                                                 Toxicology Data Management System                                     Page: 1
 Version: 12/20/00                       Tumor Incidence for Selected Control Animal Groups

 Contract/Lab: All Laboratories                          Route: VARIOUS                                   Date of
 Species: MICE                                           Vehicle: NTP 2000 DIET                           Input File: 20-DEC-2000
 Strain: B6C3F1
 Length of Study: CHRONIC                   

                                                         Study Summary

 ________________________________________________________________________________________________________________________________
|                                                                                                                                |
|                                       Length     Number       Number      Maximum                                              |
|                               Study     of     of Animals    Surviving     Mean                                                |
|Laboratory          Study      Start   Study    Total and     and (Mean  Weekly Body                                            |
|Name                Number     Date   in Days    (#/Cage)     Life Span)   Weight             Chemical                          |
|________________________________________________________________________________________________________________________________|
|                                                                                                                                |
|                                                        MALE                                                                    |
|________________________________________________________________________________________________________________________________|
|                                                                                                                                |
|BATTELLE COLUMBUS  055021503  03/04/97   730       50(1)      38  (707)     53.4     ACRYLONITRILE                              |
|BATTELLE COLUMBUS  055634804  06/19/96   727      100(1)      91  (707)     49.6     CITRAL                                     |
|BATTELLE COLUMBUS  058805006  10/16/95   729       49(1)      35  (704)     50.6     METHACRYLONITRILE                          |
|BATTELLE COLUMBUS  058812004  01/04/96   733       50(1)      40  (705)     46.9     P,P'-DICHLORODIPHENYL SULFONE              |
|BATTELLE COLUMBUS  058800706  08/02/95   727       50(1)      39  (708)     51.4     SODIUM NITRITE                             |
|BATTELLE NORTHWEST 058812404  01/25/96   733       50( )      37  (711)     51.6     INDIUM PHOSPHIDE                           |
|BATTELLE NORTHWEST 056142708  01/13/97   729       50( )      39  (710)     55.4     VANADIUM PENTOXIDE                         |
|I. I. T. RESEARCH I058902906  10/05/94   734      100(1)      76  (711)     53.4     MAGNETIC FIELDS (EMF)                      |
|SOUTHERN RESEARCH  050520309  02/20/96   729       60(1)      52  (712)     48.0     O-NITROTOLUENE                             |
|SOUTHERN RESEARCH  050520508  11/14/95   729       50(1)      46  (722)     47.4     P-NITROTOLUENE                             |
|SOUTHERN RESEARCH  050516106  03/20/96   729       50(1)      39  (696)     51.4     RIDDELLIINE                                |
|________________________________________________________________________________________________________________________________|
|                                                                                                                                |
|                                                       FEMALE                                                                   |
|________________________________________________________________________________________________________________________________|
|                                                                                                                                |
|BATTELLE COLUMBUS  055021503  03/04/97   729       50(5)      39  (709)     62.7     ACRYLONITRILE                              |
|BATTELLE COLUMBUS  055634804  06/19/96   733       99(5)      81  (695)     48.0     CITRAL                                     |
|BATTELLE COLUMBUS  058805006  10/16/95   731       50(5)      35  (700)     58.1     METHACRYLONITRILE                          |
|BATTELLE COLUMBUS  058812004  01/04/96   734       50(5)      42  (717)     46.5     P,P'-DICHLORODIPHENYL SULFONE              |
|BATTELLE COLUMBUS  058800706  08/02/95   728       50(5)      40  (702)     58.8     SODIUM NITRITE                             |
|BATTELLE NORTHWEST 058812404  01/25/96   735       50( )      42  (713)     54.8     INDIUM PHOSPHIDE                           |
|BATTELLE NORTHWEST 056142708  01/13/97   731       50( )      38  (692)     58.7     VANADIUM PENTOXIDE                         |
|I. I. T. RESEARCH I058902906  10/05/94   735      100(5)      70  (702)     59.7     MAGNETIC FIELDS (EMF)                      |
|SOUTHERN RESEARCH  050520309  02/20/96   731       60(5)      52  (708)     46.6     O-NITROTOLUENE                             |
|SOUTHERN RESEARCH  050520508  11/14/95   732       50(5)      46  (727)     41.4     P-NITROTOLUENE                             |
|SOUTHERN RESEARCH  050516106  03/20/96   735       50(5)      34  (674)     59.5     RIDDELLIINE                                |
|________________________________________________________________________________________________________________________________|

























                                                                                  

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                                                 Toxicology Data Management System                                     Page: 3
 Version: 12/20/00                       Tumor Incidence for Selected Control Animal Groups

 Contract/Lab: All Laboratories                          Route: VARIOUS                                    Date of
 Species: MICE                                           Vehicle: NTP 2000 DIET                            Input File: 20-DEC-2000
 Strain: B6C3F1
 Length of Study: CHRONIC                   
                                             Incidence Data for Vehicle Control Groups
 __________________________________________________________________________________________________________________________________
|                                                   Male                                              Female                       |
 __________________________________________________________________________________________________________________________________
|#All Organs:                                                                                                                      |
|   Benign Tumors                       34/50 (68%)   40/100(40%)   29/49 (59%)         29/50 (58%)   28/99 (28%)   24/50 (48%)    |
|                                       16/50 (32%)   28/50 (56%)   29/50 (58%)         15/50 (30%)   13/50 (26%)   25/50 (50%)    |
|                                       31/50 (62%)   54/100(54%)   30/60 (50%)         19/50 (38%)   52/100(52%)   21/60 (35%)    |
|                                       25/50 (50%)   32/50 (64%)                       17/50 (34%)   15/50 (30%)                  |
| Overall Incidence               Total 348/659 (52.81%)Mean 53.93%  SD 10.58%    Total 258/659 (39.15%) Mean 39.03%  SD 11.04%    |
 __________________________________________________________________________________________________________________________________
|#All Organs:                                                                                                                      |
|   Malignant Tumors                    29/50 (58%)   32/100(32%)   24/49 (49%)         24/50 (48%)   24/99 (24%)   19/50 (38%)    |
|                                       21/50 (42%)   27/50 (54%)   21/50 (42%)         12/50 (24%)   12/50 (24%)   20/50 (40%)    |
|                                       27/50 (54%)   40/100(40%)   26/60 (43%)         17/50 (34%)   55/100(55%)   16/60 (27%)    |
|                                       14/50 (28%)   29/50 (58%)                        9/50 (18%)   21/50 (42%)                  |
| Overall Incidence               Total 290/659 (44.01%)Mean 45.48%  SD 10.08%    Total 229/659 (34.75%) Mean 33.99%  SD 11.65%    |
 __________________________________________________________________________________________________________________________________
|#All Organs:                                                                                                                      |
|   Malignant and Benign Tumors         45/50 (90%)   55/100(55%)   40/49 (82%)         39/50 (78%)   45/99 (45%)   33/50 (66%)    |
|                                       32/50 (64%)   40/50 (80%)   41/50 (82%)         23/50 (46%)   21/50 (42%)   35/50 (70%)    |
|                                       42/50 (84%)   71/100(71%)   45/60 (75%)         32/50 (64%)   78/100(78%)   33/60 (55%)    |
|                                       31/50 (62%)   44/50 (88%)                       21/50 (42%)   31/50 (62%)                  |
| Overall Incidence               Total 486/659 (73.75%)Mean 75.69%  SD 11.37%    Total 391/659 (59.33%) Mean 58.95%  SD 13.68%    |
 __________________________________________________________________________________________________________________________________
|#All Organs:                                                                                                                      |
|   Hemangioma                           2/50 (4%)     2/100(2%)     0/49 (0%)           0/50 (0%)     1/99 (1%)     2/50 (4%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     1/50 (2%)     |
|                                        0/50 (0%)     0/100(0%)     1/60 (2%)           0/50 (0%)     0/100(0%)     3/60 (5%)     |
|                                        0/50 (0%)     0/50 (0%)                         1/50 (2%)     0/50 (0%)                   |
| Overall Incidence               Total 5/659 (0.76%)   Mean 0.7%    SD 1.32%     Total 8/659 (1.21%)    Mean 1.27%   SD 1.79%     |
 __________________________________________________________________________________________________________________________________
|#All Organs:                                                                                                                      |
|   Hemangiosarcoma                      3/50 (6%)     3/100(3%)     3/49 (6%)           4/50 (8%)     0/99 (0%)     2/50 (4%)     |
|                                        3/50 (6%)     7/50 (14%)    3/50 (6%)           0/50 (0%)     1/50 (2%)     3/50 (6%)     |
|                                        1/50 (2%)     6/100(6%)     4/60 (7%)           2/50 (4%)     2/100(2%)     0/60 (0%)     |
|                                        1/50 (2%)     3/50 (6%)                         1/50 (2%)     0/50 (0%)                   |
| Overall Incidence               Total 37/659 (5.61%)  Mean 5.8%    SD 3.24%     Total 15/659 (2.28%)   Mean 2.55%   SD 2.7%      |
 __________________________________________________________________________________________________________________________________
|#All Organs:                                                                                                                      |
|   Hemangiosarcoma or Hemangioma        5/50 (10%)    5/100(5%)     3/49 (6%)           4/50 (8%)     1/99 (1%)     4/50 (8%)     |
|                                        3/50 (6%)     7/50 (14%)    3/50 (6%)           0/50 (0%)     1/50 (2%)     4/50 (8%)     |
|                                        1/50 (2%)     6/100(6%)     5/60 (8%)           2/50 (4%)     2/100(2%)     3/60 (5%)     |
|                                        1/50 (2%)     3/50 (6%)                         2/50 (4%)     0/50 (0%)                   |
| Overall Incidence               Total 42/659 (6.37%)  Mean 6.5%    SD 3.4%      Total 23/659 (3.49%)   Mean 3.82%   SD 3.12%     |
 __________________________________________________________________________________________________________________________________
|#All Organs:                                                                                                                      |
|   Histiocytic Sarcoma                  0/50 (0%)     0/100(0%)     0/49 (0%)           1/50 (2%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     1/50 (2%)     |
|                                        0/50 (0%)     1/100(1%)     1/60 (2%)           3/50 (6%)     2/100(2%)     0/60 (0%)     |
|                                        1/50 (2%)     0/50 (0%)                         0/50 (0%)     1/50 (2%)                   |
| Overall Incidence               Total 3/659 (0.46%)   Mean 0.42%   SD 0.76%     Total 8/659 (1.21%)    Mean 1.27%   SD 1.85%     |
 __________________________________________________________________________________________________________________________________

