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TDMS Study 88050-05 Pathology Tables

NTP                                        STATISTICAL ANALYSIS OF PRIMARY TUMORS                              REPORT: PEIRPT08     
LAB: Battelle Columbus                                     METHACRYLONITRILE                                   DATE: 02/24/00       
EXPERIMENT: 88050 TEST: 05                                                                                     TIME: 14:19:04       
TEST TYPE:  CHRONIC                             CAGES FROM 0000 TO LAST CAGE                                   PAGE:       1        
CONT: NO1-ES-55388                              ROUTE: GAVAGE                                                  NTP C#: 88050B       
PATHOLOGIST: YARRINGTON, JOHN                                                                                  CAS: 126-98-7        
------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                                    
                                                    FINAL#1 2 YEAR CHRONIC RATS                                                     
                                                                                                                                    

               REASONS FOR REMOVAL:    ALL                                                                                          
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
                                                                                                                                    
               REMOVAL DATE RANGE:     ALL                                                                                          
                                                                                                                                    
               TREATMENT GROUPS:       INCLUDE ALL                                                                                  
NTP                                        STATISTICAL ANALYSIS OF PRIMARY TUMORS                              REPORT: PEIRPT08
LAB: Battelle Columbus                                     METHACRYLONITRILE                                   DATE: 02/24/00

EXPERIMENT: 88050 TEST: 05                                                                                     TIME: 14:19:04
TEST TYPE:  CHRONIC                             CAGES FROM 0000 TO LAST CAGE
CONT: NO1-ES-55388                              ROUTE: GAVAGE                                                  NTP C#: 88050B
PATHOLOGIST: YARRINGTON, JOHN                                                                                  CAS: 126-98-7

Rats(FISCHER 344)
-----------------------------
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 THE NUMBER OF ANIMALS NECROPSIED.
                                                 ---------------
                                                 Adrenal Cortex
                                                 Adrenal Medulla
                                                 Brain
                                                 Clitoral/Preputial Gland
                                                 Heart
                                                 Islets, Pancreatic
                                                 Kidney
                                                 Liver
                                                 Lung
                                                 Nose
                                                 Ovary
                                                 Pancreas
                                                 Parathyroid Gland
                                                 Pituitary Gland
                                                 Prostate
                                                 Salivary Glands
                                                 Spleen
                                                 Testes
                                                 Thyroid Gland
                                                 Urinary Bladder
NTP                                        STATISTICAL ANALYSIS OF PRIMARY TUMORS                              REPORT: PEIRPT08   
LAB: Battelle Columbus                                     METHACRYLONITRILE                                   DATE: 02/24/00     
EXPERIMENT: 88050 TEST: 05                                                                                     TIME: 14:19:04     
TEST TYPE:  CHRONIC                             CAGES FROM 0000 TO LAST CAGE                                                      
CONT: NO1-ES-55388                              ROUTE: GAVAGE                                                  NTP C#: 88050B     
PATHOLOGIST: YARRINGTON, JOHN                                                                                  CAS: 126-98-7      



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

Male Rats
------------
Organ                                 Morphology
-----                                 ----------
Mammary Gland                          Fibroadenoma
                                       Fibroma, Fibroadenoma or Adenoma
                                       Fibroma, Fibroadenoma, Carcinoma, or Adenoma
Testes                                 Adenoma
All Organs                             Leukemia: Lymphocytic, Monocytic, Mononuclear, or Undifferentiated
                                       Malignant and Benign Tumors
===============================================================
Female Rats
------------
Organ                                  Morphology
-----                                  ----------
Lung                                   Alveolar/Bronchiolar Adenoma
                                       Alveolar/Bronchiolar Carcinoma or Alveolar/Bronchiolar Adenoma
Pituitary Gland: Pars Distalis or Unspecified Site
                                       Adenoma
Skin                                   Fibroma
                                       Fibroma, Fibrosarcoma, Sarcoma, Myxoma, Myxosarcoma, or Fibrous Histiocytoma
===============================================================
       Date:  02/24/00                           EXPERIMENT: 88050 TEST: 05                                            Page 1
                     Statistical Analysis of Primary Tumors in Rats(FISCHER 344)        -                 METHACRYLONITRILE
                                         Terminal Sacrifice at 105 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Adrenal Cortex                                                                                                                   |
|     Adenoma                                                                                                                     |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     1/50 (2%)    2/50 (4%)    0/50 (0%)    0/50 (0%)   |1/50 (2%)    0/50 (0%)    0/50 (0%)    0/50 (0%)    |
|POLY-3 ADJUSTED (b)|     2.4%         4.4%         0.0%         0.0%        |2.1%         0.0%         0.0%         0.0%         |
|TERMINAL (d)       |     1/25 (4%)    1/34 (3%)    0/35 (0%)    0/31 (0%)   |1/38 (3%)    0/33 (0%)    0/34 (0%)    0/36 (0%)    |
|FIRST INCIDENCE    |     729 (T)      592          ---          ---         |731 (T)      ---          ---          ---          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.197N     P=0.584      P=0.433N     P=0.457N    |P=0.474N     P=0.528N     P=0.522N     P=0.511N     |
|POLY 3             |     P=0.203N     P=0.537      P=0.483N     P=0.490N    |P=0.463N     P=0.513N     P=0.516N     P=0.511N     |
|POLY 1.5           |     P=0.205N     P=0.524      P=0.490N     P=0.493N    |P=0.467N     P=0.508N     P=0.511N     P=0.507N     |
|POLY 6             |     P=0.200N     P=0.555      P=0.473N     P=0.484N    |P=0.459N     P=0.519N     P=0.520N     P=0.515N     |
|LOGISTIC REGRESSION|     P=0.209N     P=0.502      (e)          (e)         |P=0.474N     (e)          (e)          (e)          |
|COCH-ARM / FISHERS |     P=0.209N     P=0.500      P=0.500N     P=0.500N    |P=0.474N     P=0.500N     P=0.500N     P=0.500N     |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Adrenal Medulla                                                                                                                  |
|     Pheochromocytoma Benign                                                                                                     |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     3/50 (6%)    7/50 (14%)   6/50 (12%)   2/50 (4%)   |1/50 (2%)    3/50 (6%)    2/50 (4%)    1/50 (2%)    |
|POLY-3 ADJUSTED (b)|     7.3%         15.5%        13.5%        4.6%        |2.1%         6.8%         4.7%         2.3%         |
|TERMINAL (d)       |     2/25 (8%)    6/34 (18%)   6/35 (17%)   1/31 (3%)   |0/38 (0%)    2/33 (6%)    2/34 (6%)    1/36 (3%)    |
|FIRST INCIDENCE    |     716          697          729 (T)      680         |718          441          731 (T)      731 (T)      |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.152N     P=0.299      P=0.425      P=0.415N    |P=0.421N     P=0.270      P=0.456      P=0.743      |
|POLY 3             |     P=0.167N     P=0.199      P=0.283      P=0.475N    |P=0.440N     P=0.288      P=0.471      P=0.748      |
|POLY 1.5           |     P=0.172N     P=0.185      P=0.266      P=0.483N    |P=0.433N     P=0.295      P=0.480      P=0.752      |
|POLY 6             |     P=0.158N     P=0.221      P=0.310      P=0.461N    |P=0.447N     P=0.279      P=0.464      P=0.743      |
|LOGISTIC REGRESSION|     P=0.164N     P=0.249      P=0.387      P=0.458N    |P=0.416N     P=0.363      P=0.461      P=0.746      |
|COCH-ARM / FISHERS |     P=0.185N     P=0.159      P=0.243      P=0.500N    |P=0.419N     P=0.309      P=0.500      P=0.753N     |
|=================================================================================================================================|
       Date:  02/24/00                           EXPERIMENT: 88050 TEST: 05                                            Page 2
                     Statistical Analysis of Primary Tumors in Rats(FISCHER 344)       -                 METHACRYLONITRILE
                                         Terminal Sacrifice at 105 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Adrenal Medulla                                                                                                                  |
|     Pheochromocytoma Malignant                                                                                                  |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     1/50 (2%)    1/50 (2%)    2/50 (4%)    0/50 (0%)   |0/50 (0%)    0/50 (0%)    0/50 (0%)    0/50 (0%)    |
|POLY-3 ADJUSTED (b)|     2.4%         2.2%         4.5%         0.0%        |0.0%         0.0%         0.0%         0.0%         |
|TERMINAL (d)       |     1/25 (4%)    0/34 (0%)    2/35 (6%)    0/31 (0%)   |0/38 (0%)    0/33 (0%)    0/34 (0%)    0/36 (0%)    |
|FIRST INCIDENCE    |     729 (T)      536          729 (T)      ---         |---          ---          ---          ---          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.320N     P=0.719N     P=0.617      P=0.457N    |(e)          (e)          (e)          (e)          |
|POLY 3             |     P=0.333N     P=0.736N     P=0.529      P=0.490N    |(e)          (e)          (e)          (e)          |
|POLY 1.5           |     P=0.332N     P=0.744N     P=0.517      P=0.493N    |(e)          (e)          (e)          (e)          |
|POLY 6             |     P=0.332N     P=0.724N     P=0.547      P=0.484N    |(e)          (e)          (e)          (e)          |
|LOGISTIC REGRESSION|     P=0.334N     P=0.735      P=0.617      (e)         |(e)          (e)          (e)          (e)          |
|COCH-ARM / FISHERS |     P=0.333N     P=0.753N     P=0.500      P=0.500N    |(e)          (e)          (e)          (e)          |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Adrenal Medulla                                                                                                                  |
|     Pheochromocytoma: Benign, Complex, Malignant, NOS                                                                           |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     4/50 (8%)    8/50 (16%)   8/50 (16%)   2/50 (4%)   |1/50 (2%)    3/50 (6%)    2/50 (4%)    1/50 (2%)    |
|POLY-3 ADJUSTED (b)|     9.8%         17.5%        18.0%        4.6%        |2.1%         6.8%         4.7%         2.3%         |
|TERMINAL (d)       |     3/25 (12%)   6/34 (18%)   8/35 (23%)   1/31 (3%)   |0/38 (0%)    2/33 (6%)    2/34 (6%)    1/36 (3%)    |
|FIRST INCIDENCE    |     716          536          729 (T)      680         |718          441          731 (T)      731 (T)      |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.089N     P=0.335      P=0.372      P=0.254N    |P=0.421N     P=0.270      P=0.456      P=0.743      |
|POLY 3             |     P=0.101N     P=0.235      P=0.217      P=0.311N    |P=0.440N     P=0.288      P=0.471      P=0.748      |
|POLY 1.5           |     P=0.104N     P=0.213      P=0.201      P=0.320N    |P=0.433N     P=0.295      P=0.480      P=0.752      |
