https://ntp.niehs.nih.gov/go/1865

TDMS Study 05107-06 Pathology Tables

NTP                                        STATISTICAL ANALYSIS OF PRIMARY TUMORS                              REPORT: PEIRPT08     
LAB: LITRI                                                  NICKEL SUBSULFIDE                                  DATE: 05/19/95       
EXPERIMENT: 05107 TEST: 06                                                                                     TIME: 23:03:08       
TEST TYPE:  CHRONIC                             CAGES FROM 0000 TO LAST CAGE                                   PAGE:       1        
CONT: Y01ES30108                                ROUTE: RESPIRATORY EXPOSURE WHOLE BODY                         NTP C#: C61654       
PATHOLOGIST: F. HAHN                                                                                           CAS: 12035722        
------------------------------------------------------------------------------------------------------------------------------------
               REASONS FOR REMOVAL:    ALL                                                                                          
               REMOVAL DATE RANGE:     ALL                                                                                          
               TREATMENT GROUPS:       INCLUDE ALL                                                                                  
NTP                                        STATISTICAL ANALYSIS OF PRIMARY TUMORS                              REPORT: PEIRPT08     
LAB: LITRI                                                  NICKEL SUBSULFIDE                                  DATE: 05/19/95       
EXPERIMENT: 05107 TEST: 06                                                                                     TIME: 23:03:08       
TEST TYPE:  CHRONIC                             CAGES FROM 0000 TO LAST CAGE                                                        
CONT: Y01ES30108                                ROUTE: RESPIRATORY EXPOSURE WHOLE BODY                         NTP C#: C61654       
PATHOLOGIST: F. HAHN                                                                                           CAS: 12035722        
                                                    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: LITRI                                                  NICKEL SUBSULFIDE                                  DATE: 05/19/95       
EXPERIMENT: 05107 TEST: 06                                                                                     TIME: 23:03:08       
TEST TYPE:  CHRONIC                             CAGES FROM 0000 TO LAST CAGE                                                        
CONT: Y01ES30108                                ROUTE: RESPIRATORY EXPOSURE WHOLE BODY                         NTP C#: C61654       
PATHOLOGIST: F. HAHN                                                                                           CAS: 12035722        
                                     SUMMARY OF STATISTICALLY SIGNIFICANT (P<=.05) RESULTS
                                       IN THE ANALYSIS OF THE STUDY OF NICKEL SUBSULFIDE
              ====================================================================================================
                                                           MALE MICE
                                                          -------------
                  ORGAN                               MORPHOLOGY
                 -------                             ------------
              Lung                          Alveolar/Bronchiolar Carcinoma or Alveolar/Bronchiolar Adenoma
              All Organs                    Benign Tumors
              ====================================================================================================
                                                           FEMALE MICE
                                                          -------------
                  ORGAN                               MORPHOLOGY
                 -------                             ------------
              Liver                         Hepatocellular Carcinoma
                                            Hepatocellular Carcinoma or Hepatoblastoma
              Lung                          Alveolar/Bronchiolar Carcinoma
                                            Alveolar/Bronchiolar Carcinoma or Alveolar/Bronchiolar Adenoma
              ====================================================================================================
         DATE: 05/19/95                     EXPERIMENT: 05107 TEST: 06                                                 PAGE   1
                              STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- NICKEL SUBSULFIDE
                                                 MALE TERMINAL SACRIFICE AT 106 WEEKS
                                                 FEMALE TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |      0.0MG/M3        0.6MG/M3        1.2MG/M3      |      0.0MG/M3        0.6MG/M3        1.2MG/M3      |
|                       |      LUNG TOX        LUNG TOX        LUNG TOX      |      LUNG TOX        LUNG TOX        LUNG TOX      |
|=================================================================================================================================|
|                                                                                                                                 |
|Adrenal Cortex                                                                                                                   |
|     Adenoma                                                                                                                     |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |     2/66 (3%)       0/64 (0%)       1/63 (2%)      |     1/63 (2%)       0/63 (0%)       0/65 (0%)      |
|ADJUSTED (b)           |      6.8%            0.0%            2.1%          |      2.8%            0.0%            0.0%          |
|INTERIM SACRIFICE 1 (c)|     0/0             0/0             0/0            |     0/0             0/0             0/0            |
|INTERIM SACRIFICE 2 (c)|     0/5 (0%)        0/5 (0%)        0/5 (0%)       |     0/5 (0%)        0/5 (0%)        0/5 (0%)       |
|TERMINAL (d)           |     1/26 (4%)       0/25 (0%)       0/25 (0%)      |     1/36 (3%)       0/34 (0%)       0/38 (0%)      |
|FIRST INCIDENCE (DAYS) |      679             ---             485           |      733 (T)         ---             ---           |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |     P=0.382N        P=0.255N        P=0.525N       |     P=0.265N        P=0.511N        P=0.489N       |
|INCIDENTAL TUMOR       |     P=0.313N        P=0.244N        P=0.435N       |     P=0.265N        P=0.511N        P=0.489N       |
|LOGISTIC REGRESSION    |     P=0.374N        P=0.246N        P=0.517N       |     P=0.265N        P=0.511N        P=0.489N       |
|COCHRAN-ARMITAGE       |     P=0.373N                                       |     P=0.266N                                       |
|FISHER EXACT           |                     P=0.256N        P=0.518N       |                     P=0.500N        P=0.492N       |
|=================================================================================================================================|
|                                                                                                                                 |
|Liver                                                                                                                            |
|     Hemangiosarcoma                                                                                                             |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |     0/66 (0%)       0/64 (0%)       1/64 (2%)      |     2/63 (3%)       1/65 (2%)       2/65 (3%)      |
|ADJUSTED (b)           |      0.0%            0.0%            2.6%          |      5.0%            2.9%            4.2%          |
|INTERIM SACRIFICE 1 (c)|     0/0             0/0             0/0            |     0/0             0/0             0/0            |
|INTERIM SACRIFICE 2 (c)|     0/5 (0%)        0/5 (0%)        0/5 (0%)       |     0/5 (0%)        0/5 (0%)        1/5 (20%)      |
|TERMINAL (d)           |     0/26 (0%)       0/25 (0%)       0/25 (0%)      |     1/36 (3%)       1/34 (3%)       1/38 (3%)      |
|FIRST INCIDENCE (DAYS) |      ---             ---             661           |      680             733 (T)         477 (I)       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |     P=0.288           (e)           P=0.522        |     P=0.596N        P=0.519N        P=0.682N       |
|INCIDENTAL TUMOR       |     P=0.334           (e)           P=0.581        |     P=0.592         P=0.503N        P=0.663        |
|LOGISTIC REGRESSION    |     P=0.265           (e)           P=0.493        |     P=0.600N        P=0.502N        P=0.683N       |
|COCHRAN-ARMITAGE       |     P=0.266                                        |     P=0.598N                                       |
|FISHER EXACT           |                       (e)           P=0.492        |                     P=0.488N        P=0.679N       |
|=================================================================================================================================|
         DATE: 05/19/95                     EXPERIMENT: 05107 TEST: 06                                                 PAGE   2
                              STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- NICKEL SUBSULFIDE
                                                 MALE TERMINAL SACRIFICE AT 106 WEEKS
                                                 FEMALE TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |      0.0MG/M3        0.6MG/M3        1.2MG/M3      |      0.0MG/M3        0.6MG/M3        1.2MG/M3      |