 *: Denominator is number of animals with tissues examined microscopically
 #: Denominator is number of animals necropsied
                                                 Toxicology Data Management System                                     Page: 4
 Version: 12/20/00                       Tumor Incidence for Selected Control Animal Groups

 Contract/Lab: All Laboratories                          Route: VARIOUS                                    Date of
 Species: MICE                                           Vehicle: NTP 2000 DIET                            Input File: 20-DEC-2000
 Strain: B6C3F1
 Length of Study: CHRONIC                   
                                             Incidence Data for Vehicle Control Groups
 __________________________________________________________________________________________________________________________________
|                                                   Male                                              Female                       |
 __________________________________________________________________________________________________________________________________
|#All Organs:                                                                                                                      |
|   Malignant Lymphoma: Histiocytic,     3/50 (6%)     4/100(4%)     2/49 (4%)           4/50 (8%)     7/99 (7%)     9/50 (18%)    |
|      Lymphocytic, Mixed, NOS, or       3/50 (6%)     1/50 (2%)     1/50 (2%)           6/50 (12%)    7/50 (14%)    8/50 (16%)    |
|      Undifferentiated Cell Type        2/50 (4%)     8/100(8%)     3/60 (5%)           7/50 (14%)   32/100(32%)    8/60 (13%)    |
|                                        3/50 (6%)     3/50 (6%)                         3/50 (6%)     7/50 (14%)                  |
| Overall Incidence               Total 33/659 (5.01%)  Mean 4.83%   SD 1.83%     Total 98/659 (14.87%)  Mean 14.04%  SD 7.05%     |
 __________________________________________________________________________________________________________________________________
|#All Organs:                                                                                                                      |
|   Osteosarcoma                         0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           1/50 (2%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     1/100(1%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 0/659 (0%)      Mean 0%      SD 0%        Total 2/659 (0.3%)     Mean 0.27%   SD 0.65%     |
 __________________________________________________________________________________________________________________________________
|#All Organs:                                                                                                                      |
|   Osteosarcoma or Osteoma              0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           1/50 (2%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     1/100(1%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 0/659 (0%)      Mean 0%      SD 0%        Total 2/659 (0.3%)     Mean 0.27%   SD 0.65%     |
 __________________________________________________________________________________________________________________________________
|*Adrenal Cortex:                                                                                                                  |
|   Adenoma                              3/50 (6%)     2/100(2%)     5/49 (10%)          0/50 (0%)     0/99 (0%)     0/49 (0%)     |
|                                        0/49 (0%)     0/50 (0%)     2/50 (4%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        1/50 (2%)     3/99 (3%)     2/60 (3%)           0/50 (0%)     0/92 (0%)     1/59 (2%)     |
|                                        3/49 (6%)     3/49 (6%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 24/655 (3.66%)  Mean 3.89%   SD 3.05%     Total 1/649 (0.15%)    Mean 0.15%   SD 0.51%     |
 __________________________________________________________________________________________________________________________________
|*Adrenal Cortex:                                                                                                                  |
|   Sarcoma                              0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/49 (0%)     |
|                                        0/49 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/99 (0%)     0/60 (0%)           0/50 (0%)     1/92 (1%)     0/59 (0%)     |
|                                        0/49 (0%)     0/49 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 0/655 (0%)      Mean 0%      SD 0%        Total 1/649 (0.15%)    Mean 0.1%    SD 0.33%     |
 __________________________________________________________________________________________________________________________________
|*Adrenal Medulla:                                                                                                                 |
|   Pheochromocytoma Benign              0/50 (0%)     0/99 (0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/49 (0%)     |
|                                        0/49 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     2/49 (4%)     |
|                                        0/50 (0%)     1/98 (1%)     0/60 (0%)           2/49 (4%)     0/90 (0%)     0/59 (0%)     |
|                                        0/49 (0%)     0/49 (0%)                         0/50 (0%)     0/49 (0%)                   |
| Overall Incidence               Total 1/653 (0.15%)   Mean 0.09%   SD 0.31%     Total 4/644 (0.62%)    Mean 0.74%   SD 1.65%     |
 __________________________________________________________________________________________________________________________________
|*Adrenal Medulla:                                                                                                                 |
|   Pheochromocytoma Malignant           0/50 (0%)     0/99 (0%)     0/49 (0%)           0/50 (0%)     1/99 (1%)     0/49 (0%)     |
|                                        0/49 (0%)     0/50 (0%)     0/50 (0%)           1/50 (2%)     0/50 (0%)     0/49 (0%)     |
|                                        0/50 (0%)     2/98 (2%)     0/60 (0%)           0/49 (0%)     0/90 (0%)     0/59 (0%)     |
|                                        0/49 (0%)     1/49 (2%)                         0/50 (0%)     0/49 (0%)                   |
| Overall Incidence               Total 3/653 (0.46%)   Mean 0.37%   SD 0.83%     Total 2/644 (0.31%)    Mean 0.27%   SD 0.65%     |
 __________________________________________________________________________________________________________________________________

 *: Denominator is number of animals with tissues examined microscopically
 #: Denominator is number of animals necropsied
                                                 Toxicology Data Management System                                     Page: 5
 Version: 12/20/00                       Tumor Incidence for Selected Control Animal Groups

 Contract/Lab: All Laboratories                          Route: VARIOUS                                    Date of
 Species: MICE                                           Vehicle: NTP 2000 DIET                            Input File: 20-DEC-2000
 Strain: B6C3F1
 Length of Study: CHRONIC                   
                                             Incidence Data for Vehicle Control Groups
 __________________________________________________________________________________________________________________________________
|                                                   Male                                              Female                       |
 __________________________________________________________________________________________________________________________________
|*Adrenal Medulla:                                                                                                                 |
|   Pheochromocytoma: Benign,            0/50 (0%)     0/99 (0%)     0/49 (0%)           0/50 (0%)     1/99 (1%)     0/49 (0%)     |
|      Complex, Malignant, NOS           0/49 (0%)     0/50 (0%)     0/50 (0%)           1/50 (2%)     0/50 (0%)     2/49 (4%)     |
|                                        0/50 (0%)     2/98 (2%)     0/60 (0%)           2/49 (4%)     0/90 (0%)     0/59 (0%)     |
|                                        0/49 (0%)     1/49 (2%)                         0/50 (0%)     0/49 (0%)                   |
| Overall Incidence               Total 3/653 (0.46%)   Mean 0.37%   SD 0.83%     Total 6/644 (0.93%)    Mean 1.02%   SD 1.64%     |
 __________________________________________________________________________________________________________________________________
|*Bone Marrow:                                                                                                                     |
|   Hemangiosarcoma                      2/50 (4%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     2/50 (4%)     1/49 (2%)           0/50 (0%)     0/50 (0%)     1/50 (2%)     |
|                                        0/50 (0%)     0/99 (0%)     0/60 (0%)           1/50 (2%)     0/96 (0%)     0/60 (0%)     |
|                                        0/50 (0%)     1/50 (2%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 6/657 (0.91%)   Mean 1.09%   SD 1.64%     Total 2/655 (0.31%)    Mean 0.36%   SD 0.81%     |
 __________________________________________________________________________________________________________________________________
|*Bone Marrow:                                                                                                                     |
|   Mast Cell Tumor Benign               0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/49 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     1/99 (1%)     0/60 (0%)           0/50 (0%)     0/96 (0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 1/657 (0.15%)   Mean 0.09%   SD 0.3%      Total 0/655 (0%)       Mean 0%      SD 0%        |
 __________________________________________________________________________________________________________________________________
|*Bone Marrow:                                                                                                                     |
|   Mast Cell Tumor Malignant            0/50 (0%)     1/100(1%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        1/50 (2%)     0/50 (0%)     0/49 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/99 (0%)     1/60 (2%)           0/50 (0%)     0/96 (0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 3/657 (0.46%)   Mean 0.42%   SD 0.76%     Total 0/655 (0%)       Mean 0%      SD 0%        |
 __________________________________________________________________________________________________________________________________
|#Bone:                                                                                                                            |
|   Fibrosarcoma                         1/50 (2%)     0/100(0%)     0/49 (0%)           0/50 (0%)     1/99 (1%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 1/659 (0.15%)   Mean 0.18%   SD 0.6%      Total 1/659 (0.15%)    Mean 0.09%   SD 0.3%      |
 __________________________________________________________________________________________________________________________________
|#Bone:                                                                                                                            |
|   Osteosarcoma                         0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           1/50 (2%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     1/100(1%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 0/659 (0%)      Mean 0%      SD 0%        Total 2/659 (0.3%)     Mean 0.27%   SD 0.65%     |
 __________________________________________________________________________________________________________________________________
|#Bone:                                                                                                                            |
|   Osteosarcoma or Osteoma              0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           1/50 (2%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     1/100(1%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 0/659 (0%)      Mean 0%      SD 0%        Total 2/659 (0.3%)     Mean 0.27%   SD 0.65%     |
 __________________________________________________________________________________________________________________________________

 *: Denominator is number of animals with tissues examined microscopically
 #: Denominator is number of animals necropsied
                                                 Toxicology Data Management System                                     Page: 6
 Version: 12/20/00                       Tumor Incidence for Selected Control Animal Groups

