) |  5/29 (17%)   5/37 (14%)   5/33 (15%)  15/40 (38%) |
|FIRST INCIDENCE (DAYS) |   611          440          464          484       |   636          681          667          488       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.020 *    P=0.368N     P=0.099      P=0.103    |  P=0.020 *    P=0.568N     P=0.386      P=0.074    |
|INCIDENTAL TUMOR       |  P=0.034 *    P=0.422N     P=0.133      P=0.142    |  P=0.005 **   P=0.578      P=0.308      P=0.059    |
|LOGISTIC REGRESSION    |  P=0.030 *    P=0.445N     P=0.124      P=0.103    |  P=0.005 **   P=0.571      P=0.326      P=0.022 *  |
|COCHRAN-ARMITAGE       |  P=0.094                                           |  P=0.004 **                                        |
|FISHER EXACT           |               P=0.500N     P=0.260      P=0.198    |               P=0.500      P=0.274      P=0.014 *  |
|=================================================================================================================================|
|                                                                                                                                 |
|Ovary                                                                                                                            |
|     Cystadenoma                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |                                                    |  1/50 (2%)    2/50 (4%)    2/48 (4%)    1/50 (2%)  |
|ADJUSTED (b)           |                                                    |   3.4%         5.1%         5.3%         2.4%      |
|TERMINAL (d)           |                                                    |  1/29 (3%)    1/37 (3%)    1/33 (3%)    0/40 (0%)  |
|FIRST INCIDENCE (DAYS) |                                                    |   735 (T)      687          667          685       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |                                                    |  P=0.465N     P=0.572      P=0.541      P=0.704N   |
|INCIDENTAL TUMOR       |                                                    |  P=0.573      P=0.505      P=0.507      P=0.677    |
|LOGISTIC REGRESSION    |                                                    |  P=0.524N     P=0.529      P=0.501      P=0.755N   |
|COCHRAN-ARMITAGE       |                                                    |  P=0.528N                                          |
|FISHER EXACT           |                                                    |               P=0.500      P=0.485      P=0.753N   |
|=================================================================================================================================|
         DATE: 05/08/95                     EXPERIMENT: 88034 TEST: 04                                                 PAGE  10
                                  STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- 6  OZONE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      0.12 PPM     0.5 PPM      1.0 PPM   |   CONTROL      0.12 PPM     0.5 PPM      1.0 PPM   |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Ovary                                                                                                                            |
|     Granulosa Cell Tumor: Benign, Malignant, NOS                                                                                |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |                                                    |  0/50 (0%)    2/50 (4%)    0/48 (0%)    0/50 (0%)  |
|ADJUSTED (b)           |                                                    |   0.0%         5.4%         0.0%         0.0%      |
|TERMINAL (d)           |                                                    |  0/29 (0%)    2/37 (5%)    0/33 (0%)    0/40 (0%)  |
|FIRST INCIDENCE (DAYS) |                                                    |   ---          735 (T)      ---          ---       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |                                                    |  P=0.245N     P=0.293        (e)          (e)      |
|INCIDENTAL TUMOR       |                                                    |  P=0.245N     P=0.293        (e)          (e)      |
|LOGISTIC REGRESSION    |                                                    |  P=0.245N     P=0.293        (e)          (e)      |
|COCHRAN-ARMITAGE       |                                                    |  P=0.282N                                          |
|FISHER EXACT           |                                                    |               P=0.247        (e)          (e)      |
|=================================================================================================================================|
|                                                                                                                                 |
|Pituitary Gland: Pars Distalis or Unspecified Site                                                                               |
|     Adenoma                                                                                                                     |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  0/47 (0%)    0/49 (0%)    0/49 (0%)    0/48 (0%)  | 17/50 (34%)  13/50 (26%)  14/47 (30%)   9/49 (18%) |
|ADJUSTED (b)           |   0.0%         0.0%         0.0%         0.0%      |  48.7%        32.1%        40.1%        22.1%      |
