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TDMS Study 05135-07 Pathology Tables

NTP                                        STATISTICAL ANALYSIS OF PRIMARY TUMORS                              REPORT: PEIRPT08
LAB: Battelle Northwest                                         ISOPRENE                                       DATE: 10/01/97

EXPERIMENT: 05135 TEST: 07                                                                                     TIME: 13:24:18
TEST TYPE:  CHRONIC                             CAGES FROM 0000 TO LAST CAGE                                   PAGE:
CONT: NO1-ES-25335                              ROUTE: RESPIRATORY EXPOSURE WHOLE BODY                         NTP C#: 61825B
PATHOLOGIST: GRUMBEIN, S.                                                                                      CAS: 78-79-5
                

Rats(FISCHER344)
-----------------------------
FOR ALL DOSES THE TUMOR RATES IN THE FOLLOWING TISSUES/ORGANS ARE BASED ON NUMBER OF TISSUES EXAMINED.
IN OTHER TISSUES/ORGANS, RATES ARE BASED ON NUMBER OF ANIMALS NECROPSIED.

                                                 ----------------
                                                 Adrenal Gland
                                                 Adrenal Medulla
                                                 Bone Marrow
                                                 Brain
                                                 Clitoral Gland
                                                 Clitoral/Preputial Gland
                                                 Epididymis
                                                 Heart
                                                 Islets, Pancreatic
                                                 Kidney
                                                 Liver
                                                 Lung
                                                 Nose
                                                 Ovary
                                                 Pancreas
                                                 Parathyroid Gland
                                                 Pituitary Gland
                                                 Preputial Gland
                                                 Prostate
                                                 Salivary Glands
                                                 Spleen
                                                 Testes
                                                 Thymus
                                                 Thyroid Gland
                                                 Urinary Bladder
NTP                                        STATISTICAL ANALYSIS OF PRIMARY TUMORS                              REPORT: PEIRPT08   
LAB: Battelle Northwest                                         ISOPRENE                                       DATE: 10/01/97     
EXPERIMENT: 05135 TEST: 07                                                                                     TIME: 13:24:18     
TEST TYPE:  CHRONIC                             CAGES FROM 0000 TO LAST CAGE                                   PAGE:              
CONT: NO1-ES-25335                              ROUTE: RESPIRATORY EXPOSURE WHOLE BODY                         NTP C#: 61825B     
PATHOLOGIST: GRUMBEIN, S.                                                                                      CAS: 78-79-5       



SUMMARY OF STATISTICALLY SIGNIFICANT (P<=.05) RESULTS
IN THE ANALYSIS OF                     ISOPRENE
===============================================================

Male Rats
------------
Organ                                 Morphology
-----                                 ----------
Kidney: Renal Tubule                   Adenoma
                                       Carcinoma or Adenoma
Lung                                   Alveolar/Bronchiolar Carcinoma
                                       Alveolar/Bronchiolar Carcinoma or Alveolar/Bronchiolar Adenoma
Mammary Gland                          Fibroadenoma
                                       Fibroma, Fibroadenoma, Carcinoma, or Adenoma
Pituitary Gland: Pars Distalis or Unspecified Site
                                       Adenoma
                                       Carcinoma or Adenoma
Testes                                 Adenoma
===============================================================
Female Rats
------------
Organ                                  Morphology
-----                                  ----------
Mammary Gland                          Fibroadenoma
                                       Fibroma, Fibroadenoma, Carcinoma, or Adenoma
Thyroid Gland: C-Cell                  Carcinoma or Adenoma
===============================================================
       Date:  10/01/97                           EXPERIMENT: 05135 TEST: 07                                            Page 1
                     Statistical Analysis of Primary Tumors in Rats(FISCHER344)        -                      ISOPRENE
                                         Terminal Sacrifice at 104 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Adrenal Cortex                                                                                                                   |
|     Adenoma                                                                                                                     |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     1/50 (2%)    0/50 (0%)    0/50 (0%)    0/50 (0%)   |2/50 (4%)    1/50 (2%)    2/50 (4%)    1/50 (2%)    |
|POLY-3 ADJUSTED (b)|     2.7%         0.0%         0.0%         0.0%        |4.7%         2.3%         4.8%         2.5%         |
|TERMINAL (d)       |     0/18 (0%)    0/16 (0%)    0/15 (0%)    0/15 (0%)   |2/29 (7%)    1/30 (3%)    2/28 (7%)    1/27 (4%)    |
|FIRST INCIDENCE    |     604          ---          ---          ---         |734 (T)      734 (T)      734 (T)      734 (T)      |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.638N     P=0.489N     P=0.500N     P=0.478N    |P=0.526N     P=0.488N     P=0.684      P=0.525N     |
|POLY 3             |     P=0.656N     P=0.498N     P=0.501N     P=0.500N    |P=0.518N     P=0.489N     P=0.687      P=0.516N     |
|POLY 1.5           |     P=0.659N     P=0.497N     P=0.498N     P=0.500N    |P=0.511N     P=0.493N     P=0.688      P=0.512N     |
|POLY 6             |     P=0.649N     P=0.504N     P=0.509N     P=0.503N    |P=0.523N     P=0.485N     P=0.688      P=0.519N     |
|LOGISTIC REGRESSION|     P=0.645N     P=0.515N     P=0.514N     P=0.497N    |P=0.526N     P=0.488N     P=0.684      P=0.525N     |
|COCH-ARM / FISHERS |     P=0.657N     P=0.500N     P=0.500N     P=0.500N    |P=0.494N     P=0.500N     P=0.691N     P=0.500N     |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Adrenal Medulla                                                                                                                  |
|     Pheochromocytoma Benign                                                                                                     |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     18/50 (36%)  15/50 (30%)  20/50 (40%)  18/50 (36%) |1/50 (2%)    5/50 (10%)   4/50 (8%)    3/50 (6%)    |
|POLY-3 ADJUSTED (b)|     46.3%        37.0%        49.7%        44.8%       |2.4%         11.4%        9.5%         7.3%         |
|TERMINAL (d)       |     10/18 (56%)  6/16 (38%)   9/15 (60%)   5/15 (33%)  |1/29 (3%)    5/30 (17%)   2/28 (7%)    1/27 (4%)    |
|FIRST INCIDENCE    |     539          538          510          548         |734 (T)      734 (T)      638          652          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.455      P=0.431N     P=0.271      P=0.465     |P=0.610      P=0.108      P=0.175      P=0.281      |
|POLY 3             |     P=0.530      P=0.264N     P=0.469      P=0.535N    |P=0.617N     P=0.108      P=0.175      P=0.291      |
|POLY 1.5           |     P=0.500      P=0.284N     P=0.462      P=0.565N    |P=0.610N     P=0.106      P=0.175      P=0.294      |
|POLY 6             |     P=0.569      P=0.254N     P=0.450      P=0.511N    |P=0.621N     P=0.109      P=0.177      P=0.290      |
|LOGISTIC REGRESSION|     P=0.521      P=0.304N     P=0.418      P=0.560N    |P=0.617      P=0.108      P=0.173      P=0.287      |
|COCH-ARM / FISHERS |     P=0.509      P=0.335N     P=0.418      P=0.582N    |P=0.590N     P=0.102      P=0.181      P=0.309      |
|=================================================================================================================================|
       Date:  10/01/97                           EXPERIMENT: 05135 TEST: 07                                            Page 2
                     Statistical Analysis of Primary Tumors in Rats(FISCHER344)       -                      ISOPRENE
                                         Terminal Sacrifice at 104 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Adrenal Medulla                                                                                                                  |
|     Pheochromocytoma Malignant                                                                                                  |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     3/50 (6%)    1/50 (2%)    1/50 (2%)    0/50 (0%)   |1/50 (2%)    0/50 (0%)    0/50 (0%)    0/50 (0%)    |
|POLY-3 ADJUSTED (b)|     8.2%         2.6%         2.7%         0.0%        |2.4%         0.0%         0.0%         0.0%         |
|TERMINAL (d)       |     2/18 (11%)   0/16 (0%)    1/15 (7%)    0/15 (0%)   |1/29 (3%)    0/30 (0%)    0/28 (0%)    0/27 (0%)    |
|FIRST INCIDENCE    |     721          592          733 (T)      ---         |734 (T)      ---          ---          ---          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.194N     P=0.351N     P=0.378N     P=0.153N    |P=0.671N     P=0.493N     P=0.507N     P=0.514N     |
|POLY 3             |     P=0.182N     P=0.293N     P=0.302N     P=0.115N    |P=0.662N     P=0.493N     P=0.504N     P=0.509N     |
|POLY 1.5           |     P=0.185N     P=0.295N     P=0.300N     P=0.117N    |P=0.659N     P=0.496N     P=0.504N     P=0.507N     |
|POLY 6             |     P=0.179N     P=0.295N     P=0.312N     P=0.116N    |P=0.663N     P=0.492N     P=0.504N     P=0.511N     |
|LOGISTIC REGRESSION|     P=0.180N     P=0.301N     P=0.363N     P=0.136N    |P=0.671N     (e)          (e)          (e)          |
|COCH-ARM / FISHERS |     P=0.182N     P=0.309N     P=0.309N     P=0.121N    |P=0.657N     P=0.500N     P=0.500N     P=0.500N     |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Adrenal Medulla                                                                                                                  |
|     Pheochromocytoma: Benign, Complex, Malignant, NOS                                                                           |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     20/50 (40%)  16/50 (32%)  20/50 (40%)  18/50 (36%) |2/50 (4%)    5/50 (10%)   4/50 (8%)    3/50 (6%)    |
|POLY-3 ADJUSTED (b)|     51.4%        39.0%        49.7%        44.8%       |4.7%         11.4%        9.5%         7.3%         |
|TERMINAL (d)       |     11/18 (61%)  6/16 (38%)   9/15 (60%)   5/15 (33%)  |2/29 (7%)    5/30 (17%)   2/28 (7%)    1/27 (4%)    |
|FIRST INCIDENCE    |     539          538          510          548         |734 (T)      734 (T)      638          652          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.556N     P=0.373N     P=0.396      P=0.546N    |P=0.561N     P=0.226      P=0.327      P=0.466      |
|POLY 3             |     P=0.496N     P=0.179N     P=0.530N     P=0.351N    |P=0.541N     P=0.229      P=0.332      P=0.483      |
|POLY 1.5           |     P=0.519N     P=0.206N     P=0.536N     P=0.389N    |P=0.534N     P=0.224      P=0.331      P=0.486      |
|POLY 6             |     P=0.465N     P=0.158N     P=0.554N     P=0.320N    |P=0.546N     P=0.231      P=0.336      P=0.481      |
|LOGISTIC REGRESSION|     P=0.490N     P=0.232N     P=0.585N     P=0.384N    |P=0.557N     P=0.226      P=0.327      P=0.475      |
|COCH-ARM / FISHERS |     P=0.503N     P=0.266N     P=0.581N     P=0.418N    |P=0.513N     P=0.218      P=0.339      P=0.500      |
|=================================================================================================================================|