 Contract/Lab: All Laboratories                          Route: VARIOUS                                    Date of
 Species: MICE                                           Vehicle: NTP 2000 DIET                            Input File: 20-DEC-2000
 Strain: B6C3F1
 Length of Study: CHRONIC                   
                                             Incidence Data for Vehicle Control Groups
 __________________________________________________________________________________________________________________________________
|                                                   Male                                              Female                       |
 __________________________________________________________________________________________________________________________________
|*Brain:                                                                                                                           |
|   Meningioma Malignant                 0/50 (0%)     0/100(0%)     0/49 (0%)           1/50 (2%)     0/98 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/99 (0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 0/659 (0%)      Mean 0%      SD 0%        Total 1/657 (0.15%)    Mean 0.18%   SD 0.6%      |
 __________________________________________________________________________________________________________________________________
|*Brain:                                                                                                                           |
|   Meningioma: Benign, Malignant, NOS   0/50 (0%)     0/100(0%)     0/49 (0%)           1/50 (2%)     0/98 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/99 (0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 0/659 (0%)      Mean 0%      SD 0%        Total 1/657 (0.15%)    Mean 0.18%   SD 0.6%      |
 __________________________________________________________________________________________________________________________________
|*Brain:                                                                                                                           |
|   Oligodendroglioma Malignant          0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/98 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     1/50 (2%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/99 (0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 1/659 (0.15%)   Mean 0.18%   SD 0.6%      Total 0/657 (0%)       Mean 0%      SD 0%        |
 __________________________________________________________________________________________________________________________________
|*Brain:                                                                                                                           |
|   Oligodendroglioma, Glioma, or        0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/98 (0%)     0/50 (0%)     |
|      Astrocytoma                       0/50 (0%)     0/50 (0%)     1/50 (2%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/99 (0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 1/659 (0.15%)   Mean 0.18%   SD 0.6%      Total 0/657 (0%)       Mean 0%      SD 0%        |
 __________________________________________________________________________________________________________________________________
|*Brain:                                                                                                                           |
|   Sarcoma                              0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/98 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     1/50 (2%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/99 (0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 1/659 (0.15%)   Mean 0.18%   SD 0.6%      Total 0/657 (0%)       Mean 0%      SD 0%        |
 __________________________________________________________________________________________________________________________________
|#Clitoral/Preputial Gland:                                                                                                        |
|   Adenoma                              0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                        0/50 (0%)     1/50 (2%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 1/659 (0.15%)   Mean 0.18%   SD 0.6%      Total 0/659 (0%)       Mean 0%      SD 0%        |
 __________________________________________________________________________________________________________________________________
|#Clitoral/Preputial Gland:                                                                                                        |
|   Carcinoma                            0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     1/99 (1%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     1/50 (2%)                   |
| Overall Incidence               Total 0/659 (0%)      Mean 0%      SD 0%        Total 2/659 (0.3%)     Mean 0.27%   SD 0.65%     |
 __________________________________________________________________________________________________________________________________

 *: Denominator is number of animals with tissues examined microscopically
 #: Denominator is number of animals necropsied
                                                 Toxicology Data Management System                                     Page: 7
 Version: 12/20/00                       Tumor Incidence for Selected Control Animal Groups

 Contract/Lab: All Laboratories                          Route: VARIOUS                                    Date of
 Species: MICE                                           Vehicle: NTP 2000 DIET                            Input File: 20-DEC-2000
 Strain: B6C3F1
 Length of Study: CHRONIC                   
                                             Incidence Data for Vehicle Control Groups
 __________________________________________________________________________________________________________________________________
|                                                   Male                                              Female                       |
 __________________________________________________________________________________________________________________________________
|#Clitoral/Preputial Gland:                                                                                                        |
|   Carcinoma or Adenoma                 0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     1/99 (1%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                        0/50 (0%)     1/50 (2%)                         0/50 (0%)     1/50 (2%)                   |
| Overall Incidence               Total 1/659 (0.15%)   Mean 0.18%   SD 0.6%      Total 2/659 (0.3%)     Mean 0.27%   SD 0.65%     |
 __________________________________________________________________________________________________________________________________
|#Ear:                                                                                                                             |
|   Neural Crest Tumor, Malignant        0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     1/60 (2%)           0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 1/659 (0.15%)   Mean 0.15%   SD 0.5%      Total 0/659 (0%)       Mean 0%      SD 0%        |
 __________________________________________________________________________________________________________________________________
|*Gallbladder:                                                                                                                     |
|   Sarcoma                              0/50 (0%)     0/100(0%)     0/46 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/49 (0%)     0/50 (0%)     0/43 (0%)           0/49 (0%)     0/48 (0%)     0/46 (0%)     |
|                                        0/42 (0%)     0/84 (0%)     0/54 (0%)           0/46 (0%)     0/70 (0%)     0/54 (0%)     |
|                                        0/49 (0%)     0/44 (0%)                         0/49 (0%)     1/45 (2%)                   |
| Overall Incidence               Total 0/611 (0%)      Mean 0%      SD 0%        Total 1/606 (0.17%)    Mean 0.2%    SD 0.67%     |
 __________________________________________________________________________________________________________________________________
|#Harderian Gland:                                                                                                                 |
|   Adenoma                              5/50 (10%)    4/100(4%)     3/49 (6%)          10/50 (20%)    3/99 (3%)     2/50 (4%)     |
|                                        5/50 (10%)    4/50 (8%)     1/50 (2%)           3/50 (6%)     0/50 (0%)     3/50 (6%)     |
|                                        8/50 (16%)   12/100(12%)    4/60 (7%)           2/50 (4%)    10/100(10%)    4/60 (7%)     |
|                                        3/50 (6%)     4/50 (8%)                         2/50 (4%)     2/50 (4%)                   |
| Overall Incidence               Total 53/659 (8.04%)  Mean 8.07%   SD 3.86%     Total 41/659 (6.22%)   Mean 6.15%   SD 5.22%     |
 __________________________________________________________________________________________________________________________________
|#Harderian Gland:                                                                                                                 |
|   Carcinoma                            1/50 (2%)     0/100(0%)     0/49 (0%)           1/50 (2%)     1/99 (1%)     2/50 (4%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     1/60 (2%)           0/50 (0%)     2/100(2%)     1/60 (2%)     |
|                                        0/50 (0%)     2/50 (4%)                         0/50 (0%)     2/50 (4%)                   |
| Overall Incidence               Total 4/659 (0.61%)   Mean 0.7%    SD 1.32%     Total 9/659 (1.37%)    Mean 1.33%   SD 1.56%     |
 __________________________________________________________________________________________________________________________________
|#Harderian Gland:                                                                                                                 |
|   Carcinoma or Adenoma                 6/50 (12%)    4/100(4%)     3/49 (6%)          11/50 (22%)    4/99 (4%)     4/50 (8%)     |
|                                        5/50 (10%)    4/50 (8%)     1/50 (2%)           3/50 (6%)     0/50 (0%)     3/50 (6%)     |
|                                        8/50 (16%)   12/100(12%)    5/60 (8%)           2/50 (4%)    12/100(12%)    5/60 (8%)     |
|                                        3/50 (6%)     6/50 (12%)                        2/50 (4%)     4/50 (8%)                   |
| Overall Incidence               Total 57/659 (8.65%)  Mean 8.77%   SD 4.11%     Total 50/659 (7.59%)   Mean 7.49%   SD 5.74%     |
 __________________________________________________________________________________________________________________________________
|*Heart:                                                                                                                           |
|   Schwannoma Malignant                 1/50 (2%)     0/100(0%)     0/48 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/98 (0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 1/658 (0.15%)   Mean 0.18%   SD 0.6%      Total 0/657 (0%)       Mean 0%      SD 0%        |
 __________________________________________________________________________________________________________________________________

 *: Denominator is number of animals with tissues examined microscopically
 #: Denominator is number of animals necropsied
                                                 Toxicology Data Management System                                     Page: 8
 Version: 12/20/00                       Tumor Incidence for Selected Control Animal Groups

 Contract/Lab: All Laboratories                          Route: VARIOUS                                    Date of
 Species: MICE                                           Vehicle: NTP 2000 DIET                            Input File: 20-DEC-2000
 Strain: B6C3F1
 Length of Study: CHRONIC                   
                                             Incidence Data for Vehicle Control Groups
 __________________________________________________________________________________________________________________________________
|                                                   Male                                              Female                       |
 __________________________________________________________________________________________________________________________________
|#Intestine Large: Cecum                                                                                                           |
|   Carcinoma                            0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                        1/50 (2%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 1/659 (0.15%)   Mean 0.18%   SD 0.6%      Total 0/659 (0%)       Mean 0%      SD 0%        |
 __________________________________________________________________________________________________________________________________
|#Intestine Large: Cecum                                                                                                           |
|   Carcinoma or Adenoma                 0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                        1/50 (2%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 1/659 (0.15%)   Mean 0.18%   SD 0.6%      Total 0/659 (0%)       Mean 0%      SD 0%        |
 __________________________________________________________________________________________________________________________________
|#Intestine Large: Cecum                                                                                                           |
|   Leiomyoma                            0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     3/50 (6%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 0/659 (0%)      Mean 0%      SD 0%        Total 3/659 (0.46%)    Mean 0.55%   SD 1.81%     |
 __________________________________________________________________________________________________________________________________
|#Intestine Large: Cecum                                                                                                           |
|   Leiomyosarcoma                       0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     1/50 (2%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 0/659 (0%)      Mean 0%      SD 0%        Total 1/659 (0.15%)    Mean 0.18%   SD 0.6%      |
 __________________________________________________________________________________________________________________________________
|#Intestine Small: Duodenum                                                                                                        |
|   Adenoma                              0/50 (0%)     0/100(0%)     2/49 (4%)           0/50 (0%)     0/99 (0%)     1/50 (2%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 2/659 (0.3%)    Mean 0.37%   SD 1.23%     Total 1/659 (0.15%)    Mean 0.18%   SD 0.6%      |
 __________________________________________________________________________________________________________________________________
|#Intestine Small: Duodenum                                                                                                        |
|   Hemangiosarcoma                      0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     1/60 (2%)           0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 1/659 (0.15%)   Mean 0.15%   SD 0.5%      Total 0/659 (0%)       Mean 0%      SD 0%        |
 __________________________________________________________________________________________________________________________________
|#Intestine Small: Duodenum                                                                                                        |
|   Polyp Adenomatous                    1/50 (2%)     2/100(2%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     2/50 (4%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           1/50 (2%)     1/100(1%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 5/659 (0.76%)   Mean 0.73%   SD 1.35%     Total 2/659 (0.3%)     Mean 0.27%   SD 0.65%     |
 __________________________________________________________________________________________________________________________________

 *: Denominator is number of animals with tissues examined microscopically
 #: Denominator is number of animals necropsied
                                                 Toxicology Data Management System                                     Page: 9
 Version: 12/20/00                       Tumor Incidence for Selected Control Animal Groups