|                       |      LUNG TOX        LUNG TOX        LUNG TOX      |      LUNG TOX        LUNG TOX        LUNG TOX      |
|=================================================================================================================================|
|                                                                                                                                 |
|Liver                                                                                                                            |
|     Hepatocellular Adenoma                                                                                                      |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |    14/66 (21%)     11/64 (17%)     15/64 (23%)     |    14/63 (22%)     10/65 (15%)     10/65 (15%)     |
|ADJUSTED (b)           |     38.5%           28.3%           42.8%          |     32.9%           25.7%           23.8%          |
|INTERIM SACRIFICE 1 (c)|     0/0             0/0             0/0            |     0/0             0/0             0/0            |
|INTERIM SACRIFICE 2 (c)|     1/5 (20%)       2/5 (40%)       1/5 (20%)      |     1/5 (20%)       0/5 (0%)        0/5 (0%)       |
|TERMINAL (d)           |     7/26 (27%)      3/25 (12%)      8/25 (32%)     |     9/36 (25%)      7/34 (21%)      7/38 (18%)     |
|FIRST INCIDENCE (DAYS) |      476 (I)         476 (I)         476 (I)       |      477 (I)         520             563           |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |     P=0.453         P=0.380N        P=0.492        |     P=0.181N        P=0.288N        P=0.213N       |
|INCIDENTAL TUMOR       |     P=0.332         P=0.386N        P=0.350        |     P=0.217N        P=0.247N        P=0.287N       |
|LOGISTIC REGRESSION    |     P=0.411         P=0.371N        P=0.452        |     P=0.187N        P=0.242N        P=0.223N       |
|COCHRAN-ARMITAGE       |     P=0.422                                        |     P=0.186N                                       |
|FISHER EXACT           |                     P=0.360N        P=0.462        |                     P=0.222N        P=0.222N       |
|=================================================================================================================================|
|                                                                                                                                 |
|Liver                                                                                                                            |
|     Hepatocellular Carcinoma                                                                                                    |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |    11/66 (17%)     17/64 (27%)     13/64 (20%)     |    11/63 (17%)      9/65 (14%)      4/65 (6%)      |
|ADJUSTED (b)           |     26.8%           40.2%           29.4%          |     25.0%           21.2%            8.4%          |
|INTERIM SACRIFICE 1 (c)|     0/0             0/0             0/0            |     0/0             0/0             0/0            |
|INTERIM SACRIFICE 2 (c)|     0/5 (0%)        0/5 (0%)        1/5 (20%)      |     0/5 (0%)        0/5 (0%)        0/5 (0%)       |
|TERMINAL (d)           |     3/26 (12%)      5/25 (20%)      1/25 (4%)      |     4/36 (11%)      3/34 (9%)       1/38 (3%)      |
|FIRST INCIDENCE (DAYS) |      434             415             450           |      603             552             563           |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |     P=0.370         P=0.137         P=0.412        |     P=0.043N*       P=0.434N        P=0.051N       |
|INCIDENTAL TUMOR       |     P=0.282         P=0.104         P=0.364        |     P=0.030N*       P=0.347N        P=0.040N*      |
|LOGISTIC REGRESSION    |     P=0.187         P=0.124         P=0.212        |     P=0.033N*       P=0.344N        P=0.042N*      |
|COCHRAN-ARMITAGE       |     P=0.340                                        |     P=0.035N*                                      |
|FISHER EXACT           |                     P=0.123         P=0.378        |                     P=0.375N        P=0.042N*      |
|=================================================================================================================================|
         DATE: 05/19/95                     EXPERIMENT: 05107 TEST: 06                                                 PAGE   3
                              STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- NICKEL SUBSULFIDE
                                                 MALE TERMINAL SACRIFICE AT 106 WEEKS
                                                 FEMALE TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |      0.0MG/M3        0.6MG/M3        1.2MG/M3      |      0.0MG/M3        0.6MG/M3        1.2MG/M3      |
|                       |      LUNG TOX        LUNG TOX        LUNG TOX      |      LUNG TOX        LUNG TOX        LUNG TOX      |
|=================================================================================================================================|
|                                                                                                                                 |
|Liver                                                                                                                            |
|     Hepatocellular Carcinoma or Hepatoblastoma                                                                                  |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |    11/66 (17%)     17/64 (27%)     13/64 (20%)     |    11/63 (17%)      9/65 (14%)      4/65 (6%)      |
|ADJUSTED (b)           |     26.8%           40.2%           29.4%          |     25.0%           21.2%            8.4%          |
|INTERIM SACRIFICE 1 (c)|     0/0             0/0             0/0            |     0/0             0/0             0/0            |
|INTERIM SACRIFICE 2 (c)|     0/5 (0%)        0/5 (0%)        1/5 (20%)      |     0/5 (0%)        0/5 (0%)        0/5 (0%)       |
|TERMINAL (d)           |     3/26 (12%)      5/25 (20%)      1/25 (4%)      |     4/36 (11%)      3/34 (9%)       1/38 (3%)      |
|FIRST INCIDENCE (DAYS) |      434             415             450           |      603             552             563           |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |     P=0.370         P=0.137         P=0.412        |     P=0.043N*       P=0.434N        P=0.051N       |
|INCIDENTAL TUMOR       |     P=0.282         P=0.104         P=0.364        |     P=0.030N*       P=0.347N        P=0.040N*      |
|LOGISTIC REGRESSION    |     P=0.187         P=0.124         P=0.212        |     P=0.033N*       P=0.344N        P=0.042N*      |
|COCHRAN-ARMITAGE       |     P=0.340                                        |     P=0.035N*                                      |
|FISHER EXACT           |                     P=0.123         P=0.378        |                     P=0.375N        P=0.042N*      |
|=================================================================================================================================|
|                                                                                                                                 |
|Liver                                                                                                                            |
|     Hepatocellular Carcinoma or Hepatocellular Adenoma                                                                          |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |    25/66 (38%)     24/64 (38%)     26/64 (41%)     |    21/63 (33%)     18/65 (28%)     13/65 (20%)     |
|ADJUSTED (b)           |     57.1%           51.2%           58.7%          |     45.7%           41.6%           29.3%          |
|INTERIM SACRIFICE 1 (c)|     0/0             0/0             0/0            |     0/0             0/0             0/0            |
|INTERIM SACRIFICE 2 (c)|     1/5 (20%)       2/5 (40%)       1/5 (20%)      |     1/5 (20%)       0/5 (0%)        0/5 (0%)       |
|TERMINAL (d)           |    10/26 (38%)      6/25 (24%)      9/25 (36%)     |    12/36 (33%)     10/34 (29%)      8/38 (21%)     |
|FIRST INCIDENCE (DAYS) |      434             415             450           |      477 (I)         520             563           |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |     P=0.451         P=0.554         P=0.488        |     P=0.063N        P=0.408N        P=0.073N       |
|INCIDENTAL TUMOR       |     P=0.341         P=0.555         P=0.369        |     P=0.067N        P=0.324N        P=0.084N       |
|LOGISTIC REGRESSION    |     P=0.232         P=0.562N        P=0.269        |     P=0.054N        P=0.340N        P=0.065N       |
|COCHRAN-ARMITAGE       |     P=0.409                                        |     P=0.055N                                       |
|FISHER EXACT           |                     P=0.554N        P=0.444        |                     P=0.308N        P=0.066N       |
|=================================================================================================================================|
         DATE: 05/19/95                     EXPERIMENT: 05107 TEST: 06                                                 PAGE   4
                              STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- NICKEL SUBSULFIDE
                                                 MALE TERMINAL SACRIFICE AT 106 WEEKS
                                                 FEMALE TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |      0.0MG/M3        0.6MG/M3        1.2MG/M3      |      0.0MG/M3        0.6MG/M3        1.2MG/M3      |
|                       |      LUNG TOX        LUNG TOX        LUNG TOX      |      LUNG TOX        LUNG TOX        LUNG TOX      |