       Date:  10/01/97                           EXPERIMENT: 05135 TEST: 07                                            Page 3
                     Statistical Analysis of Primary Tumors in Rats(FISCHER344)       -                      ISOPRENE
                                         Terminal Sacrifice at 104 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Clitoral/Preputial Gland                                                                                                         |
|     Adenoma                                                                                                                     |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     2/50 (4%)    1/50 (2%)    3/50 (6%)    3/50 (6%)   |3/47 (6%)    5/48 (10%)   5/46 (11%)   6/48 (13%)   |
|POLY-3 ADJUSTED (b)|     5.4%         2.7%         8.1%         8.1%        |7.4%         11.8%        13.1%        15.4%        |
|TERMINAL (d)       |     1/18 (6%)    1/16 (6%)    3/15 (20%)   2/15 (13%)  |2/27 (7%)    4/29 (14%)   4/26 (15%)   5/26 (19%)   |
|FIRST INCIDENCE    |     597          733 (T)      733 (T)      727         |596          670          708          681          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.351      P=0.521N     P=0.427      P=0.445     |P=0.271      P=0.398      P=0.342      P=0.223      |
|POLY 3             |     P=0.390      P=0.497N     P=0.497      P=0.501     |P=0.284      P=0.379      P=0.322      P=0.220      |
|POLY 1.5           |     P=0.387      P=0.495N     P=0.504      P=0.500     |P=0.297      P=0.375      P=0.328      P=0.229      |
|POLY 6             |     P=0.389      P=0.508N     P=0.479      P=0.493     |P=0.273      P=0.382      P=0.317      P=0.213      |
|LOGISTIC REGRESSION|     P=0.388      P=0.495N     P=0.484      P=0.499     |P=0.276      P=0.381      P=0.326      P=0.222      |
|COCH-ARM / FISHERS |     P=0.391      P=0.500N     P=0.500      P=0.500     |P=0.328      P=0.369      P=0.345      P=0.254      |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Clitoral/Preputial Gland                                                                                                         |
|     Carcinoma                                                                                                                   |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     3/50 (6%)    2/50 (4%)    2/50 (4%)    0/50 (0%)   |2/47 (4%)    5/48 (10%)   2/46 (4%)    2/48 (4%)    |
|POLY-3 ADJUSTED (b)|     8.2%         5.2%         5.2%         0.0%        |5.0%         11.7%        5.2%         5.1%         |
|TERMINAL (d)       |     3/18 (17%)   0/16 (0%)    0/15 (0%)    0/15 (0%)   |1/27 (4%)    3/29 (10%)   1/26 (4%)    1/26 (4%)    |
|FIRST INCIDENCE    |     733 (T)      398          454          ---         |714          482          617          594          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.132N     P=0.541N     P=0.542N     P=0.151N    |P=0.444N     P=0.239      P=0.673      P=0.674      |
|POLY 3             |     P=0.123N     P=0.480N     P=0.481N     P=0.115N    |P=0.422N     P=0.242      P=0.679      P=0.686      |
|POLY 1.5           |     P=0.125N     P=0.484N     P=0.484N     P=0.117N    |P=0.416N     P=0.236      P=0.679      P=0.689      |
|POLY 6             |     P=0.122N     P=0.483N     P=0.485N     P=0.115N    |P=0.426N     P=0.246      P=0.680      P=0.685      |
|LOGISTIC REGRESSION|     P=0.112N     P=0.495N     P=0.503N     (e)         |P=0.405N     P=0.226      P=0.680      P=0.692      |
|COCH-ARM / FISHERS |     P=0.120N     P=0.500N     P=0.500N     P=0.121N    |P=0.400N     P=0.226      P=0.683      P=0.684N     |
|=================================================================================================================================|
       Date:  10/01/97                           EXPERIMENT: 05135 TEST: 07                                            Page 4
                     Statistical Analysis of Primary Tumors in Rats(FISCHER344)       -                      ISOPRENE
                                         Terminal Sacrifice at 104 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Clitoral/Preputial Gland                                                                                                         |
|     Carcinoma or Adenoma                                                                                                        |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     5/50 (10%)   3/50 (6%)    5/50 (10%)   3/50 (6%)   |5/47 (11%)   10/48 (21%)  7/46 (15%)   8/48 (17%)   |
|POLY-3 ADJUSTED (b)|     13.5%        7.8%         13.1%        8.1%        |12.3%        23.3%        18.2%        20.3%        |
|TERMINAL (d)       |     4/18 (22%)   1/16 (6%)    3/15 (20%)   2/15 (13%)  |3/27 (11%)   7/29 (24%)   5/26 (19%)   6/26 (23%)   |
|FIRST INCIDENCE    |     597          398          454          727         |596          482          617          594          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.422N     P=0.401N     P=0.551      P=0.436N    |P=0.426      P=0.166      P=0.357      P=0.251      |
|POLY 3             |     P=0.393N     P=0.336N     P=0.614N     P=0.353N    |P=0.449      P=0.153      P=0.341      P=0.253      |
|POLY 1.5           |     P=0.395N     P=0.339N     P=0.613N     P=0.356N    |P=0.464      P=0.148      P=0.345      P=0.262      |
|POLY 6             |     P=0.395N     P=0.345N     P=0.628N     P=0.361N    |P=0.438      P=0.156      P=0.338      P=0.246      |
|LOGISTIC REGRESSION|     P=0.382N     P=0.347N     P=0.626N     P=0.368N    |P=0.451      P=0.146      P=0.342      P=0.254      |
|COCH-ARM / FISHERS |     P=0.381N     P=0.357N     P=0.630N     P=0.357N    |P=0.505      P=0.140      P=0.364      P=0.290      |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Islets, Pancreatic                                                                                                               |
|     Adenoma                                                                                                                     |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     1/50 (2%)    2/50 (4%)    5/50 (10%)   1/49 (2%)   |1/49 (2%)    2/50 (4%)    0/50 (0%)    0/50 (0%)    |
|POLY-3 ADJUSTED (b)|     2.7%         5.3%         13.3%        2.7%        |2.4%         4.6%         0.0%         0.0%         |
|TERMINAL (d)       |     1/18 (6%)    1/16 (6%)    3/15 (20%)   0/15 (0%)   |1/29 (3%)    2/30 (7%)    0/28 (0%)    0/27 (0%)    |
|FIRST INCIDENCE    |     733 (T)      592          566          621         |734 (T)      734 (T)      ---          ---          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.352N     P=0.479      P=0.074      P=0.747     |P=0.336N     P=0.512      P=0.507N     P=0.514N     |
|POLY 3             |     P=0.323N     P=0.511      P=0.103      P=0.757N    |P=0.323N     P=0.517      P=0.501N     P=0.506N     |
|POLY 1.5           |     P=0.332N     P=0.510      P=0.105      P=0.761N    |P=0.321N     P=0.513      P=0.500N     P=0.503N     |
|POLY 6             |     P=0.318N     P=0.508      P=0.097      P=0.757N    |P=0.325N     P=0.519      P=0.502N     P=0.509N     |
|LOGISTIC REGRESSION|     P=0.331N     P=0.505      P=0.094      P=0.763     |P=0.336N     P=0.512      (e)          (e)          |
|COCH-ARM / FISHERS |     P=0.340N     P=0.500      P=0.102      P=0.747     |P=0.317N     P=0.508      P=0.495N     P=0.495N     |
|=================================================================================================================================|
       Date:  10/01/97                           EXPERIMENT: 05135 TEST: 07                                            Page 5
                     Statistical Analysis of Primary Tumors in Rats(FISCHER344)       -                      ISOPRENE
                                         Terminal Sacrifice at 104 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Islets, Pancreatic                                                                                                               |
|     Carcinoma                                                                                                                   |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     2/50 (4%)    0/50 (0%)    1/50 (2%)    1/49 (2%)   |0/49 (0%)    0/50 (0%)    2/50 (4%)    1/50 (2%)    |
|POLY-3 ADJUSTED (b)|     5.5%         0.0%         2.7%         2.7%        |0.0%         0.0%         4.8%         2.5%         |
|TERMINAL (d)       |     2/18 (11%)   0/16 (0%)    0/15 (0%)    1/15 (7%)   |0/29 (0%)    0/30 (0%)    1/28 (4%)    0/27 (0%)    |
|FIRST INCIDENCE    |     733 (T)      ---          655          733 (T)     |---          ---          727          714          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.703      P=0.263N     P=0.535N     P=0.565N    |P=0.526      (e)          P=0.225      P=0.474      |
|POLY 3             |     P=0.698N     P=0.232N     P=0.495N     P=0.496N    |P=0.532      (e)          P=0.236      P=0.494      |
|POLY 1.5           |     P=0.702N     P=0.232N     P=0.494N     P=0.501N    |P=0.539      (e)          P=0.237      P=0.497      |
|POLY 6             |     P=0.695N     P=0.235N     P=0.503N     P=0.498N    |P=0.526      (e)          P=0.235      P=0.492      |
|LOGISTIC REGRESSION|     P=0.695N     (e)          P=0.514N     P=0.565N    |P=0.535      (e)          P=0.234      P=0.492      |
|COCH-ARM / FISHERS |     P=0.702N     P=0.247N     P=0.500N     P=0.508N    |P=0.557      (e)          P=0.253      P=0.505      |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Islets, Pancreatic                                                                                                               |
|     Carcinoma or Adenoma                                                                                                        |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     3/50 (6%)    2/50 (4%)    6/50 (12%)   2/49 (4%)   |1/49 (2%)    2/50 (4%)    2/50 (4%)    1/50 (2%)    |
|POLY-3 ADJUSTED (b)|     8.2%         5.3%         15.9%        5.3%        |2.4%         4.6%         4.8%         2.5%         |
|TERMINAL (d)       |     3/18 (17%)   1/16 (6%)    3/15 (20%)   1/15 (7%)   |1/29 (3%)    2/30 (7%)    1/28 (4%)    0/27 (0%)    |
|FIRST INCIDENCE    |     733 (T)      592          566          621         |734 (T)      734 (T)      727          714          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.379N     P=0.539N     P=0.181      P=0.562N    |P=0.543N     P=0.512      P=0.480      P=0.738      |
|POLY 3             |     P=0.343N     P=0.485N     P=0.252      P=0.490N    |P=0.524N     P=0.517      P=0.499      P=0.755      |
|POLY 1.5           |     P=0.354N     P=0.488N     P=0.253      P=0.499N    |P=0.518N     P=0.513      P=0.500      P=0.757      |
|POLY 6             |     P=0.336N     P=0.489N     P=0.244      P=0.489N    |P=0.529N     P=0.519      P=0.498      P=0.752      |
|LOGISTIC REGRESSION|     P=0.345N     P=0.503N     P=0.223      P=0.507N    |P=0.540N     P=0.512      P=0.494      P=0.751      |
|COCH-ARM / FISHERS |     P=0.360N     P=0.500N     P=0.243      P=0.510N    |P=0.503N     P=0.508      P=0.508      P=0.747N     |
|=================================================================================================================================|
       Date:  10/01/97                           EXPERIMENT: 05135 TEST: 07                                            Page 6
                     Statistical Analysis of Primary Tumors in Rats(FISCHER344)       -                      ISOPRENE
                                         Terminal Sacrifice at 104 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Kidney: Renal Tubule                                                                                                             |
|     Adenoma                                                                                                                     |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     0/50 (0%)    2/50 (4%)    2/50 (4%)    6/50 (12%)  |0/50 (0%)    0/49 (0%)    1/50 (2%)    0/50 (0%)    |
|POLY-3 ADJUSTED (b)|     0.0%         5.3%         5.3%         15.8%       |0.0%         0.0%         2.4%         0.0%         |