 Contract/Lab: All Laboratories                          Route: VARIOUS                                    Date of
 Species: MICE                                           Vehicle: NTP 2000 DIET                            Input File: 20-DEC-2000
 Strain: B6C3F1
 Length of Study: CHRONIC                   
                                             Incidence Data for Vehicle Control Groups
 __________________________________________________________________________________________________________________________________
|                                                   Male                                              Female                       |
 __________________________________________________________________________________________________________________________________
|#Intestine Small: Ileum                                                                                                           |
|   Carcinoma                            0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        1/50 (2%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 1/659 (0.15%)   Mean 0.18%   SD 0.6%      Total 0/659 (0%)       Mean 0%      SD 0%        |
 __________________________________________________________________________________________________________________________________
|#Intestine Small: Jejunum                                                                                                         |
|   Adenoma                              0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     1/50 (2%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 1/659 (0.15%)   Mean 0.18%   SD 0.6%      Total 0/659 (0%)       Mean 0%      SD 0%        |
 __________________________________________________________________________________________________________________________________
|#Intestine Small: Jejunum                                                                                                         |
|   Carcinoma                            2/50 (4%)     3/100(3%)     1/49 (2%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     5/50 (10%)    0/50 (0%)           0/50 (0%)     0/50 (0%)     1/50 (2%)     |
|                                        0/50 (0%)     1/100(1%)     2/60 (3%)           0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 14/659 (2.12%)  Mean 2.12%   SD 3.03%     Total 1/659 (0.15%)    Mean 0.18%   SD 0.6%      |
 __________________________________________________________________________________________________________________________________
|#Intestine Small: Site Unspecified                                                                                                |
|   Adenoma                              0/50 (0%)     0/100(0%)     2/49 (4%)           0/50 (0%)     0/99 (0%)     1/50 (2%)     |
|                                        0/50 (0%)     0/50 (0%)     1/50 (2%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 3/659 (0.46%)   Mean 0.55%   SD 1.32%     Total 1/659 (0.15%)    Mean 0.18%   SD 0.6%      |
 __________________________________________________________________________________________________________________________________
|#Intestine Small: Site Unspecified                                                                                                |
|   Carcinoma                            2/50 (4%)     3/100(3%)     1/49 (2%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     5/50 (10%)    0/50 (0%)           0/50 (0%)     0/50 (0%)     1/50 (2%)     |
|                                        1/50 (2%)     1/100(1%)     2/60 (3%)           0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 15/659 (2.28%)  Mean 2.31%   SD 2.95%     Total 1/659 (0.15%)    Mean 0.18%   SD 0.6%      |
 __________________________________________________________________________________________________________________________________
|#Intestine Small: Site Unspecified                                                                                                |
|   Carcinoma or Adenoma                 2/50 (4%)     3/100(3%)     3/49 (6%)           0/50 (0%)     0/99 (0%)     1/50 (2%)     |
|                                        0/50 (0%)     5/50 (10%)    1/50 (2%)           0/50 (0%)     0/50 (0%)     1/50 (2%)     |
|                                        1/50 (2%)     1/100(1%)     2/60 (3%)           0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 18/659 (2.73%)  Mean 2.86%   SD 3.04%     Total 2/659 (0.3%)     Mean 0.36%   SD 0.81%     |
 __________________________________________________________________________________________________________________________________
|#Intestine Small: Site Unspecified                                                                                                |
|   Hemangiosarcoma                      0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     1/60 (2%)           0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 1/659 (0.15%)   Mean 0.15%   SD 0.5%      Total 0/659 (0%)       Mean 0%      SD 0%        |
 __________________________________________________________________________________________________________________________________

 *: Denominator is number of animals with tissues examined microscopically
 #: Denominator is number of animals necropsied
                                                 Toxicology Data Management System                                     Page: 10
 Version: 12/20/00                       Tumor Incidence for Selected Control Animal Groups

 Contract/Lab: All Laboratories                          Route: VARIOUS                                    Date of
 Species: MICE                                           Vehicle: NTP 2000 DIET                            Input File: 20-DEC-2000
 Strain: B6C3F1
 Length of Study: CHRONIC                   
                                             Incidence Data for Vehicle Control Groups
 __________________________________________________________________________________________________________________________________
|                                                   Male                                              Female                       |
 __________________________________________________________________________________________________________________________________
|#Intestine Small: Site Unspecified                                                                                                |
|   Polyp Adenomatous                    1/50 (2%)     2/100(2%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     2/50 (4%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           1/50 (2%)     1/100(1%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 5/659 (0.76%)   Mean 0.73%   SD 1.35%     Total 2/659 (0.3%)     Mean 0.27%   SD 0.65%     |
 __________________________________________________________________________________________________________________________________
|*Islets, Pancreatic:                                                                                                              |
|   Adenoma                              2/50 (4%)     1/100(1%)     2/49 (4%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     3/50 (6%)     3/50 (6%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        1/50 (2%)     1/99 (1%)     0/59 (0%)           0/50 (0%)     2/87 (2%)     0/60 (0%)     |
|                                        0/50 (0%)     3/49 (6%)                         0/49 (0%)     0/49 (0%)                   |
| Overall Incidence               Total 16/656 (2.44%)  Mean 2.75%   SD 2.55%     Total 2/644 (0.31%)    Mean 0.21%   SD 0.69%     |
 __________________________________________________________________________________________________________________________________
|*Islets, Pancreatic:                                                                                                              |
|   Carcinoma                            0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           1/50 (2%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     2/99 (2%)     0/59 (0%)           0/50 (0%)     0/87 (0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/49 (0%)                         0/49 (0%)     0/49 (0%)                   |
| Overall Incidence               Total 2/656 (0.3%)    Mean 0.18%   SD 0.61%     Total 1/644 (0.16%)    Mean 0.18%   SD 0.6%      |
 __________________________________________________________________________________________________________________________________
|*Islets, Pancreatic:                                                                                                              |
|   Carcinoma or Adenoma                 2/50 (4%)     1/100(1%)     2/49 (4%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     3/50 (6%)     3/50 (6%)           1/50 (2%)     0/50 (0%)     0/50 (0%)     |
|                                        1/50 (2%)     3/99 (3%)     0/59 (0%)           0/50 (0%)     2/87 (2%)     0/60 (0%)     |
|                                        0/50 (0%)     3/49 (6%)                         0/49 (0%)     0/49 (0%)                   |
| Overall Incidence               Total 18/656 (2.74%)  Mean 2.93%   SD 2.49%     Total 3/644 (0.47%)    Mean 0.39%   SD 0.87%     |
 __________________________________________________________________________________________________________________________________
|*Kidney: Renal Tubule                                                                                                             |
|   Adenoma                              1/50 (2%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     1/99 (1%)     0/58 (0%)           0/50 (0%)     0/92 (0%)     0/59 (0%)     |
|                                        0/50 (0%)     1/49 (2%)                         0/49 (0%)     0/49 (0%)                   |
| Overall Incidence               Total 3/655 (0.46%)   Mean 0.46%   SD 0.83%     Total 0/648 (0%)       Mean 0%      SD 0%        |
 __________________________________________________________________________________________________________________________________
|*Kidney: Renal Tubule                                                                                                             |
|   Carcinoma                            0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     1/99 (1%)     0/58 (0%)           0/50 (0%)     0/92 (0%)     0/59 (0%)     |
|                                        0/50 (0%)     0/49 (0%)                         0/49 (0%)     0/49 (0%)                   |
| Overall Incidence               Total 1/655 (0.15%)   Mean 0.09%   SD 0.3%      Total 0/648 (0%)       Mean 0%      SD 0%        |
 __________________________________________________________________________________________________________________________________
|*Kidney: Renal Tubule                                                                                                             |
|   Carcinoma or Adenoma                 1/50 (2%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     2/99 (2%)     0/58 (0%)           0/50 (0%)     0/92 (0%)     0/59 (0%)     |
|                                        0/50 (0%)     1/49 (2%)                         0/49 (0%)     0/49 (0%)                   |
| Overall Incidence               Total 4/655 (0.61%)   Mean 0.55%   SD 0.94%     Total 0/648 (0%)       Mean 0%      SD 0%        |
 __________________________________________________________________________________________________________________________________

 *: Denominator is number of animals with tissues examined microscopically
 #: Denominator is number of animals necropsied
                                                 Toxicology Data Management System                                     Page: 11
 Version: 12/20/00                       Tumor Incidence for Selected Control Animal Groups