|=================================================================================================================================|
|                                                                                                                                 |
|Liver                                                                                                                            |
|     Hepatocellular Carcinoma, Hepatocellular Adenoma, or Hepatoblastoma                                                         |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |    25/66 (38%)     24/64 (38%)     26/64 (41%)     |    21/63 (33%)     18/65 (28%)     13/65 (20%)     |
|ADJUSTED (b)           |     57.1%           51.2%           58.7%          |     45.7%           41.6%           29.3%          |
|INTERIM SACRIFICE 1 (c)|     0/0             0/0             0/0            |     0/0             0/0             0/0            |
|INTERIM SACRIFICE 2 (c)|     1/5 (20%)       2/5 (40%)       1/5 (20%)      |     1/5 (20%)       0/5 (0%)        0/5 (0%)       |
|TERMINAL (d)           |    10/26 (38%)      6/25 (24%)      9/25 (36%)     |    12/36 (33%)     10/34 (29%)      8/38 (21%)     |
|FIRST INCIDENCE (DAYS) |      434             415             450           |      477 (I)         520             563           |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |     P=0.451         P=0.554         P=0.488        |     P=0.063N        P=0.408N        P=0.073N       |
|INCIDENTAL TUMOR       |     P=0.341         P=0.555         P=0.369        |     P=0.067N        P=0.324N        P=0.084N       |
|LOGISTIC REGRESSION    |     P=0.232         P=0.562N        P=0.269        |     P=0.054N        P=0.340N        P=0.065N       |
|COCHRAN-ARMITAGE       |     P=0.409                                        |     P=0.055N                                       |
|FISHER EXACT           |                     P=0.554N        P=0.444        |                     P=0.308N        P=0.066N       |
|=================================================================================================================================|
|                                                                                                                                 |
|Lung                                                                                                                             |
|     Alveolar/Bronchiolar Adenoma                                                                                                |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |     6/71 (8%)       3/69 (4%)       2/68 (3%)      |     3/68 (4%)       1/69 (1%)       1/70 (1%)      |
|ADJUSTED (b)           |     19.8%           10.8%            7.7%          |      7.8%            2.9%            2.6%          |
|INTERIM SACRIFICE 1 (c)|     0/5 (0%)        0/5 (0%)        0/5 (0%)       |     0/5 (0%)        0/5 (0%)        0/5 (0%)       |
|INTERIM SACRIFICE 2 (c)|     0/5 (0%)        0/5 (0%)        0/5 (0%)       |     0/5 (0%)        0/5 (0%)        0/5 (0%)       |
|TERMINAL (d)           |     3/26 (12%)      2/25 (8%)       1/25 (4%)      |     2/36 (6%)       1/34 (3%)       1/38 (3%)      |
|FIRST INCIDENCE (DAYS) |      641             661             734           |      683             733 (T)         733 (T)       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |     P=0.097N        P=0.269N        P=0.144N       |     P=0.193N        P=0.324N        P=0.290N       |
|INCIDENTAL TUMOR       |     P=0.076N        P=0.261N        P=0.124N       |     P=0.212N        P=0.314N        P=0.331N       |
|LOGISTIC REGRESSION    |     P=0.088N        P=0.260N        P=0.130N       |     P=0.193N        P=0.309N        P=0.293N       |
|COCHRAN-ARMITAGE       |     P=0.103N                                       |     P=0.195N                                       |
|FISHER EXACT           |                     P=0.261N        P=0.152N       |                     P=0.304N        P=0.299N       |
|=================================================================================================================================|
         DATE: 05/19/95                     EXPERIMENT: 05107 TEST: 06                                                 PAGE   5
                              STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- NICKEL SUBSULFIDE
                                                 MALE TERMINAL SACRIFICE AT 106 WEEKS
                                                 FEMALE TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |      0.0MG/M3        0.6MG/M3        1.2MG/M3      |      0.0MG/M3        0.6MG/M3        1.2MG/M3      |
|                       |      LUNG TOX        LUNG TOX        LUNG TOX      |      LUNG TOX        LUNG TOX        LUNG TOX      |
|=================================================================================================================================|
|                                                                                                                                 |
|Lung                                                                                                                             |
|     Alveolar/Bronchiolar Carcinoma                                                                                              |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |     7/71 (10%)      2/69 (3%)       4/68 (6%)      |     7/68 (10%)      1/69 (1%)       2/70 (3%)      |
|ADJUSTED (b)           |     23.7%            8.0%           14.3%          |     18.7%            1.9%            5.3%          |
|INTERIM SACRIFICE 1 (c)|     0/5 (0%)        0/5 (0%)        0/5 (0%)       |     0/5 (0%)        0/5 (0%)        0/5 (0%)       |
|INTERIM SACRIFICE 2 (c)|     0/5 (0%)        0/5 (0%)        0/5 (0%)       |     0/5 (0%)        0/5 (0%)        0/5 (0%)       |
|TERMINAL (d)           |     5/26 (19%)      2/25 (8%)       3/25 (12%)     |     6/36 (17%)      0/34 (0%)       2/38 (5%)      |
|FIRST INCIDENCE (DAYS) |      552             737 (T)         661           |      683             552             733 (T)       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |     P=0.200N        P=0.092N        P=0.279N       |     P=0.033N*       P=0.040N*       P=0.070N       |
|INCIDENTAL TUMOR       |     P=0.196N        P=0.092N        P=0.278N       |     P=0.031N*       P=0.035N*       P=0.081N       |
|LOGISTIC REGRESSION    |     P=0.183N        P=0.088N        P=0.259N       |     P=0.033N*       P=0.033N*       P=0.070N       |
|COCHRAN-ARMITAGE       |     P=0.209N                                       |     P=0.034N*                                      |
|FISHER EXACT           |                     P=0.090N        P=0.291N       |                     P=0.030N*       P=0.076N       |
|=================================================================================================================================|
|                                                                                                                                 |
|Lung                                                                                                                             |
|     Alveolar/Bronchiolar Carcinoma or Alveolar/Bronchiolar Adenoma                                                              |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |    13/71 (18%)      5/69 (7%)       6/68 (9%)      |     9/68 (13%)      2/69 (3%)       3/70 (4%)      |
|ADJUSTED (b)           |     40.7%           18.5%           21.4%          |     24.1%            4.8%            7.9%          |
|INTERIM SACRIFICE 1 (c)|     0/5 (0%)        0/5 (0%)        0/5 (0%)       |     0/5 (0%)        0/5 (0%)        0/5 (0%)       |
|INTERIM SACRIFICE 2 (c)|     0/5 (0%)        0/5 (0%)        0/5 (0%)       |     0/5 (0%)        0/5 (0%)        0/5 (0%)       |
|TERMINAL (d)           |     8/26 (31%)      4/25 (16%)      4/25 (16%)     |     8/36 (22%)      1/34 (3%)       3/38 (8%)      |
|FIRST INCIDENCE (DAYS) |      552             661             661           |      683             552             733 (T)       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |     P=0.045N*       P=0.046N*       P=0.076N       |     P=0.026N*       P=0.035N*       P=0.051N       |
|INCIDENTAL TUMOR       |     P=0.033N*       P=0.041N*       P=0.062N       |     P=0.024N*       P=0.031N*       P=0.058N       |
|LOGISTIC REGRESSION    |     P=0.034N*       P=0.038N*       P=0.057N       |     P=0.027N*       P=0.028N*       P=0.050N       |
|COCHRAN-ARMITAGE       |     P=0.051N                                       |     P=0.028N*                                      |
|FISHER EXACT           |                     P=0.043N*       P=0.083N       |                     P=0.026N*       P=0.058N       |
|=================================================================================================================================|
         DATE: 05/19/95                     EXPERIMENT: 05107 TEST: 06                                                 PAGE   6
                              STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- NICKEL SUBSULFIDE
                                                 MALE TERMINAL SACRIFICE AT 106 WEEKS
                                                 FEMALE TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |      0.0MG/M3        0.6MG/M3        1.2MG/M3      |      0.0MG/M3        0.6MG/M3        1.2MG/M3      |
|                       |      LUNG TOX        LUNG TOX        LUNG TOX      |      LUNG TOX        LUNG TOX        LUNG TOX      |
|=================================================================================================================================|
|                                                                                                                                 |