|TERMINAL (d)           |  0/29 (0%)    0/34 (0%)    0/25 (0%)    0/27 (0%)  | 12/29 (41%)  10/37 (27%)  11/31 (35%)   8/39 (21%) |
|FIRST INCIDENCE (DAYS) |   ---          ---          ---          ---       |   511          653          644          488       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |    (e)          (e)          (e)          (e)      |  P=0.025N*    P=0.098N     P=0.254N     P=0.011N*  |
|INCIDENTAL TUMOR       |    (e)          (e)          (e)          (e)      |  P=0.062N     P=0.201N     P=0.363N     P=0.034N*  |
|LOGISTIC REGRESSION    |    (e)          (e)          (e)          (e)      |  P=0.067N     P=0.193N     P=0.345N     P=0.050N*  |
|COCHRAN-ARMITAGE       |    (e)                                             |  P=0.080N                                          |
|FISHER EXACT           |                 (e)          (e)          (e)      |               P=0.257N     P=0.411N     P=0.061N   |
|=================================================================================================================================|
         DATE: 05/08/95                     EXPERIMENT: 88034 TEST: 04                                                 PAGE  11
                                  STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- 6  OZONE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      0.12 PPM     0.5 PPM      1.0 PPM   |   CONTROL      0.12 PPM     0.5 PPM      1.0 PPM   |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Pituitary Gland: Pars Intermedia                                                                                                 |
|     Adenoma                                                                                                                     |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  1/47 (2%)    0/49 (0%)    0/49 (0%)    0/48 (0%)  |  0/50 (0%)    3/50 (6%)    2/47 (4%)    2/49 (4%)  |
|ADJUSTED (b)           |   2.5%         0.0%         0.0%         0.0%      |   0.0%         8.1%         5.6%         5.1%      |
|TERMINAL (d)           |  0/29 (0%)    0/34 (0%)    0/25 (0%)    0/27 (0%)  |  0/29 (0%)    3/37 (8%)    1/31 (3%)    2/39 (5%)  |
|FIRST INCIDENCE (DAYS) |   611          ---          ---          ---       |   ---          735 (T)      677          735 (T)   |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.369N     P=0.495N     P=0.532N     P=0.527N   |  P=0.465      P=0.167      P=0.262      P=0.306    |
|INCIDENTAL TUMOR       |  P=0.298N     P=0.531N     P=0.450N     P=0.450N   |  P=0.412      P=0.167      P=0.236      P=0.306    |
|LOGISTIC REGRESSION    |  P=0.319N     P=0.525N     P=0.476N     P=0.478N   |  P=0.412      P=0.167      P=0.228      P=0.306    |
|COCHRAN-ARMITAGE       |  P=0.344N                                          |  P=0.382                                           |
|FISHER EXACT           |               P=0.490N     P=0.490N     P=0.495N   |               P=0.121      P=0.232      P=0.242    |
|=================================================================================================================================|
|                                                                                                                                 |
|Spleen                                                                                                                           |
|     Hemangiosarcoma                                                                                                             |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  0/49 (0%)    1/50 (2%)    1/49 (2%)    0/50 (0%)  |  1/49 (2%)    1/50 (2%)    4/48 (8%)    2/50 (4%)  |
|ADJUSTED (b)           |   0.0%         2.9%         3.3%         0.0%      |   3.3%         2.7%        11.3%         5.0%      |
|TERMINAL (d)           |  0/30 (0%)    0/34 (0%)    0/25 (0%)    0/27 (0%)  |  0/29 (0%)    1/37 (3%)    3/33 (9%)    2/40 (5%)  |
|FIRST INCIDENCE (DAYS) |   ---          699          659          ---       |   728          735 (T)      677          735 (T)   |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.591N     P=0.518      P=0.469        (e)      |  P=0.364      P=0.709N     P=0.224      P=0.607    |
|INCIDENTAL TUMOR       |  P=0.614N     P=0.464      P=0.500        (e)      |  P=0.265      P=0.750      P=0.191      P=0.446    |
|LOGISTIC REGRESSION    |  P=0.553N     P=0.509      P=0.501        (e)      |  P=0.313      P=0.725N     P=0.198      P=0.575    |
|COCHRAN-ARMITAGE       |  P=0.541N                                          |  P=0.284                                           |
|FISHER EXACT           |               P=0.505      P=0.500        (e)      |               P=0.747N     P=0.175      P=0.508    |
|=================================================================================================================================|
         DATE: 05/08/95                     EXPERIMENT: 88034 TEST: 04                                                 PAGE  12
                                  STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- 6  OZONE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      0.12 PPM     0.5 PPM      1.0 PPM   |   CONTROL      0.12 PPM     0.5 PPM      1.0 PPM   |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Stomach, Forestomach                                                                                                             |