 Contract/Lab: All Laboratories                          Route: VARIOUS                                    Date of
 Species: MICE                                           Vehicle: NTP 2000 DIET                            Input File: 20-DEC-2000
 Strain: B6C3F1
 Length of Study: CHRONIC                   
                                             Incidence Data for Vehicle Control Groups
 __________________________________________________________________________________________________________________________________
|                                                   Male                                              Female                       |
 __________________________________________________________________________________________________________________________________
|*Kidney: Renal Tubule                                                                                                             |
|   Hemangiosarcoma                      0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     1/50 (2%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/99 (0%)     0/58 (0%)           0/50 (0%)     0/92 (0%)     0/59 (0%)     |
|                                        0/50 (0%)     0/49 (0%)                         0/49 (0%)     0/49 (0%)                   |
| Overall Incidence               Total 0/655 (0%)      Mean 0%      SD 0%        Total 1/648 (0.15%)    Mean 0.18%   SD 0.6%      |
 __________________________________________________________________________________________________________________________________
|*Liver:                                                                                                                           |
|   Hemangiosarcoma                      2/50 (4%)     2/100(2%)     1/49 (2%)           2/50 (4%)     0/99 (0%)     0/50 (0%)     |
|                                        2/50 (4%)     2/50 (4%)     2/50 (4%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        1/50 (2%)     4/100(4%)     1/60 (2%)           0/50 (0%)     1/98 (1%)     0/60 (0%)     |
|                                        1/50 (2%)     2/50 (4%)                         0/49 (0%)     0/49 (0%)                   |
| Overall Incidence               Total 20/659 (3.03%)  Mean 3.06%   SD 1.08%     Total 3/655 (0.46%)    Mean 0.46%   SD 1.21%     |
 __________________________________________________________________________________________________________________________________
|*Liver:                                                                                                                           |
|   Hepatoblastoma                       0/50 (0%)     0/100(0%)     1/49 (2%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     5/50 (10%)    0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     2/100(2%)     1/60 (2%)           0/50 (0%)     0/98 (0%)     0/60 (0%)     |
|                                        0/50 (0%)     3/50 (6%)                         0/49 (0%)     0/49 (0%)                   |
| Overall Incidence               Total 12/659 (1.82%)  Mean 1.97%   SD 3.23%     Total 0/655 (0%)       Mean 0%      SD 0%        |
 __________________________________________________________________________________________________________________________________
|*Liver:                                                                                                                           |
|   Hepatocellular Adenoma              23/50 (46%)   20/100(20%)   17/49 (35%)         14/50 (28%)    8/99 (8%)     9/50 (18%)    |
|                                        6/50 (12%)   19/50 (38%)   17/50 (34%)          4/50 (8%)     9/50 (18%)   12/50 (24%)    |
|                                       15/50 (30%)   30/100(30%)   18/60 (30%)          6/50 (12%)   17/98 (17%)    7/60 (12%)    |
|                                       14/50 (28%)   16/50 (32%)                        6/49 (12%)    9/49 (18%)                  |
| Overall Incidence               Total 195/659 (29.59%)Mean 30.43%  SD 8.88%     Total 101/655 (15.42%) Mean 15.97%  SD 6.32%     |
 __________________________________________________________________________________________________________________________________
|*Liver:                                                                                                                           |
|   Hepatocellular Carcinoma            14/50 (28%)   13/100(13%)   13/49 (27%)          7/50 (14%)    4/99 (4%)     2/50 (4%)     |
|                                        9/50 (18%)    9/50 (18%)   11/50 (22%)          3/50 (6%)     2/50 (4%)     6/50 (12%)    |
|                                       14/50 (28%)   19/100(19%)   12/60 (20%)          6/50 (12%)    6/98 (6%)     2/60 (3%)     |
|                                        8/50 (16%)   23/50 (46%)                        3/49 (6%)     8/49 (16%)                  |
| Overall Incidence               Total 145/659 (22%)   Mean 23.14%  SD 9.03%     Total 49/655 (7.48%)   Mean 8%      SD 4.67%     |
 __________________________________________________________________________________________________________________________________
|*Liver:                                                                                                                           |
|   Hepatocellular Carcinoma or         14/50 (28%)   13/100(13%)   14/49 (29%)          7/50 (14%)    4/99 (4%)     2/50 (4%)     |
|      Hepatoblastoma                    9/50 (18%)   12/50 (24%)   11/50 (22%)          3/50 (6%)     2/50 (4%)     6/50 (12%)    |
|                                       14/50 (28%)   21/100(21%)   13/60 (22%)          6/50 (12%)    6/98 (6%)     2/60 (3%)     |
|                                        8/50 (16%)   24/50 (48%)                        3/49 (6%)     8/49 (16%)                  |
| Overall Incidence               Total 153/659 (23.22%)Mean 24.39%  SD 9.31%     Total 49/655 (7.48%)   Mean 8%      SD 4.67%     |
 __________________________________________________________________________________________________________________________________
|*Liver:                                                                                                                           |
|   Hepatocellular Carcinoma or         32/50 (64%)   28/100(28%)   24/49 (49%)         20/50 (40%)   12/99 (12%)   10/50 (20%)    |
|      Hepatocellular Adenoma           15/50 (30%)   24/50 (48%)   26/50 (52%)          6/50 (12%)   10/50 (20%)   18/50 (36%)    |
|                                       26/50 (52%)   46/100(46%)   27/60 (45%)         12/50 (24%)   22/98 (22%)    9/60 (15%)    |
|                                       20/50 (40%)   36/50 (72%)                        8/49 (16%)   16/49 (33%)                  |
| Overall Incidence               Total 304/659 (46.13%)Mean 47.82%  SD 12.91%    Total 143/655 (21.83%) Mean 22.78%  SD 9.58%     |
 __________________________________________________________________________________________________________________________________

 *: Denominator is number of animals with tissues examined microscopically
 #: Denominator is number of animals necropsied
                                                 Toxicology Data Management System                                     Page: 12
 Version: 12/20/00                       Tumor Incidence for Selected Control Animal Groups

 Contract/Lab: All Laboratories                          Route: VARIOUS                                    Date of
 Species: MICE                                           Vehicle: NTP 2000 DIET                            Input File: 20-DEC-2000
 Strain: B6C3F1
 Length of Study: CHRONIC                   
                                             Incidence Data for Vehicle Control Groups
 __________________________________________________________________________________________________________________________________
|                                                   Male                                              Female                       |
 __________________________________________________________________________________________________________________________________
|*Liver:                                                                                                                           |
|   Hepatocellular Carcinoma,           32/50 (64%)   28/100(28%)   24/49 (49%)         20/50 (40%)   12/99 (12%)   10/50 (20%)    |
|      Hepatocellular Adenoma, or       15/50 (30%)   26/50 (52%)   26/50 (52%)          6/50 (12%)   10/50 (20%)   18/50 (36%)    |
|      Hepatoblastoma                   26/50 (52%)   47/100(47%)   28/60 (47%)         12/50 (24%)   22/98 (22%)    9/60 (15%)    |
|                                       20/50 (40%)   36/50 (72%)                        8/49 (16%)   16/49 (33%)                  |
| Overall Incidence               Total 308/659 (46.74%)Mean 48.42%  SD 12.92%    Total 143/655 (21.83%) Mean 22.78%  SD 9.58%     |
 __________________________________________________________________________________________________________________________________
|*Liver:                                                                                                                           |
|   Hepatocholangiocarcinoma             0/50 (0%)     0/100(0%)     1/49 (2%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     1/50 (2%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     1/98 (1%)     0/60 (0%)     |
|                                        2/50 (4%)     0/50 (0%)                         0/49 (0%)     0/49 (0%)                   |
| Overall Incidence               Total 3/659 (0.46%)   Mean 0.55%   SD 1.3%      Total 2/655 (0.31%)    Mean 0.27%   SD 0.65%     |
 __________________________________________________________________________________________________________________________________
|*Liver:                                                                                                                           |
|   Sarcoma                              0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/98 (0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/49 (0%)     1/49 (2%)                   |
| Overall Incidence               Total 0/659 (0%)      Mean 0%      SD 0%        Total 1/655 (0.15%)    Mean 0.19%   SD 0.62%     |
 __________________________________________________________________________________________________________________________________
|*Lung:                                                                                                                            |
|   Adenoma                              0/50 (0%)     0/100(0%)     0/49 (0%)           1/50 (2%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/95 (0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 0/659 (0%)      Mean 0%      SD 0%        Total 1/654 (0.15%)    Mean 0.18%   SD 0.6%      |
 __________________________________________________________________________________________________________________________________
|*Lung:                                                                                                                            |
|   Alveolar/Bronchiolar Adenoma        10/50 (20%)   12/100(12%)    2/49 (4%)           4/50 (8%)     5/99 (5%)     6/50 (12%)    |
|                                        6/50 (12%)   10/50 (20%)   13/50 (26%)          0/50 (0%)     1/50 (2%)     3/50 (6%)     |
|                                       13/50 (26%)   26/100(26%)    9/60 (15%)          1/50 (2%)     9/95 (9%)     2/60 (3%)     |
|                                        6/50 (12%)   12/50 (24%)                        5/50 (10%)    1/50 (2%)                   |
| Overall Incidence               Total 119/659 (18.06%)Mean 17.92%  SD 7.39%     Total 37/654 (5.66%)   Mean 5.44%   SD 3.96%     |
 __________________________________________________________________________________________________________________________________
|*Lung:                                                                                                                            |
|   Alveolar/Bronchiolar Carcinoma       4/50 (8%)     9/100(9%)     4/49 (8%)           2/50 (4%)     6/99 (6%)     1/50 (2%)     |
|                                        7/50 (14%)    4/50 (8%)     6/50 (12%)          0/50 (0%)     0/50 (0%)     1/50 (2%)     |
|                                       12/50 (24%)    8/100(8%)     5/60 (8%)           0/50 (0%)     2/95 (2%)     3/60 (5%)     |
|                                        2/50 (4%)     7/50 (14%)                        1/50 (2%)     1/50 (2%)                   |
| Overall Incidence               Total 68/659 (10.32%) Mean 10.68%  SD 5.31%     Total 17/654 (2.6%)    Mean 2.29%   SD 2.01%     |
 __________________________________________________________________________________________________________________________________
|*Lung:                                                                                                                            |
|   Alveolar/Bronchiolar Carcinoma or   14/50 (28%)   20/100(20%)    6/49 (12%)          6/50 (12%)   11/99 (11%)    6/50 (12%)    |
|      Alveolar/Bronchiolar Adenoma     13/50 (26%)   13/50 (26%)   18/50 (36%)          0/50 (0%)     1/50 (2%)     4/50 (8%)     |
|                                       22/50 (44%)   30/100(30%)   14/60 (23%)          1/50 (2%)    11/95 (12%)    5/60 (8%)     |
|                                        8/50 (16%)   18/50 (36%)                        6/50 (12%)    2/50 (4%)                   |
| Overall Incidence               Total 176/659 (26.71%)Mean 27.05%  SD 9.3%      Total 53/654 (8.1%)    Mean 7.55%   SD 4.69%     |
 __________________________________________________________________________________________________________________________________

 *: Denominator is number of animals with tissues examined microscopically
 #: Denominator is number of animals necropsied
                                                 Toxicology Data Management System                                     Page: 13
 Version: 12/20/00                       Tumor Incidence for Selected Control Animal Groups

 Contract/Lab: All Laboratories                          Route: VARIOUS                                    Date of
 Species: MICE                                           Vehicle: NTP 2000 DIET                            Input File: 20-DEC-2000
 Strain: B6C3F1
 Length of Study: CHRONIC                   
                                             Incidence Data for Vehicle Control Groups
 __________________________________________________________________________________________________________________________________
|                                                   Male                                              Female                       |
 __________________________________________________________________________________________________________________________________
|*Lung:                                                                                                                            |
|   Hemangiosarcoma                      0/50 (0%)     1/100(1%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/95 (0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 1/659 (0.15%)   Mean 0.09%   SD 0.3%      Total 0/654 (0%)       Mean 0%      SD 0%        |
 __________________________________________________________________________________________________________________________________
|#Lymph Node, Mesenteric:                                                                                                          |
|   Fibrous Histiocytoma                 0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           1/50 (2%)     0/100(0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 0/659 (0%)      Mean 0%      SD 0%        Total 1/659 (0.15%)    Mean 0.18%   SD 0.6%      |
 __________________________________________________________________________________________________________________________________
|#Lymph Node, Mesenteric:                                                                                                          |
|   Hemangioma                           2/50 (4%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 2/659 (0.3%)    Mean 0.36%   SD 1.21%     Total 0/659 (0%)       Mean 0%      SD 0%        |
 __________________________________________________________________________________________________________________________________
|#Lymph Node, Mesenteric:                                                                                                          |
|   Sarcoma                              0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/100(0%)     1/60 (2%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 0/659 (0%)      Mean 0%      SD 0%        Total 1/659 (0.15%)    Mean 0.15%   SD 0.5%      |
 __________________________________________________________________________________________________________________________________
|#Lymph Node:                                                                                                                      |
|   Sarcoma                              0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     1/50 (2%)                   |
| Overall Incidence               Total 0/659 (0%)      Mean 0%      SD 0%        Total 1/659 (0.15%)    Mean 0.18%   SD 0.6%      |
 __________________________________________________________________________________________________________________________________
|#Mammary Gland:                                                                                                                   |
|   Carcinoma                            0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           1/50 (2%)     1/100(1%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 0/659 (0%)      Mean 0%      SD 0%        Total 2/659 (0.3%)     Mean 0.27%   SD 0.65%     |
 __________________________________________________________________________________________________________________________________
|#Mammary Gland:                                                                                                                   |
|   Carcinoma or Adenoma                 0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           1/50 (2%)     1/100(1%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 0/659 (0%)      Mean 0%      SD 0%        Total 2/659 (0.3%)     Mean 0.27%   SD 0.65%     |
 __________________________________________________________________________________________________________________________________