|POLY 6             |     P=0.095N     P=0.264      P=0.245      P=0.297N    |P=0.447N     P=0.279      P=0.464      P=0.743      |
|LOGISTIC REGRESSION|     P=0.104N     P=0.232      P=0.333      P=0.290N    |P=0.416N     P=0.363      P=0.461      P=0.746      |
|COCH-ARM / FISHERS |     P=0.114N     P=0.178      P=0.178      P=0.339N    |P=0.419N     P=0.309      P=0.500      P=0.753N     |
|=================================================================================================================================|
       Date:  02/24/00                           EXPERIMENT: 88050 TEST: 05                                            Page 3
                     Statistical Analysis of Primary Tumors in Rats(FISCHER 344)       -                 METHACRYLONITRILE
                                         Terminal Sacrifice at 105 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Bone                                                                                                                             |
|     Osteosarcoma or Osteoma                                                                                                     |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     1/50 (2%)    2/50 (4%)    0/50 (0%)    0/50 (0%)   |0/50 (0%)    0/50 (0%)    0/50 (0%)    0/50 (0%)    |
|POLY-3 ADJUSTED (b)|     2.4%         4.4%         0.0%         0.0%        |0.0%         0.0%         0.0%         0.0%         |
|TERMINAL (d)       |     0/25 (0%)    1/34 (3%)    0/35 (0%)    0/31 (0%)   |0/38 (0%)    0/33 (0%)    0/34 (0%)    0/36 (0%)    |
|FIRST INCIDENCE    |     474          716          ---          ---         |---          ---          ---          ---          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.201N     P=0.566      P=0.500N     P=0.500N    |(e)          (e)          (e)          (e)          |
|POLY 3             |     P=0.205N     P=0.528      P=0.487N     P=0.493N    |(e)          (e)          (e)          (e)          |
|POLY 1.5           |     P=0.206N     P=0.519      P=0.492N     P=0.495N    |(e)          (e)          (e)          (e)          |
|POLY 6             |     P=0.202N     P=0.541      P=0.478N     P=0.489N    |(e)          (e)          (e)          (e)          |
|LOGISTIC REGRESSION|     P=0.218N     P=0.451      P=0.591N     P=0.605N    |(e)          (e)          (e)          (e)          |
|COCH-ARM / FISHERS |     P=0.209N     P=0.500      P=0.500N     P=0.500N    |(e)          (e)          (e)          (e)          |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Clitoral/Preputial Gland                                                                                                         |
|     Adenoma                                                                                                                     |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     2/50 (4%)    1/50 (2%)    4/50 (8%)    4/49 (8%)   |2/49 (4%)    0/48 (0%)    0/50 (0%)    0/48 (0%)    |
|POLY-3 ADJUSTED (b)|     4.9%         2.2%         9.0%         9.5%        |4.4%         0.0%         0.0%         0.0%         |
|TERMINAL (d)       |     2/25 (8%)    1/34 (3%)    4/35 (11%)   3/30 (10%)  |2/37 (5%)    0/31 (0%)    0/34 (0%)    0/34 (0%)    |
|FIRST INCIDENCE    |     729 (T)      729 (T)      729 (T)      681         |731 (T)      ---          ---          ---          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.181      P=0.393N     P=0.500      P=0.418     |P=0.246N     P=0.278N     P=0.257N     P=0.257N     |
|POLY 3             |     P=0.169      P=0.466N     P=0.376      P=0.352     |P=0.231N     P=0.258N     P=0.251N     P=0.255N     |
|POLY 1.5           |     P=0.170      P=0.478N     P=0.360      P=0.344     |P=0.235N     P=0.252N     P=0.245N     P=0.251N     |
|POLY 6             |     P=0.170      P=0.451N     P=0.401      P=0.365     |P=0.227N     P=0.265N     P=0.255N     P=0.260N     |
|LOGISTIC REGRESSION|     P=0.173      P=0.393N     P=0.500      P=0.375     |P=0.246N     (e)          (e)          (e)          |
|COCH-ARM / FISHERS |     P=0.170      P=0.500N     P=0.339      P=0.329     |P=0.243N     P=0.253N     P=0.242N     P=0.253N     |
|=================================================================================================================================|
       Date:  02/24/00                           EXPERIMENT: 88050 TEST: 05                                            Page 4
                     Statistical Analysis of Primary Tumors in Rats(FISCHER 344)       -                 METHACRYLONITRILE
                                         Terminal Sacrifice at 105 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Clitoral/Preputial Gland                                                                                                         |
|     Carcinoma                                                                                                                   |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     1/50 (2%)    1/50 (2%)    3/50 (6%)    2/49 (4%)   |1/49 (2%)    2/48 (4%)    1/50 (2%)    0/48 (0%)    |
|POLY-3 ADJUSTED (b)|     2.4%         2.2%         6.6%         4.6%        |2.2%         4.8%         2.3%         0.0%         |
|TERMINAL (d)       |     0/25 (0%)    1/34 (3%)    1/35 (3%)    0/30 (0%)   |0/37 (0%)    2/31 (7%)    1/34 (3%)    0/34 (0%)    |
|FIRST INCIDENCE    |     579          729 (T)      464          466         |438          731 (T)      731 (T)      ---          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.403      P=0.716N     P=0.366      P=0.514     |P=0.237N     P=0.457      P=0.744      P=0.504N     |
|POLY 3             |     P=0.402      P=0.741N     P=0.338      P=0.514     |P=0.249N     P=0.462      P=0.743      P=0.519N     |
|POLY 1.5           |     P=0.399      P=0.748N     P=0.325      P=0.507     |P=0.244N     P=0.474      P=0.750      P=0.514N     |
|POLY 6             |     P=0.408      P=0.733N     P=0.358      P=0.524     |P=0.255N     P=0.450      P=0.738      P=0.524N     |
|LOGISTIC REGRESSION|     P=0.360      P=0.748      P=0.258      P=0.415     |P=0.219N     P=0.586      P=0.664N     P=0.260N     |
|COCH-ARM / FISHERS |     P=0.390      P=0.753N     P=0.309      P=0.492     |P=0.233N     P=0.492      P=0.747N     P=0.505N     |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Clitoral/Preputial Gland                                                                                                         |
|     Carcinoma or Adenoma                                                                                                        |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     3/50 (6%)    2/50 (4%)    7/50 (14%)   6/49 (12%)  |3/49 (6%)    2/48 (4%)    1/50 (2%)    0/48 (0%)    |
|POLY-3 ADJUSTED (b)|     7.2%         4.4%         15.4%        13.9%       |6.5%         4.8%         2.3%         0.0%         |
|TERMINAL (d)       |     2/25 (8%)    2/34 (6%)    5/35 (14%)   3/30 (10%)  |2/37 (5%)    2/31 (7%)    1/34 (3%)    0/34 (0%)    |
|FIRST INCIDENCE    |     579          729 (T)      464          466         |438          731 (T)      731 (T)      ---          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.141      P=0.381N     P=0.289      P=0.313     |P=0.090N     P=0.566N     P=0.335N     P=0.134N     |
|POLY 3             |     P=0.132      P=0.461N     P=0.196      P=0.263     |P=0.090N     P=0.549N     P=0.333N     P=0.137N     |
|POLY 1.5           |     P=0.129      P=0.474N     P=0.181      P=0.253     |P=0.089N     P=0.534N     P=0.322N     P=0.132N     |
|POLY 6             |     P=0.137      P=0.445N     P=0.221      P=0.279     |P=0.091N     P=0.565N     P=0.342N     P=0.142N     |
|LOGISTIC REGRESSION|     P=0.125      P=0.470N     P=0.163      P=0.229     |P=0.084N     P=0.461N     P=0.240N     P=0.076N     |
|COCH-ARM / FISHERS |     P=0.125      P=0.500N     P=0.159      P=0.233     |P=0.087N     P=0.510N     P=0.301N     P=0.125N     |
|=================================================================================================================================|
       Date:  02/24/00                           EXPERIMENT: 88050 TEST: 05                                            Page 5
                     Statistical Analysis of Primary Tumors in Rats(FISCHER 344)       -                 METHACRYLONITRILE
                                         Terminal Sacrifice at 105 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Islets, Pancreatic                                                                                                               |
|     Adenoma                                                                                                                     |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     0/50 (0%)    2/50 (4%)    1/50 (2%)    1/50 (2%)   |0/50 (0%)    1/50 (2%)    1/50 (2%)    0/50 (0%)    |
|POLY-3 ADJUSTED (b)|     0.0%         4.4%         2.3%         2.3%        |0.0%         2.3%         2.3%         0.0%         |
|TERMINAL (d)       |     0/25 (0%)    2/34 (6%)    1/35 (3%)    0/31 (0%)   |0/38 (0%)    1/33 (3%)    1/34 (3%)    0/36 (0%)    |
|FIRST INCIDENCE    |     ---          729 (T)      729 (T)      680         |---          731 (T)      731 (T)      ---          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.638      P=0.308      P=0.567      P=0.528     |P=0.535N     P=0.472      P=0.478      (e)          |
|POLY 3             |     P=0.638      P=0.259      P=0.516      P=0.511     |P=0.550N     P=0.487      P=0.484      (e)          |
|POLY 1.5           |     P=0.631      P=0.252      P=0.510      P=0.507     |P=0.546N     P=0.492      P=0.489      (e)          |
|POLY 6             |     P=0.648      P=0.270      P=0.527      P=0.517     |P=0.555N     P=0.481      P=0.480      (e)          |
|LOGISTIC REGRESSION|     P=0.625      P=0.308      P=0.567      P=0.502     |(e)          P=0.472      P=0.478      (e)          |
|COCH-ARM / FISHERS |     P=0.619      P=0.247      P=0.500      P=0.500     |P=0.536N     P=0.500      P=0.500      (e)          |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Islets, Pancreatic                                                                                                               |
|     Carcinoma                                                                                                                   |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     0/50 (0%)    2/50 (4%)    0/50 (0%)    0/50 (0%)   |0/50 (0%)    0/50 (0%)    0/50 (0%)    0/50 (0%)    |
|POLY-3 ADJUSTED (b)|     0.0%         4.4%         0.0%         0.0%        |0.0%         0.0%         0.0%         0.0%         |
|TERMINAL (d)       |     0/25 (0%)    2/34 (6%)    0/35 (0%)    0/31 (0%)   |0/38 (0%)    0/33 (0%)    0/34 (0%)    0/36 (0%)    |
|FIRST INCIDENCE    |     ---          729 (T)      ---          ---         |---          ---          ---          ---          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.353N     P=0.308      (e)          (e)         |(e)          (e)          (e)          (e)          |
|POLY 3             |     P=0.348N     P=0.259      (e)          (e)         |(e)          (e)          (e)          (e)          |
|POLY 1.5           |     P=0.355N     P=0.252      (e)          (e)         |(e)          (e)          (e)          (e)          |
|POLY 6             |     P=0.340N     P=0.270      (e)          (e)         |(e)          (e)          (e)          (e)          |
|LOGISTIC REGRESSION|     (e)          P=0.308      (e)          (e)         |(e)          (e)          (e)          (e)          |
|COCH-ARM / FISHERS |     P=0.369N     P=0.247      (e)          (e)         |(e)          (e)          (e)          (e)          |
|=================================================================================================================================|
       Date:  02/24/00                           EXPERIMENT: 88050 TEST: 05                                            Page 6
                     Statistical Analysis of Primary Tumors in Rats(FISCHER 344)       -                 METHACRYLONITRILE
                                         Terminal Sacrifice at 105 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Islets, Pancreatic                                                                                                               |
|     Carcinoma or Adenoma                                                                                                        |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     0/50 (0%)    4/50 (8%)    1/50 (2%)    1/50 (2%)   |0/50 (0%)    1/50 (2%)    1/50 (2%)    0/50 (0%)    |
|POLY-3 ADJUSTED (b)|     0.0%         8.9%         2.3%         2.3%        |0.0%         2.3%         2.3%         0.0%         |
|TERMINAL (d)       |     0/25 (0%)    4/34 (12%)   1/35 (3%)    0/31 (0%)   |0/38 (0%)    1/33 (3%)    1/34 (3%)    0/36 (0%)    |
|FIRST INCIDENCE    |     ---          729 (T)      729 (T)      680         |---          731 (T)      731 (T)      ---          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.440N     P=0.107      P=0.567      P=0.528     |P=0.535N     P=0.472      P=0.478      (e)          |