|Mammary Gland                                                                                                                    |
|     Carcinoma                                                                                                                   |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |       #               #               #            |       #               #               #            |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |     0/71 (0%)       0/70 (0%)       0/70 (0%)      |     1/68 (1%)       3/70 (4%)       0/70 (0%)      |
|ADJUSTED (b)           |      0.0%            0.0%            0.0%          |      2.8%            8.3%            0.0%          |
|INTERIM SACRIFICE 1 (c)|     0/5 (0%)        0/5 (0%)        0/5 (0%)       |     0/5 (0%)        0/5 (0%)        0/5 (0%)       |
|INTERIM SACRIFICE 2 (c)|     0/5 (0%)        0/5 (0%)        0/5 (0%)       |     0/5 (0%)        0/5 (0%)        0/5 (0%)       |
|TERMINAL (d)           |     0/26 (0%)       0/25 (0%)       0/25 (0%)      |     1/36 (3%)       2/34 (6%)       0/38 (0%)      |
|FIRST INCIDENCE (DAYS) |      ---             ---             ---           |      733 (T)         711             ---           |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |       (e)             (e)             (e)          |     P=0.361N        P=0.294         P=0.489N       |
|INCIDENTAL TUMOR       |       (e)             (e)             (e)          |     P=0.397N        P=0.299         P=0.489N       |
|LOGISTIC REGRESSION    |       (e)             (e)             (e)          |     P=0.365N        P=0.297         P=0.489N       |
|COCHRAN-ARMITAGE       |       (e)                                          |     P=0.369N                                       |
|FISHER EXACT           |                       (e)             (e)          |                     P=0.321         P=0.493N       |
|=================================================================================================================================|
|                                                                                                                                 |
|Ovary                                                                                                                            |
|     Cystadenoma                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |                                                    |     2/62 (3%)       0/63 (0%)       1/65 (2%)      |
|ADJUSTED (b)           |                                                    |      5.3%            0.0%            1.9%          |
|INTERIM SACRIFICE 1 (c)|                                                    |     0/0             0/0             0/0            |
|INTERIM SACRIFICE 2 (c)|                                                    |     0/4 (0%)        0/5 (0%)        0/5 (0%)       |
|TERMINAL (d)           |                                                    |     1/36 (3%)       0/34 (0%)       0/38 (0%)      |
|FIRST INCIDENCE (DAYS) |                                                    |      723             ---             580           |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |                                                    |     P=0.347N        P=0.255N        P=0.478N       |
|INCIDENTAL TUMOR       |                                                    |     P=0.339N        P=0.246N        P=0.479N       |
|LOGISTIC REGRESSION    |                                                    |     P=0.351N        P=0.243N        P=0.486N       |
|COCHRAN-ARMITAGE       |                                                    |     P=0.348N                                       |
|FISHER EXACT           |                                                    |                     P=0.244N        P=0.482N       |
|=================================================================================================================================|
         DATE: 05/19/95                     EXPERIMENT: 05107 TEST: 06                                                 PAGE   7
                              STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- NICKEL SUBSULFIDE
                                                 MALE TERMINAL SACRIFICE AT 106 WEEKS
                                                 FEMALE TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |      0.0MG/M3        0.6MG/M3        1.2MG/M3      |      0.0MG/M3        0.6MG/M3        1.2MG/M3      |
|                       |      LUNG TOX        LUNG TOX        LUNG TOX      |      LUNG TOX        LUNG TOX        LUNG TOX      |
|=================================================================================================================================|
|                                                                                                                                 |
|Pituitary Gland: Pars Distalis or Unspecified Site                                                                               |
|     Adenoma                                                                                                                     |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |     0/63 (0%)       0/63 (0%)       1/60 (2%)      |     8/62 (13%)      5/62 (8%)       3/65 (5%)      |
|ADJUSTED (b)           |      0.0%            0.0%            4.3%          |     21.0%           13.6%            7.0%          |
|INTERIM SACRIFICE 1 (c)|     0/0             0/0             0/0            |     0/0             0/0             0/0            |
|INTERIM SACRIFICE 2 (c)|     0/5 (0%)        0/5 (0%)        0/5 (0%)       |     0/4 (0%)        0/5 (0%)        0/5 (0%)       |
|TERMINAL (d)           |     0/24 (0%)       0/25 (0%)       1/23 (4%)      |     7/36 (19%)      3/34 (9%)       1/38 (3%)      |
|FIRST INCIDENCE (DAYS) |      ---             ---             737 (T)       |      536             712             607           |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |     P=0.262           (e)           P=0.492        |     P=0.066N        P=0.309N        P=0.089N       |
|INCIDENTAL TUMOR       |     P=0.262           (e)           P=0.492        |     P=0.079N        P=0.296N        P=0.096N       |
|LOGISTIC REGRESSION    |     P=0.262           (e)           P=0.492        |     P=0.067N        P=0.289N        P=0.092N       |
|COCHRAN-ARMITAGE       |     P=0.262                                        |     P=0.065N                                       |
|FISHER EXACT           |                       (e)           P=0.488        |                     P=0.280N        P=0.089N       |
|=================================================================================================================================|
|                                                                                                                                 |
|Skin                                                                                                                             |
|     Fibroma, Fibrosarcoma, Sarcoma, Myxoma, Myxosarcoma, or Fibrous Histiocytoma                                                |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |       #               #               #            |       #               #               #            |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |     1/71 (1%)       1/70 (1%)       1/70 (1%)      |     2/68 (3%)       0/70 (0%)       3/70 (4%)      |
|ADJUSTED (b)           |      1.9%            3.0%            4.0%          |      4.7%            0.0%            6.1%          |
|INTERIM SACRIFICE 1 (c)|     0/5 (0%)        0/5 (0%)        0/5 (0%)       |     0/5 (0%)        0/5 (0%)        0/5 (0%)       |
|INTERIM SACRIFICE 2 (c)|     0/5 (0%)        0/5 (0%)        0/5 (0%)       |     0/5 (0%)        0/5 (0%)        0/5 (0%)       |
|TERMINAL (d)           |     0/26 (0%)       0/25 (0%)       1/25 (4%)      |     1/36 (3%)       0/34 (0%)       0/38 (0%)      |
|FIRST INCIDENCE (DAYS) |      499             661             737 (T)       |      598             ---             507           |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |     P=0.632         P=0.748         P=0.741        |     P=0.408         P=0.246N        P=0.519        |
|INCIDENTAL TUMOR       |     P=0.567N        P=0.760         P=0.733N       |     P=0.433         P=0.226N        P=0.543        |
|LOGISTIC REGRESSION    |     P=0.633         P=0.759         P=0.758        |     P=0.401         P=0.235N        P=0.513        |
|COCHRAN-ARMITAGE       |     P=0.635                                        |     P=0.401                                        |
|FISHER EXACT           |                     P=0.748         P=0.748        |                     P=0.241N        P=0.514        |
|=================================================================================================================================|
         DATE: 05/19/95                     EXPERIMENT: 05107 TEST: 06                                                 PAGE   8
                              STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- NICKEL SUBSULFIDE
                                                 MALE TERMINAL SACRIFICE AT 106 WEEKS
                                                 FEMALE TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |      0.0MG/M3        0.6MG/M3        1.2MG/M3      |      0.0MG/M3        0.6MG/M3        1.2MG/M3      |
|                       |      LUNG TOX        LUNG TOX        LUNG TOX      |      LUNG TOX        LUNG TOX        LUNG TOX      |
|=================================================================================================================================|