 *: Denominator is number of animals with tissues examined microscopically
 #: Denominator is number of animals necropsied
                                                 Toxicology Data Management System                                     Page: 14
 Version: 12/20/00                       Tumor Incidence for Selected Control Animal Groups

 Contract/Lab: All Laboratories                          Route: VARIOUS                                    Date of
 Species: MICE                                           Vehicle: NTP 2000 DIET                            Input File: 20-DEC-2000
 Strain: B6C3F1
 Length of Study: CHRONIC                   
                                             Incidence Data for Vehicle Control Groups
 __________________________________________________________________________________________________________________________________
|                                                   Male                                              Female                       |
 __________________________________________________________________________________________________________________________________
|#Mammary Gland:                                                                                                                   |
|   Fibroma, Fibroadenoma, Carcinoma,    0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|      or Adenoma                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           1/50 (2%)     1/100(1%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 0/659 (0%)      Mean 0%      SD 0%        Total 2/659 (0.3%)     Mean 0.27%   SD 0.65%     |
 __________________________________________________________________________________________________________________________________
|#Mesentery:                                                                                                                       |
|   Hemangiosarcoma                      0/50 (0%)     0/100(0%)     0/49 (0%)           1/50 (2%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 0/659 (0%)      Mean 0%      SD 0%        Total 1/659 (0.15%)    Mean 0.18%   SD 0.6%      |
 __________________________________________________________________________________________________________________________________
|#Mesentery:                                                                                                                       |
|   Sarcoma                              1/50 (2%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     1/50 (2%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     1/100(1%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     1/50 (2%)                   |
| Overall Incidence               Total 1/659 (0.15%)   Mean 0.18%   SD 0.6%      Total 3/659 (0.46%)    Mean 0.45%   SD 0.82%     |
 __________________________________________________________________________________________________________________________________
|#Mesentery:                                                                                                                       |
|   Sarcoma NOS                          0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     1/50 (2%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 0/659 (0%)      Mean 0%      SD 0%        Total 1/659 (0.15%)    Mean 0.18%   SD 0.6%      |
 __________________________________________________________________________________________________________________________________
|#Oral Cavity (Oral Mucosa, Tongue,                                                                                                |
| Pharynx, Tooth, Gingiva):                                                                                                        |
|   Papilloma Squamous or Papilloma      0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     1/50 (2%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        1/50 (2%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 1/659 (0.15%)   Mean 0.18%   SD 0.6%      Total 1/659 (0.15%)    Mean 0.18%   SD 0.6%      |
 __________________________________________________________________________________________________________________________________
|#Oral Cavity (Oral Mucosa, Tongue,                                                                                                |
| Pharynx, Tooth, Gingiva):                                                                                                        |
|   Squamous Cell Carcinoma              0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     1/99 (1%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 0/659 (0%)      Mean 0%      SD 0%        Total 1/659 (0.15%)    Mean 0.09%   SD 0.3%      |
 __________________________________________________________________________________________________________________________________
|#Oral Cavity (Oral Mucosa, Tongue,                                                                                                |
| Pharynx, Tooth, Gingiva):                                                                                                        |
|   Squamous Cell Carcinoma,             0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     1/99 (1%)     1/50 (2%)     |
|      Papilloma Squamous, or Papilloma  0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        1/50 (2%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 1/659 (0.15%)   Mean 0.18%   SD 0.6%      Total 2/659 (0.3%)     Mean 0.27%   SD 0.65%     |
 __________________________________________________________________________________________________________________________________

 *: Denominator is number of animals with tissues examined microscopically
 #: Denominator is number of animals necropsied
                                                 Toxicology Data Management System                                     Page: 15
 Version: 12/20/00                       Tumor Incidence for Selected Control Animal Groups

 Contract/Lab: All Laboratories                          Route: VARIOUS                                    Date of
 Species: MICE                                           Vehicle: NTP 2000 DIET                            Input File: 20-DEC-2000
 Strain: B6C3F1
 Length of Study: CHRONIC                   
                                             Incidence Data for Vehicle Control Groups
 __________________________________________________________________________________________________________________________________
|                                                   Male                                              Female                       |
 __________________________________________________________________________________________________________________________________
|#Oral Mucosa:                                                                                                                     |
|   Squamous Cell Papilloma              0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     1/50 (2%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 0/659 (0%)      Mean 0%      SD 0%        Total 1/659 (0.15%)    Mean 0.18%   SD 0.6%      |
 __________________________________________________________________________________________________________________________________
|*Ovary:                                                                                                                           |
|   Cystadenoma                                                                          8/50 (16%)    3/99 (3%)     2/50 (4%)     |
|                                                                                        2/50 (4%)     0/47 (0%)     0/47 (0%)     |
|                                                                                        1/48 (2%)     3/79 (4%)     1/59 (2%)     |
|                                                                                        3/48 (6%)     1/49 (2%)                   |
| Overall Incidence                                                               Total 24/626 (3.83%)   Mean 3.9%    SD 4.41%     |
 __________________________________________________________________________________________________________________________________
|*Ovary:                                                                                                                           |
|   Granulosa Cell Tumor Benign                                                          0/50 (0%)     1/99 (1%)     0/50 (0%)     |
|                                                                                        1/50 (2%)     0/47 (0%)     0/47 (0%)     |
|                                                                                        0/48 (0%)     2/79 (3%)     0/59 (0%)     |
|                                                                                        1/48 (2%)     0/49 (0%)                   |
| Overall Incidence                                                               Total 5/626 (0.8%)     Mean 0.69%   SD 1.02%     |
 __________________________________________________________________________________________________________________________________
|*Ovary:                                                                                                                           |
|   Granulosa Cell Tumor: Benign,                                                        0/50 (0%)     1/99 (1%)     0/50 (0%)     |
|      Malignant, NOS                                                                    1/50 (2%)     0/47 (0%)     0/47 (0%)     |
|                                                                                        0/48 (0%)     2/79 (3%)     0/59 (0%)     |
|                                                                                        1/48 (2%)     0/49 (0%)                   |
| Overall Incidence                                                               Total 5/626 (0.8%)     Mean 0.69%   SD 1.02%     |
 __________________________________________________________________________________________________________________________________
|*Ovary:                                                                                                                           |
|   Hemangioma                                                                           0/50 (0%)     0/99 (0%)     2/50 (4%)     |
|                                                                                        0/50 (0%)     0/47 (0%)     0/47 (0%)     |
|                                                                                        0/48 (0%)     0/79 (0%)     0/59 (0%)     |
|                                                                                        1/48 (2%)     0/49 (0%)                   |
| Overall Incidence                                                               Total 3/626 (0.48%)    Mean 0.55%   SD 1.3%      |
 __________________________________________________________________________________________________________________________________
|*Ovary:                                                                                                                           |
|   Hemangiosarcoma                                                                      0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                                                                        0/50 (0%)     0/47 (0%)     0/47 (0%)     |
|                                                                                        0/48 (0%)     1/79 (1%)     0/59 (0%)     |
|                                                                                        0/48 (0%)     0/49 (0%)                   |
| Overall Incidence                                                               Total 1/626 (0.16%)    Mean 0.12%   SD 0.38%     |
 __________________________________________________________________________________________________________________________________
|*Ovary:                                                                                                                           |
|   Luteoma                                                                              0/50 (0%)     1/99 (1%)     0/50 (0%)     |
|                                                                                        0/50 (0%)     0/47 (0%)     0/47 (0%)     |
|                                                                                        0/48 (0%)     1/79 (1%)     2/59 (3%)     |
|                                                                                        0/48 (0%)     0/49 (0%)                   |
| Overall Incidence                                                               Total 4/626 (0.64%)    Mean 0.52%   SD 1.06%     |
 __________________________________________________________________________________________________________________________________

 *: Denominator is number of animals with tissues examined microscopically
 #: Denominator is number of animals necropsied
                                                 Toxicology Data Management System                                     Page: 16
 Version: 12/20/00                       Tumor Incidence for Selected Control Animal Groups