|POLY 3             |     P=0.436N     P=0.073      P=0.516      P=0.511     |P=0.550N     P=0.487      P=0.484      (e)          |
|POLY 1.5           |     P=0.445N     P=0.069      P=0.510      P=0.507     |P=0.546N     P=0.492      P=0.489      (e)          |
|POLY 6             |     P=0.422N     P=0.080      P=0.527      P=0.517     |P=0.555N     P=0.481      P=0.480      (e)          |
|LOGISTIC REGRESSION|     P=0.455N     P=0.107      P=0.567      P=0.502     |(e)          P=0.472      P=0.478      (e)          |
|COCH-ARM / FISHERS |     P=0.465N     P=0.059      P=0.500      P=0.500     |P=0.536N     P=0.500      P=0.500      (e)          |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Liver                                                                                                                            |
|     Hepatocellular Adenoma                                                                                                      |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     1/50 (2%)    2/50 (4%)    0/50 (0%)    0/49 (0%)   |1/50 (2%)    0/49 (0%)    0/48 (0%)    0/50 (0%)    |
|POLY-3 ADJUSTED (b)|     2.4%         4.4%         0.0%         0.0%        |2.1%         0.0%         0.0%         0.0%         |
|TERMINAL (d)       |     1/25 (4%)    2/34 (6%)    0/35 (0%)    0/31 (0%)   |0/38 (0%)    0/33 (0%)    0/34 (0%)    0/36 (0%)    |
|FIRST INCIDENCE    |     729 (T)      729 (T)      ---          ---         |589          ---          ---          ---          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.192N     P=0.607      P=0.433N     P=0.457N    |P=0.482N     P=0.517N     P=0.522N     P=0.517N     |
|POLY 3             |     P=0.206N     P=0.534      P=0.483N     P=0.493N    |P=0.463N     P=0.516N     P=0.521N     P=0.513N     |
|POLY 1.5           |     P=0.208N     P=0.522      P=0.490N     P=0.497N    |P=0.467N     P=0.511N     P=0.517N     P=0.509N     |
|POLY 6             |     P=0.203N     P=0.549      P=0.473N     P=0.488N    |P=0.458N     P=0.522N     P=0.524N     P=0.518N     |
|LOGISTIC REGRESSION|     P=0.192N     P=0.607      (e)          (e)         |P=0.437N     P=0.424N     P=0.417N     P=0.414N     |
|COCH-ARM / FISHERS |     P=0.213N     P=0.500      P=0.500N     P=0.505N    |P=0.473N     P=0.505N     P=0.510N     P=0.500N     |
|=================================================================================================================================|
       Date:  02/24/00                           EXPERIMENT: 88050 TEST: 05                                            Page 7
                     Statistical Analysis of Primary Tumors in Rats(FISCHER 344)       -                 METHACRYLONITRILE
                                         Terminal Sacrifice at 105 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Lung                                                                                                                             |
|     Alveolar/Bronchiolar Adenoma                                                                                                |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     0/50 (0%)    3/50 (6%)    1/50 (2%)    1/50 (2%)   |0/50 (0%)    0/50 (0%)    0/50 (0%)    2/50 (4%)    |
|POLY-3 ADJUSTED (b)|     0.0%         6.6%         2.3%         2.3%        |0.0%         0.0%         0.0%         4.5%         |
|TERMINAL (d)       |     0/25 (0%)    2/34 (6%)    1/35 (3%)    1/31 (3%)   |0/38 (0%)    0/33 (0%)    0/34 (0%)    1/36 (3%)    |
|FIRST INCIDENCE    |     ---          674          729 (T)      729 (T)     |---          ---          ---          549          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.564N     P=0.175      P=0.567      P=0.543     |P=0.044 *    (e)          (e)          P=0.229      |
|POLY 3             |     P=0.559N     P=0.138      P=0.516      P=0.510     |P=0.040 *    (e)          (e)          P=0.228      |
|POLY 1.5           |     P=0.566N     P=0.131      P=0.510      P=0.507     |P=0.040 *    (e)          (e)          P=0.231      |
|POLY 6             |     P=0.549N     P=0.148      P=0.527      P=0.516     |P=0.040 *    (e)          (e)          P=0.225      |
|LOGISTIC REGRESSION|     P=0.575N     P=0.140      P=0.567      P=0.543     |P=0.044 *    (e)          (e)          P=0.277      |
|COCH-ARM / FISHERS |     P=0.581N     P=0.121      P=0.500      P=0.500     |P=0.042 *    (e)          (e)          P=0.247      |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Lung                                                                                                                             |
|     Alveolar/Bronchiolar Carcinoma or Alveolar/Bronchiolar                                                                      |
|     Adenoma                                                                                                                     |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     0/50 (0%)    3/50 (6%)    1/50 (2%)    1/50 (2%)   |0/50 (0%)    0/50 (0%)    0/50 (0%)    2/50 (4%)    |
|POLY-3 ADJUSTED (b)|     0.0%         6.6%         2.3%         2.3%        |0.0%         0.0%         0.0%         4.5%         |
|TERMINAL (d)       |     0/25 (0%)    2/34 (6%)    1/35 (3%)    1/31 (3%)   |0/38 (0%)    0/33 (0%)    0/34 (0%)    1/36 (3%)    |
|FIRST INCIDENCE    |     ---          674          729 (T)      729 (T)     |---          ---          ---          549          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.564N     P=0.175      P=0.567      P=0.543     |P=0.044 *    (e)          (e)          P=0.229      |
|POLY 3             |     P=0.559N     P=0.138      P=0.516      P=0.510     |P=0.040 *    (e)          (e)          P=0.228      |
|POLY 1.5           |     P=0.566N     P=0.131      P=0.510      P=0.507     |P=0.040 *    (e)          (e)          P=0.231      |
|POLY 6             |     P=0.549N     P=0.148      P=0.527      P=0.516     |P=0.040 *    (e)          (e)          P=0.225      |
|LOGISTIC REGRESSION|     P=0.575N     P=0.140      P=0.567      P=0.543     |P=0.044 *    (e)          (e)          P=0.277      |
|COCH-ARM / FISHERS |     P=0.581N     P=0.121      P=0.500      P=0.500     |P=0.042 *    (e)          (e)          P=0.247      |
|=================================================================================================================================|
       Date:  02/24/00                           EXPERIMENT: 88050 TEST: 05                                            Page 8
                     Statistical Analysis of Primary Tumors in Rats(FISCHER 344)       -                 METHACRYLONITRILE
                                         Terminal Sacrifice at 105 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Mammary Gland                                                                                                                    |
|     Carcinoma                                                                                                                   |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     0/50 (0%)    0/50 (0%)    0/50 (0%)    0/50 (0%)   |3/50 (6%)    1/50 (2%)    1/50 (2%)    1/50 (2%)    |
|POLY-3 ADJUSTED (b)|     0.0%         0.0%         0.0%         0.0%        |6.4%         2.3%         2.3%         2.3%         |
|TERMINAL (d)       |     0/25 (0%)    0/34 (0%)    0/35 (0%)    0/31 (0%)   |3/38 (8%)    0/33 (0%)    1/34 (3%)    1/36 (3%)    |
|FIRST INCIDENCE    |     ---          ---          ---          ---         |731 (T)      609          731 (T)      731 (T)      |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     (e)          (e)          (e)          (e)         |P=0.347N     P=0.353N     P=0.345N     P=0.324N     |
|POLY 3             |     (e)          (e)          (e)          (e)         |P=0.344N     P=0.326N     P=0.335N     P=0.326N     |
|POLY 1.5           |     (e)          (e)          (e)          (e)         |P=0.344N     P=0.318N     P=0.326N     P=0.319N     |
|POLY 6             |     (e)          (e)          (e)          (e)         |P=0.344N     P=0.334N     P=0.342N     P=0.332N     |
|LOGISTIC REGRESSION|     (e)          (e)          (e)          (e)         |P=0.350N     P=0.305N     P=0.345N     P=0.324N     |
|COCH-ARM / FISHERS |     (e)          (e)          (e)          (e)         |P=0.342N     P=0.309N     P=0.309N     P=0.309N     |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Mammary Gland                                                                                                                    |
|     Carcinoma or Adenoma                                                                                                        |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     0/50 (0%)    0/50 (0%)    0/50 (0%)    0/50 (0%)   |3/50 (6%)    1/50 (2%)    1/50 (2%)    1/50 (2%)    |
|POLY-3 ADJUSTED (b)|     0.0%         0.0%         0.0%         0.0%        |6.4%         2.3%         2.3%         2.3%         |
|TERMINAL (d)       |     0/25 (0%)    0/34 (0%)    0/35 (0%)    0/31 (0%)   |3/38 (8%)    0/33 (0%)    1/34 (3%)    1/36 (3%)    |
|FIRST INCIDENCE    |     ---          ---          ---          ---         |731 (T)      609          731 (T)      731 (T)      |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     (e)          (e)          (e)          (e)         |P=0.347N     P=0.353N     P=0.345N     P=0.324N     |
|POLY 3             |     (e)          (e)          (e)          (e)         |P=0.344N     P=0.326N     P=0.335N     P=0.326N     |
|POLY 1.5           |     (e)          (e)          (e)          (e)         |P=0.344N     P=0.318N     P=0.326N     P=0.319N     |
|POLY 6             |     (e)          (e)          (e)          (e)         |P=0.344N     P=0.334N     P=0.342N     P=0.332N     |
|LOGISTIC REGRESSION|     (e)          (e)          (e)          (e)         |P=0.350N     P=0.305N     P=0.345N     P=0.324N     |
|COCH-ARM / FISHERS |     (e)          (e)          (e)          (e)         |P=0.342N     P=0.309N     P=0.309N     P=0.309N     |
|=================================================================================================================================|
       Date:  02/24/00                           EXPERIMENT: 88050 TEST: 05                                            Page 9
                     Statistical Analysis of Primary Tumors in Rats(FISCHER 344)       -                 METHACRYLONITRILE
                                         Terminal Sacrifice at 105 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Mammary Gland                                                                                                                    |
|     Fibroadenoma                                                                                                                |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     2/50 (4%)    7/50 (14%)   2/50 (4%)    8/50 (16%)  |21/50 (42%)  26/50 (52%)  19/50 (38%)  18/50 (36%)  |
|POLY-3 ADJUSTED (b)|     4.9%         15.4%        4.5%         18.5%       |44.9%        57.0%        43.5%        39.5%        |
|TERMINAL (d)       |     0/25 (0%)    5/34 (15%)   2/35 (6%)    7/31 (23%)  |19/38 (50%)  20/33 (61%)  15/34 (44%)  13/36 (36%)  |
|FIRST INCIDENCE    |     724          696          729 (T)      680         |679          527          651          499          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.100      P=0.168      P=0.583N     P=0.092     |P=0.161N     P=0.080      P=0.566      P=0.424N     |
|POLY 3             |     P=0.089      P=0.105      P=0.664N     P=0.053     |P=0.155N     P=0.165      P=0.531N     P=0.378N     |
|POLY 1.5           |     P=0.087      P=0.095      P=0.676N     P=0.051     |P=0.154N     P=0.179      P=0.500N     P=0.369N     |
|POLY 6             |     P=0.092      P=0.119      P=0.645N     P=0.058     |P=0.153N     P=0.155      P=0.547N     P=0.381N     |
|LOGISTIC REGRESSION|     P=0.086      P=0.127      P=0.603N     P=0.067     |P=0.177N     P=0.121      P=0.579      P=0.427N     |
|COCH-ARM / FISHERS |     P=0.084      P=0.080      P=0.691N     P=0.046 *   |P=0.149N     P=0.212      P=0.419N     P=0.341N     |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Mammary Gland                                                                                                                    |
|     Fibroma, Fibroadenoma or Adenoma                                                                                            |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     2/50 (4%)    7/50 (14%)   2/50 (4%)    8/50 (16%)  |21/50 (42%)  26/50 (52%)  19/50 (38%)  18/50 (36%)  |
|POLY-3 ADJUSTED (b)|     4.9%         15.4%        4.5%         18.5%       |44.9%        57.0%        43.5%        39.5%        |
|TERMINAL (d)       |     0/25 (0%)    5/34 (15%)   2/35 (6%)    7/31 (23%)  |19/38 (50%)  20/33 (61%)  15/34 (44%)  13/36 (36%)  |
|FIRST INCIDENCE    |     724          696          729 (T)      680         |679          527          651          499          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.100      P=0.168      P=0.583N     P=0.092     |P=0.161N     P=0.080      P=0.566      P=0.424N     |