|     Squamous Cell Carcinoma or Papilloma Squamous                                                                               |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  0/50 (0%)    3/50 (6%)    0/50 (0%)    0/50 (0%)  |  0/50 (0%)    1/50 (2%)    0/50 (0%)    0/50 (0%)  |
|ADJUSTED (b)           |   0.0%         8.3%         0.0%         0.0%      |   0.0%         2.7%         0.0%         0.0%      |
|TERMINAL (d)           |  0/30 (0%)    2/34 (6%)    0/25 (0%)    0/27 (0%)  |  0/29 (0%)    1/37 (3%)    0/33 (0%)    0/40 (0%)  |
|FIRST INCIDENCE (DAYS) |   ---          667          ---          ---       |   ---          735 (T)      ---          ---       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.224N     P=0.145        (e)          (e)      |  P=0.432N     P=0.549        (e)          (e)      |
|INCIDENTAL TUMOR       |  P=0.222N     P=0.126        (e)          (e)      |  P=0.432N     P=0.549        (e)          (e)      |
|LOGISTIC REGRESSION    |  P=0.210N     P=0.129        (e)          (e)      |  P=0.432N     P=0.549        (e)          (e)      |
|COCHRAN-ARMITAGE       |  P=0.183N                                          |  P=0.464N                                          |
|FISHER EXACT           |               P=0.121        (e)          (e)      |               P=0.500        (e)          (e)      |
|=================================================================================================================================|
|                                                                                                                                 |
|Stomach, Forestomach                                                                                                             |
|     Squamous Cell Papilloma                                                                                                     |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  0/50 (0%)    2/50 (4%)    0/50 (0%)    0/50 (0%)  |  0/50 (0%)    1/50 (2%)    0/50 (0%)    0/50 (0%)  |
|ADJUSTED (b)           |   0.0%         5.4%         0.0%         0.0%      |   0.0%         2.7%         0.0%         0.0%      |
|TERMINAL (d)           |  0/30 (0%)    1/34 (3%)    0/25 (0%)    0/27 (0%)  |  0/29 (0%)    1/37 (3%)    0/33 (0%)    0/40 (0%)  |
|FIRST INCIDENCE (DAYS) |   ---          667          ---          ---       |   ---          735 (T)      ---          ---       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.323N     P=0.266        (e)          (e)      |  P=0.432N     P=0.549        (e)          (e)      |
|INCIDENTAL TUMOR       |  P=0.321N     P=0.233        (e)          (e)      |  P=0.432N     P=0.549        (e)          (e)      |
|LOGISTIC REGRESSION    |  P=0.300N     P=0.245        (e)          (e)      |  P=0.432N     P=0.549        (e)          (e)      |
|COCHRAN-ARMITAGE       |  P=0.280N                                          |  P=0.464N                                          |
|FISHER EXACT           |               P=0.247        (e)          (e)      |               P=0.500        (e)          (e)      |
|=================================================================================================================================|
         DATE: 05/08/95                     EXPERIMENT: 88034 TEST: 04                                                 PAGE  13
                                  STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- 6  OZONE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      0.12 PPM     0.5 PPM      1.0 PPM   |   CONTROL      0.12 PPM     0.5 PPM      1.0 PPM   |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Testes                                                                                                                           |
|     Adenoma                                                                                                                     |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  0/50 (0%)    2/50 (4%)    0/50 (0%)    0/50 (0%)  |                                                    |
|ADJUSTED (b)           |   0.0%         5.9%         0.0%         0.0%      |                                                    |
|TERMINAL (d)           |  0/30 (0%)    2/34 (6%)    0/25 (0%)    0/27 (0%)  |                                                    |
|FIRST INCIDENCE (DAYS) |   ---          733 (T)      ---          ---       |                                                    |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.316N     P=0.266        (e)          (e)      |                                                    |
|INCIDENTAL TUMOR       |  P=0.316N     P=0.266        (e)          (e)      |                                                    |
|LOGISTIC REGRESSION    |  P=0.316N     P=0.266        (e)          (e)      |                                                    |
|COCHRAN-ARMITAGE       |  P=0.280N                                          |                                                    |
|FISHER EXACT           |               P=0.247        (e)          (e)      |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Thyroid Gland: Follicular Cell                                                                                                   |