|                                                                                                                                 |
|Skin                                                                                                                             |
|     Fibrosarcoma                                                                                                                |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |       #               #               #            |       #               #               #            |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |     1/71 (1%)       0/70 (0%)       0/70 (0%)      |     2/68 (3%)       0/70 (0%)       2/70 (3%)      |
|ADJUSTED (b)           |      1.9%            0.0%            0.0%          |      4.7%            0.0%            3.7%          |
|INTERIM SACRIFICE 1 (c)|     0/5 (0%)        0/5 (0%)        0/5 (0%)       |     0/5 (0%)        0/5 (0%)        0/5 (0%)       |
|INTERIM SACRIFICE 2 (c)|     0/5 (0%)        0/5 (0%)        0/5 (0%)       |     0/5 (0%)        0/5 (0%)        0/5 (0%)       |
|TERMINAL (d)           |     0/26 (0%)       0/25 (0%)       0/25 (0%)      |     1/36 (3%)       0/34 (0%)       0/38 (0%)      |
|FIRST INCIDENCE (DAYS) |      499             ---             ---           |      598             ---             507           |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |     P=0.289N        P=0.515N        P=0.528N       |     P=0.611N        P=0.246N        P=0.682N       |
|INCIDENTAL TUMOR       |     P=0.235N        P=0.500N        P=0.443N       |     P=0.541N        P=0.226N        P=0.612N       |
|LOGISTIC REGRESSION    |     P=0.267N        P=0.493N        P=0.498N       |     P=0.612N        P=0.235N        P=0.683N       |
|COCHRAN-ARMITAGE       |     P=0.272N                                       |     P=0.613N                                       |
|FISHER EXACT           |                     P=0.504N        P=0.504N       |                     P=0.241N        P=0.679N       |
|=================================================================================================================================|
|                                                                                                                                 |
|Skin                                                                                                                             |
|     Fibrosarcoma, Sarcoma, Myxosarcoma, or Fibrous Histiocytoma                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |       #               #               #            |       #               #               #            |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |     1/71 (1%)       1/70 (1%)       1/70 (1%)      |     2/68 (3%)       0/70 (0%)       2/70 (3%)      |
|ADJUSTED (b)           |      1.9%            3.0%            4.0%          |      4.7%            0.0%            3.7%          |
|INTERIM SACRIFICE 1 (c)|     0/5 (0%)        0/5 (0%)        0/5 (0%)       |     0/5 (0%)        0/5 (0%)        0/5 (0%)       |
|INTERIM SACRIFICE 2 (c)|     0/5 (0%)        0/5 (0%)        0/5 (0%)       |     0/5 (0%)        0/5 (0%)        0/5 (0%)       |
|TERMINAL (d)           |     0/26 (0%)       0/25 (0%)       1/25 (4%)      |     1/36 (3%)       0/34 (0%)       0/38 (0%)      |
|FIRST INCIDENCE (DAYS) |      499             661             737 (T)       |      598             ---             507           |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |     P=0.632         P=0.748         P=0.741        |     P=0.611N        P=0.246N        P=0.682N       |
|INCIDENTAL TUMOR       |     P=0.567N        P=0.760         P=0.733N       |     P=0.541N        P=0.226N        P=0.612N       |
|LOGISTIC REGRESSION    |     P=0.633         P=0.759         P=0.758        |     P=0.612N        P=0.235N        P=0.683N       |
|COCHRAN-ARMITAGE       |     P=0.635                                        |     P=0.613N                                       |
|FISHER EXACT           |                     P=0.748         P=0.748        |                     P=0.241N        P=0.679N       |
|=================================================================================================================================|
         DATE: 05/19/95                     EXPERIMENT: 05107 TEST: 06                                                 PAGE   9
                              STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- NICKEL SUBSULFIDE
                                                 MALE TERMINAL SACRIFICE AT 106 WEEKS
                                                 FEMALE TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |      0.0MG/M3        0.6MG/M3        1.2MG/M3      |      0.0MG/M3        0.6MG/M3        1.2MG/M3      |
|                       |      LUNG TOX        LUNG TOX        LUNG TOX      |      LUNG TOX        LUNG TOX        LUNG TOX      |
|=================================================================================================================================|
|                                                                                                                                 |
|Thyroid Gland: Follicular Cell                                                                                                   |
|     Adenoma                                                                                                                     |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |     4/66 (6%)       1/64 (2%)       1/64 (2%)      |     2/63 (3%)       4/65 (6%)       3/65 (5%)      |
|ADJUSTED (b)           |     12.3%            3.6%            4.0%          |      5.1%           11.2%            7.9%          |
|INTERIM SACRIFICE 1 (c)|     0/0             0/0             0/0            |     0/0             0/0             0/0            |
|INTERIM SACRIFICE 2 (c)|     0/5 (0%)        0/5 (0%)        0/5 (0%)       |     0/5 (0%)        0/5 (0%)        0/5 (0%)       |
|TERMINAL (d)           |     2/26 (8%)       0/25 (0%)       1/25 (4%)      |     1/36 (3%)       3/34 (9%)       3/38 (8%)      |
|FIRST INCIDENCE (DAYS) |      313             704             737 (T)       |      691             711             733 (T)       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |     P=0.106N        P=0.194N        P=0.188N       |     P=0.445         P=0.324         P=0.522        |
|INCIDENTAL TUMOR       |     P=0.076N        P=0.169N        P=0.149N       |     P=0.394         P=0.334         P=0.479        |
|LOGISTIC REGRESSION    |     P=0.110N        P=0.193N        P=0.192N       |     P=0.437         P=0.330         P=0.517        |
|COCHRAN-ARMITAGE       |     P=0.108N                                       |     P=0.432                                        |
|FISHER EXACT           |                     P=0.192N        P=0.192N       |                     P=0.355         P=0.515        |
|=================================================================================================================================|
|                                                                                                                                 |
|Thyroid Gland: Follicular Cell                                                                                                   |
|     Carcinoma or Adenoma                                                                                                        |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |                                                    |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |     4/66 (6%)       1/64 (2%)       1/64 (2%)      |     3/63 (5%)       4/65 (6%)       3/65 (5%)      |
|ADJUSTED (b)           |     12.3%            3.6%            4.0%          |      7.9%           11.2%            7.9%          |
|INTERIM SACRIFICE 1 (c)|     0/0             0/0             0/0            |     0/0             0/0             0/0            |
|INTERIM SACRIFICE 2 (c)|     0/5 (0%)        0/5 (0%)        0/5 (0%)       |     0/5 (0%)        0/5 (0%)        0/5 (0%)       |
|TERMINAL (d)           |     2/26 (8%)       0/25 (0%)       1/25 (4%)      |     2/36 (6%)       3/34 (9%)       3/38 (8%)      |
|FIRST INCIDENCE (DAYS) |      313             704             737 (T)       |      691             711             733 (T)       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |     P=0.106N        P=0.194N        P=0.188N       |     P=0.550N        P=0.480         P=0.639N       |
|INCIDENTAL TUMOR       |     P=0.076N        P=0.169N        P=0.149N       |     P=0.561         P=0.491         P=0.649        |
|LOGISTIC REGRESSION    |     P=0.110N        P=0.193N        P=0.192N       |     P=0.557N        P=0.491         P=0.646N       |
|COCHRAN-ARMITAGE       |     P=0.108N                                       |     P=0.563N                                       |
|FISHER EXACT           |                     P=0.192N        P=0.192N       |                     P=0.518         P=0.645N       |
|=================================================================================================================================|
         DATE: 05/19/95                     EXPERIMENT: 05107 TEST: 06                                                 PAGE  10
                              STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- NICKEL SUBSULFIDE
                                                 MALE TERMINAL SACRIFICE AT 106 WEEKS
                                                 FEMALE TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |      0.0MG/M3        0.6MG/M3        1.2MG/M3      |      0.0MG/M3        0.6MG/M3        1.2MG/M3      |
|                       |      LUNG TOX        LUNG TOX        LUNG TOX      |      LUNG TOX        LUNG TOX        LUNG TOX      |