|POLY 3             |     P=0.089      P=0.105      P=0.664N     P=0.053     |P=0.155N     P=0.165      P=0.531N     P=0.378N     |
|POLY 1.5           |     P=0.087      P=0.095      P=0.676N     P=0.051     |P=0.154N     P=0.179      P=0.500N     P=0.369N     |
|POLY 6             |     P=0.092      P=0.119      P=0.645N     P=0.058     |P=0.153N     P=0.155      P=0.547N     P=0.381N     |
|LOGISTIC REGRESSION|     P=0.086      P=0.127      P=0.603N     P=0.067     |P=0.177N     P=0.121      P=0.579      P=0.427N     |
|COCH-ARM / FISHERS |     P=0.084      P=0.080      P=0.691N     P=0.046 *   |P=0.149N     P=0.212      P=0.419N     P=0.341N     |
|=================================================================================================================================|
       Date:  02/24/00                           EXPERIMENT: 88050 TEST: 05                                            Page 10
                     Statistical Analysis of Primary Tumors in Rats(FISCHER 344)       -                 METHACRYLONITRILE
                                         Terminal Sacrifice at 105 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Mammary Gland                                                                                                                    |
|     Fibroma, Fibroadenoma, Carcinoma, or Adenoma                                                                                |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     2/50 (4%)    7/50 (14%)   2/50 (4%)    8/50 (16%)  |23/50 (46%)  26/50 (52%)  20/50 (40%)  19/50 (38%)  |
|POLY-3 ADJUSTED (b)|     4.9%         15.4%        4.5%         18.5%       |49.1%        57.0%        45.7%        41.7%        |
|TERMINAL (d)       |     0/25 (0%)    5/34 (15%)   2/35 (6%)    7/31 (23%)  |21/38 (55%)  20/33 (61%)  16/34 (47%)  14/36 (39%)  |
|FIRST INCIDENCE    |     724          696          729 (T)      680         |679          527          651          499          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.100      P=0.168      P=0.583N     P=0.092     |P=0.153N     P=0.149      P=0.529N     P=0.355N     |
|POLY 3             |     P=0.089      P=0.105      P=0.664N     P=0.053     |P=0.147N     P=0.289      P=0.455N     P=0.304N     |
|POLY 1.5           |     P=0.087      P=0.095      P=0.676N     P=0.051     |P=0.147N     P=0.306      P=0.424N     P=0.297N     |
|POLY 6             |     P=0.092      P=0.119      P=0.645N     P=0.058     |P=0.144N     P=0.278      P=0.471N     P=0.306N     |
|LOGISTIC REGRESSION|     P=0.086      P=0.127      P=0.603N     P=0.067     |P=0.171N     P=0.217      P=0.521N     P=0.359N     |
|COCH-ARM / FISHERS |     P=0.084      P=0.080      P=0.691N     P=0.046 *   |P=0.142N     P=0.345      P=0.343N     P=0.272N     |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Pancreas                                                                                                                         |
|     Adenoma                                                                                                                     |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     2/50 (4%)    0/49 (0%)    1/50 (2%)    2/50 (4%)   |0/50 (0%)    0/50 (0%)    0/50 (0%)    0/50 (0%)    |
|POLY-3 ADJUSTED (b)|     4.9%         0.0%         2.3%         4.6%        |0.0%         0.0%         0.0%         0.0%         |
|TERMINAL (d)       |     2/25 (8%)    0/34 (0%)    1/35 (3%)    2/31 (7%)   |0/38 (0%)    0/33 (0%)    0/34 (0%)    0/36 (0%)    |
|FIRST INCIDENCE    |     729 (T)      ---          729 (T)      729 (T)     |---          ---          ---          ---          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.426      P=0.173N     P=0.383N     P=0.616N    |(e)          (e)          (e)          (e)          |
|POLY 3             |     P=0.391      P=0.217N     P=0.471N     P=0.676N    |(e)          (e)          (e)          (e)          |
|POLY 1.5           |     P=0.398      P=0.225N     P=0.483N     P=0.681N    |(e)          (e)          (e)          (e)          |
|POLY 6             |     P=0.385      P=0.207N     P=0.453N     P=0.666N    |(e)          (e)          (e)          (e)          |
|LOGISTIC REGRESSION|     P=0.426      (e)          P=0.383N     P=0.616N    |(e)          (e)          (e)          (e)          |
|COCH-ARM / FISHERS |     P=0.407      P=0.253N     P=0.500N     P=0.691N    |(e)          (e)          (e)          (e)          |
|=================================================================================================================================|
       Date:  02/24/00                           EXPERIMENT: 88050 TEST: 05                                            Page 11
                     Statistical Analysis of Primary Tumors in Rats(FISCHER 344)       -                 METHACRYLONITRILE
                                         Terminal Sacrifice at 105 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Pituitary Gland: Pars Distalis or Unspecified Site                                                                               |
|     Adenoma                                                                                                                     |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     17/50 (34%)  18/50 (36%)  11/50 (22%)  20/50 (40%) |12/50 (24%)  14/50 (28%)  19/50 (38%)  14/50 (28%)  |
|POLY-3 ADJUSTED (b)|     38.0%        39.1%        23.6%        45.4%       |25.7%        31.6%        43.9%        31.3%        |
|TERMINAL (d)       |     8/25 (32%)   13/34 (38%)  7/35 (20%)   14/31 (45%) |10/38 (26%)  10/33 (30%)  16/34 (47%)  13/36 (36%)  |
|FIRST INCIDENCE    |     453          592          464          624         |718          609          690          527          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.359      P=0.337N     P=0.050N     P=0.574N    |P=0.458      P=0.269      P=0.048 *    P=0.347      |
|POLY 3             |     P=0.242      P=0.547      P=0.100N     P=0.312     |P=0.418      P=0.347      P=0.052      P=0.358      |
|POLY 1.5           |     P=0.260      P=0.537      P=0.111N     P=0.330     |P=0.431      P=0.369      P=0.064      P=0.375      |
|POLY 6             |     P=0.229      P=0.565      P=0.085N     P=0.305     |P=0.405      P=0.326      P=0.045 *    P=0.341      |
|LOGISTIC REGRESSION|     P=0.288      P=0.527      P=0.155N     P=0.374     |P=0.405      P=0.298      P=0.039 *    P=0.328      |
|COCH-ARM / FISHERS |     P=0.284      P=0.500      P=0.133N     P=0.339     |P=0.459      P=0.410      P=0.097      P=0.410      |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Pituitary Gland: Pars Distalis or Unspecified Site                                                                               |
|     Carcinoma or Adenoma                                                                                                        |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     17/50 (34%)  18/50 (36%)  11/50 (22%)  20/50 (40%) |13/50 (26%)  14/50 (28%)  19/50 (38%)  14/50 (28%)  |
|POLY-3 ADJUSTED (b)|     38.0%        39.1%        23.6%        45.4%       |27.8%        31.6%        43.9%        31.3%        |
|TERMINAL (d)       |     8/25 (32%)   13/34 (38%)  7/35 (20%)   14/31 (45%) |11/38 (29%)  10/33 (30%)  16/34 (47%)  13/36 (36%)  |
|FIRST INCIDENCE    |     453          592          464          624         |718          609          690          527          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.359      P=0.337N     P=0.050N     P=0.574N    |P=0.514      P=0.342      P=0.073      P=0.432      |
|POLY 3             |     P=0.242      P=0.547      P=0.100N     P=0.312     |P=0.478      P=0.434      P=0.082      P=0.446      |
|POLY 1.5           |     P=0.260      P=0.537      P=0.111N     P=0.330     |P=0.490      P=0.458      P=0.098      P=0.463      |
|POLY 6             |     P=0.229      P=0.565      P=0.085N     P=0.305     |P=0.465      P=0.412      P=0.071      P=0.428      |
|LOGISTIC REGRESSION|     P=0.288      P=0.527      P=0.155N     P=0.374     |P=0.462      P=0.379      P=0.061      P=0.412      |
|COCH-ARM / FISHERS |     P=0.284      P=0.500      P=0.133N     P=0.339     |P=0.516      P=0.500      P=0.142      P=0.500      |
|=================================================================================================================================|
       Date:  02/24/00                           EXPERIMENT: 88050 TEST: 05                                            Page 12
                     Statistical Analysis of Primary Tumors in Rats(FISCHER 344)       -                 METHACRYLONITRILE
                                         Terminal Sacrifice at 105 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Salivary Glands                                                                                                                  |
|     Schwannoma Malignant                                                                                                        |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     2/50 (4%)    0/50 (0%)    1/50 (2%)    1/50 (2%)   |0/50 (0%)    0/50 (0%)    0/50 (0%)    0/50 (0%)    |
|POLY-3 ADJUSTED (b)|     4.8%         0.0%         2.3%         2.3%        |0.0%         0.0%         0.0%         0.0%         |
|TERMINAL (d)       |     0/25 (0%)    0/34 (0%)    1/35 (3%)    0/31 (0%)   |0/38 (0%)    0/33 (0%)    0/34 (0%)    0/36 (0%)    |
|FIRST INCIDENCE    |     563          ---          729 (T)      618         |---          ---          ---          ---          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.614N     P=0.214N     P=0.442N     P=0.480N    |(e)          (e)          (e)          (e)          |
|POLY 3             |     P=0.629N     P=0.220N     P=0.478N     P=0.486N    |(e)          (e)          (e)          (e)          |
|POLY 1.5           |     P=0.625N     P=0.226N     P=0.487N     P=0.490N    |(e)          (e)          (e)          (e)          |
|POLY 6             |     P=0.634N     P=0.214N     P=0.465N     P=0.479N    |(e)          (e)          (e)          (e)          |
|LOGISTIC REGRESSION|     P=0.634N     P=0.285N     P=0.524N     P=0.549N    |(e)          (e)          (e)          (e)          |
|COCH-ARM / FISHERS |     P=0.619N     P=0.247N     P=0.500N     P=0.500N    |(e)          (e)          (e)          (e)          |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Skin                                                                                                                             |
|     Basal Cell Carcinoma, Basal Cell Adenoma, Basosquamous                                                                      |
|     Tumor (benign, malignant or NOS), or Trichoepithelioma                                                                      |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     0/50 (0%)    0/50 (0%)    2/50 (4%)    0/50 (0%)   |1/50 (2%)    1/50 (2%)    0/50 (0%)    0/50 (0%)    |
|POLY-3 ADJUSTED (b)|     0.0%         0.0%         4.5%         0.0%        |2.1%         2.3%         0.0%         0.0%         |
|TERMINAL (d)       |     0/25 (0%)    0/34 (0%)    1/35 (3%)    0/31 (0%)   |1/38 (3%)    0/33 (0%)    0/34 (0%)    0/36 (0%)    |
|FIRST INCIDENCE    |     ---          ---          722          ---         |731 (T)      609          ---          ---          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.684N     (e)          P=0.314      (e)         |P=0.311N     P=0.735      P=0.522N     P=0.511N     |
|POLY 3             |     P=0.696N     (e)          P=0.256      (e)         |P=0.306N     P=0.748      P=0.516N     P=0.511N     |
|POLY 1.5           |     P=0.696N     (e)          P=0.248      (e)         |P=0.305N     P=0.752      P=0.511N     P=0.507N     |
|POLY 6             |     P=0.694N     (e)          P=0.269      (e)         |P=0.307N     P=0.743      P=0.520N     P=0.515N     |
|LOGISTIC REGRESSION|     P=0.692N     (e)          P=0.289      (e)         |P=0.295N     P=0.742N     (e)          (e)          |
|COCH-ARM / FISHERS |     P=0.697N     (e)          P=0.247      (e)         |P=0.303N     P=0.753N     P=0.500N     P=0.500N     |
|=================================================================================================================================|
       Date:  02/24/00                           EXPERIMENT: 88050 TEST: 05                                            Page 13
                     Statistical Analysis of Primary Tumors in Rats(FISCHER 344)       -                 METHACRYLONITRILE
                                         Terminal Sacrifice at 105 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|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)        |     2/50 (4%)    5/50 (10%)   5/50 (10%)   2/50 (4%)   |2/50 (4%)    1/50 (2%)    0/50 (0%)    0/50 (0%)    |
|POLY-3 ADJUSTED (b)|     4.8%         11.0%        11.2%        4.6%        |4.3%         2.3%         0.0%         0.0%         |
|TERMINAL (d)       |     0/25 (0%)    3/34 (9%)    4/35 (11%)   2/31 (7%)   |2/38 (5%)    0/33 (0%)    0/34 (0%)    0/36 (0%)    |