|TERMINAL (d)       |     0/18 (0%)    0/16 (0%)    0/15 (0%)    1/15 (7%)   |0/29 (0%)    0/30 (0%)    1/28 (4%)    0/27 (0%)    |
|FIRST INCIDENCE    |     ---          559          566          630         |---          ---          734 (T)      ---          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.012 *    P=0.223      P=0.235      P=0.015 *   |P=0.754N     (e)          P=0.493      (e)          |
|POLY 3             |     P=0.009 **   P=0.244      P=0.242      P=0.016 *   |P=0.749N     (e)          P=0.496      (e)          |
|POLY 1.5           |     P=0.009 **   P=0.243      P=0.242      P=0.015 *   |P=0.746N     (e)          P=0.496      (e)          |
|POLY 6             |     P=0.009 **   P=0.242      P=0.238      P=0.016 *   |P=0.751N     (e)          P=0.496      (e)          |
|LOGISTIC REGRESSION|     P=0.010 *    P=0.234      P=0.231      P=0.017 *   |(e)          (e)          P=0.493      (e)          |
|COCH-ARM / FISHERS |     P=0.010 *    P=0.247      P=0.247      P=0.013 *   |P=0.739N     (e)          P=0.500      (e)          |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Kidney: Renal Tubule                                                                                                             |
|     Carcinoma or Adenoma                                                                                                        |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     0/50 (0%)    2/50 (4%)    2/50 (4%)    6/50 (12%)  |0/50 (0%)    0/49 (0%)    1/50 (2%)    0/50 (0%)    |
|POLY-3 ADJUSTED (b)|     0.0%         5.3%         5.3%         15.8%       |0.0%         0.0%         2.4%         0.0%         |
|TERMINAL (d)       |     0/18 (0%)    0/16 (0%)    0/15 (0%)    1/15 (7%)   |0/29 (0%)    0/30 (0%)    1/28 (4%)    0/27 (0%)    |
|FIRST INCIDENCE    |     ---          559          566          630         |---          ---          734 (T)      ---          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.012 *    P=0.223      P=0.235      P=0.015 *   |P=0.754N     (e)          P=0.493      (e)          |
|POLY 3             |     P=0.009 **   P=0.244      P=0.242      P=0.016 *   |P=0.749N     (e)          P=0.496      (e)          |
|POLY 1.5           |     P=0.009 **   P=0.243      P=0.242      P=0.015 *   |P=0.746N     (e)          P=0.496      (e)          |
|POLY 6             |     P=0.009 **   P=0.242      P=0.238      P=0.016 *   |P=0.751N     (e)          P=0.496      (e)          |
|LOGISTIC REGRESSION|     P=0.010 *    P=0.234      P=0.231      P=0.017 *   |(e)          (e)          P=0.493      (e)          |
|COCH-ARM / FISHERS |     P=0.010 *    P=0.247      P=0.247      P=0.013 *   |P=0.739N     (e)          P=0.500      (e)          |
|=================================================================================================================================|
       Date:  10/01/97                           EXPERIMENT: 05135 TEST: 07                                            Page 7
                     Statistical Analysis of Primary Tumors in Rats(FISCHER344)       -                      ISOPRENE
                                         Terminal Sacrifice at 104 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Liver                                                                                                                            |
|     Hepatocellular Adenoma                                                                                                      |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     0/50 (0%)    2/50 (4%)    0/50 (0%)    0/50 (0%)   |0/50 (0%)    0/50 (0%)    1/50 (2%)    0/50 (0%)    |
|POLY-3 ADJUSTED (b)|     0.0%         5.3%         0.0%         0.0%        |0.0%         0.0%         2.4%         0.0%         |
|TERMINAL (d)       |     0/18 (0%)    1/16 (6%)    0/15 (0%)    0/15 (0%)   |0/29 (0%)    0/30 (0%)    1/28 (4%)    0/27 (0%)    |
|FIRST INCIDENCE    |     ---          592          ---          ---         |---          ---          734 (T)      ---          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.473N     P=0.232      (e)          (e)         |P=0.754N     (e)          P=0.493      (e)          |
|POLY 3             |     P=0.456N     P=0.244      (e)          (e)         |P=0.750N     (e)          P=0.496      (e)          |
|POLY 1.5           |     P=0.461N     P=0.243      (e)          (e)         |P=0.747N     (e)          P=0.496      (e)          |
|POLY 6             |     P=0.454N     P=0.241      (e)          (e)         |P=0.752N     (e)          P=0.496      (e)          |
|LOGISTIC REGRESSION|     P=0.465N     P=0.240      (e)          (e)         |(e)          (e)          P=0.493      (e)          |
|COCH-ARM / FISHERS |     P=0.464N     P=0.247      (e)          (e)         |P=0.740N     (e)          P=0.500      (e)          |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Liver                                                                                                                            |
|     Hepatocellular Carcinoma or Hepatocellular Adenoma                                                                          |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     0/50 (0%)    3/50 (6%)    0/50 (0%)    0/50 (0%)   |0/50 (0%)    0/50 (0%)    1/50 (2%)    1/50 (2%)    |
|POLY-3 ADJUSTED (b)|     0.0%         7.9%         0.0%         0.0%        |0.0%         0.0%         2.4%         2.5%         |
|TERMINAL (d)       |     0/18 (0%)    1/16 (6%)    0/15 (0%)    0/15 (0%)   |0/29 (0%)    0/30 (0%)    1/28 (4%)    1/27 (4%)    |
|FIRST INCIDENCE    |     ---          592          ---          ---         |---          ---          734 (T)      734 (T)      |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.343N     P=0.112      (e)          (e)         |P=0.424      (e)          P=0.493      P=0.486      |
|POLY 3             |     P=0.324N     P=0.124      (e)          (e)         |P=0.424      (e)          P=0.496      P=0.491      |
|POLY 1.5           |     P=0.329N     P=0.123      (e)          (e)         |P=0.429      (e)          P=0.496      P=0.493      |
|POLY 6             |     P=0.321N     P=0.122      (e)          (e)         |P=0.419      (e)          P=0.496      P=0.489      |
|LOGISTIC REGRESSION|     P=0.335N     P=0.123      (e)          (e)         |(e)          (e)          P=0.493      P=0.486      |
|COCH-ARM / FISHERS |     P=0.335N     P=0.121      (e)          (e)         |P=0.443      (e)          P=0.500      P=0.500      |
|=================================================================================================================================|
       Date:  10/01/97                           EXPERIMENT: 05135 TEST: 07                                            Page 8
                     Statistical Analysis of Primary Tumors in Rats(FISCHER344)       -                      ISOPRENE
                                         Terminal Sacrifice at 104 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Liver                                                                                                                            |
|     Hepatocellular Carcinoma, Hepatocellular Adenoma,                                                                           |
|     or Hepatoblastoma                                                                                                           |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     0/50 (0%)    3/50 (6%)    0/50 (0%)    0/50 (0%)   |0/50 (0%)    0/50 (0%)    1/50 (2%)    1/50 (2%)    |
|POLY-3 ADJUSTED (b)|     0.0%         7.9%         0.0%         0.0%        |0.0%         0.0%         2.4%         2.5%         |
|TERMINAL (d)       |     0/18 (0%)    1/16 (6%)    0/15 (0%)    0/15 (0%)   |0/29 (0%)    0/30 (0%)    1/28 (4%)    1/27 (4%)    |
|FIRST INCIDENCE    |     ---          592          ---          ---         |---          ---          734 (T)      734 (T)      |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.343N     P=0.112      (e)          (e)         |P=0.424      (e)          P=0.493      P=0.486      |
|POLY 3             |     P=0.324N     P=0.124      (e)          (e)         |P=0.424      (e)          P=0.496      P=0.491      |
|POLY 1.5           |     P=0.329N     P=0.123      (e)          (e)         |P=0.429      (e)          P=0.496      P=0.493      |
|POLY 6             |     P=0.321N     P=0.122      (e)          (e)         |P=0.419      (e)          P=0.496      P=0.489      |
|LOGISTIC REGRESSION|     P=0.335N     P=0.123      (e)          (e)         |(e)          (e)          P=0.493      P=0.486      |
|COCH-ARM / FISHERS |     P=0.335N     P=0.121      (e)          (e)         |P=0.443      (e)          P=0.500      P=0.500      |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Lung                                                                                                                             |
|     Alveolar/Bronchiolar Adenoma                                                                                                |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     0/49 (0%)    0/50 (0%)    0/50 (0%)    0/50 (0%)   |1/50 (2%)    0/50 (0%)    0/50 (0%)    2/50 (4%)    |
|POLY-3 ADJUSTED (b)|     0.0%         0.0%         0.0%         0.0%        |2.4%         0.0%         0.0%         4.9%         |
|TERMINAL (d)       |     0/18 (0%)    0/16 (0%)    0/15 (0%)    0/15 (0%)   |1/29 (3%)    0/30 (0%)    0/28 (0%)    1/27 (4%)    |
|FIRST INCIDENCE    |     ---          ---          ---          ---         |734 (T)      ---          ---          625          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     (e)          (e)          (e)          (e)         |P=0.150      P=0.493N     P=0.507N     P=0.478      |
|POLY 3             |     (e)          (e)          (e)          (e)         |P=0.154      P=0.493N     P=0.504N     P=0.487      |
|POLY 1.5           |     (e)          (e)          (e)          (e)         |P=0.156      P=0.496N     P=0.504N     P=0.489      |
|POLY 6             |     (e)          (e)          (e)          (e)         |P=0.152      P=0.492N     P=0.504N     P=0.486      |
|LOGISTIC REGRESSION|     (e)          (e)          (e)          (e)         |P=0.155      (e)          (e)          P=0.488      |
|COCH-ARM / FISHERS |     (e)          (e)          (e)          (e)         |P=0.163      P=0.500N     P=0.500N     P=0.500      |
|=================================================================================================================================|
       Date:  10/01/97                           EXPERIMENT: 05135 TEST: 07                                            Page 9
                     Statistical Analysis of Primary Tumors in Rats(FISCHER344)       -                      ISOPRENE
                                         Terminal Sacrifice at 104 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Lung                                                                                                                             |
|     Alveolar/Bronchiolar Carcinoma                                                                                              |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     1/49 (2%)    0/50 (0%)    0/50 (0%)    3/50 (6%)   |0/50 (0%)    0/50 (0%)    0/50 (0%)    0/50 (0%)    |
|POLY-3 ADJUSTED (b)|     2.7%         0.0%         0.0%         7.9%        |0.0%         0.0%         0.0%         0.0%         |
|TERMINAL (d)       |     1/18 (6%)    0/16 (0%)    0/15 (0%)    0/15 (0%)   |0/29 (0%)    0/30 (0%)    0/28 (0%)    0/27 (0%)    |
|FIRST INCIDENCE    |     733 (T)      ---          ---          630         |---          ---          ---          ---          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.040 *    P=0.523N     P=0.536N     P=0.283     |(e)          (e)          (e)          (e)          |
|POLY 3             |     P=0.043 *    P=0.495N     P=0.498N     P=0.317     |(e)          (e)          (e)          (e)          |
|POLY 1.5           |     P=0.041 *    P=0.494N     P=0.495N     P=0.313     |(e)          (e)          (e)          (e)          |
|POLY 6             |     P=0.044 *    P=0.500N     P=0.504N     P=0.316     |(e)          (e)          (e)          (e)          |