 Contract/Lab: All Laboratories                          Route: VARIOUS                                    Date of
 Species: MICE                                           Vehicle: NTP 2000 DIET                            Input File: 20-DEC-2000
 Strain: B6C3F1
 Length of Study: CHRONIC                   
                                             Incidence Data for Vehicle Control Groups
 __________________________________________________________________________________________________________________________________
|                                                   Male                                              Female                       |
 __________________________________________________________________________________________________________________________________
|*Ovary:                                                                                                                           |
|   Teratoma Benign                                                                      0/50 (0%)     0/99 (0%)     1/50 (2%)     |
|                                                                                        0/50 (0%)     0/47 (0%)     0/47 (0%)     |
|                                                                                        0/48 (0%)     0/79 (0%)     0/59 (0%)     |
|                                                                                        0/48 (0%)     0/49 (0%)                   |
| Overall Incidence                                                               Total 1/626 (0.16%)    Mean 0.18%   SD 0.6%      |
 __________________________________________________________________________________________________________________________________
|*Pancreas:                                                                                                                        |
|   Sarcoma                              0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/49 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/99 (0%)     0/59 (0%)           0/50 (0%)     0/87 (0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/49 (0%)                         0/49 (0%)     1/49 (2%)                   |
| Overall Incidence               Total 0/655 (0%)      Mean 0%      SD 0%        Total 1/644 (0.16%)    Mean 0.19%   SD 0.62%     |
 __________________________________________________________________________________________________________________________________
|*Pituitary Gland: Pars Distalis or                                                                                                |
| Unspecified Site                       0/49 (0%)     0/98 (0%)     0/48 (0%)           2/48 (4%)     8/97 (8%)     2/49 (4%)     |
|   Adenoma                              0/49 (0%)     0/49 (0%)     0/48 (0%)           3/48 (6%)     1/48 (2%)    10/50 (20%)    |
|                                        1/50 (2%)     0/83 (0%)     1/53 (2%)           8/49 (16%)   17/83 (20%)    3/58 (5%)     |
|                                        0/46 (0%)     1/49 (2%)                         0/45 (0%)     5/48 (10%)                  |
| Overall Incidence               Total 3/622 (0.48%)   Mean 0.54%   SD 0.92%     Total 59/623 (9.47%)   Mean 8.84%   SD 7.12%     |
 __________________________________________________________________________________________________________________________________
|*Pituitary Gland: Pars Distalis or                                                                                                |
| Unspecified Site                       0/49 (0%)     0/98 (0%)     0/48 (0%)           0/48 (0%)     0/97 (0%)     0/49 (0%)     |
|   Carcinoma                            0/49 (0%)     0/49 (0%)     0/48 (0%)           0/48 (0%)     0/48 (0%)     0/50 (0%)     |
|                                        1/50 (2%)     0/83 (0%)     0/53 (0%)           0/49 (0%)     0/83 (0%)     0/58 (0%)     |
|                                        0/46 (0%)     0/49 (0%)                         0/45 (0%)     0/48 (0%)                   |
| Overall Incidence               Total 1/622 (0.16%)   Mean 0.18%   SD 0.6%      Total 0/623 (0%)       Mean 0%      SD 0%        |
 __________________________________________________________________________________________________________________________________
|*Pituitary Gland: Pars Distalis or                                                                                                |
| Unspecified Site                       0/49 (0%)     0/98 (0%)     0/48 (0%)           2/48 (4%)     8/97 (8%)     2/49 (4%)     |
|   Carcinoma or Adenoma                 0/49 (0%)     0/49 (0%)     0/48 (0%)           3/48 (6%)     1/48 (2%)    10/50 (20%)    |
|                                        2/50 (4%)     0/83 (0%)     1/53 (2%)           8/49 (16%)   17/83 (20%)    3/58 (5%)     |
|                                        0/46 (0%)     1/49 (2%)                         0/45 (0%)     5/48 (10%)                  |
| Overall Incidence               Total 4/622 (0.64%)   Mean 0.72%   SD 1.34%     Total 59/623 (9.47%)   Mean 8.84%   SD 7.12%     |
 __________________________________________________________________________________________________________________________________
|*Pituitary Gland: Pars Intermedia                                                                                                 |
|   Adenoma                              1/49 (2%)     0/98 (0%)     0/48 (0%)           0/48 (0%)     2/97 (2%)     2/49 (4%)     |
|                                        0/49 (0%)     0/49 (0%)     0/48 (0%)           1/48 (2%)     0/48 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/83 (0%)     0/53 (0%)           0/49 (0%)     1/83 (1%)     0/58 (0%)     |
|                                        0/46 (0%)     0/49 (0%)                         0/45 (0%)     0/48 (0%)                   |
| Overall Incidence               Total 1/622 (0.16%)   Mean 0.19%   SD 0.62%     Total 6/623 (0.96%)    Mean 0.86%   SD 1.36%     |
 __________________________________________________________________________________________________________________________________
|*Pituitary Gland: Pars Intermedia                                                                                                 |
|   Carcinoma or Adenoma                 1/49 (2%)     0/98 (0%)     0/48 (0%)           0/48 (0%)     2/97 (2%)     2/49 (4%)     |
|                                        0/49 (0%)     0/49 (0%)     0/48 (0%)           1/48 (2%)     0/48 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/83 (0%)     0/53 (0%)           0/49 (0%)     1/83 (1%)     0/58 (0%)     |
|                                        0/46 (0%)     0/49 (0%)                         0/45 (0%)     0/48 (0%)                   |
| Overall Incidence               Total 1/622 (0.16%)   Mean 0.19%   SD 0.62%     Total 6/623 (0.96%)    Mean 0.86%   SD 1.36%     |
 __________________________________________________________________________________________________________________________________

 *: Denominator is number of animals with tissues examined microscopically
 #: Denominator is number of animals necropsied
                                                 Toxicology Data Management System                                     Page: 17
 Version: 12/20/00                       Tumor Incidence for Selected Control Animal Groups

 Contract/Lab: All Laboratories                          Route: VARIOUS                                    Date of
 Species: MICE                                           Vehicle: NTP 2000 DIET                            Input File: 20-DEC-2000
 Strain: B6C3F1
 Length of Study: CHRONIC                   
                                             Incidence Data for Vehicle Control Groups
 __________________________________________________________________________________________________________________________________
|                                                   Male                                              Female                       |
 __________________________________________________________________________________________________________________________________
|*Prostate:                                                                                                                        |
|   Hemangiosarcoma                      0/50 (0%)     0/100(0%)     1/49 (2%)                                                     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)                                                     |
|                                        0/50 (0%)     0/98 (0%)     0/60 (0%)                                                     |
|                                        0/50 (0%)     0/50 (0%)                                                                   |
| Overall Incidence               Total 1/657 (0.15%)   Mean 0.19%   SD 0.62%                                                      |
 __________________________________________________________________________________________________________________________________
|*Salivary Glands:                                                                                                                 |
|   Carcinoma                            0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/98 (0%)     0/48 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/49 (0%)     0/49 (0%)     0/49 (0%)     |
|                                        0/50 (0%)     0/99 (0%)     0/60 (0%)           0/50 (0%)     1/94 (1%)     0/59 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 0/658 (0%)      Mean 0%      SD 0%        Total 1/646 (0.15%)    Mean 0.1%    SD 0.32%     |
 __________________________________________________________________________________________________________________________________
|*Salivary Glands:                                                                                                                 |
|   Carcinoma or Adenoma                 0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/98 (0%)     0/48 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/49 (0%)     0/49 (0%)     0/49 (0%)     |
|                                        0/50 (0%)     0/99 (0%)     0/60 (0%)           0/50 (0%)     1/94 (1%)     0/59 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 0/658 (0%)      Mean 0%      SD 0%        Total 1/646 (0.15%)    Mean 0.1%    SD 0.32%     |
 __________________________________________________________________________________________________________________________________
|#Seminal Vesicle:                                                                                                                 |
|   Adenoma                              0/50 (0%)     0/100(0%)     0/49 (0%)                                                     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)                                                     |
|                                        1/50 (2%)     0/100(0%)     0/60 (0%)                                                     |
|                                        0/50 (0%)     0/50 (0%)                                                                   |
| Overall Incidence               Total 1/659 (0.15%)   Mean 0.18%   SD 0.6%                                                       |
 __________________________________________________________________________________________________________________________________
|#Seminal Vesicle:                                                                                                                 |
|   Carcinoma                            1/50 (2%)     0/100(0%)     0/49 (0%)                                                     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)                                                     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)                                                     |
|                                        0/50 (0%)     0/50 (0%)                                                                   |
| Overall Incidence               Total 1/659 (0.15%)   Mean 0.18%   SD 0.6%                                                       |
 __________________________________________________________________________________________________________________________________
|#Skeletal Muscle:                                                                                                                 |
|   Hemangioma                           0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/100(0%)     1/60 (2%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 0/659 (0%)      Mean 0%      SD 0%        Total 1/659 (0.15%)    Mean 0.15%   SD 0.5%      |
 __________________________________________________________________________________________________________________________________
|#Skeletal Muscle:                                                                                                                 |
|   Rhabdomyosarcoma                     0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     3/100(3%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 0/659 (0%)      Mean 0%      SD 0%        Total 3/659 (0.46%)    Mean 0.27%   SD 0.9%      |
 __________________________________________________________________________________________________________________________________

 *: Denominator is number of animals with tissues examined microscopically
 #: Denominator is number of animals necropsied
                                                 Toxicology Data Management System                                     Page: 18
 Version: 12/20/00                       Tumor Incidence for Selected Control Animal Groups

 Contract/Lab: All Laboratories                          Route: VARIOUS                                    Date of
 Species: MICE                                           Vehicle: NTP 2000 DIET                            Input File: 20-DEC-2000
 Strain: B6C3F1
 Length of Study: CHRONIC                   
                                             Incidence Data for Vehicle Control Groups
 __________________________________________________________________________________________________________________________________
|                                                   Male                                              Female                       |
 __________________________________________________________________________________________________________________________________
|#Skeletal Muscle:                                                                                                                 |
|   Rhabdomyosarcoma or Rhabdomyoma      0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     3/100(3%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 0/659 (0%)      Mean 0%      SD 0%        Total 3/659 (0.46%)    Mean 0.27%   SD 0.9%      |
 __________________________________________________________________________________________________________________________________
|#Skeletal Muscle:                                                                                                                 |
|   Sarcoma                              0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     1/99 (1%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     1/50 (2%)                   |
| Overall Incidence               Total 0/659 (0%)      Mean 0%      SD 0%        Total 2/659 (0.3%)     Mean 0.27%   SD 0.65%     |
 __________________________________________________________________________________________________________________________________
|#Skin:                                                                                                                            |
|   Basal Cell Carcinoma                 0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     1/100(1%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 0/659 (0%)      Mean 0%      SD 0%        Total 1/659 (0.15%)    Mean 0.09%   SD 0.3%      |
 __________________________________________________________________________________________________________________________________
|#Skin:                                                                                                                            |
|   Basal Cell Carcinoma or              0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|      Basosquamous Tumor (malignant or  0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|      NOS)                              0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     1/100(1%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 0/659 (0%)      Mean 0%      SD 0%        Total 1/659 (0.15%)    Mean 0.09%   SD 0.3%      |
 __________________________________________________________________________________________________________________________________
|#Skin:                                                                                                                            |
|   Basal Cell Carcinoma, Basal Cell     0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|      Adenoma, Basosquamous Tumor       0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|      (benign, malignant or NOS), or    0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     1/100(1%)     0/60 (0%)     |
|      Trichoepithelioma                 0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 0/659 (0%)      Mean 0%      SD 0%        Total 1/659 (0.15%)    Mean 0.09%   SD 0.3%      |
 __________________________________________________________________________________________________________________________________
|#Skin:                                                                                                                            |
|   Basal or Sq. Cell Carcinoma,         0/50 (0%)     0/100(0%)     1/49 (2%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|      Carcinoma, Basosq. Tumor (M or    0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|      B), Basal Cell Adenoma, Adenoma,  0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     1/100(1%)     0/60 (0%)     |
|      Papilloma, Sq Papilloma,          1/50 (2%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
|      Keratoacanthoma,                                                                                                            |
|      Trichoepithelioma                                                                                                           |
| Overall Incidence               Total 2/659 (0.3%)    Mean 0.37%   SD 0.82%     Total 1/659 (0.15%)    Mean 0.09%   SD 0.3%      |
 __________________________________________________________________________________________________________________________________
|#Skin:                                                                                                                            |
|   Hemangioma                           0/50 (0%)     1/100(1%)     0/49 (0%)           0/50 (0%)     1/99 (1%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     1/50 (2%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 1/659 (0.15%)   Mean 0.09%   SD 0.3%      Total 2/659 (0.3%)     Mean 0.27%   SD 0.65%     |
 __________________________________________________________________________________________________________________________________