|FIRST INCIDENCE    |     579          674          722          729 (T)     |731 (T)      609          ---          ---          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.330N     P=0.326      P=0.340      P=0.644N    |P=0.176N     P=0.543N     P=0.263N     P=0.250N     |
|POLY 3             |     P=0.349N     P=0.253      P=0.243      P=0.682N    |P=0.168N     P=0.520N     P=0.256N     P=0.250N     |
|POLY 1.5           |     P=0.349N     P=0.241      P=0.233      P=0.685N    |P=0.168N     P=0.513N     P=0.250N     P=0.246N     |
|POLY 6             |     P=0.347N     P=0.270      P=0.261      P=0.677N    |P=0.168N     P=0.527N     P=0.260N     P=0.254N     |
|LOGISTIC REGRESSION|     P=0.351N     P=0.218      P=0.237      P=0.694N    |P=0.168N     P=0.487N     (e)          (e)          |
|COCH-ARM / FISHERS |     P=0.357N     P=0.218      P=0.218      P=0.691N    |P=0.169N     P=0.500N     P=0.247N     P=0.247N     |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Skin                                                                                                                             |
|     Fibroma                                                                                                                     |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     3/50 (6%)    4/50 (8%)    2/50 (4%)    5/50 (10%)  |0/50 (0%)    0/50 (0%)    0/50 (0%)    2/50 (4%)    |
|POLY-3 ADJUSTED (b)|     7.3%         8.8%         4.5%         11.6%       |0.0%         0.0%         0.0%         4.5%         |
|TERMINAL (d)       |     2/25 (8%)    2/34 (6%)    2/35 (6%)    5/31 (16%)  |0/38 (0%)    0/33 (0%)    0/34 (0%)    2/36 (6%)    |
|FIRST INCIDENCE    |     701          641          729 (T)      729 (T)     |---          ---          ---          731 (T)      |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.334      P=0.637      P=0.361N     P=0.472     |P=0.044 *    (e)          (e)          P=0.226      |
|POLY 3             |     P=0.308      P=0.557      P=0.464N     P=0.383     |P=0.039 *    (e)          (e)          P=0.225      |
|POLY 1.5           |     P=0.309      P=0.537      P=0.478N     P=0.375     |P=0.040 *    (e)          (e)          P=0.229      |
|POLY 6             |     P=0.307      P=0.585      P=0.441N     P=0.396     |P=0.039 *    (e)          (e)          P=0.221      |
|LOGISTIC REGRESSION|     P=0.311      P=0.552      P=0.405N     P=0.435     |(e)          (e)          (e)          P=0.226      |
|COCH-ARM / FISHERS |     P=0.305      P=0.500      P=0.500N     P=0.357     |P=0.042 *    (e)          (e)          P=0.247      |
|=================================================================================================================================|
       Date:  02/24/00                           EXPERIMENT: 88050 TEST: 05                                            Page 14
                     Statistical Analysis of Primary Tumors in Rats(FISCHER 344)       -                 METHACRYLONITRILE
                                         Terminal Sacrifice at 105 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Skin                                                                                                                             |
|     Fibroma, Fibrosarcoma, Sarcoma, Myxoma, Myxosarcoma,                                                                        |
|     or Fibrous Histiocytoma                                                                                                     |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     3/50 (6%)    5/50 (10%)   3/50 (6%)    8/50 (16%)  |0/50 (0%)    0/50 (0%)    0/50 (0%)    2/50 (4%)    |
|POLY-3 ADJUSTED (b)|     7.3%         11.0%        6.8%         18.2%       |0.0%         0.0%         0.0%         4.5%         |
|TERMINAL (d)       |     2/25 (8%)    3/34 (9%)    3/35 (9%)    5/31 (16%)  |0/38 (0%)    0/33 (0%)    0/34 (0%)    2/36 (6%)    |
|FIRST INCIDENCE    |     701          641          729 (T)      603         |---          ---          ---          731 (T)      |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.085      P=0.508      P=0.511N     P=0.168     |P=0.044 *    (e)          (e)          P=0.226      |
|POLY 3             |     P=0.078      P=0.416      P=0.625N     P=0.121     |P=0.039 *    (e)          (e)          P=0.225      |
|POLY 1.5           |     P=0.076      P=0.394      P=0.640N     P=0.113     |P=0.040 *    (e)          (e)          P=0.229      |
|POLY 6             |     P=0.082      P=0.445      P=0.601N     P=0.135     |P=0.039 *    (e)          (e)          P=0.221      |
|LOGISTIC REGRESSION|     P=0.073      P=0.416      P=0.560N     P=0.115     |(e)          (e)          (e)          P=0.226      |
|COCH-ARM / FISHERS |     P=0.072      P=0.357      P=0.661N     P=0.100     |P=0.042 *    (e)          (e)          P=0.247      |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Skin                                                                                                                             |
|     Fibrosarcoma                                                                                                                |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     0/50 (0%)    0/50 (0%)    1/50 (2%)    2/50 (4%)   |0/50 (0%)    0/50 (0%)    0/50 (0%)    0/50 (0%)    |
|POLY-3 ADJUSTED (b)|     0.0%         0.0%         2.3%         4.6%        |0.0%         0.0%         0.0%         0.0%         |
|TERMINAL (d)       |     0/25 (0%)    0/34 (0%)    1/35 (3%)    0/31 (0%)   |0/38 (0%)    0/33 (0%)    0/34 (0%)    0/36 (0%)    |
|FIRST INCIDENCE    |     ---          ---          729 (T)      603         |---          ---          ---          ---          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.085      (e)          P=0.567      P=0.260     |(e)          (e)          (e)          (e)          |
|POLY 3             |     P=0.086      (e)          P=0.516      P=0.252     |(e)          (e)          (e)          (e)          |
|POLY 1.5           |     P=0.085      (e)          P=0.510      P=0.247     |(e)          (e)          (e)          (e)          |
|POLY 6             |     P=0.089      (e)          P=0.527      P=0.261     |(e)          (e)          (e)          (e)          |
|LOGISTIC REGRESSION|     P=0.083      (e)          P=0.567      P=0.221     |(e)          (e)          (e)          (e)          |
|COCH-ARM / FISHERS |     P=0.084      (e)          P=0.500      P=0.247     |(e)          (e)          (e)          (e)          |
|=================================================================================================================================|
       Date:  02/24/00                           EXPERIMENT: 88050 TEST: 05                                            Page 15
                     Statistical Analysis of Primary Tumors in Rats(FISCHER 344)       -                 METHACRYLONITRILE
                                         Terminal Sacrifice at 105 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Skin                                                                                                                             |
|     Fibrosarcoma, Sarcoma, Myxosarcoma, or Fibrous Histiocytoma                                                                 |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     0/50 (0%)    1/50 (2%)    1/50 (2%)    3/50 (6%)   |0/50 (0%)    0/50 (0%)    0/50 (0%)    0/50 (0%)    |
|POLY-3 ADJUSTED (b)|     0.0%         2.2%         2.3%         6.8%        |0.0%         0.0%         0.0%         0.0%         |
|TERMINAL (d)       |     0/25 (0%)    1/34 (3%)    1/35 (3%)    0/31 (0%)   |0/38 (0%)    0/33 (0%)    0/34 (0%)    0/36 (0%)    |
|FIRST INCIDENCE    |     ---          729 (T)      729 (T)      603         |---          ---          ---          ---          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.067      P=0.561      P=0.567      P=0.140     |(e)          (e)          (e)          (e)          |
|POLY 3             |     P=0.070      P=0.519      P=0.516      P=0.132     |(e)          (e)          (e)          (e)          |
|POLY 1.5           |     P=0.068      P=0.513      P=0.510      P=0.127     |(e)          (e)          (e)          (e)          |
|POLY 6             |     P=0.073      P=0.528      P=0.527      P=0.141     |(e)          (e)          (e)          (e)          |
|LOGISTIC REGRESSION|     P=0.063      P=0.561      P=0.567      P=0.105     |(e)          (e)          (e)          (e)          |
|COCH-ARM / FISHERS |     P=0.064      P=0.500      P=0.500      P=0.121     |(e)          (e)          (e)          (e)          |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Skin                                                                                                                             |
|     Keratoacanthoma                                                                                                             |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     1/50 (2%)    5/50 (10%)   3/50 (6%)    2/50 (4%)   |0/50 (0%)    0/50 (0%)    0/50 (0%)    0/50 (0%)    |
|POLY-3 ADJUSTED (b)|     2.4%         11.0%        6.8%         4.6%        |0.0%         0.0%         0.0%         0.0%         |
|TERMINAL (d)       |     0/25 (0%)    3/34 (9%)    3/35 (9%)    2/31 (7%)   |0/38 (0%)    0/33 (0%)    0/34 (0%)    0/36 (0%)    |
|FIRST INCIDENCE    |     579          674          729 (T)      729 (T)     |---          ---          ---          ---          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.441N     P=0.172      P=0.404      P=0.552     |(e)          (e)          (e)          (e)          |
|POLY 3             |     P=0.450N     P=0.124      P=0.331      P=0.514     |(e)          (e)          (e)          (e)          |
|POLY 1.5           |     P=0.453N     P=0.116      P=0.321      P=0.510     |(e)          (e)          (e)          (e)          |
|POLY 6             |     P=0.443N     P=0.136      P=0.347      P=0.521     |(e)          (e)          (e)          (e)          |
|LOGISTIC REGRESSION|     P=0.461N     P=0.105      P=0.316      P=0.503     |(e)          (e)          (e)          (e)          |
|COCH-ARM / FISHERS |     P=0.466N     P=0.102      P=0.309      P=0.500     |(e)          (e)          (e)          (e)          |
|=================================================================================================================================|
       Date:  02/24/00                           EXPERIMENT: 88050 TEST: 05                                            Page 16
                     Statistical Analysis of Primary Tumors in Rats(FISCHER 344)       -                 METHACRYLONITRILE
                                         Terminal Sacrifice at 105 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Skin                                                                                                                             |
|     Squamous Cell Papilloma, Papilloma, Squamous Cell                                                                           |
|     Carcinoma or Keratoacanthoma                                                                                                |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     2/50 (4%)    5/50 (10%)   3/50 (6%)    2/50 (4%)   |1/50 (2%)    0/50 (0%)    0/50 (0%)    0/50 (0%)    |
|POLY-3 ADJUSTED (b)|     4.8%         11.0%        6.8%         4.6%        |2.1%         0.0%         0.0%         0.0%         |
|TERMINAL (d)       |     0/25 (0%)    3/34 (9%)    3/35 (9%)    2/31 (7%)   |1/38 (3%)    0/33 (0%)    0/34 (0%)    0/36 (0%)    |
|FIRST INCIDENCE    |     579          674          729 (T)      729 (T)     |731 (T)      ---          ---          ---          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.338N     P=0.326      P=0.610      P=0.644N    |P=0.474N     P=0.528N     P=0.522N     P=0.511N     |
|POLY 3             |     P=0.352N     P=0.253      P=0.530      P=0.682N    |P=0.463N     P=0.513N     P=0.516N     P=0.511N     |
|POLY 1.5           |     P=0.353N     P=0.241      P=0.518      P=0.685N    |P=0.467N     P=0.508N     P=0.511N     P=0.507N     |
|POLY 6             |     P=0.350N     P=0.270      P=0.548      P=0.677N    |P=0.459N     P=0.519N     P=0.520N     P=0.515N     |
|LOGISTIC REGRESSION|     P=0.356N     P=0.218      P=0.511      P=0.694N    |P=0.474N     (e)          (e)          (e)          |
|COCH-ARM / FISHERS |     P=0.361N     P=0.218      P=0.500      P=0.691N    |P=0.474N     P=0.500N     P=0.500N     P=0.500N     |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Skin                                                                                                                             |
|     Squamous Cell Papilloma, Papilloma, or Keratoacanthoma                                                                      |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     1/50 (2%)    5/50 (10%)   3/50 (6%)    2/50 (4%)   |1/50 (2%)    0/50 (0%)    0/50 (0%)    0/50 (0%)    |
|POLY-3 ADJUSTED (b)|     2.4%         11.0%        6.8%         4.6%        |2.1%         0.0%         0.0%         0.0%         |