|LOGISTIC REGRESSION|     P=0.043 *    (e)          (e)          P=0.309     |(e)          (e)          (e)          (e)          |
|COCH-ARM / FISHERS |     P=0.043 *    P=0.495N     P=0.495N     P=0.316     |(e)          (e)          (e)          (e)          |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Lung                                                                                                                             |
|     Alveolar/Bronchiolar Carcinoma or Alveolar/Bronchiolar                                                                      |
|     Adenoma                                                                                                                     |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     1/49 (2%)    0/50 (0%)    0/50 (0%)    3/50 (6%)   |1/50 (2%)    0/50 (0%)    0/50 (0%)    2/50 (4%)    |
|POLY-3 ADJUSTED (b)|     2.7%         0.0%         0.0%         7.9%        |2.4%         0.0%         0.0%         4.9%         |
|TERMINAL (d)       |     1/18 (6%)    0/16 (0%)    0/15 (0%)    0/15 (0%)   |1/29 (3%)    0/30 (0%)    0/28 (0%)    1/27 (4%)    |
|FIRST INCIDENCE    |     733 (T)      ---          ---          630         |734 (T)      ---          ---          625          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.040 *    P=0.523N     P=0.536N     P=0.283     |P=0.150      P=0.493N     P=0.507N     P=0.478      |
|POLY 3             |     P=0.043 *    P=0.495N     P=0.498N     P=0.317     |P=0.154      P=0.493N     P=0.504N     P=0.487      |
|POLY 1.5           |     P=0.041 *    P=0.494N     P=0.495N     P=0.313     |P=0.156      P=0.496N     P=0.504N     P=0.489      |
|POLY 6             |     P=0.044 *    P=0.500N     P=0.504N     P=0.316     |P=0.152      P=0.492N     P=0.504N     P=0.486      |
|LOGISTIC REGRESSION|     P=0.043 *    (e)          (e)          P=0.309     |P=0.155      (e)          (e)          P=0.488      |
|COCH-ARM / FISHERS |     P=0.043 *    P=0.495N     P=0.495N     P=0.316     |P=0.163      P=0.500N     P=0.500N     P=0.500      |
|=================================================================================================================================|
       Date:  10/01/97                           EXPERIMENT: 05135 TEST: 07                                            Page 10
                     Statistical Analysis of Primary Tumors in Rats(FISCHER344)       -                      ISOPRENE
                                         Terminal Sacrifice at 104 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Mammary Gland                                                                                                                    |
|     Carcinoma                                                                                                                   |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     0/50 (0%)    1/50 (2%)    1/50 (2%)    2/50 (4%)   |4/50 (8%)    2/50 (4%)    1/50 (2%)    3/50 (6%)    |
|POLY-3 ADJUSTED (b)|     0.0%         2.7%         2.7%         5.4%        |9.4%         4.6%         2.4%         7.3%         |
|TERMINAL (d)       |     0/18 (0%)    0/16 (0%)    1/15 (7%)    1/15 (7%)   |4/29 (14%)   1/30 (3%)    1/28 (4%)    2/27 (7%)    |
|FIRST INCIDENCE    |     ---          717          733 (T)      721         |734 (T)      714          734 (T)      432          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.239      P=0.462      P=0.464      P=0.205     |P=0.496      P=0.324N     P=0.187N     P=0.535N     |
|POLY 3             |     P=0.254      P=0.504      P=0.501      P=0.240     |P=0.517      P=0.321N     P=0.184N     P=0.515N     |
|POLY 1.5           |     P=0.252      P=0.504      P=0.503      P=0.238     |P=0.522      P=0.327N     P=0.184N     P=0.512N     |
|POLY 6             |     P=0.254      P=0.501      P=0.495      P=0.237     |P=0.513      P=0.315N     P=0.183N     P=0.516N     |
|LOGISTIC REGRESSION|     P=0.243      P=0.491      P=0.464      P=0.214     |P=0.514      P=0.323N     P=0.187N     P=0.513N     |
|COCH-ARM / FISHERS |     P=0.252      P=0.500      P=0.500      P=0.247     |P=0.536      P=0.339N     P=0.181N     P=0.500N     |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Mammary Gland                                                                                                                    |
|     Fibroadenoma                                                                                                                |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     2/50 (4%)    4/50 (8%)    6/50 (12%)   21/50 (42%) |19/50 (38%)  35/50 (70%)  32/50 (64%)  32/50 (64%)  |
|POLY-3 ADJUSTED (b)|     5.4%         10.5%        15.8%        54.2%       |42.9%        74.3%        73.7%        73.2%        |
|TERMINAL (d)       |     1/18 (6%)    2/16 (13%)   1/15 (7%)    10/15 (67%) |12/29 (41%)  23/30 (77%)  22/28 (79%)  20/27 (74%)  |
|FIRST INCIDENCE    |     724          629          591          664         |596          482          539          432          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P<0.001 **   P=0.303      P=0.117      P<0.001 **  |P=0.113      P=0.008 **   P=0.011 *    P=0.008 **   |
|POLY 3             |     P<0.001 **   P=0.353      P=0.140      P<0.001 **  |P=0.105      P<0.001 **   P=0.002 **   P=0.002 **   |
|POLY 1.5           |     P<0.001 **   P=0.350      P=0.140      P<0.001 **  |P=0.123      P<0.001 **   P=0.003 **   P=0.003 **   |
|POLY 6             |     P<0.001 **   P=0.351      P=0.137      P<0.001 **  |P=0.097      P<0.001 **   P<0.001 **   P=0.002 **   |
|LOGISTIC REGRESSION|     P<0.001 **   P=0.338      P=0.129      P<0.001 **  |P=0.089      P=0.002 **   P=0.003 **   P=0.003 **   |
|COCH-ARM / FISHERS |     P<0.001 **   P=0.339      P=0.134      P<0.001 **  |P=0.196      P<0.001 **   P=0.008 **   P=0.008 **   |
|=================================================================================================================================|
       Date:  10/01/97                           EXPERIMENT: 05135 TEST: 07                                            Page 11
                     Statistical Analysis of Primary Tumors in Rats(FISCHER344)       -                      ISOPRENE
                                         Terminal Sacrifice at 104 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Mammary Gland                                                                                                                    |
|     Fibroma, Fibroadenoma, Carcinoma, or Adenoma                                                                                |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     2/50 (4%)    5/50 (10%)   7/50 (14%)   21/50 (42%) |20/50 (40%)  35/50 (70%)  32/50 (64%)  32/50 (64%)  |
|POLY-3 ADJUSTED (b)|     5.4%         13.1%        18.4%        54.2%       |45.2%        74.3%        73.7%        73.2%        |
|TERMINAL (d)       |     1/18 (6%)    2/16 (13%)   2/15 (13%)   10/15 (67%) |13/29 (45%)  23/30 (77%)  22/28 (79%)  20/27 (74%)  |
|FIRST INCIDENCE    |     724          629          591          664         |596          482          539          432          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P<0.001 **   P=0.185      P=0.067      P<0.001 **  |P=0.129      P=0.012 *    P=0.016 *    P=0.013 *    |
|POLY 3             |     P<0.001 **   P=0.229      P=0.083      P<0.001 **  |P=0.127      P=0.003 **   P=0.004 **   P=0.004 **   |
|POLY 1.5           |     P<0.001 **   P=0.227      P=0.084      P<0.001 **  |P=0.147      P=0.002 **   P=0.005 **   P=0.006 **   |
|POLY 6             |     P<0.001 **   P=0.227      P=0.080      P<0.001 **  |P=0.118      P=0.003 **   P=0.002 **   P=0.004 **   |
|LOGISTIC REGRESSION|     P<0.001 **   P=0.214      P=0.075      P<0.001 **  |P=0.105      P=0.003 **   P=0.006 **   P=0.005 **   |
|COCH-ARM / FISHERS |     P<0.001 **   P=0.218      P=0.080      P<0.001 **  |P=0.224      P=0.002 **   P=0.014 *    P=0.014 *    |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Ovary                                                                                                                            |
|     Granulosa Cell Tumor: Benign, Malignant, NOS                                                                                |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |                                                        |2/50 (4%)    0/50 (0%)    0/50 (0%)    1/50 (2%)    |
|POLY-3 ADJUSTED (b)|                                                        |4.6%         0.0%         0.0%         2.5%         |
|TERMINAL (d)       |                                                        |1/29 (3%)    0/30 (0%)    0/28 (0%)    1/27 (4%)    |
|FIRST INCIDENCE    |                                                        |552          ---          ---          734 (T)      |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |                                                        |P=0.643      P=0.231N     P=0.249N     P=0.524N     |
|POLY 3             |                                                        |P=0.646      P=0.233N     P=0.244N     P=0.521N     |
|POLY 1.5           |                                                        |P=0.651      P=0.234N     P=0.243N     P=0.515N     |
|POLY 6             |                                                        |P=0.643      P=0.232N     P=0.246N     P=0.527N     |
|LOGISTIC REGRESSION|                                                        |P=0.667      P=0.253N     P=0.222N     P=0.498N     |
|COCH-ARM / FISHERS |                                                        |P=0.662      P=0.247N     P=0.247N     P=0.500N     |
|=================================================================================================================================|
       Date:  10/01/97                           EXPERIMENT: 05135 TEST: 07                                            Page 12
                     Statistical Analysis of Primary Tumors in Rats(FISCHER344)       -                      ISOPRENE
                                         Terminal Sacrifice at 104 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Pancreas                                                                                                                         |
|     Adenoma                                                                                                                     |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     3/50 (6%)    1/50 (2%)    3/50 (6%)    0/50 (0%)   |0/50 (0%)    0/50 (0%)    0/50 (0%)    0/50 (0%)    |
|POLY-3 ADJUSTED (b)|     8.1%         2.7%         8.0%         0.0%        |0.0%         0.0%         0.0%         0.0%         |
|TERMINAL (d)       |     1/18 (6%)    1/16 (6%)    1/15 (7%)    0/15 (0%)   |0/29 (0%)    0/30 (0%)    0/28 (0%)    0/27 (0%)    |
|FIRST INCIDENCE    |     600          733 (T)      667          ---         |---          ---          ---          ---          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.143N     P=0.340N     P=0.611      P=0.135N    |(e)          (e)          (e)          (e)          |
|POLY 3             |     P=0.132N     P=0.302N     P=0.663N     P=0.117N    |(e)          (e)          (e)          (e)          |
|POLY 1.5           |     P=0.135N     P=0.300N     P=0.658N     P=0.118N    |(e)          (e)          (e)          (e)          |
|POLY 6             |     P=0.130N     P=0.313N     P=0.653      P=0.120N    |(e)          (e)          (e)          (e)          |
|LOGISTIC REGRESSION|     P=0.131N     P=0.301N     P=0.663      P=0.119N    |(e)          (e)          (e)          (e)          |
|COCH-ARM / FISHERS |     P=0.134N     P=0.309N     P=0.661N     P=0.121N    |(e)          (e)          (e)          (e)          |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Pituitary Gland: Pars Distalis or Unspecified Site                                                                               |
|     Adenoma                                                                                                                     |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     39/50 (78%)  40/50 (80%)  39/50 (78%)  31/49 (63%) |33/50 (66%)  27/50 (54%)  36/50 (72%)  27/50 (54%)  |
|POLY-3 ADJUSTED (b)|     86.0%        84.4%        82.9%        73.5%       |72.2%        56.4%        78.6%        61.7%        |