|     Adenoma                                                                                                                     |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  0/49 (0%)    0/50 (0%)    1/50 (2%)    0/50 (0%)  |  2/50 (4%)    2/50 (4%)    4/49 (8%)    2/50 (4%)  |
|ADJUSTED (b)           |   0.0%         0.0%         4.0%         0.0%      |   6.9%         5.4%        12.1%         5.0%      |
|TERMINAL (d)           |  0/30 (0%)    0/34 (0%)    1/25 (4%)    0/27 (0%)  |  2/29 (7%)    2/37 (5%)    4/33 (12%)   2/40 (5%)  |
|FIRST INCIDENCE (DAYS) |   ---          ---          733 (T)      ---       |   735 (T)      735 (T)      735 (T)      735 (T)   |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.627        (e)        P=0.464        (e)      |  P=0.535N     P=0.605N     P=0.397      P=0.574N   |
|INCIDENTAL TUMOR       |  P=0.627        (e)        P=0.464        (e)      |  P=0.535N     P=0.605N     P=0.397      P=0.574N   |
|LOGISTIC REGRESSION    |  P=0.627        (e)        P=0.464        (e)      |  P=0.535N     P=0.605N     P=0.397      P=0.574N   |
|COCHRAN-ARMITAGE       |  P=0.657                                           |  P=0.518                                           |
|FISHER EXACT           |                 (e)        P=0.505        (e)      |               P=0.691N     P=0.329      P=0.691N   |
|=================================================================================================================================|
         DATE: 05/08/95                     EXPERIMENT: 88034 TEST: 04                                                 PAGE  14
                                  STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- 6  OZONE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      0.12 PPM     0.5 PPM      1.0 PPM   |   CONTROL      0.12 PPM     0.5 PPM      1.0 PPM   |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Thyroid Gland: Follicular Cell                                                                                                   |
|     Carcinoma                                                                                                                   |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  0/49 (0%)    0/50 (0%)    0/50 (0%)    0/50 (0%)  |  3/50 (6%)    0/50 (0%)    0/49 (0%)    0/50 (0%)  |
|ADJUSTED (b)           |   0.0%         0.0%         0.0%         0.0%      |   8.6%         0.0%         0.0%         0.0%      |
|TERMINAL (d)           |  0/30 (0%)    0/34 (0%)    0/25 (0%)    0/27 (0%)  |  1/29 (3%)    0/37 (0%)    0/33 (0%)    0/40 (0%)  |
|FIRST INCIDENCE (DAYS) |   ---          ---          ---          ---       |   531          ---          ---          ---       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |    (e)          (e)          (e)          (e)      |  P=0.067N     P=0.098N     P=0.111N     P=0.092N   |
|INCIDENTAL TUMOR       |    (e)          (e)          (e)          (e)      |  P=0.086N     P=0.188N     P=0.172N     P=0.165N   |
|LOGISTIC REGRESSION    |    (e)          (e)          (e)          (e)      |  P=0.075N     P=0.136N     P=0.123N     P=0.129N   |
|COCHRAN-ARMITAGE       |    (e)                                             |  P=0.076N                                          |
|FISHER EXACT           |                 (e)          (e)          (e)      |               P=0.121N     P=0.125N     P=0.121N   |
|=================================================================================================================================|
|                                                                                                                                 |
|Thyroid Gland: Follicular Cell                                                                                                   |
|     Carcinoma or Adenoma                                                                                                        |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  0/49 (0%)    0/50 (0%)    1/50 (2%)    0/50 (0%)  |  5/50 (10%)   2/50 (4%)    4/49 (8%)    2/50 (4%)  |
|ADJUSTED (b)           |   0.0%         0.0%         4.0%         0.0%      |  15.1%         5.4%        12.1%         5.0%      |
|TERMINAL (d)           |  0/30 (0%)    0/34 (0%)    1/25 (4%)    0/27 (0%)  |  3/29 (10%)   2/37 (5%)    4/33 (12%)   2/40 (5%)  |
|FIRST INCIDENCE (DAYS) |   ---          ---          733 (T)      ---       |   531          735 (T)      735 (T)      735 (T)   |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.627        (e)        P=0.464        (e)      |  P=0.200N     P=0.146N     P=0.431N     P=0.127N   |
|INCIDENTAL TUMOR       |  P=0.627        (e)        P=0.464        (e)      |  P=0.221N     P=0.220N     P=0.503N     P=0.187N   |
|LOGISTIC REGRESSION    |  P=0.627        (e)        P=0.464        (e)      |  P=0.266N     P=0.206N     P=0.488N     P=0.207N   |
|COCHRAN-ARMITAGE       |  P=0.657                                           |  P=0.286N                                          |
|FISHER EXACT           |                 (e)        P=0.505        (e)      |               P=0.218N     P=0.513N     P=0.218N   |
|=================================================================================================================================|
         DATE: 05/08/95                     EXPERIMENT: 88034 TEST: 04                                                 PAGE  15