|TERMINAL (d)       |     0/25 (0%)    3/34 (9%)    3/35 (9%)    2/31 (7%)   |1/38 (3%)    0/33 (0%)    0/34 (0%)    0/36 (0%)    |
|FIRST INCIDENCE    |     579          674          729 (T)      729 (T)     |731 (T)      ---          ---          ---          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.441N     P=0.172      P=0.404      P=0.552     |P=0.474N     P=0.528N     P=0.522N     P=0.511N     |
|POLY 3             |     P=0.450N     P=0.124      P=0.331      P=0.514     |P=0.463N     P=0.513N     P=0.516N     P=0.511N     |
|POLY 1.5           |     P=0.453N     P=0.116      P=0.321      P=0.510     |P=0.467N     P=0.508N     P=0.511N     P=0.507N     |
|POLY 6             |     P=0.443N     P=0.136      P=0.347      P=0.521     |P=0.459N     P=0.519N     P=0.520N     P=0.515N     |
|LOGISTIC REGRESSION|     P=0.461N     P=0.105      P=0.316      P=0.503     |P=0.474N     (e)          (e)          (e)          |
|COCH-ARM / FISHERS |     P=0.466N     P=0.102      P=0.309      P=0.500     |P=0.474N     P=0.500N     P=0.500N     P=0.500N     |
|=================================================================================================================================|
       Date:  02/24/00                           EXPERIMENT: 88050 TEST: 05                                            Page 17
                     Statistical Analysis of Primary Tumors in Rats(FISCHER 344)       -                 METHACRYLONITRILE
                                         Terminal Sacrifice at 105 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Testes                                                                                                                           |
|     Adenoma                                                                                                                     |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     40/50 (80%)  45/50 (90%)  47/50 (94%)  46/50 (92%) |                                                    |
|POLY-3 ADJUSTED (b)|     89.1%        92.6%        98.7%        95.8%       |                                                    |
|TERMINAL (d)       |     25/25 (100%) 32/34 (94%)  35/35 (100%) 30/31 (97%) |                                                    |
|FIRST INCIDENCE    |     439          474          464          456         |                                                    |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.418      P=0.179N     P=0.202N     P=0.468N    |                                                    |
|POLY 3             |     P=0.152      P=0.394      P=0.024 *    P=0.155     |                                                    |
|POLY 1.5           |     P=0.132      P=0.271      P=0.026 *    P=0.113     |                                                    |
|POLY 6             |     P=0.230      P=0.623      P=0.046 *    P=0.304     |                                                    |
|LOGISTIC REGRESSION|     P=0.086      P=0.359      P=0.039 *    P=0.094     |                                                    |
|COCH-ARM / FISHERS |     P=0.117      P=0.131      P=0.036 *    P=0.074     |                                                    |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Thyroid Gland: C-Cell                                                                                                            |
|     Adenoma                                                                                                                     |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     9/50 (18%)   12/50 (24%)  8/50 (16%)   6/50 (12%)  |3/50 (6%)    8/50 (16%)   5/50 (10%)   8/50 (16%)   |
|POLY-3 ADJUSTED (b)|     21.6%        26.4%        17.6%        13.6%       |6.4%         18.1%        11.6%        17.7%        |
|TERMINAL (d)       |     6/25 (24%)   9/34 (27%)   5/35 (14%)   4/31 (13%)  |3/38 (8%)    7/33 (21%)   5/34 (15%)   5/36 (14%)   |
|FIRST INCIDENCE    |     579          674          464          456         |731 (T)      505          731 (T)      527          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.109N     P=0.577      P=0.278N     P=0.185N    |P=0.199      P=0.065      P=0.295      P=0.088      |
|POLY 3             |     P=0.116N     P=0.391      P=0.420N     P=0.247N    |P=0.184      P=0.083      P=0.313      P=0.089      |
|POLY 1.5           |     P=0.120N     P=0.364      P=0.451N     P=0.259N    |P=0.187      P=0.089      P=0.326      P=0.092      |
|POLY 6             |     P=0.112N     P=0.428      P=0.375N     P=0.230N    |P=0.184      P=0.076      P=0.302      P=0.088      |
|LOGISTIC REGRESSION|     P=0.127N     P=0.432      P=0.467N     P=0.267N    |P=0.186      P=0.086      P=0.295      P=0.101      |
|COCH-ARM / FISHERS |     P=0.132N     P=0.312      P=0.500N     P=0.288N    |P=0.196      P=0.100      P=0.357      P=0.100      |
|=================================================================================================================================|
       Date:  02/24/00                           EXPERIMENT: 88050 TEST: 05                                            Page 18
                     Statistical Analysis of Primary Tumors in Rats(FISCHER 344)       -                 METHACRYLONITRILE
                                         Terminal Sacrifice at 105 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Thyroid Gland: C-Cell                                                                                                            |
|     Carcinoma                                                                                                                   |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     1/50 (2%)    1/50 (2%)    1/50 (2%)    0/50 (0%)   |2/50 (4%)    1/50 (2%)    1/50 (2%)    0/50 (0%)    |
|POLY-3 ADJUSTED (b)|     2.4%         2.2%         2.3%         0.0%        |4.3%         2.3%         2.3%         0.0%         |
|TERMINAL (d)       |     0/25 (0%)    1/34 (3%)    1/35 (3%)    0/31 (0%)   |2/38 (5%)    1/33 (3%)    0/34 (0%)    0/36 (0%)    |
|FIRST INCIDENCE    |     697          729 (T)      729 (T)      ---         |731 (T)      731 (T)      724          ---          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.308N     P=0.703N     P=0.703N     P=0.477N    |P=0.196N     P=0.549N     P=0.538N     P=0.250N     |
|POLY 3             |     P=0.323N     P=0.739N     P=0.743N     P=0.490N    |P=0.196N     P=0.523N     P=0.528N     P=0.250N     |
|POLY 1.5           |     P=0.322N     P=0.747N     P=0.750N     P=0.493N    |P=0.196N     P=0.514N     P=0.520N     P=0.246N     |
|POLY 6             |     P=0.322N     P=0.730N     P=0.731N     P=0.485N    |P=0.197N     P=0.533N     P=0.534N     P=0.254N     |
|LOGISTIC REGRESSION|     P=0.316N     P=0.735N     P=0.738N     P=0.492N    |P=0.200N     P=0.549N     P=0.542N     (e)          |
|COCH-ARM / FISHERS |     P=0.323N     P=0.753N     P=0.753N     P=0.500N    |P=0.194N     P=0.500N     P=0.500N     P=0.247N     |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Thyroid Gland: C-Cell                                                                                                            |
|     Carcinoma or Adenoma                                                                                                        |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     10/50 (20%)  13/50 (26%)  9/50 (18%)   6/50 (12%)  |5/50 (10%)   9/50 (18%)   6/50 (12%)   8/50 (16%)   |
|POLY-3 ADJUSTED (b)|     23.9%        28.6%        19.8%        13.6%       |10.7%        20.3%        13.9%        17.7%        |
|TERMINAL (d)       |     6/25 (24%)   10/34 (29%)  6/35 (17%)   4/31 (13%)  |5/38 (13%)   8/33 (24%)   5/34 (15%)   5/36 (14%)   |
|FIRST INCIDENCE    |     579          674          464          456         |731 (T)      505          724          527          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.068N     P=0.587N     P=0.267N     P=0.126N    |P=0.392      P=0.126      P=0.422      P=0.244      |
|POLY 3             |     P=0.072N     P=0.399      P=0.417N     P=0.171N    |P=0.377      P=0.164      P=0.444      P=0.257      |
|POLY 1.5           |     P=0.075N     P=0.372      P=0.449N     P=0.182N    |P=0.379      P=0.175      P=0.461      P=0.262      |
|POLY 6             |     P=0.069N     P=0.435      P=0.372N     P=0.158N    |P=0.379      P=0.152      P=0.431      P=0.254      |
|LOGISTIC REGRESSION|     P=0.080N     P=0.447      P=0.459N     P=0.188N    |P=0.372      P=0.159      P=0.407      P=0.270      |
|COCH-ARM / FISHERS |     P=0.084N     P=0.318      P=0.500N     P=0.207N    |P=0.390      P=0.194      P=0.500      P=0.277      |
|=================================================================================================================================|
       Date:  02/24/00                           EXPERIMENT: 88050 TEST: 05                                            Page 19
                     Statistical Analysis of Primary Tumors in Rats(FISCHER 344)       -                 METHACRYLONITRILE
                                         Terminal Sacrifice at 105 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Thyroid Gland: Follicular Cell                                                                                                   |
|     Adenoma                                                                                                                     |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     1/50 (2%)    0/50 (0%)    2/50 (4%)    0/50 (0%)   |0/50 (0%)    0/50 (0%)    0/50 (0%)    0/50 (0%)    |
|POLY-3 ADJUSTED (b)|     2.4%         0.0%         4.5%         0.0%        |0.0%         0.0%         0.0%         0.0%         |
|TERMINAL (d)       |     0/25 (0%)    0/34 (0%)    2/35 (6%)    0/31 (0%)   |0/38 (0%)    0/33 (0%)    0/34 (0%)    0/36 (0%)    |
|FIRST INCIDENCE    |     629          ---          729 (T)      ---         |---          ---          ---          ---          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.444N     P=0.471N     P=0.591      P=0.490N    |(e)          (e)          (e)          (e)          |
|POLY 3             |     P=0.462N     P=0.482N     P=0.526      P=0.491N    |(e)          (e)          (e)          (e)          |
|POLY 1.5           |     P=0.459N     P=0.488N     P=0.516      P=0.494N    |(e)          (e)          (e)          (e)          |
|POLY 6             |     P=0.465N     P=0.475N     P=0.542      P=0.487N    |(e)          (e)          (e)          (e)          |
|LOGISTIC REGRESSION|     P=0.454N     P=0.535N     P=0.516      P=0.518N    |(e)          (e)          (e)          (e)          |
|COCH-ARM / FISHERS |     P=0.455N     P=0.500N     P=0.500      P=0.500N    |(e)          (e)          (e)          (e)          |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Thyroid Gland: Follicular Cell                                                                                                   |
|     Carcinoma                                                                                                                   |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     0/50 (0%)    1/50 (2%)    1/50 (2%)    2/50 (4%)   |1/50 (2%)    0/50 (0%)    0/50 (0%)    0/50 (0%)    |
|POLY-3 ADJUSTED (b)|     0.0%         2.2%         2.2%         4.6%        |2.1%         0.0%         0.0%         0.0%         |
|TERMINAL (d)       |     0/25 (0%)    0/34 (0%)    0/35 (0%)    2/31 (7%)   |1/38 (3%)    0/33 (0%)    0/34 (0%)    0/36 (0%)    |
|FIRST INCIDENCE    |     ---          696          642          729 (T)     |731 (T)      ---          ---          ---          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.201      P=0.545      P=0.535      P=0.286     |P=0.474N     P=0.528N     P=0.522N     P=0.511N     |
|POLY 3             |     P=0.201      P=0.520      P=0.518      P=0.249     |P=0.463N     P=0.513N     P=0.516N     P=0.511N     |
|POLY 1.5           |     P=0.199      P=0.513      P=0.511      P=0.245     |P=0.467N     P=0.508N     P=0.511N     P=0.507N     |
|POLY 6             |     P=0.204      P=0.529      P=0.529      P=0.255     |P=0.459N     P=0.519N     P=0.520N     P=0.515N     |
|LOGISTIC REGRESSION|     P=0.194      P=0.511      P=0.486      P=0.286     |P=0.474N     (e)          (e)          (e)          |
|COCH-ARM / FISHERS |     P=0.194      P=0.500      P=0.500      P=0.247     |P=0.474N     P=0.500N     P=0.500N     P=0.500N     |
|=================================================================================================================================|
       Date:  02/24/00                           EXPERIMENT: 88050 TEST: 05                                            Page 20
                     Statistical Analysis of Primary Tumors in Rats(FISCHER 344)       -                 METHACRYLONITRILE
                                         Terminal Sacrifice at 105 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Thyroid Gland: Follicular Cell                                                                                                   |