|TERMINAL (d)       |     16/18 (89%)  12/16 (75%)  10/15 (67%)  13/15 (87%) |22/29 (76%)  14/30 (47%)  22/28 (79%)  18/27 (67%)  |
|FIRST INCIDENCE    |     342          420          454          560         |454          482          510          432          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.131N     P=0.386      P=0.386      P=0.260N    |P=0.357N     P=0.157N     P=0.302      P=0.302N     |
|POLY 3             |     P=0.066N     P=0.529N     P=0.444N     P=0.095N    |P=0.274N     P=0.078N     P=0.313      P=0.191N     |
|POLY 1.5           |     P=0.053N     P=0.585N     P=0.488N     P=0.095N    |P=0.228N     P=0.105N     P=0.298      P=0.184N     |
|POLY 6             |     P=0.095N     P=0.475N     P=0.413N     P=0.106N    |P=0.342N     P=0.054N     P=0.344      P=0.204N     |
|LOGISTIC REGRESSION|     P=0.025N*    P=0.552      P=0.555N     P=0.059N    |P=0.222N     P=0.134N     P=0.273      P=0.207N     |
|COCH-ARM / FISHERS |     P=0.024N*    P=0.500      P=0.595N     P=0.082N    |P=0.156N     P=0.154N     P=0.333      P=0.154N     |
|=================================================================================================================================|
       Date:  10/01/97                           EXPERIMENT: 05135 TEST: 07                                            Page 13
                     Statistical Analysis of Primary Tumors in Rats(FISCHER344)       -                      ISOPRENE
                                         Terminal Sacrifice at 104 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Pituitary Gland: Pars Distalis or Unspecified Site                                                                               |
|     Carcinoma or Adenoma                                                                                                        |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     39/50 (78%)  40/50 (80%)  39/50 (78%)  31/49 (63%) |34/50 (68%)  27/50 (54%)  37/50 (74%)  27/50 (54%)  |
|POLY-3 ADJUSTED (b)|     86.0%        84.4%        82.9%        73.5%       |73.5%        56.4%        80.8%        61.7%        |
|TERMINAL (d)       |     16/18 (89%)  12/16 (75%)  10/15 (67%)  13/15 (87%) |22/29 (76%)  14/30 (47%)  23/28 (82%)  18/27 (67%)  |
|FIRST INCIDENCE    |     342          420          454          560         |454          482          510          432          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.131N     P=0.386      P=0.386      P=0.260N    |P=0.312N     P=0.124N     P=0.301      P=0.249N     |
|POLY 3             |     P=0.066N     P=0.529N     P=0.444N     P=0.095N    |P=0.230N     P=0.059N     P=0.269      P=0.155N     |
|POLY 1.5           |     P=0.053N     P=0.585N     P=0.488N     P=0.095N    |P=0.184N     P=0.076N     P=0.272      P=0.141N     |
|POLY 6             |     P=0.095N     P=0.475N     P=0.413N     P=0.106N    |P=0.298N     P=0.043N*    P=0.278      P=0.177N     |
|LOGISTIC REGRESSION|     P=0.025N*    P=0.552      P=0.555N     P=0.059N    |P=0.173N     P=0.099N     P=0.270      P=0.149N     |
|COCH-ARM / FISHERS |     P=0.024N*    P=0.500      P=0.595N     P=0.082N    |P=0.119N     P=0.109N     P=0.330      P=0.109N     |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Skin                                                                                                                             |
|     Basal Cell Adenoma, Basosquamous Tumor Benign, or                                                                           |
|     Trichoepithelioma                                                                                                           |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     1/50 (2%)    1/50 (2%)    2/50 (4%)    1/50 (2%)   |0/50 (0%)    0/50 (0%)    0/50 (0%)    0/50 (0%)    |
|POLY-3 ADJUSTED (b)|     2.7%         2.7%         5.4%         2.7%        |0.0%         0.0%         0.0%         0.0%         |
|TERMINAL (d)       |     1/18 (6%)    1/16 (6%)    0/15 (0%)    0/15 (0%)   |0/29 (0%)    0/30 (0%)    0/28 (0%)    0/27 (0%)    |
|FIRST INCIDENCE    |     733 (T)      733 (T)      684          622         |---          ---          ---          ---          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.630N     P=0.737      P=0.457      P=0.744     |(e)          (e)          (e)          (e)          |
|POLY 3             |     P=0.609N     P=0.757N     P=0.504      P=0.756N    |(e)          (e)          (e)          (e)          |
|POLY 1.5           |     P=0.614N     P=0.756N     P=0.506      P=0.759N    |(e)          (e)          (e)          (e)          |
|POLY 6             |     P=0.605N     P=0.762N     P=0.496      P=0.757N    |(e)          (e)          (e)          (e)          |
|LOGISTIC REGRESSION|     P=0.612N     P=0.737      P=0.477      P=0.761N    |(e)          (e)          (e)          (e)          |
|COCH-ARM / FISHERS |     P=0.615N     P=0.753N     P=0.500      P=0.753N    |(e)          (e)          (e)          (e)          |
|=================================================================================================================================|
       Date:  10/01/97                           EXPERIMENT: 05135 TEST: 07                                            Page 14
                     Statistical Analysis of Primary Tumors in Rats(FISCHER344)       -                      ISOPRENE
                                         Terminal Sacrifice at 104 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Skin                                                                                                                             |
|     Basal Cell Carcinoma, Basal Cell Adenoma, Basosquamous                                                                      |
|     Tumor (benign, malignant or NOS), or Trichoepithelioma                                                                      |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     1/50 (2%)    1/50 (2%)    2/50 (4%)    1/50 (2%)   |0/50 (0%)    0/50 (0%)    0/50 (0%)    0/50 (0%)    |
|POLY-3 ADJUSTED (b)|     2.7%         2.7%         5.4%         2.7%        |0.0%         0.0%         0.0%         0.0%         |
|TERMINAL (d)       |     1/18 (6%)    1/16 (6%)    0/15 (0%)    0/15 (0%)   |0/29 (0%)    0/30 (0%)    0/28 (0%)    0/27 (0%)    |
|FIRST INCIDENCE    |     733 (T)      733 (T)      684          622         |---          ---          ---          ---          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.630N     P=0.737      P=0.457      P=0.744     |(e)          (e)          (e)          (e)          |
|POLY 3             |     P=0.609N     P=0.757N     P=0.504      P=0.756N    |(e)          (e)          (e)          (e)          |
|POLY 1.5           |     P=0.614N     P=0.756N     P=0.506      P=0.759N    |(e)          (e)          (e)          (e)          |
|POLY 6             |     P=0.605N     P=0.762N     P=0.496      P=0.757N    |(e)          (e)          (e)          (e)          |
|LOGISTIC REGRESSION|     P=0.612N     P=0.737      P=0.477      P=0.761N    |(e)          (e)          (e)          (e)          |
|COCH-ARM / FISHERS |     P=0.615N     P=0.753N     P=0.500      P=0.753N    |(e)          (e)          (e)          (e)          |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Skin                                                                                                                             |
|     Basal or Sq. Cell Carcinoma, Carcinoma, Basosq. Tumor                                                                       |
|     (M or B), Basal Cell Adenoma, Adenoma, Papilloma, Sq Papilloma, Keratoacanthoma, Trichoepitheliom                           |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     3/50 (6%)    3/50 (6%)    4/50 (8%)    4/50 (8%)   |2/50 (4%)    2/50 (4%)    0/50 (0%)    0/50 (0%)    |
|POLY-3 ADJUSTED (b)|     8.0%         8.0%         10.8%        10.5%       |4.7%         4.5%         0.0%         0.0%         |
|TERMINAL (d)       |     2/18 (11%)   3/16 (19%)   2/15 (13%)   1/15 (7%)   |2/29 (7%)    1/30 (3%)    0/28 (0%)    0/27 (0%)    |
|FIRST INCIDENCE    |     454          733 (T)      684          622         |734 (T)      670          ---          ---          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.434      P=0.621      P=0.434      P=0.448     |P=0.245N     P=0.678N     P=0.246N     P=0.254N     |
|POLY 3             |     P=0.487      P=0.664      P=0.495      P=0.507     |P=0.234N     P=0.681N     P=0.241N     P=0.247N     |
|POLY 1.5           |     P=0.476      P=0.659N     P=0.503      P=0.501     |P=0.231N     P=0.686N     P=0.241N     P=0.245N     |
|POLY 6             |     P=0.500      P=0.652      P=0.477      P=0.508     |P=0.236N     P=0.676N     P=0.241N     P=0.249N     |
|LOGISTIC REGRESSION|     P=0.483      P=0.657N     P=0.500      P=0.502     |P=0.239N     P=0.682N     (e)          (e)          |
|COCH-ARM / FISHERS |     P=0.478      P=0.661N     P=0.500      P=0.500     |P=0.226N     P=0.691N     P=0.247N     P=0.247N     |
|=================================================================================================================================|
       Date:  10/01/97                           EXPERIMENT: 05135 TEST: 07                                            Page 15
                     Statistical Analysis of Primary Tumors in Rats(FISCHER344)       -                      ISOPRENE
                                         Terminal Sacrifice at 104 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Skin                                                                                                                             |
|     Fibroma                                                                                                                     |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     0/50 (0%)    4/50 (8%)    1/50 (2%)    2/50 (4%)   |0/50 (0%)    0/50 (0%)    1/50 (2%)    0/50 (0%)    |
|POLY-3 ADJUSTED (b)|     0.0%         10.4%        2.7%         5.3%        |0.0%         0.0%         2.4%         0.0%         |
|TERMINAL (d)       |     0/18 (0%)    1/16 (6%)    0/15 (0%)    1/15 (7%)   |0/29 (0%)    0/30 (0%)    1/28 (4%)    0/27 (0%)    |
|FIRST INCIDENCE    |     ---          538          591          588         |---          ---          734 (T)      ---          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.570      P=0.061      P=0.495      P=0.228     |P=0.754N     (e)          P=0.493      (e)          |
|POLY 3             |     P=0.587      P=0.065      P=0.504      P=0.242     |P=0.750N     (e)          P=0.496      (e)          |
|POLY 1.5           |     P=0.579      P=0.064      P=0.504      P=0.239     |P=0.747N     (e)          P=0.496      (e)          |
|POLY 6             |     P=0.591      P=0.064      P=0.500      P=0.242     |P=0.752N     (e)          P=0.496      (e)          |
|LOGISTIC REGRESSION|     P=0.575      P=0.064      P=0.479      P=0.238     |(e)          (e)          P=0.493      (e)          |
|COCH-ARM / FISHERS |     P=0.575      P=0.059      P=0.500      P=0.247     |P=0.740N     (e)          P=0.500      (e)          |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Skin                                                                                                                             |
|     Fibroma, Fibrosarcoma, Sarcoma, Myxoma, Myxosarcoma,                                                                        |
|     or Fibrous Histiocytoma                                                                                                     |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     0/50 (0%)    4/50 (8%)    2/50 (4%)    2/50 (4%)   |2/50 (4%)    1/50 (2%)    1/50 (2%)    1/50 (2%)    |
|POLY-3 ADJUSTED (b)|     0.0%         10.4%        5.3%         5.3%        |4.6%         2.3%         2.4%         2.5%         |
|TERMINAL (d)       |     0/18 (0%)    1/16 (6%)    0/15 (0%)    1/15 (7%)   |1/29 (3%)    1/30 (3%)    1/28 (4%)    0/27 (0%)    |
|FIRST INCIDENCE    |     ---          538          580          588         |482          734 (T)      734 (T)      681          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.631      P=0.061      P=0.237      P=0.228     |P=0.599N     P=0.490N     P=0.508N     P=0.516N     |