                                  STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- 6  OZONE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      0.12 PPM     0.5 PPM      1.0 PPM   |   CONTROL      0.12 PPM     0.5 PPM      1.0 PPM   |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Uterus                                                                                                                           |
|     Hemangiosarcoma                                                                                                             |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |                                                    |  0/50 (0%)    0/50 (0%)    2/50 (4%)    2/50 (4%)  |
|ADJUSTED (b)           |                                                    |   0.0%         0.0%         5.4%         5.0%      |
|TERMINAL (d)           |                                                    |  0/29 (0%)    0/37 (0%)    1/33 (3%)    2/40 (5%)  |
|FIRST INCIDENCE (DAYS) |                                                    |   ---          ---          677          735 (T)   |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |                                                    |  P=0.098        (e)        P=0.269      P=0.312    |
|INCIDENTAL TUMOR       |                                                    |  P=0.065        (e)        P=0.254      P=0.312    |
|LOGISTIC REGRESSION    |                                                    |  P=0.076        (e)        P=0.241      P=0.312    |
|COCHRAN-ARMITAGE       |                                                    |  P=0.072                                           |
|FISHER EXACT           |                                                    |                 (e)        P=0.247      P=0.247    |
|=================================================================================================================================|
|                                                                                                                                 |
|Uterus                                                                                                                           |
|     Polyp Stromal                                                                                                               |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |                                                    |  1/50 (2%)    0/50 (0%)    0/50 (0%)    5/50 (10%) |
|ADJUSTED (b)           |                                                    |   3.4%         0.0%         0.0%        11.4%      |
|TERMINAL (d)           |                                                    |  1/29 (3%)    0/37 (0%)    0/33 (0%)    3/40 (8%)  |
|FIRST INCIDENCE (DAYS) |                                                    |   735 (T)      ---          ---          482       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |                                                    |  P=0.012 *    P=0.451N     P=0.474N     P=0.164    |
|INCIDENTAL TUMOR       |                                                    |  P=0.010 **   P=0.451N     P=0.474N     P=0.118    |
|LOGISTIC REGRESSION    |                                                    |  P=0.006 **   P=0.451N     P=0.474N     P=0.092    |
|COCHRAN-ARMITAGE       |                                                    |  P=0.007 **                                        |
|FISHER EXACT           |                                                    |               P=0.500N     P=0.500N     P=0.102    |
|=================================================================================================================================|
         DATE: 05/08/95                     EXPERIMENT: 88034 TEST: 04                                                 PAGE  16
                                  STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- 6  OZONE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      0.12 PPM     0.5 PPM      1.0 PPM   |   CONTROL      0.12 PPM     0.5 PPM      1.0 PPM   |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Uterus                                                                                                                           |
|     Sarcoma Stromal                                                                                                             |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |                                                    |  2/50 (4%)    0/50 (0%)    0/50 (0%)    0/50 (0%)  |
|ADJUSTED (b)           |                                                    |   5.0%         0.0%         0.0%         0.0%      |
|TERMINAL (d)           |                                                    |  0/29 (0%)    0/37 (0%)    0/33 (0%)    0/40 (0%)  |
|FIRST INCIDENCE (DAYS) |                                                    |   601          ---          ---          ---       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |                                                    |  P=0.151N     P=0.216N     P=0.226N     P=0.223N   |
|INCIDENTAL TUMOR       |                                                    |  P=0.242N     P=0.316N     P=0.295N     P=0.500N   |
|LOGISTIC REGRESSION    |                                                    |  P=0.149N     P=0.269N     P=0.226N     P=0.254N   |