|     Carcinoma or Adenoma                                                                                                        |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |                                                        |                                                    |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     1/50 (2%)    1/50 (2%)    3/50 (6%)    2/50 (4%)   |1/50 (2%)    0/50 (0%)    0/50 (0%)    0/50 (0%)    |
|POLY-3 ADJUSTED (b)|     2.4%         2.2%         6.7%         4.6%        |2.1%         0.0%         0.0%         0.0%         |
|TERMINAL (d)       |     0/25 (0%)    0/34 (0%)    2/35 (6%)    2/31 (7%)   |1/38 (3%)    0/33 (0%)    0/34 (0%)    0/36 (0%)    |
|FIRST INCIDENCE    |     629          696          642          729 (T)     |731 (T)      ---          ---          ---          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.416      P=0.719N     P=0.396      P=0.555     |P=0.474N     P=0.528N     P=0.522N     P=0.511N     |
|POLY 3             |     P=0.401      P=0.740N     P=0.335      P=0.515     |P=0.463N     P=0.513N     P=0.516N     P=0.511N     |
|POLY 1.5           |     P=0.402      P=0.747N     P=0.323      P=0.511     |P=0.467N     P=0.508N     P=0.511N     P=0.507N     |
|POLY 6             |     P=0.401      P=0.731N     P=0.354      P=0.522     |P=0.459N     P=0.519N     P=0.520N     P=0.515N     |
|LOGISTIC REGRESSION|     P=0.401      P=0.753      P=0.308      P=0.513     |P=0.474N     (e)          (e)          (e)          |
|COCH-ARM / FISHERS |     P=0.399      P=0.753N     P=0.309      P=0.500     |P=0.474N     P=0.500N     P=0.500N     P=0.500N     |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Uterus                                                                                                                           |
|     Polyp Stromal                                                                                                               |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |                                                        |7/50 (14%)   8/50 (16%)   9/50 (18%)   11/50 (22%)  |
|POLY-3 ADJUSTED (b)|                                                        |14.9%        18.3%        20.6%        24.8%        |
|TERMINAL (d)       |                                                        |5/38 (13%)   8/33 (24%)   8/34 (24%)   8/36 (22%)   |
|FIRST INCIDENCE    |                                                        |616          731 (T)      470          693          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |                                                        |P=0.185      P=0.384      P=0.307      P=0.188      |
|POLY 3             |                                                        |P=0.155      P=0.437      P=0.332      P=0.176      |
|POLY 1.5           |                                                        |P=0.163      P=0.461      P=0.350      P=0.190      |
|POLY 6             |                                                        |P=0.149      P=0.409      P=0.316      P=0.164      |
|LOGISTIC REGRESSION|                                                        |P=0.157      P=0.417      P=0.353      P=0.172      |
|COCH-ARM / FISHERS |                                                        |P=0.179      P=0.500      P=0.393      P=0.218      |
|=================================================================================================================================|
       Date:  02/24/00                           EXPERIMENT: 88050 TEST: 05                                            Page 21
                     Statistical Analysis of Primary Tumors in Rats(FISCHER 344)       -                 METHACRYLONITRILE
                                         Terminal Sacrifice at 105 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Uterus                                                                                                                           |
|     Sarcoma Stromal                                                                                                             |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |                                                        |0/50 (0%)    1/50 (2%)    1/50 (2%)    2/50 (4%)    |
|POLY-3 ADJUSTED (b)|                                                        |0.0%         2.3%         2.3%         4.4%         |
|TERMINAL (d)       |                                                        |0/38 (0%)    0/33 (0%)    0/34 (0%)    0/36 (0%)    |
|FIRST INCIDENCE    |                                                        |---          441          711          549          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |                                                        |P=0.190      P=0.500      P=0.469      P=0.225      |
|POLY 3             |                                                        |P=0.188      P=0.490      P=0.484      P=0.229      |
|POLY 1.5           |                                                        |P=0.190      P=0.494      P=0.489      P=0.232      |
|POLY 6             |                                                        |P=0.188      P=0.486      P=0.481      P=0.228      |
|LOGISTIC REGRESSION|                                                        |P=0.225      P=0.758      P=0.488      P=0.313      |
|COCH-ARM / FISHERS |                                                        |P=0.194      P=0.500      P=0.500      P=0.247      |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Uterus                                                                                                                           |
|     Sarcoma Stromal or Polyp Stromal                                                                                            |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |                                                        |7/50 (14%)   9/50 (18%)   10/50 (20%)  13/50 (26%)  |
|POLY-3 ADJUSTED (b)|                                                        |14.9%        20.3%        22.8%        28.7%        |
|TERMINAL (d)       |                                                        |5/38 (13%)   8/33 (24%)   8/34 (24%)   8/36 (22%)   |
|FIRST INCIDENCE    |                                                        |616          441          470          549          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |                                                        |P=0.098      P=0.289      P=0.222      P=0.093      |
|POLY 3             |                                                        |P=0.079      P=0.345      P=0.242      P=0.085      |
|POLY 1.5           |                                                        |P=0.082      P=0.364      P=0.258      P=0.091      |
|POLY 6             |                                                        |P=0.079      P=0.321      P=0.229      P=0.081      |
|LOGISTIC REGRESSION|                                                        |P=0.083      P=0.372      P=0.260      P=0.092      |
|COCH-ARM / FISHERS |                                                        |P=0.090      P=0.393      P=0.298      P=0.105      |
|=================================================================================================================================|
       Date:  02/24/00                           EXPERIMENT: 88050 TEST: 05                                            Page 22
                     Statistical Analysis of Primary Tumors in Rats(FISCHER 344)       -                 METHACRYLONITRILE
                                         Terminal Sacrifice at 105 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|Zymbal's Gland                                                                                                                   |
|     Carcinoma or Adenoma                                                                                                        |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     0/50 (0%)    2/50 (4%)    0/50 (0%)    1/50 (2%)   |0/50 (0%)    0/50 (0%)    1/50 (2%)    0/50 (0%)    |
|POLY-3 ADJUSTED (b)|     0.0%         4.4%         0.0%         2.3%        |0.0%         0.0%         2.3%         0.0%         |
|TERMINAL (d)       |     0/25 (0%)    1/34 (3%)    0/35 (0%)    1/31 (3%)   |0/38 (0%)    0/33 (0%)    1/34 (3%)    0/36 (0%)    |
|FIRST INCIDENCE    |     ---          697          ---          729 (T)     |---          ---          731 (T)      ---          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.638      P=0.297      (e)          P=0.543     |P=0.782N     (e)          P=0.478      (e)          |
|POLY 3             |     P=0.641      P=0.260      (e)          P=0.510     |P=0.790N     (e)          P=0.484      (e)          |
|POLY 1.5           |     P=0.635      P=0.252      (e)          P=0.507     |P=0.789N     (e)          P=0.489      (e)          |
|POLY 6             |     P=0.649      P=0.271      (e)          P=0.516     |P=0.791N     (e)          P=0.480      (e)          |
|LOGISTIC REGRESSION|     P=0.628      P=0.265      (e)          P=0.543     |(e)          (e)          P=0.478      (e)          |
|COCH-ARM / FISHERS |     P=0.622      P=0.247      (e)          P=0.500     |P=0.786N     (e)          P=0.500      (e)          |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|All Organs                                                                                                                       |
|     Hemangiosarcoma                                                                                                             |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     0/50 (0%)    2/50 (4%)    1/50 (2%)    1/50 (2%)   |1/50 (2%)    0/50 (0%)    0/50 (0%)    0/50 (0%)    |
|POLY-3 ADJUSTED (b)|     0.0%         4.4%         2.3%         2.3%        |2.1%         0.0%         0.0%         0.0%         |
|TERMINAL (d)       |     0/25 (0%)    2/34 (6%)    1/35 (3%)    1/31 (3%)   |1/38 (3%)    0/33 (0%)    0/34 (0%)    0/36 (0%)    |
|FIRST INCIDENCE    |     ---          729 (T)      729 (T)      729 (T)     |731 (T)      ---          ---          ---          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.642      P=0.308      P=0.567      P=0.543     |P=0.474N     P=0.528N     P=0.522N     P=0.511N     |
|POLY 3             |     P=0.636      P=0.259      P=0.516      P=0.510     |P=0.463N     P=0.513N     P=0.516N     P=0.511N     |
|POLY 1.5           |     P=0.631      P=0.252      P=0.510      P=0.507     |P=0.467N     P=0.508N     P=0.511N     P=0.507N     |
|POLY 6             |     P=0.645      P=0.270      P=0.527      P=0.516     |P=0.459N     P=0.519N     P=0.520N     P=0.515N     |
|LOGISTIC REGRESSION|     (e)          P=0.308      P=0.567      P=0.543     |P=0.474N     (e)          (e)          (e)          |
|COCH-ARM / FISHERS |     P=0.619      P=0.247      P=0.500      P=0.500     |P=0.474N     P=0.500N     P=0.500N     P=0.500N     |
|=================================================================================================================================|
       Date:  02/24/00                           EXPERIMENT: 88050 TEST: 05                                            Page 23
                     Statistical Analysis of Primary Tumors in Rats(FISCHER 344)       -                 METHACRYLONITRILE
                                         Terminal Sacrifice at 105 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|All Organs                                                                                                                       |
|     Leukemia: Lymphocytic, Monocytic, Mononuclear, or                                                                           |
|     Undifferentiated                                                                                                            |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     20/50 (40%)  20/50 (40%)  14/50 (28%)  12/50 (24%) |21/50 (42%)  19/50 (38%)  16/50 (32%)  19/50 (38%)  |
|POLY-3 ADJUSTED (b)|     46.4%        42.9%        30.9%        26.9%       |42.2%        40.3%        35.5%        41.2%        |
|TERMINAL (d)       |     9/25 (36%)   13/34 (38%)  7/35 (20%)   7/31 (23%)  |12/38 (32%)  9/33 (27%)   8/34 (24%)   12/36 (33%)  |
|FIRST INCIDENCE    |     584          589          642          351         |438          527          562          500          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.036N*    P=0.238N     P=0.039N*    P=0.033N*   |P=0.481N     P=0.545      P=0.361N     P=0.516N     |
|POLY 3             |     P=0.030N*    P=0.450N     P=0.096N     P=0.043N*   |P=0.539N     P=0.505N     P=0.323N     P=0.540N     |
|POLY 1.5           |     P=0.030N*    P=0.492N     P=0.112N     P=0.047N*   |P=0.508N     P=0.477N     P=0.285N     P=0.499N     |
|POLY 6             |     P=0.033N*    P=0.401N     P=0.077N     P=0.040N*   |P=0.526      P=0.529N     P=0.348N     P=0.582N     |
|LOGISTIC REGRESSION|     P=0.033N*    P=0.448N     P=0.090N     P=0.052N    |P=0.442N     P=0.298N     P=0.173N     P=0.366N     |
|COCH-ARM / FISHERS |     P=0.036N*    P=0.581N     P=0.146N     P=0.066N    |P=0.454N     P=0.419N     P=0.204N     P=0.419N     |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|All Organs                                                                                                                       |