|=================================================================================================================================|
|                                                                                                                                 |
|Tooth                                                                                                                            |
|     Odontoma                                                                                                                    |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |       #               #               #            |       #               #               #            |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |     0/71 (0%)       0/70 (0%)       2/70 (3%)      |     0/68 (0%)       0/70 (0%)       0/70 (0%)      |
|ADJUSTED (b)           |      0.0%            0.0%            5.4%          |      0.0%            0.0%            0.0%          |
|INTERIM SACRIFICE 1 (c)|     0/5 (0%)        0/5 (0%)        0/5 (0%)       |     0/5 (0%)        0/5 (0%)        0/5 (0%)       |
|INTERIM SACRIFICE 2 (c)|     0/5 (0%)        0/5 (0%)        0/5 (0%)       |     0/5 (0%)        0/5 (0%)        0/5 (0%)       |
|TERMINAL (d)           |     0/26 (0%)       0/25 (0%)       1/25 (4%)      |     0/36 (0%)       0/34 (0%)       0/38 (0%)      |
|FIRST INCIDENCE (DAYS) |      ---             ---             144           |      ---             ---             ---           |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |     P=0.095           (e)           P=0.234        |       (e)             (e)             (e)          |
|INCIDENTAL TUMOR       |     P=0.100           (e)           P=0.267        |       (e)             (e)             (e)          |
|LOGISTIC REGRESSION    |     P=0.095           (e)           P=0.244        |       (e)             (e)             (e)          |
|COCHRAN-ARMITAGE       |     P=0.095                                        |       (e)                                          |
|FISHER EXACT           |                       (e)           P=0.245        |                       (e)             (e)          |
|=================================================================================================================================|
|                                                                                                                                 |
|Uterus                                                                                                                           |
|     Polyp Stromal                                                                                                               |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |                                                    |       #               #               #            |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |                                                    |     1/68 (1%)       1/70 (1%)       2/70 (3%)      |
|ADJUSTED (b)           |                                                    |      2.8%            2.0%            4.0%          |
|INTERIM SACRIFICE 1 (c)|                                                    |     0/5 (0%)        0/5 (0%)        1/5 (20%)      |
|INTERIM SACRIFICE 2 (c)|                                                    |     0/5 (0%)        0/5 (0%)        0/5 (0%)       |
|TERMINAL (d)           |                                                    |     1/36 (3%)       0/34 (0%)       1/38 (3%)      |
|FIRST INCIDENCE (DAYS) |                                                    |      733 (T)         623             197 (I)       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |                                                    |     P=0.390         P=0.759         P=0.513        |
|INCIDENTAL TUMOR       |                                                    |     P=0.436         P=0.747N        P=0.513        |
|LOGISTIC REGRESSION    |                                                    |     P=0.390         P=0.760N        P=0.516        |
|COCHRAN-ARMITAGE       |                                                    |     P=0.387                                        |
|FISHER EXACT           |                                                    |                     P=0.745N        P=0.511        |
|=================================================================================================================================|
         DATE: 05/19/95                     EXPERIMENT: 05107 TEST: 06                                                 PAGE  11
                              STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- NICKEL SUBSULFIDE
                                                 MALE TERMINAL SACRIFICE AT 106 WEEKS
                                                 FEMALE TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |      0.0MG/M3        0.6MG/M3        1.2MG/M3      |      0.0MG/M3        0.6MG/M3        1.2MG/M3      |
|                       |      LUNG TOX        LUNG TOX        LUNG TOX      |      LUNG TOX        LUNG TOX        LUNG TOX      |
|=================================================================================================================================|
|                                                                                                                                 |
|All Organs                                                                                                                       |
|     Hemangioma                                                                                                                  |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |       #               #               #            |       #               #               #            |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |     1/71 (1%)       1/70 (1%)       2/70 (3%)      |     2/68 (3%)       0/70 (0%)       1/70 (1%)      |
|ADJUSTED (b)           |      3.8%            3.7%            7.4%          |      4.4%            0.0%            2.6%          |
|INTERIM SACRIFICE 1 (c)|     0/5 (0%)        0/5 (0%)        0/5 (0%)       |     0/5 (0%)        0/5 (0%)        0/5 (0%)       |
|INTERIM SACRIFICE 2 (c)|     0/5 (0%)        0/5 (0%)        0/5 (0%)       |     1/5 (20%)       0/5 (0%)        0/5 (0%)       |
|TERMINAL (d)           |     1/26 (4%)       0/25 (0%)       1/25 (4%)      |     1/36 (3%)       0/34 (0%)       1/38 (3%)      |
|FIRST INCIDENCE (DAYS) |      737 (T)         716             713           |      477 (I)         ---             733 (T)       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |     P=0.374         P=0.756         P=0.491        |     P=0.353N        P=0.246N        P=0.487N       |
|INCIDENTAL TUMOR       |     P=0.456         P=0.756         P=0.546        |     P=0.353N        P=0.246N        P=0.487N       |
|LOGISTIC REGRESSION    |     P=0.388         P=0.757         P=0.510        |     P=0.354N        P=0.230N        P=0.491N       |
|COCHRAN-ARMITAGE       |     P=0.374                                        |     P=0.353N                                       |
|FISHER EXACT           |                     P=0.748         P=0.495        |                     P=0.241N        P=0.489N       |
|=================================================================================================================================|
|                                                                                                                                 |
|All Organs                                                                                                                       |
|     Hemangiosarcoma                                                                                                             |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |       #               #               #            |       #               #               #            |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |     1/71 (1%)       3/70 (4%)       2/70 (3%)      |     3/68 (4%)       4/70 (6%)       4/70 (6%)      |
|ADJUSTED (b)           |      1.8%           10.9%            6.5%          |      7.8%           10.1%            9.4%          |
|INTERIM SACRIFICE 1 (c)|     0/5 (0%)        0/5 (0%)        0/5 (0%)       |     0/5 (0%)        0/5 (0%)        0/5 (0%)       |
|INTERIM SACRIFICE 2 (c)|     0/5 (0%)        0/5 (0%)        0/5 (0%)       |     0/5 (0%)        0/5 (0%)        1/5 (20%)      |
|TERMINAL (d)           |     0/26 (0%)       2/25 (8%)       1/25 (4%)      |     2/36 (6%)       2/34 (6%)       3/38 (8%)      |
|FIRST INCIDENCE (DAYS) |      480             671             661           |      680             623             477 (I)       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |     P=0.390         P=0.291         P=0.493        |     P=0.449         P=0.482         P=0.521        |
|INCIDENTAL TUMOR       |     P=0.481         P=0.301         P=0.584        |     P=0.434         P=0.510         P=0.487        |
|LOGISTIC REGRESSION    |     P=0.394         P=0.291         P=0.493        |     P=0.439         P=0.500         P=0.514        |
|COCHRAN-ARMITAGE       |     P=0.394                                        |     P=0.440                                        |
|FISHER EXACT           |                     P=0.304         P=0.495        |                     P=0.516         P=0.516        |
|=================================================================================================================================|
         DATE: 05/19/95                     EXPERIMENT: 05107 TEST: 06                                                 PAGE  12