|COCHRAN-ARMITAGE       |                                                    |  P=0.154N                                          |
|FISHER EXACT           |                                                    |               P=0.247N     P=0.247N     P=0.247N   |
|=================================================================================================================================|
|                                                                                                                                 |
|Uterus                                                                                                                           |
|     Sarcoma Stromal or Polyp Stromal                                                                                            |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |                                                    |  3/50 (6%)    0/50 (0%)    0/50 (0%)    5/50 (10%) |
|ADJUSTED (b)           |                                                    |   8.3%         0.0%         0.0%        11.4%      |
|TERMINAL (d)           |                                                    |  1/29 (3%)    0/37 (0%)    0/33 (0%)    3/40 (8%)  |
|FIRST INCIDENCE (DAYS) |                                                    |   601          ---          ---          482       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |                                                    |  P=0.110      P=0.098N     P=0.109N     P=0.462    |
|INCIDENTAL TUMOR       |                                                    |  P=0.056      P=0.148N     P=0.145N     P=0.245    |
|LOGISTIC REGRESSION    |                                                    |  P=0.078      P=0.133N     P=0.120N     P=0.324    |
|COCHRAN-ARMITAGE       |                                                    |  P=0.081                                           |
|FISHER EXACT           |                                                    |               P=0.121N     P=0.121N     P=0.357    |
|=================================================================================================================================|
         DATE: 05/08/95                     EXPERIMENT: 88034 TEST: 04                                                 PAGE  17
                                  STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- 6  OZONE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      0.12 PPM     0.5 PPM      1.0 PPM   |   CONTROL      0.12 PPM     0.5 PPM      1.0 PPM   |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|All Organs                                                                                                                       |
|     Hemangiosarcoma                                                                                                             |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  0/50 (0%)    5/50 (10%)   1/50 (2%)    0/50 (0%)  |  2/50 (4%)    1/50 (2%)    6/50 (12%)   3/50 (6%)  |
|ADJUSTED (b)           |   0.0%        12.6%         3.3%         0.0%      |   6.7%         2.7%        17.2%         7.5%      |
|TERMINAL (d)           |  0/30 (0%)    2/34 (6%)    0/25 (0%)    0/27 (0%)  |  1/29 (3%)    1/37 (3%)    5/33 (15%)   3/40 (8%)  |
|FIRST INCIDENCE (DAYS) |   ---          540          659          ---       |   728          735 (T)      677          735 (T)   |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.168N     P=0.044 *    P=0.469        (e)      |  P=0.318      P=0.420N     P=0.182      P=0.641    |
|INCIDENTAL TUMOR       |  P=0.123N     P=0.036 *    P=0.500        (e)      |  P=0.243      P=0.495N     P=0.168      P=0.513    |
|LOGISTIC REGRESSION    |  P=0.122N     P=0.029 *    P=0.500        (e)      |  P=0.264      P=0.438N     P=0.165      P=0.605    |
|COCHRAN-ARMITAGE       |  P=0.125N                                          |  P=0.220                                           |
|FISHER EXACT           |               P=0.028 *    P=0.500        (e)      |               P=0.500N     P=0.134      P=0.500    |
|=================================================================================================================================|
|                                                                                                                                 |
|All Organs                                                                                                                       |
|     Hemangiosarcoma or Hemangioma                                                                                               |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  0/50 (0%)    5/50 (10%)   2/50 (4%)    1/50 (2%)  |  2/50 (4%)    1/50 (2%)    6/50 (12%)   3/50 (6%)  |
|ADJUSTED (b)           |   0.0%        12.6%         7.2%         3.7%      |   6.7%         2.7%        17.2%         7.5%      |
|TERMINAL (d)           |  0/30 (0%)    2/34 (6%)    1/25 (4%)    1/27 (4%)  |  1/29 (3%)    1/37 (3%)    5/33 (15%)   3/40 (8%)  |
|FIRST INCIDENCE (DAYS) |   ---          540          659          733 (T)   |   728          735 (T)      677          735 (T)   |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.442N     P=0.044 *    P=0.204      P=0.479    |  P=0.318      P=0.420N     P=0.182      P=0.641    |
|INCIDENTAL TUMOR       |  P=0.381N     P=0.036 *    P=0.220      P=0.479    |  P=0.243      P=0.495N     P=0.168      P=0.513    |