|     Mesothelioma: Benign, Malignant, NOS                                                                                        |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     0/50 (0%)    0/50 (0%)    2/50 (4%)    2/50 (4%)   |0/50 (0%)    0/50 (0%)    0/50 (0%)    0/50 (0%)    |
|POLY-3 ADJUSTED (b)|     0.0%         0.0%         4.5%         4.6%        |0.0%         0.0%         0.0%         0.0%         |
|TERMINAL (d)       |     0/25 (0%)    0/34 (0%)    2/35 (6%)    2/31 (7%)   |0/38 (0%)    0/33 (0%)    0/34 (0%)    0/36 (0%)    |
|FIRST INCIDENCE    |     ---          ---          729 (T)      729 (T)     |---          ---          ---          ---          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.128      (e)          P=0.315      P=0.286     |(e)          (e)          (e)          (e)          |
|POLY 3             |     P=0.123      (e)          P=0.256      P=0.249     |(e)          (e)          (e)          (e)          |
|POLY 1.5           |     P=0.123      (e)          P=0.248      P=0.245     |(e)          (e)          (e)          (e)          |
|POLY 6             |     P=0.124      (e)          P=0.268      P=0.255     |(e)          (e)          (e)          (e)          |
|LOGISTIC REGRESSION|     (e)          (e)          P=0.315      P=0.286     |(e)          (e)          (e)          (e)          |
|COCH-ARM / FISHERS |     P=0.122      (e)          P=0.247      P=0.247     |(e)          (e)          (e)          (e)          |
|=================================================================================================================================|
       Date:  02/24/00                           EXPERIMENT: 88050 TEST: 05                                            Page 24
                     Statistical Analysis of Primary Tumors in Rats(FISCHER 344)       -                 METHACRYLONITRILE
                                         Terminal Sacrifice at 105 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|All Organs                                                                                                                       |
|     Mesothelioma: Malignant                                                                                                     |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     0/50 (0%)    0/50 (0%)    2/50 (4%)    2/50 (4%)   |0/50 (0%)    0/50 (0%)    0/50 (0%)    0/50 (0%)    |
|POLY-3 ADJUSTED (b)|     0.0%         0.0%         4.5%         4.6%        |0.0%         0.0%         0.0%         0.0%         |
|TERMINAL (d)       |     0/25 (0%)    0/34 (0%)    2/35 (6%)    2/31 (7%)   |0/38 (0%)    0/33 (0%)    0/34 (0%)    0/36 (0%)    |
|FIRST INCIDENCE    |     ---          ---          729 (T)      729 (T)     |---          ---          ---          ---          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.128      (e)          P=0.315      P=0.286     |(e)          (e)          (e)          (e)          |
|POLY 3             |     P=0.123      (e)          P=0.256      P=0.249     |(e)          (e)          (e)          (e)          |
|POLY 1.5           |     P=0.123      (e)          P=0.248      P=0.245     |(e)          (e)          (e)          (e)          |
|POLY 6             |     P=0.124      (e)          P=0.268      P=0.255     |(e)          (e)          (e)          (e)          |
|LOGISTIC REGRESSION|     (e)          (e)          P=0.315      P=0.286     |(e)          (e)          (e)          (e)          |
|COCH-ARM / FISHERS |     P=0.122      (e)          P=0.247      P=0.247     |(e)          (e)          (e)          (e)          |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|All Organs                                                                                                                       |
|     Osteosarcoma or Osteoma                                                                                                     |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     1/50 (2%)    2/50 (4%)    0/50 (0%)    0/50 (0%)   |0/50 (0%)    0/50 (0%)    0/50 (0%)    0/50 (0%)    |
|POLY-3 ADJUSTED (b)|     2.4%         4.4%         0.0%         0.0%        |0.0%         0.0%         0.0%         0.0%         |
|TERMINAL (d)       |     0/25 (0%)    1/34 (3%)    0/35 (0%)    0/31 (0%)   |0/38 (0%)    0/33 (0%)    0/34 (0%)    0/36 (0%)    |
|FIRST INCIDENCE    |     474          716          ---          ---         |---          ---          ---          ---          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.201N     P=0.566      P=0.500N     P=0.500N    |(e)          (e)          (e)          (e)          |
|POLY 3             |     P=0.205N     P=0.528      P=0.487N     P=0.493N    |(e)          (e)          (e)          (e)          |
|POLY 1.5           |     P=0.206N     P=0.519      P=0.492N     P=0.495N    |(e)          (e)          (e)          (e)          |
|POLY 6             |     P=0.202N     P=0.541      P=0.478N     P=0.489N    |(e)          (e)          (e)          (e)          |
|LOGISTIC REGRESSION|     P=0.218N     P=0.451      P=0.591N     P=0.605N    |(e)          (e)          (e)          (e)          |
|COCH-ARM / FISHERS |     P=0.209N     P=0.500      P=0.500N     P=0.500N    |(e)          (e)          (e)          (e)          |
|=================================================================================================================================|
       Date:  02/24/00                           EXPERIMENT: 88050 TEST: 05                                            Page 25
                     Statistical Analysis of Primary Tumors in Rats(FISCHER 344)       -                 METHACRYLONITRILE
                                         Terminal Sacrifice at 105 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|All Organs                                                                                                                       |
|     Benign Tumors                                                                                                               |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     47/50 (94%)  49/50 (98%)  49/50 (98%)  47/50 (94%) |35/50 (70%)  38/50 (76%)  34/50 (68%)  37/50 (74%)  |
|POLY-3 ADJUSTED (b)|     97.8%        99.7%        99.9%        97.2%       |73.2%        80.4%        76.3%        78.0%        |
|TERMINAL (d)       |     25/25 (100%) 34/34 (100%) 35/35 (100%) 30/31 (97%) |29/38 (76%)  28/33 (85%)  28/34 (82%)  28/36 (78%)  |
|FIRST INCIDENCE    |     439          474          464          456         |589          441          470          499          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.298N     P=0.072N     P=0.053N     P=0.146N    |P=0.467      P=0.098      P=0.355      P=0.285      |
|POLY 3             |     P=0.405N     P=0.540      P=0.489      P=0.700N    |P=0.461      P=0.271      P=0.457      P=0.378      |
|POLY 1.5           |     P=0.357N     P=0.487      P=0.423      P=0.648N    |P=0.452      P=0.289      P=0.525      P=0.380      |
|POLY 6             |     P=0.409N     P=0.692      P=0.679      P=0.701N    |P=0.481      P=0.251      P=0.403      P=0.384      |
|LOGISTIC REGRESSION|     P=0.352N     P=0.627      P=0.373      P=0.530N    |P=0.383      P=0.203      P=0.403      P=0.292      |
|COCH-ARM / FISHERS |     P=0.414N     P=0.309      P=0.309      P=0.661N    |P=0.468      P=0.326      P=0.500N     P=0.412      |
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|All Organs                                                                                                                       |
|     Malignant Tumors                                                                                                            |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     29/50 (58%)  30/50 (60%)  24/50 (48%)  26/50 (52%) |26/50 (52%)  21/50 (42%)  21/50 (42%)  24/50 (48%)  |
|POLY-3 ADJUSTED (b)|     62.4%        62.0%        51.9%        54.7%       |52.3%        43.8%        45.7%        49.3%        |
|TERMINAL (d)       |     11/25 (44%)  18/34 (53%)  15/35 (43%)  14/31 (45%) |17/38 (45%)  10/33 (30%)  10/34 (29%)  13/36 (36%)  |
|FIRST INCIDENCE    |     474          400          464          351         |438          441          434          246          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.239N     P=0.235N     P=0.050N     P=0.182N    |P=0.503      P=0.420N     P=0.405N     P=0.530N     |
|POLY 3             |     P=0.243N     P=0.569N     P=0.206N     P=0.291N    |P=0.526      P=0.263N     P=0.330N     P=0.462N     |
|POLY 1.5           |     P=0.239N     P=0.582      P=0.200N     P=0.292N    |P=0.531      P=0.246N     P=0.294N     P=0.446N     |
|POLY 6             |     P=0.254N     P=0.558N     P=0.208N     P=0.298N    |P=0.517      P=0.279N     P=0.350N     P=0.479N     |
|LOGISTIC REGRESSION|     P=0.263N     P=0.516      P=0.177N     P=0.352N    |P=0.530N     P=0.120N     P=0.185N     P=0.280N     |
|COCH-ARM / FISHERS |     P=0.265N     P=0.500      P=0.212N     P=0.344N    |P=0.529      P=0.212N     P=0.212N     P=0.421N     |
|=================================================================================================================================|
       Date:  02/24/00                           EXPERIMENT: 88050 TEST: 05                                            Page 26
                     Statistical Analysis of Primary Tumors in Rats(FISCHER 344)       -                 METHACRYLONITRILE
                                         Terminal Sacrifice at 105 weeks 
|=================================================================================================================================|
|                   |                                                        |                                                    |
|                   |                              Males                     |                       Females                      |
|Dose               |     0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG    |0 MG/KG      3 MG/KG      10 MG/KG     30 MG/KG     |
|                   |                                                        |                                                    |
|=================================================================================================================================|
|                                                                                                                                 |
|All Organs                                                                                                                       |
|     Malignant and Benign Tumors                                                                                                 |
|                                                                                                                                 |
|                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------|
|TUMOR RATES        |     #            #            #            #           |#            #            #            #            |
|-----------        |                                                        |                                                    |
|OVERALL (a)        |     49/50 (98%)  50/50 (100%) 49/50 (98%)  49/50 (98%) |45/50 (90%)  45/50 (90%)  42/50 (84%)  46/50 (92%)  |
|POLY-3 ADJUSTED (b)|     100.0%       100.0%       99.9%        98.0%       |90.0%        92.0%        89.9%        92.0%        |
|TERMINAL (d)       |     25/25 (100%) 34/34 (100%) 35/35 (100%) 30/31 (97%) |33/38 (87%)  30/33 (91%)  30/34 (88%)  32/36 (89%)  |
|FIRST INCIDENCE    |     439          400          464          351         |438          441          434          246          |
|-------------------|                                                        |                                                    |
|STATISTICAL TESTS  |                                                        |                                                    |
|-------------------|                                                        |                                                    |
|LIFE TABLE         |     P=0.338N     P=0.056N     P=0.028N*    P=0.156N    |P=0.434      P=0.211      P=0.448      P=0.328      |
|POLY 3             |     P=0.218N     P=1.000      P=1.000N     P=0.504N    |P=0.487      P=0.499      P=0.626N     P=0.500      |
|POLY 1.5           |     P=0.231N     P=1.000      P=1.000N     P=0.509N    |P=0.464      P=0.537      P=0.519N     P=0.500      |
|POLY 6             |     P=0.216N     P=1.000      P=1.000N     P=0.504N    |P=0.505      P=0.467      P=0.576      P=0.500      |
|LOGISTIC REGRESSION|     P=0.373N     (e)          (e)          P=0.612N    |P=0.363      P=0.598      P=0.472N     (e)          |
|COCH-ARM / FISHERS |     P=0.545N     P=0.500      P=0.753N     P=0.753N    |P=0.412      P=0.630N     P=0.277N     P=0.500      |
|=================================================================================================================================|

(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).