|POLY 3             |     P=0.642      P=0.065      P=0.244      P=0.242     |P=0.590N     P=0.494N     P=0.513N     P=0.520N     |
|POLY 1.5           |     P=0.635      P=0.064      P=0.243      P=0.239     |P=0.584N     P=0.496N     P=0.510N     P=0.515N     |
|POLY 6             |     P=0.645      P=0.064      P=0.241      P=0.242     |P=0.593N     P=0.494N     P=0.515N     P=0.524N     |
|LOGISTIC REGRESSION|     P=0.634      P=0.064      P=0.207      P=0.238     |P=0.566N     P=0.523N     P=0.483N     P=0.465N     |
|COCH-ARM / FISHERS |     P=0.632      P=0.059      P=0.247      P=0.247     |P=0.572N     P=0.500N     P=0.500N     P=0.500N     |
|=================================================================================================================================|
       Date:  10/01/97                           EXPERIMENT: 05135 TEST: 07                                            Page 16
                     Statistical Analysis of Primary Tumors in Rats(FISCHER344)       -                      ISOPRENE
                                         Terminal Sacrifice at 104 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Skin                                                                                                                             |
|     Fibrosarcoma, Sarcoma, Myxosarcoma, or Fibrous Histiocytoma                                                                 |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     0/50 (0%)    0/50 (0%)    1/50 (2%)    0/50 (0%)   |2/50 (4%)    1/50 (2%)    0/50 (0%)    1/50 (2%)    |
|POLY-3 ADJUSTED (b)|     0.0%         0.0%         2.7%         0.0%        |4.6%         2.3%         0.0%         2.5%         |
|TERMINAL (d)       |     0/18 (0%)    0/16 (0%)    0/15 (0%)    0/15 (0%)   |1/29 (3%)    1/30 (3%)    0/28 (0%)    0/27 (0%)    |
|FIRST INCIDENCE    |     ---          ---          580          ---         |482          734 (T)      ---          681          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.722N     (e)          P=0.500      (e)         |P=0.687N     P=0.490N     P=0.244N     P=0.516N     |
|POLY 3             |     P=0.739N     (e)          P=0.504      (e)         |P=0.675N     P=0.494N     P=0.245N     P=0.520N     |
|POLY 1.5           |     P=0.741N     (e)          P=0.504      (e)         |P=0.672N     P=0.496N     P=0.243N     P=0.515N     |
|POLY 6             |     P=0.740N     (e)          P=0.500      (e)         |P=0.677N     P=0.494N     P=0.246N     P=0.524N     |
|LOGISTIC REGRESSION|     P=0.720N     (e)          P=0.472      (e)         |P=0.648N     P=0.523N     P=0.202N     P=0.465N     |
|COCH-ARM / FISHERS |     P=0.740N     (e)          P=0.500      (e)         |P=0.665N     P=0.500N     P=0.247N     P=0.500N     |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Skin                                                                                                                             |
|     Keratoacanthoma                                                                                                             |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     1/50 (2%)    2/50 (4%)    1/50 (2%)    2/50 (4%)   |0/50 (0%)    1/50 (2%)    0/50 (0%)    0/50 (0%)    |
|POLY-3 ADJUSTED (b)|     2.7%         5.3%         2.7%         5.4%        |0.0%         2.3%         0.0%         0.0%         |
|TERMINAL (d)       |     1/18 (6%)    2/16 (13%)   1/15 (7%)    1/15 (7%)   |0/29 (0%)    0/30 (0%)    0/28 (0%)    0/27 (0%)    |
|FIRST INCIDENCE    |     733 (T)      733 (T)      733 (T)      691         |---          670          ---          ---          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.455      P=0.458      P=0.722      P=0.448     |P=0.705N     P=0.516      (e)          (e)          |
|POLY 3             |     P=0.499      P=0.507      P=0.760N     P=0.506     |P=0.682N     P=0.508      (e)          (e)          |
|POLY 1.5           |     P=0.493      P=0.507      P=0.758N     P=0.503     |P=0.683N     P=0.505      (e)          (e)          |
|POLY 6             |     P=0.502      P=0.500      P=0.757      P=0.505     |P=0.682N     P=0.510      (e)          (e)          |
|LOGISTIC REGRESSION|     P=0.484      P=0.458      P=0.722      P=0.484     |P=0.680N     P=0.493      (e)          (e)          |
|COCH-ARM / FISHERS |     P=0.494      P=0.500      P=0.753N     P=0.500     |P=0.684N     P=0.500      (e)          (e)          |
|=================================================================================================================================|
       Date:  10/01/97                           EXPERIMENT: 05135 TEST: 07                                            Page 17
                     Statistical Analysis of Primary Tumors in Rats(FISCHER344)       -                      ISOPRENE
                                         Terminal Sacrifice at 104 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Skin                                                                                                                             |
|     Squamous Cell Papilloma                                                                                                     |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     0/50 (0%)    1/50 (2%)    0/50 (0%)    0/50 (0%)   |2/50 (4%)    1/50 (2%)    0/50 (0%)    0/50 (0%)    |
|POLY-3 ADJUSTED (b)|     0.0%         2.7%         0.0%         0.0%        |4.7%         2.3%         0.0%         0.0%         |
|TERMINAL (d)       |     0/18 (0%)    1/16 (6%)    0/15 (0%)    0/15 (0%)   |2/29 (7%)    1/30 (3%)    0/28 (0%)    0/27 (0%)    |
|FIRST INCIDENCE    |     ---          733 (T)      ---          ---         |734 (T)      734 (T)      ---          ---          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.702N     P=0.477      (e)          (e)         |P=0.320N     P=0.488N     P=0.246N     P=0.254N     |
|POLY 3             |     P=0.681N     P=0.504      (e)          (e)         |P=0.313N     P=0.489N     P=0.241N     P=0.247N     |
|POLY 1.5           |     P=0.683N     P=0.504      (e)          (e)         |P=0.310N     P=0.493N     P=0.241N     P=0.245N     |
|POLY 6             |     P=0.680N     P=0.500      (e)          (e)         |P=0.315N     P=0.485N     P=0.241N     P=0.249N     |
|LOGISTIC REGRESSION|     (e)          P=0.477      (e)          (e)         |P=0.320N     P=0.488N     (e)          (e)          |
|COCH-ARM / FISHERS |     P=0.684N     P=0.500      (e)          (e)         |P=0.304N     P=0.500N     P=0.247N     P=0.247N     |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Skin                                                                                                                             |
|     Squamous Cell Papilloma, Papilloma, Squamous Cell                                                                           |
|     Carcinoma or Keratoacanthoma                                                                                                |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     2/50 (4%)    3/50 (6%)    2/50 (4%)    3/50 (6%)   |2/50 (4%)    2/50 (4%)    0/50 (0%)    0/50 (0%)    |
|POLY-3 ADJUSTED (b)|     5.3%         8.0%         5.4%         8.0%        |4.7%         4.5%         0.0%         0.0%         |
|TERMINAL (d)       |     1/18 (6%)    3/16 (19%)   2/15 (13%)   1/15 (7%)   |2/29 (7%)    1/30 (3%)    0/28 (0%)    0/27 (0%)    |
|FIRST INCIDENCE    |     454          733 (T)      733 (T)      686         |734 (T)      670          ---          ---          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.450      P=0.458      P=0.652      P=0.453     |P=0.245N     P=0.678N     P=0.246N     P=0.254N     |
|POLY 3             |     P=0.499      P=0.500      P=0.690      P=0.501     |P=0.234N     P=0.681N     P=0.241N     P=0.247N     |
|POLY 1.5           |     P=0.492      P=0.504      P=0.694N     P=0.499     |P=0.231N     P=0.686N     P=0.241N     P=0.245N     |
|POLY 6             |     P=0.504      P=0.487      P=0.677      P=0.498     |P=0.236N     P=0.676N     P=0.241N     P=0.249N     |
|LOGISTIC REGRESSION|     P=0.499      P=0.508      P=0.692N     P=0.501     |P=0.239N     P=0.682N     (e)          (e)          |
|COCH-ARM / FISHERS |     P=0.495      P=0.500      P=0.691N     P=0.500     |P=0.226N     P=0.691N     P=0.247N     P=0.247N     |
|=================================================================================================================================|
       Date:  10/01/97                           EXPERIMENT: 05135 TEST: 07                                            Page 18
                     Statistical Analysis of Primary Tumors in Rats(FISCHER344)       -                      ISOPRENE
                                         Terminal Sacrifice at 104 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Skin                                                                                                                             |
|     Squamous Cell Papilloma, Papilloma, or Keratoacanthoma                                                                      |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     1/50 (2%)    3/50 (6%)    1/50 (2%)    2/50 (4%)   |2/50 (4%)    2/50 (4%)    0/50 (0%)    0/50 (0%)    |
|POLY-3 ADJUSTED (b)|     2.7%         8.0%         2.7%         5.4%        |4.7%         4.5%         0.0%         0.0%         |
|TERMINAL (d)       |     1/18 (6%)    3/16 (19%)   1/15 (7%)    1/15 (7%)   |2/29 (7%)    1/30 (3%)    0/28 (0%)    0/27 (0%)    |
|FIRST INCIDENCE    |     733 (T)      733 (T)      733 (T)      691         |734 (T)      670          ---          ---          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.547      P=0.258      P=0.722      P=0.448     |P=0.245N     P=0.678N     P=0.246N     P=0.254N     |
|POLY 3             |     P=0.593      P=0.311      P=0.760N     P=0.506     |P=0.234N     P=0.681N     P=0.241N     P=0.247N     |
|POLY 1.5           |     P=0.586      P=0.312      P=0.758N     P=0.503     |P=0.231N     P=0.686N     P=0.241N     P=0.245N     |
|POLY 6             |     P=0.597      P=0.303      P=0.757      P=0.505     |P=0.236N     P=0.676N     P=0.241N     P=0.249N     |
|LOGISTIC REGRESSION|     P=0.576      P=0.258      P=0.722      P=0.484     |P=0.239N     P=0.682N     (e)          (e)          |
|COCH-ARM / FISHERS |     P=0.586      P=0.309      P=0.753N     P=0.500     |P=0.226N     P=0.691N     P=0.247N     P=0.247N     |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Testes                                                                                                                           |
|     Adenoma                                                                                                                     |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     33/50 (66%)  37/50 (74%)  44/50 (88%)  48/50 (96%) |                                                    |
|POLY-3 ADJUSTED (b)|     78.4%        85.3%        94.4%        99.9%       |                                                    |
|TERMINAL (d)       |     16/18 (89%)  16/16 (100%) 15/15 (100%) 15/15 (100%)|                                                    |
|FIRST INCIDENCE    |     454          398          454          361         |                                                    |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.026 *    P=0.183      P=0.024 *    P=0.009 **  |                                                    |
|POLY 3             |     P<0.001 **   P=0.259      P=0.010 *    P<0.001 **  |                                                    |
|POLY 1.5           |     P<0.001 **   P=0.278      P=0.008 **   P<0.001 **  |                                                    |
|POLY 6             |     P=0.004 **   P=0.201      P=0.020 *    P<0.001 **  |                                                    |
|LOGISTIC REGRESSION|     P<0.001 **   P=0.327      P=0.008 **   P<0.001 **  |                                                    |
|COCH-ARM / FISHERS |     P<0.001 **   P=0.257      P=0.008 **   P<0.001 **  |                                                    |
|=================================================================================================================================|