                              STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- NICKEL SUBSULFIDE
                                                 MALE TERMINAL SACRIFICE AT 106 WEEKS
                                                 FEMALE TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |      0.0MG/M3        0.6MG/M3        1.2MG/M3      |      0.0MG/M3        0.6MG/M3        1.2MG/M3      |
|                       |      LUNG TOX        LUNG TOX        LUNG TOX      |      LUNG TOX        LUNG TOX        LUNG TOX      |
|=================================================================================================================================|
|                                                                                                                                 |
|All Organs                                                                                                                       |
|     Hemangiosarcoma or Hemangioma                                                                                               |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |       #               #               #            |       #               #               #            |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |     2/71 (3%)       4/70 (6%)       4/70 (6%)      |     5/68 (7%)       4/70 (6%)       5/70 (7%)      |
|ADJUSTED (b)           |      5.6%           14.2%           13.6%          |     12.0%           10.1%           12.0%          |
|INTERIM SACRIFICE 1 (c)|     0/5 (0%)        0/5 (0%)        0/5 (0%)       |     0/5 (0%)        0/5 (0%)        0/5 (0%)       |
|INTERIM SACRIFICE 2 (c)|     0/5 (0%)        0/5 (0%)        0/5 (0%)       |     1/5 (20%)       0/5 (0%)        1/5 (20%)      |
|TERMINAL (d)           |     1/26 (4%)       2/25 (8%)       2/25 (8%)      |     3/36 (8%)       2/34 (6%)       4/38 (11%)     |
|FIRST INCIDENCE (DAYS) |      480             671             661           |      477 (I)         623             477 (I)       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |     P=0.268         P=0.323         P=0.329        |     P=0.541N        P=0.520N        P=0.605N       |
|INCIDENTAL TUMOR       |     P=0.379         P=0.329         P=0.427        |     P=0.554N        P=0.495N        P=0.625        |
|LOGISTIC REGRESSION    |     P=0.274         P=0.317         P=0.332        |     P=0.552N        P=0.496N        P=0.613N       |
|COCHRAN-ARMITAGE       |     P=0.270                                        |     P=0.549N                                       |
|FISHER EXACT           |                     P=0.334         P=0.334        |                     P=0.482N        P=0.609N       |
|=================================================================================================================================|
|                                                                                                                                 |
|All Organs                                                                                                                       |
|     Histiocytic Sarcoma                                                                                                         |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |       #               #               #            |       #               #               #            |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |     0/71 (0%)       0/70 (0%)       0/70 (0%)      |     2/68 (3%)       2/70 (3%)       2/70 (3%)      |
|ADJUSTED (b)           |      0.0%            0.0%            0.0%          |      4.4%            5.1%            3.5%          |
|INTERIM SACRIFICE 1 (c)|     0/5 (0%)        0/5 (0%)        0/5 (0%)       |     0/5 (0%)        0/5 (0%)        0/5 (0%)       |
|INTERIM SACRIFICE 2 (c)|     0/5 (0%)        0/5 (0%)        0/5 (0%)       |     0/5 (0%)        0/5 (0%)        0/5 (0%)       |
|TERMINAL (d)           |     0/26 (0%)       0/25 (0%)       0/25 (0%)      |     1/36 (3%)       1/34 (3%)       0/38 (0%)      |
|FIRST INCIDENCE (DAYS) |      ---             ---             ---           |      419             655             445           |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |       (e)             (e)             (e)          |     P=0.583N        P=0.681         P=0.674N       |
|INCIDENTAL TUMOR       |       (e)             (e)             (e)          |     P=0.591         P=0.675N        P=0.697N       |
|LOGISTIC REGRESSION    |       (e)             (e)             (e)          |     P=0.588N        P=0.686N        P=0.678N       |
|COCHRAN-ARMITAGE       |       (e)                                          |     P=0.589N                                       |
|FISHER EXACT           |                       (e)             (e)          |                     P=0.679N        P=0.679N       |
|=================================================================================================================================|
         DATE: 05/19/95                     EXPERIMENT: 05107 TEST: 06                                                 PAGE  13
                              STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- NICKEL SUBSULFIDE
                                                 MALE TERMINAL SACRIFICE AT 106 WEEKS
                                                 FEMALE TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |      0.0MG/M3        0.6MG/M3        1.2MG/M3      |      0.0MG/M3        0.6MG/M3        1.2MG/M3      |
|                       |      LUNG TOX        LUNG TOX        LUNG TOX      |      LUNG TOX        LUNG TOX        LUNG TOX      |
|=================================================================================================================================|
|                                                                                                                                 |
|All Organs                                                                                                                       |
|     Malignant Lymphoma And Histiocytic Sarcoma                                                                                  |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |       #               #               #            |       #               #               #            |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |     1/71 (1%)       1/70 (1%)       0/70 (0%)      |     7/68 (10%)      9/70 (13%)      8/70 (11%)     |
|ADJUSTED (b)           |      3.8%            4.0%            0.0%          |     17.2%           20.1%           17.6%          |
|INTERIM SACRIFICE 1 (c)|     0/5 (0%)        0/5 (0%)        0/5 (0%)       |     0/5 (0%)        0/5 (0%)        0/5 (0%)       |
|INTERIM SACRIFICE 2 (c)|     0/5 (0%)        0/5 (0%)        0/5 (0%)       |     0/5 (0%)        0/5 (0%)        0/5 (0%)       |
|TERMINAL (d)           |     1/26 (4%)       1/25 (4%)       0/25 (0%)      |     5/36 (14%)      3/34 (9%)       4/38 (11%)     |
|FIRST INCIDENCE (DAYS) |      737 (T)         737 (T)         ---           |      419             425             445           |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |     P=0.340N        P=0.754         P=0.508N       |     P=0.485         P=0.375         P=0.537        |
|INCIDENTAL TUMOR       |     P=0.340N        P=0.754         P=0.508N       |     P=0.354         P=0.427         P=0.453        |
|LOGISTIC REGRESSION    |     P=0.339N        P=0.754         P=0.508N       |     P=0.468         P=0.405         P=0.521        |
|COCHRAN-ARMITAGE       |     P=0.335N                                       |     P=0.471                                        |
|FISHER EXACT           |                     P=0.748         P=0.504N       |                     P=0.420         P=0.524        |
|=================================================================================================================================|
|                                                                                                                                 |
|All Organs                                                                                                                       |
|     Malignant Lymphoma: Histiocytic, Lymphocytic, Mixed, NOS, or Undifferentiated                                               |
|     Cell Type                                                                                                                   |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |       #               #               #            |       #               #               #            |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |     1/71 (1%)       1/70 (1%)       0/70 (0%)      |     5/68 (7%)       7/70 (10%)      6/70 (9%)      |
|ADJUSTED (b)           |      3.8%            4.0%            0.0%          |     13.1%           15.6%           14.6%          |
|INTERIM SACRIFICE 1 (c)|     0/5 (0%)        0/5 (0%)        0/5 (0%)       |     0/5 (0%)        0/5 (0%)        0/5 (0%)       |
|INTERIM SACRIFICE 2 (c)|     0/5 (0%)        0/5 (0%)        0/5 (0%)       |     0/5 (0%)        0/5 (0%)        0/5 (0%)       |
|TERMINAL (d)           |     1/26 (4%)       1/25 (4%)       0/25 (0%)      |     4/36 (11%)      2/34 (6%)       4/38 (11%)     |
|FIRST INCIDENCE (DAYS) |      737 (T)         737 (T)         ---           |      679             425             653           |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |     P=0.340N        P=0.754         P=0.508N       |     P=0.474         P=0.365         P=0.532        |
|INCIDENTAL TUMOR       |     P=0.340N        P=0.754         P=0.508N       |     P=0.344         P=0.406         P=0.443        |
|LOGISTIC REGRESSION    |     P=0.339N        P=0.754         P=0.508N       |     P=0.458         P=0.387         P=0.522        |