|LOGISTIC REGRESSION    |  P=0.378N     P=0.029 *    P=0.218      P=0.479    |  P=0.264      P=0.438N     P=0.165      P=0.605    |
|COCHRAN-ARMITAGE       |  P=0.359N                                          |  P=0.220                                           |
|FISHER EXACT           |               P=0.028 *    P=0.247      P=0.500    |               P=0.500N     P=0.134      P=0.500    |
|=================================================================================================================================|
         DATE: 05/08/95                     EXPERIMENT: 88034 TEST: 04                                                 PAGE  18
                                  STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- 6  OZONE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      0.12 PPM     0.5 PPM      1.0 PPM   |   CONTROL      0.12 PPM     0.5 PPM      1.0 PPM   |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|All Organs                                                                                                                       |
|     Malignant Lymphoma And Histiocytic Sarcoma                                                                                  |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  4/50 (8%)    8/50 (16%)   4/50 (8%)    7/50 (14%) |  7/50 (14%)  18/50 (36%)  14/50 (28%)  12/50 (24%) |
|ADJUSTED (b)           |  10.8%        21.0%        12.5%        19.8%      |  20.3%        40.2%        38.6%        27.3%      |
|TERMINAL (d)           |  1/30 (3%)    5/34 (15%)   2/25 (8%)    3/27 (11%) |  4/29 (14%)  11/37 (30%)  11/33 (33%)   9/40 (23%) |
|FIRST INCIDENCE (DAYS) |   596          600          544          484       |   636          471          704          482       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.289      P=0.229      P=0.554      P=0.213    |  P=0.415N     P=0.049 *    P=0.130      P=0.330    |
|INCIDENTAL TUMOR       |  P=0.455      P=0.146      P=0.604N     P=0.303    |  P=0.449      P=0.009 **   P=0.097      P=0.182    |
|LOGISTIC REGRESSION    |  P=0.411      P=0.183      P=0.640N     P=0.275    |  P=0.460      P=0.009 **   P=0.095      P=0.142    |
|COCHRAN-ARMITAGE       |  P=0.411                                           |  P=0.458                                           |
|FISHER EXACT           |               P=0.178      P=0.643N     P=0.262    |               P=0.010 **   P=0.070      P=0.154    |
|=================================================================================================================================|
|                                                                                                                                 |
|All Organs                                                                                                                       |
|     Malignant Lymphoma: Histiocytic, Lymphocytic, Mixed, NOS, or Undifferentiated                                               |
|     Cell Type                                                                                                                   |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |  4/50 (8%)    7/50 (14%)   4/50 (8%)    7/50 (14%) |  7/50 (14%)  17/50 (34%)  14/50 (28%)  11/50 (22%) |
|ADJUSTED (b)           |  10.8%        18.2%        12.5%        19.8%      |  20.3%        38.9%        38.6%        24.9%      |
|TERMINAL (d)           |  1/30 (3%)    4/34 (12%)   2/25 (8%)    3/27 (11%) |  4/29 (14%)  11/37 (30%)  11/33 (33%)   8/40 (20%) |
|FIRST INCIDENCE (DAYS) |   596          600          544          484       |   636          471          704          482       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.238      P=0.315      P=0.554      P=0.213    |  P=0.371N     P=0.070      P=0.130      P=0.407    |
|INCIDENTAL TUMOR       |  P=0.396      P=0.214      P=0.604N     P=0.303    |  P=0.515      P=0.017 *    P=0.097      P=0.240    |
|LOGISTIC REGRESSION    |  P=0.372      P=0.262      P=0.640N     P=0.275    |  P=0.513      P=0.017 *    P=0.095      P=0.200    |
|COCHRAN-ARMITAGE       |  P=0.347                                           |  P=0.509                                           |
|FISHER EXACT           |               P=0.262      P=0.643N     P=0.262    |               P=0.017 *    P=0.070      P=0.218    |
|=================================================================================================================================|
         DATE: 05/08/95                     EXPERIMENT: 88034 TEST: 04                                                 PAGE  19
                                  STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- 6  OZONE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      0.12 PPM     0.5 PPM      1.0 PPM   |   CONTROL      0.12 PPM     0.5 PPM      1.0 PPM   |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|All Organs                                                                                                                       |
|     Benign Tumors                                                                                                               |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            | 27/50 (54%)  33/50 (66%)  30/50 (60%)  29/50 (58%) | 33/50 (66%)  33/50 (66%)  32/50 (64%)  29/50 (58%) |