       Date:  10/01/97                           EXPERIMENT: 05135 TEST: 07                                            Page 19
                     Statistical Analysis of Primary Tumors in Rats(FISCHER344)       -                      ISOPRENE
                                         Terminal Sacrifice at 104 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Thyroid Gland: C-Cell                                                                                                            |
|     Adenoma                                                                                                                     |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     3/49 (6%)    4/50 (8%)    3/49 (6%)    3/50 (6%)   |6/48 (13%)   4/50 (8%)    2/49 (4%)    2/50 (4%)    |
|POLY-3 ADJUSTED (b)|     8.1%         10.6%        8.2%         8.0%        |14.4%        9.1%         4.9%         4.9%         |
|TERMINAL (d)       |     1/18 (6%)    2/16 (13%)   2/15 (13%)   2/15 (13%)  |5/29 (17%)   3/30 (10%)   2/28 (7%)    1/27 (4%)    |
|FIRST INCIDENCE    |     482          702          469          581         |580          695          734 (T)      653          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.583N     P=0.455      P=0.629      P=0.636     |P=0.247N     P=0.349N     P=0.145N     P=0.158N     |
|POLY 3             |     P=0.546N     P=0.506      P=0.659      P=0.657N    |P=0.226N     P=0.334N     P=0.138N     P=0.137N     |
|POLY 1.5           |     P=0.552N     P=0.514      P=0.661N     P=0.657N    |P=0.220N     P=0.337N     P=0.135N     P=0.133N     |
|POLY 6             |     P=0.545N     P=0.488      P=0.639      P=0.664     |P=0.230N     P=0.336N     P=0.142N     P=0.143N     |
|LOGISTIC REGRESSION|     P=0.548N     P=0.519      P=0.645      P=0.654N    |P=0.233N     P=0.329N     P=0.137N     P=0.136N     |
|COCH-ARM / FISHERS |     P=0.546N     P=0.511      P=0.661N     P=0.651N    |P=0.206N     P=0.344N     P=0.127N     P=0.121N     |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Thyroid Gland: C-Cell                                                                                                            |
|     Carcinoma                                                                                                                   |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     1/49 (2%)    1/50 (2%)    1/49 (2%)    3/50 (6%)   |2/48 (4%)    4/50 (8%)    2/49 (4%)    0/50 (0%)    |
|POLY-3 ADJUSTED (b)|     2.8%         2.7%         2.8%         8.0%        |4.9%         9.0%         4.9%         0.0%         |
|TERMINAL (d)       |     1/18 (6%)    0/16 (0%)    0/15 (0%)    2/15 (13%)  |2/29 (7%)    3/30 (10%)   2/28 (7%)    0/27 (0%)    |
|FIRST INCIDENCE    |     733 (T)      657          692          611         |734 (T)      626          734 (T)      ---          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.152      P=0.751      P=0.726      P=0.268     |P=0.110N     P=0.354      P=0.684      P=0.254N     |
|POLY 3             |     P=0.171      P=0.750N     P=0.760N     P=0.321     |P=0.104N     P=0.371      P=0.691      P=0.240N     |
|POLY 1.5           |     P=0.167      P=0.751N     P=0.758N     P=0.317     |P=0.101N     P=0.366      P=0.693      P=0.237N     |
|POLY 6             |     P=0.172      P=0.753N     P=0.758      P=0.321     |P=0.107N     P=0.374      P=0.689      P=0.244N     |
|LOGISTIC REGRESSION|     P=0.170      P=0.756N     P=0.749      P=0.312     |P=0.106N     P=0.366      P=0.684      (e)          |
|COCH-ARM / FISHERS |     P=0.167      P=0.747N     P=0.753N     P=0.316     |P=0.095N     P=0.359      P=0.684N     P=0.237N     |
|=================================================================================================================================|
       Date:  10/01/97                           EXPERIMENT: 05135 TEST: 07                                            Page 20
                     Statistical Analysis of Primary Tumors in Rats(FISCHER344)       -                      ISOPRENE
                                         Terminal Sacrifice at 104 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Thyroid Gland: C-Cell                                                                                                            |
|     Carcinoma or Adenoma                                                                                                        |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     4/49 (8%)    5/50 (10%)   4/49 (8%)    6/50 (12%)  |8/48 (17%)   8/50 (16%)   4/49 (8%)    2/50 (4%)    |
|POLY-3 ADJUSTED (b)|     10.8%        13.2%        10.9%        15.7%       |19.2%        18.0%        9.8%         4.9%         |
|TERMINAL (d)       |     2/18 (11%)   2/16 (13%)   2/15 (13%)   4/15 (27%)  |7/29 (24%)   6/30 (20%)   4/28 (14%)   1/27 (4%)    |
|FIRST INCIDENCE    |     482          657          469          581         |580          626          734 (T)      653          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.305      P=0.454      P=0.592      P=0.324     |P=0.057N     P=0.579N     P=0.190N     P=0.060N     |
|POLY 3             |     P=0.348      P=0.512      P=0.641      P=0.383     |P=0.048N*    P=0.554N     P=0.184N     P=0.046N*    |
|POLY 1.5           |     P=0.341      P=0.518      P=0.641N     P=0.381     |P=0.046N*    P=0.560N     P=0.180N     P=0.044N*    |
|POLY 6             |     P=0.352      P=0.495      P=0.621      P=0.375     |P=0.050N     P=0.552N     P=0.190N     P=0.049N*    |
|LOGISTIC REGRESSION|     P=0.345      P=0.524      P=0.641      P=0.384     |P=0.051N     P=0.553N     P=0.183N     P=0.049N*    |
|COCH-ARM / FISHERS |     P=0.345      P=0.513      P=0.643N     P=0.383     |P=0.041N*    P=0.572N     P=0.168N     P=0.039N*    |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Thyroid Gland: Follicular Cell                                                                                                   |
|     Carcinoma or Adenoma                                                                                                        |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     2/49 (4%)    2/50 (4%)    2/49 (4%)    0/50 (0%)   |0/48 (0%)    0/50 (0%)    1/49 (2%)    1/50 (2%)    |
|POLY-3 ADJUSTED (b)|     5.6%         5.3%         5.6%         0.0%        |0.0%         0.0%         2.5%         2.5%         |
|TERMINAL (d)       |     1/18 (6%)    1/16 (6%)    2/15 (13%)   0/15 (0%)   |0/29 (0%)    0/30 (0%)    1/28 (4%)    1/27 (4%)    |
|FIRST INCIDENCE    |     704          717          733 (T)      ---         |---          ---          734 (T)      734 (T)      |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.178N     P=0.638      P=0.628      P=0.270N    |P=0.424      (e)          P=0.493      P=0.486      |
|POLY 3             |     P=0.158N     P=0.680N     P=0.695N     P=0.229N    |P=0.427      (e)          P=0.498      P=0.497      |
|POLY 1.5           |     P=0.162N     P=0.679N     P=0.690N     P=0.231N    |P=0.433      (e)          P=0.500      P=0.500      |
|POLY 6             |     P=0.155N     P=0.689N     P=0.683      P=0.231N    |P=0.421      (e)          P=0.497      P=0.493      |
|LOGISTIC REGRESSION|     P=0.162N     P=0.682      P=0.645      P=0.240N    |(e)          (e)          P=0.493      P=0.486      |
|COCH-ARM / FISHERS |     P=0.160N     P=0.684N     P=0.691N     P=0.242N    |P=0.448      (e)          P=0.505      P=0.510      |
|=================================================================================================================================|
       Date:  10/01/97                           EXPERIMENT: 05135 TEST: 07                                            Page 21
                     Statistical Analysis of Primary Tumors in Rats(FISCHER344)       -                      ISOPRENE
                                         Terminal Sacrifice at 104 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Uterus                                                                                                                           |
|     Polyp Stromal                                                                                                               |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |                                                        |8/50 (16%)   5/50 (10%)   6/50 (12%)   8/50 (16%)   |
|POLY-3 ADJUSTED (b)|                                                        |18.4%        11.3%        14.4%        19.1%        |
|TERMINAL (d)       |                                                        |4/29 (14%)   3/30 (10%)   5/28 (18%)   3/27 (11%)   |
|FIRST INCIDENCE    |                                                        |539          686          699          625          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |                                                        |P=0.306      P=0.264N     P=0.407N     P=0.542      |
|POLY 3             |                                                        |P=0.338      P=0.262N     P=0.415N     P=0.580      |
|POLY 1.5           |                                                        |P=0.343      P=0.267N     P=0.408N     P=0.583      |
|POLY 6             |                                                        |P=0.341      P=0.259N     P=0.424N     P=0.583      |
|LOGISTIC REGRESSION|                                                        |P=0.327      P=0.260N     P=0.401N     P=0.586      |
|COCH-ARM / FISHERS |                                                        |P=0.369      P=0.277N     P=0.387N     P=0.607N     |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Uterus                                                                                                                           |
|     Sarcoma Stromal or Polyp Stromal                                                                                            |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |                                                        |8/50 (16%)   6/50 (12%)   6/50 (12%)   8/50 (16%)   |
|POLY-3 ADJUSTED (b)|                                                        |18.4%        13.4%        14.4%        19.1%        |
|TERMINAL (d)       |                                                        |4/29 (14%)   3/30 (10%)   5/28 (18%)   3/27 (11%)   |
|FIRST INCIDENCE    |                                                        |539          587          699          625          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |                                                        |P=0.352      P=0.364N     P=0.407N     P=0.542      |
|POLY 3             |                                                        |P=0.383      P=0.363N     P=0.415N     P=0.580      |
|POLY 1.5           |                                                        |P=0.390      P=0.372N     P=0.408N     P=0.583      |
|POLY 6             |                                                        |P=0.384      P=0.355N     P=0.424N     P=0.583      |
|LOGISTIC REGRESSION|                                                        |P=0.382      P=0.379N     P=0.401N     P=0.586      |
|COCH-ARM / FISHERS |                                                        |P=0.419      P=0.387N     P=0.387N     P=0.607N     |
|=================================================================================================================================|
       Date:  10/01/97                           EXPERIMENT: 05135 TEST: 07                                            Page 22
                     Statistical Analysis of Primary Tumors in Rats(FISCHER344)       -                      ISOPRENE
                                         Terminal Sacrifice at 104 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|All Organs                                                                                                                       |
|     Leukemia: Lymphocytic, Monocytic, Mononuclear, or                                                                           |
|     Undifferentiated                                                                                                            |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     24/50 (48%)  26/50 (52%)  25/50 (50%)  25/50 (50%) |14/50 (28%)  15/50 (30%)  21/50 (42%)  21/50 (42%)  |
|POLY-3 ADJUSTED (b)|     57.5%        61.9%        58.8%        59.3%       |30.6%        32.1%        45.6%        46.0%        |