|COCHRAN-ARMITAGE       |     P=0.335N                                       |     P=0.461                                        |
|FISHER EXACT           |                     P=0.748         P=0.504N       |                     P=0.403         P=0.520        |
|=================================================================================================================================|
         DATE: 05/19/95                     EXPERIMENT: 05107 TEST: 06                                                 PAGE  14
                              STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- NICKEL SUBSULFIDE
                                                 MALE TERMINAL SACRIFICE AT 106 WEEKS
                                                 FEMALE TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |      0.0MG/M3        0.6MG/M3        1.2MG/M3      |      0.0MG/M3        0.6MG/M3        1.2MG/M3      |
|                       |      LUNG TOX        LUNG TOX        LUNG TOX      |      LUNG TOX        LUNG TOX        LUNG TOX      |
|=================================================================================================================================|
|                                                                                                                                 |
|All Organs                                                                                                                       |
|     Benign Tumors                                                                                                               |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |       #               #               #            |       #               #               #            |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |    28/71 (39%)     17/70 (24%)     20/70 (29%)     |    29/68 (43%)     22/70 (31%)     21/70 (30%)     |
|ADJUSTED (b)           |     71.9%           43.2%           53.8%          |     65.0%           49.4%           45.5%          |
|INTERIM SACRIFICE 1 (c)|     0/5 (0%)        0/5 (0%)        0/5 (0%)       |     0/5 (0%)        0/5 (0%)        1/5 (20%)      |
|INTERIM SACRIFICE 2 (c)|     1/5 (20%)       2/5 (40%)       1/5 (20%)      |     2/5 (40%)       0/5 (0%)        0/5 (0%)       |
|TERMINAL (d)           |    16/26 (62%)      6/25 (24%)     10/25 (40%)     |    21/36 (58%)     13/34 (38%)     14/38 (37%)     |
|FIRST INCIDENCE (DAYS) |      313             475             144           |      477 (I)         116             197 (I)       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |     P=0.108N        P=0.064N        P=0.127N       |     P=0.068N        P=0.194N        P=0.076N       |
|INCIDENTAL TUMOR       |     P=0.083N        P=0.043N*       P=0.118N       |     P=0.070N        P=0.132N        P=0.101N       |
|LOGISTIC REGRESSION    |     P=0.091N        P=0.043N*       P=0.111N       |     P=0.066N        P=0.128N        P=0.078N       |
|COCHRAN-ARMITAGE       |     P=0.095N                                       |     P=0.071N                                       |
|FISHER EXACT           |                     P=0.040N*       P=0.118N       |                     P=0.117N        P=0.086N       |
|=================================================================================================================================|
|                                                                                                                                 |
|All Organs                                                                                                                       |
|     Malignant Tumors                                                                                                            |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |       #               #               #            |       #               #               #            |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |    21/71 (30%)     23/70 (33%)     21/70 (30%)     |    26/68 (38%)     27/70 (39%)     23/70 (33%)     |
|ADJUSTED (b)           |     49.0%           55.1%           48.8%          |     54.7%           51.1%           43.6%          |
|INTERIM SACRIFICE 1 (c)|     0/5 (0%)        0/5 (0%)        0/5 (0%)       |     0/5 (0%)        0/5 (0%)        0/5 (0%)       |
|INTERIM SACRIFICE 2 (c)|     0/5 (0%)        0/5 (0%)        1/5 (20%)      |     0/5 (0%)        0/5 (0%)        1/5 (20%)      |
|TERMINAL (d)           |     8/26 (31%)      9/25 (36%)      6/25 (24%)     |    15/36 (42%)      9/34 (26%)     10/38 (26%)     |
|FIRST INCIDENCE (DAYS) |      434             415             450           |      419             206             445           |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |     P=0.512         P=0.370         P=0.553        |     P=0.295N        P=0.455         P=0.317N       |
|INCIDENTAL TUMOR       |     P=0.482         P=0.342         P=0.523        |     P=0.355N        P=0.559N        P=0.360N       |
|LOGISTIC REGRESSION    |     P=0.352         P=0.369         P=0.380        |     P=0.286N        P=0.519         P=0.306N       |
|COCHRAN-ARMITAGE       |     P=0.514                                        |     P=0.284N                                       |
|FISHER EXACT           |                     P=0.406         P=0.551        |                     P=0.554         P=0.315N       |
|=================================================================================================================================|
         DATE: 05/19/95                     EXPERIMENT: 05107 TEST: 06                                                 PAGE  15
                              STATISTICAL ANALYSIS OF PRIMARY TUMORS IN MICE(B6C3F1) -- NICKEL SUBSULFIDE
                                                 MALE TERMINAL SACRIFICE AT 106 WEEKS
                                                 FEMALE TERMINAL SACRIFICE AT 105 WEEKS
|=================================================================================================================================|
|                       |                                                    |                                                    |
|                       |                       MALES                        |                      FEMALES                       |
|                       |                                                    |                                                    |
|DOSE                   |      0.0MG/M3        0.6MG/M3        1.2MG/M3      |      0.0MG/M3        0.6MG/M3        1.2MG/M3      |
|                       |      LUNG TOX        LUNG TOX        LUNG TOX      |      LUNG TOX        LUNG TOX        LUNG TOX      |
|=================================================================================================================================|
|                                                                                                                                 |
|All Organs                                                                                                                       |
|     Malignant and Benign Tumors                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES            |       #               #               #            |       #               #               #            |
|-----------            |                                                    |                                                    |
|OVERALL (a)            |    41/71 (58%)     33/70 (47%)     36/70 (51%)     |    44/68 (65%)     39/70 (56%)     39/70 (56%)     |
|ADJUSTED (b)           |     84.1%           68.1%           77.0%          |     86.0%           70.3%           70.5%          |
|INTERIM SACRIFICE 1 (c)|     0/5 (0%)        0/5 (0%)        0/5 (0%)       |     0/5 (0%)        0/5 (0%)        1/5 (20%)      |
|INTERIM SACRIFICE 2 (c)|     1/5 (20%)       2/5 (40%)       1/5 (20%)      |     2/5 (40%)       0/5 (0%)        1/5 (20%)      |
|TERMINAL (d)           |    19/26 (73%)     11/25 (44%)     15/25 (60%)     |    29/36 (81%)     18/34 (53%)     22/38 (58%)     |
|FIRST INCIDENCE (DAYS) |      313             415             144           |      419             116             197 (I)       |
|-----------------------|                                                    |                                                    |
|STATISTICAL TESTS (f)  |                                                    |                                                    |
|-----------------------|                                                    |                                                    |
|LIFE TABLE             |     P=0.303N        P=0.239N        P=0.321N       |     P=0.190N        P=0.356N        P=0.196N       |
|INCIDENTAL TUMOR       |     P=0.215N        P=0.154N        P=0.276N       |     P=0.194N        P=0.158N        P=0.215N       |
|LOGISTIC REGRESSION    |     P=0.313N        P=0.169N        P=0.296N       |     P=0.156N        P=0.205N        P=0.170N       |
|COCHRAN-ARMITAGE       |     P=0.251N                                       |     P=0.163N                                       |
|FISHER EXACT           |                     P=0.137N        P=0.280N       |                     P=0.183N        P=0.183N       |
|=================================================================================================================================|
 (a)  Number of tumor-bearing animals / number of animals examined at site.
 (b)  Kaplan-Meier estimated lifetime tumor incidence after adjustment for 
      intercurrent mortality.
 (c)  Observed incidence at interim kill.
          Male interim sacrifices(days):   196  476
          Female interim sacrifices(days): 197  477
 (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).