|ADJUSTED (b)           |  72.1%        80.3%        84.9%        75.2%      |  86.4%        78.5%        72.2%        62.7%      |
|TERMINAL (d)           | 20/30 (67%)  26/34 (76%)  20/25 (80%)  18/27 (67%) | 24/29 (83%)  28/37 (76%)  21/33 (64%)  23/40 (58%) |
|FIRST INCIDENCE (DAYS) |   362          440          464          462       |   511          653          488          482       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.174      P=0.369      P=0.105      P=0.239    |  P=0.031N*    P=0.109N     P=0.255N     P=0.021N*  |
|INCIDENTAL TUMOR       |  P=0.388      P=0.199      P=0.198      P=0.376    |  P=0.115N     P=0.321N     P=0.505N     P=0.107N   |
|LOGISTIC REGRESSION    |  P=0.347      P=0.206      P=0.224      P=0.321    |  P=0.176N     P=0.372N     P=0.453N     P=0.230N   |
|COCHRAN-ARMITAGE       |  P=0.502N                                          |  P=0.201N                                          |
|FISHER EXACT           |               P=0.154      P=0.343      P=0.420    |               P=0.583N     P=0.500N     P=0.268N   |
|=================================================================================================================================|
|                                                                                                                                 |
|All Organs                                                                                                                       |
|     Malignant Tumors                                                                                                            |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            | 25/50 (50%)  25/50 (50%)  25/50 (50%)  27/50 (54%) | 31/50 (62%)  28/50 (56%)  28/50 (56%)  26/50 (52%) |
|ADJUSTED (b)           |  58.5%        53.7%        60.3%        66.4%      |  65.5%        59.3%        63.5%        57.4%      |
|TERMINAL (d)           | 13/30 (43%)  13/34 (38%)  10/25 (40%)  14/27 (52%) | 13/29 (45%)  18/37 (49%)  17/33 (52%)  21/40 (53%) |
|FIRST INCIDENCE (DAYS) |   362          440          145          350       |   439          471          644          482       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.155      P=0.422N     P=0.350      P=0.280    |  P=0.081N     P=0.140N     P=0.216N     P=0.052N   |
|INCIDENTAL TUMOR       |  P=0.417      P=0.523      P=0.468N     P=0.403    |  P=0.382N     P=0.552N     P=0.417N     P=0.381N   |
|LOGISTIC REGRESSION    |  P=0.439      P=0.528      P=0.523N     P=0.417    |  P=0.221N     P=0.513N     P=0.341N     P=0.259N   |
|COCHRAN-ARMITAGE       |  P=0.367                                           |  P=0.215N                                          |
|FISHER EXACT           |               P=0.579N     P=0.579N     P=0.421    |               P=0.342N     P=0.342N     P=0.210N   |
|=================================================================================================================================|
         DATE: 05/08/95                     EXPERIMENT: 88034 TEST: 04                                                 PAGE  20
                                  STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- 6  OZONE
                                                 TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |   CONTROL      0.12 PPM     0.5 PPM      1.0 PPM   |   CONTROL      0.12 PPM     0.5 PPM      1.0 PPM   |
|                       |                                                    |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|All Organs                                                                                                                       |
|     Malignant and Benign Tumors                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |    #            #            #            #        |    #            #            #            #        |
|-----------            |                                                    |                                                    |
|OVERALL (a)            | 40/50 (80%)  43/50 (86%)  43/50 (86%)  40/50 (80%) | 47/50 (94%)  44/50 (88%)  42/50 (84%)  40/50 (80%) |
|ADJUSTED (b)           |  88.7%        87.8%        93.3%        90.8%      |  94.0%        89.8%        87.4%        86.8%      |
|TERMINAL (d)           | 25/30 (83%)  28/34 (82%)  22/25 (88%)  23/27 (85%) | 26/29 (90%)  32/37 (86%)  27/33 (82%)  34/40 (85%) |
|FIRST INCIDENCE (DAYS) |   362          440          145          350       |   439          471          488          482       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |  P=0.154      P=0.491N     P=0.106      P=0.305    |  P=0.008N**   P=0.045N*    P=0.089N     P=0.002N** |
|INCIDENTAL TUMOR       |  P=0.543N     P=0.368      P=0.315      P=0.515    |  P=0.046N*    P=0.301N     P=0.207N     P=0.031N*  |
|LOGISTIC REGRESSION    |  P=0.543N     P=0.328      P=0.271      P=0.503    |  P=0.028N*    P=0.254N     P=0.098N     P=0.036N*  |
|COCHRAN-ARMITAGE       |  P=0.439N                                          |  P=0.030N*                                         |
|FISHER EXACT           |               P=0.298      P=0.298      P=0.598N   |               P=0.243N     P=0.100N     P=0.036N*  |
|=================================================================================================================================|
 (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).