|TERMINAL (d)       |     9/18 (50%)   12/16 (75%)  8/15 (53%)   8/15 (53%)  |3/29 (10%)   6/30 (20%)   7/28 (25%)   9/27 (33%)   |
|FIRST INCIDENCE    |     468          499          510          361         |539          370          427          415          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.484      P=0.340      P=0.362      P=0.386     |P=0.121      P=0.543      P=0.128      P=0.108      |
|POLY 3             |     P=0.565N     P=0.424      P=0.542      P=0.525     |P=0.120      P=0.530      P=0.102      P=0.095      |
|POLY 1.5           |     P=0.548      P=0.438      P=0.540      P=0.508     |P=0.121      P=0.523      P=0.099      P=0.094      |
|POLY 6             |     P=0.554N     P=0.380      P=0.522      P=0.521     |P=0.122      P=0.526      P=0.104      P=0.096      |
|LOGISTIC REGRESSION|     P=0.552      P=0.464      P=0.526      P=0.512     |P=0.175      P=0.449      P=0.114      P=0.123      |
|COCH-ARM / FISHERS |     P=0.557      P=0.421      P=0.500      P=0.500     |P=0.140      P=0.500      P=0.104      P=0.104      |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|All Organs                                                                                                                       |
|     Mesothelioma: Benign, Malignant, NOS                                                                                        |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     5/50 (10%)   3/50 (6%)    2/50 (4%)    4/50 (8%)   |0/50 (0%)    0/50 (0%)    0/50 (0%)    1/50 (2%)    |
|POLY-3 ADJUSTED (b)|     13.3%        7.9%         5.3%         10.4%       |0.0%         0.0%         0.0%         2.4%         |
|TERMINAL (d)       |     3/18 (17%)   1/16 (6%)    1/15 (7%)    0/15 (0%)   |0/29 (0%)    0/30 (0%)    0/28 (0%)    0/27 (0%)    |
|FIRST INCIDENCE    |     539          657          566          478         |---          ---          ---          664          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.520      P=0.396N     P=0.256N     P=0.527N    |P=0.248      (e)          (e)          P=0.495      |
|POLY 3             |     P=0.544      P=0.353N     P=0.216N     P=0.489N    |P=0.251      (e)          (e)          P=0.492      |
|POLY 1.5           |     P=0.531      P=0.350N     P=0.212N     P=0.495N    |P=0.253      (e)          (e)          P=0.494      |
|POLY 6             |     P=0.557      P=0.368N     P=0.229N     P=0.492N    |P=0.250      (e)          (e)          P=0.491      |
|LOGISTIC REGRESSION|     P=0.529      P=0.347N     P=0.213N     P=0.499N    |P=0.265      (e)          (e)          P=0.505      |
|COCH-ARM / FISHERS |     P=0.531      P=0.357N     P=0.218N     P=0.500N    |P=0.260      (e)          (e)          P=0.500      |
|=================================================================================================================================|
       Date:  10/01/97                           EXPERIMENT: 05135 TEST: 07                                            Page 23
                     Statistical Analysis of Primary Tumors in Rats(FISCHER344)       -                      ISOPRENE
                                         Terminal Sacrifice at 104 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|All Organs                                                                                                                       |
|     Osteosarcoma or Osteoma                                                                                                     |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     0/50 (0%)    2/50 (4%)    0/50 (0%)    1/50 (2%)   |0/50 (0%)    0/50 (0%)    0/50 (0%)    0/50 (0%)    |
|POLY-3 ADJUSTED (b)|     0.0%         5.3%         0.0%         2.7%        |0.0%         0.0%         0.0%         0.0%         |
|TERMINAL (d)       |     0/18 (0%)    1/16 (6%)    0/15 (0%)    0/15 (0%)   |0/29 (0%)    0/30 (0%)    0/28 (0%)    0/27 (0%)    |
|FIRST INCIDENCE    |     ---          581          ---          727         |---          ---          ---          ---          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.626      P=0.238      (e)          P=0.478     |(e)          (e)          (e)          (e)          |
|POLY 3             |     P=0.635      P=0.244      (e)          P=0.503     |(e)          (e)          (e)          (e)          |
|POLY 1.5           |     P=0.631      P=0.243      (e)          P=0.501     |(e)          (e)          (e)          (e)          |
|POLY 6             |     P=0.636      P=0.241      (e)          P=0.501     |(e)          (e)          (e)          (e)          |
|LOGISTIC REGRESSION|     P=0.630      P=0.239      (e)          P=0.481     |(e)          (e)          (e)          (e)          |
|COCH-ARM / FISHERS |     P=0.629      P=0.247      (e)          P=0.500     |(e)          (e)          (e)          (e)          |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|All Organs                                                                                                                       |
|     Benign Tumors                                                                                                               |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     49/50 (98%)  50/50 (100%) 49/50 (98%)  48/50 (96%) |43/50 (86%)  43/50 (86%)  46/50 (92%)  41/50 (82%)  |
|POLY-3 ADJUSTED (b)|     99.9%        100.0%       99.3%        99.9%       |91.5%        88.6%        97.9%        90.2%        |
|TERMINAL (d)       |     18/18 (100%) 16/16 (100%) 15/15 (100%) 15/15 (100%)|28/29 (97%)  27/30 (90%)  28/28 (100%) 25/27 (93%)  |
|FIRST INCIDENCE    |     342          398          454          361         |454          482          510          432          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.522N     P=0.375      P=0.360      P=0.452     |P=0.523      P=0.454N     P=0.277      P=0.511      |
|POLY 3             |     P=0.996      P=1.000      P=0.968N     P=1.000     |P=0.458N     P=0.442N     P=0.128      P=0.564N     |
|POLY 1.5           |     P=0.939      P=1.000      P=0.823N     P=1.000     |P=0.376N     P=0.522N     P=0.144      P=0.527N     |
|POLY 6             |     P=1.000      P=1.000      P=1.000N     P=1.000     |P=0.528N     P=0.349N     P=0.141      P=0.573N     |
|LOGISTIC REGRESSION|     P=0.771      (e)          P=0.452N     (e)         |P=0.456N     P=0.512N     P=0.134      P=0.596N     |
|COCH-ARM / FISHERS |     P=0.264N     P=0.500      P=0.753N     P=0.500N    |P=0.223N     P=0.613N     P=0.262      P=0.393N     |
|=================================================================================================================================|
       Date:  10/01/97                           EXPERIMENT: 05135 TEST: 07                                            Page 24
                     Statistical Analysis of Primary Tumors in Rats(FISCHER344)       -                      ISOPRENE
                                         Terminal Sacrifice at 104 weeks 
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|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
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|                                                                                                                                 |
|All Organs                                                                                                                       |
|     Malignant Tumors                                                                                                            |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     34/50 (68%)  33/50 (66%)  30/50 (60%)  34/50 (68%) |28/50 (56%)  27/50 (54%)  26/50 (52%)  31/50 (62%)  |
|POLY-3 ADJUSTED (b)|     76.4%        73.5%        66.6%        75.0%       |58.0%        55.5%        56.4%        64.9%        |
|TERMINAL (d)       |     15/18 (83%)  12/16 (75%)  9/15 (60%)   9/15 (60%)  |12/29 (41%)  12/30 (40%)  11/28 (39%)  13/27 (48%)  |
|FIRST INCIDENCE    |     235          398          454          361         |398          370          427          415          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.393      P=0.510      P=0.485N     P=0.430     |P=0.175      P=0.442N     P=0.493N     P=0.292      |
|POLY 3             |     P=0.456      P=0.470N     P=0.197N     P=0.539N    |P=0.200      P=0.484N     P=0.521N     P=0.312      |
|POLY 1.5           |     P=0.401      P=0.477N     P=0.217N     P=0.591N    |P=0.194      P=0.486N     P=0.493N     P=0.310      |
|POLY 6             |     P=0.536      P=0.472N     P=0.188N     P=0.477N    |P=0.214      P=0.492N     P=0.553N     P=0.318      |
|LOGISTIC REGRESSION|     P=0.407      P=0.465N     P=0.257N     P=0.586     |P=0.258      P=0.574N     P=0.404N     P=0.392      |
|COCH-ARM / FISHERS |     P=0.424      P=0.500N     P=0.266N     P=0.585N    |P=0.213      P=0.500N     P=0.421N     P=0.342      |
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|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     CONTROL      220 PPM      700 PPM      7000 PPM    |CONTROL      220 PPM      700 PPM      7000 PPM     |
|                   |                                                        |                                                    |
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|                                                                                                                                 |
|All Organs                                                                                                                       |
|     Malignant and Benign Tumors                                                                                                 |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     50/50 (100%) 50/50 (100%) 49/50 (98%)  48/50 (96%) |49/50 (98%)  48/50 (96%)  49/50 (98%)  48/50 (96%)  |
|POLY-3 ADJUSTED (b)|     100.0%       100.0%       99.3%        99.9%       |98.0%        96.0%        100.0%       98.0%        |
|TERMINAL (d)       |     18/18 (100%) 16/16 (100%) 15/15 (100%) 15/15 (100%)|28/29 (97%)  28/30 (93%)  28/28 (100%) 26/27 (96%)  |
|FIRST INCIDENCE    |     235          398          454          361         |398          370          427          415          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.499N     (e)          P=0.408      P=0.501     |P=0.345      P=0.390N     P=0.466      P=0.431      |
|POLY 3             |     P=0.997      (e)          P=0.961N     P=1.000N    |P=0.680      P=0.500N     P=0.505      P=0.755N     |
|POLY 1.5           |     P=0.950N     (e)          P=0.746N     P=1.000N    |P=0.694      P=0.500N     P=0.527      P=0.742N     |
|POLY 6             |     P=1.000      (e)          P=1.000N     P=1.000N    |P=0.680      P=0.500N     P=0.504      P=0.756N     |
|LOGISTIC REGRESSION|     P=0.545N     (e)          P=0.423N     (e)         |P=0.651N     (e)          P=0.626      P=0.645N     |
|COCH-ARM / FISHERS |     P=0.131N     (e)          P=0.500N     P=0.247N    |P=0.494N     P=0.500N     P=0.753N     P=0.500N     |
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(a)  Number of tumor-bearing animals /  number of animals examined at site.
(b)  Poly-3 adjusted lifetime tumor incidence.
(d)  Observed incidence at terminal kill.
(f)  Beneath the control incidence are the P-values associated with the trend 
test.  Beneath the dosed group incidence are the P-values corresponding to 
pairwise comparisons between the controls and that dosed group.  The life
table analysis regards tumors in animals dying prior to  terminal kill as
 being (directly or indirectly) the cause of death.
Logistic regression is an alternative
 method for analyzing the incidence of non-fatal tumors. The Cochran-Armitage
and Fishers exact tests compare directly the overall incidence rates
For all tests a negative trend is indicated by N
(e)  Value of Statistic cannot be computed.
(I)  Interim sacrifice
(T)  Terminal sacrifice
#   Tumor rates based on number of animals necropsied.
*   To the right of any statistical result, indicates significance at (P<=0.05).
**  To the right of any statistical result, indicates significance at (P<=0.01).
NTP is located at the National Institute of Environmental Health Sciences, part of the National Institutes of Health.