 *: Denominator is number of animals with tissues examined microscopically
 #: Denominator is number of animals necropsied
                                                 Toxicology Data Management System                                     Page: 19
 Version: 12/20/00                       Tumor Incidence for Selected Control Animal Groups

 Contract/Lab: All Laboratories                          Route: VARIOUS                                    Date of
 Species: MICE                                           Vehicle: NTP 2000 DIET                            Input File: 20-DEC-2000
 Strain: B6C3F1
 Length of Study: CHRONIC                   
                                             Incidence Data for Vehicle Control Groups
 __________________________________________________________________________________________________________________________________
|                                                   Male                                              Female                       |
 __________________________________________________________________________________________________________________________________
|#Skin:                                                                                                                            |
|   Hemangiosarcoma                      1/50 (2%)     0/100(0%)     0/49 (0%)           1/50 (2%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     1/50 (2%)     0/50 (0%)           0/50 (0%)     1/50 (2%)     2/50 (4%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           1/50 (2%)     0/100(0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         1/50 (2%)     0/50 (0%)                   |
| Overall Incidence               Total 2/659 (0.3%)    Mean 0.36%   SD 0.81%     Total 6/659 (0.91%)    Mean 1.09%   SD 1.38%     |
 __________________________________________________________________________________________________________________________________
|#Skin:                                                                                                                            |
|   Keratoacanthoma                      0/50 (0%)     0/100(0%)     1/49 (2%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 1/659 (0.15%)   Mean 0.19%   SD 0.62%     Total 0/659 (0%)       Mean 0%      SD 0%        |
 __________________________________________________________________________________________________________________________________
|#Skin:                                                                                                                            |
|   Lipoma                               0/50 (0%)     0/100(0%)     1/49 (2%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         1/50 (2%)     0/50 (0%)                   |
| Overall Incidence               Total 1/659 (0.15%)   Mean 0.19%   SD 0.62%     Total 1/659 (0.15%)    Mean 0.18%   SD 0.6%      |
 __________________________________________________________________________________________________________________________________
|#Skin:                                                                                                                            |
|   Mast Cell Tumor Malignant            0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        1/50 (2%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 1/659 (0.15%)   Mean 0.18%   SD 0.6%      Total 0/659 (0%)       Mean 0%      SD 0%        |
 __________________________________________________________________________________________________________________________________
|#Skin:                                                                                                                            |
|   Squamous Cell Carcinoma, Basal       0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|      Cell Carcinoma, Basosquamous      0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|      Tumor (malignant or NOS), or      0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     1/100(1%)     0/60 (0%)     |
|      Carcinoma                         0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 0/659 (0%)      Mean 0%      SD 0%        Total 1/659 (0.15%)    Mean 0.09%   SD 0.3%      |
 __________________________________________________________________________________________________________________________________
|#Skin:                                                                                                                            |
|   Squamous Cell Papilloma              0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                        1/50 (2%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 1/659 (0.15%)   Mean 0.18%   SD 0.6%      Total 0/659 (0%)       Mean 0%      SD 0%        |
 __________________________________________________________________________________________________________________________________
|#Skin:                                                                                                                            |
|   Squamous Cell Papilloma or           0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|      Papilloma                         0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                        1/50 (2%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 1/659 (0.15%)   Mean 0.18%   SD 0.6%      Total 0/659 (0%)       Mean 0%      SD 0%        |
 __________________________________________________________________________________________________________________________________

 *: Denominator is number of animals with tissues examined microscopically
 #: Denominator is number of animals necropsied
                                                 Toxicology Data Management System                                     Page: 20
 Version: 12/20/00                       Tumor Incidence for Selected Control Animal Groups

 Contract/Lab: All Laboratories                          Route: VARIOUS                                    Date of
 Species: MICE                                           Vehicle: NTP 2000 DIET                            Input File: 20-DEC-2000
 Strain: B6C3F1
 Length of Study: CHRONIC                   
                                             Incidence Data for Vehicle Control Groups
 __________________________________________________________________________________________________________________________________
|                                                   Male                                              Female                       |
 __________________________________________________________________________________________________________________________________
|#Skin:                                                                                                                            |
|   Squamous Cell Papilloma,             0/50 (0%)     0/100(0%)     1/49 (2%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|      Papilloma, Squamous Cell          0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|      Carcinoma or Keratoacanthoma      0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                        1/50 (2%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 2/659 (0.3%)    Mean 0.37%   SD 0.82%     Total 0/659 (0%)       Mean 0%      SD 0%        |
 __________________________________________________________________________________________________________________________________
|#Skin:                                                                                                                            |
|   Squamous Cell Papilloma,             0/50 (0%)     0/100(0%)     1/49 (2%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|      Papilloma, or Keratoacanthoma     0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                        1/50 (2%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 2/659 (0.3%)    Mean 0.37%   SD 0.82%     Total 0/659 (0%)       Mean 0%      SD 0%        |
 __________________________________________________________________________________________________________________________________
|#Skin:                                                                                                                            |
|   Fibroma, Fibrosarcoma, Sarcoma,      0/50 (0%)     1/100(1%)     0/49 (0%)           3/50 (6%)     2/99 (2%)     2/50 (4%)     |
|      Myxoma, Myxosarcoma, or Fibrous   0/50 (0%)     0/50 (0%)     0/50 (0%)           1/50 (2%)     1/50 (2%)     0/50 (0%)     |
|      Histiocytoma                      0/50 (0%)     0/100(0%)     0/60 (0%)           2/50 (4%)     4/100(4%)     1/60 (2%)     |
|                                        0/50 (0%)     0/50 (0%)                         2/50 (4%)     3/50 (6%)                   |
| Overall Incidence               Total 1/659 (0.15%)   Mean 0.09%   SD 0.3%      Total 21/659 (3.19%)   Mean 3.24%   SD 1.87%     |
 __________________________________________________________________________________________________________________________________
|#Skin:                                                                                                                            |
|   Fibrosarcoma                         0/50 (0%)     1/100(1%)     0/49 (0%)           2/50 (4%)     0/99 (0%)     2/50 (4%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         1/50 (2%)     0/50 (0%)                   |
| Overall Incidence               Total 1/659 (0.15%)   Mean 0.09%   SD 0.3%      Total 5/659 (0.76%)    Mean 0.91%   SD 1.64%     |
 __________________________________________________________________________________________________________________________________
|#Skin:                                                                                                                            |
|   Fibrosarcoma, Sarcoma,               0/50 (0%)     1/100(1%)     0/49 (0%)           3/50 (6%)     2/99 (2%)     2/50 (4%)     |
|      Myxosarcoma, or Fibrous           0/50 (0%)     0/50 (0%)     0/50 (0%)           1/50 (2%)     1/50 (2%)     0/50 (0%)     |
|      Histiocytoma                      0/50 (0%)     0/100(0%)     0/60 (0%)           2/50 (4%)     4/100(4%)     1/60 (2%)     |
|                                        0/50 (0%)     0/50 (0%)                         2/50 (4%)     3/50 (6%)                   |
| Overall Incidence               Total 1/659 (0.15%)   Mean 0.09%   SD 0.3%      Total 21/659 (3.19%)   Mean 3.24%   SD 1.87%     |
 __________________________________________________________________________________________________________________________________
|#Skin:                                                                                                                            |
|   Myxosarcoma                          0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           1/50 (2%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 0/659 (0%)      Mean 0%      SD 0%        Total 1/659 (0.15%)    Mean 0.18%   SD 0.6%      |
 __________________________________________________________________________________________________________________________________
|#Skin:                                                                                                                            |
|   Neurofibrosarcoma or Schwannoma      0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     2/50 (4%)     |
|      (malignant or NOS)                0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     2/100(2%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 0/659 (0%)      Mean 0%      SD 0%        Total 4/659 (0.61%)    Mean 0.55%   SD 1.29%     |
 __________________________________________________________________________________________________________________________________

 *: Denominator is number of animals with tissues examined microscopically
 #: Denominator is number of animals necropsied
                                                 Toxicology Data Management System                                     Page: 21
 Version: 12/20/00                       Tumor Incidence for Selected Control Animal Groups

 Contract/Lab: All Laboratories                          Route: VARIOUS                                    Date of
 Species: MICE                                           Vehicle: NTP 2000 DIET                            Input File: 20-DEC-2000
 Strain: B6C3F1
 Length of Study: CHRONIC                   
                                             Incidence Data for Vehicle Control Groups
 __________________________________________________________________________________________________________________________________
|                                                   Male                                              Female                       |
 __________________________________________________________________________________________________________________________________
|#Skin:                                                                                                                            |
|   Neurofibrosarcoma, Neurofibroma,     0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     2/50 (4%)     |
|      or Schwannoma (benign, malignant  0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|      or NOS)                           0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     2/100(2%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 0/659 (0%)      Mean 0%      SD 0%        Total 4/659 (0.61%)    Mean 0.55%   SD 1.29%     |
 __________________________________________________________________________________________________________________________________
|#Skin:                                                                                                                            |
|   Sarcoma                              0/50 (0%)     0/100(0%)     0/49 (0%)           1/50 (2%)     2/99 (2%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     1/50 (2%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           2/50 (4%)     4/100(4%)     1/60 (2%)     |
|                                        0/50 (0%)     0/50 (0%)                         1/50 (2%)     3/50 (6%)                   |
| Overall Incidence               Total 0/659 (0%)      Mean 0%      SD 0%        Total 15/659 (2.28%)   Mean 2.15%   SD 1.89%     |
 __________________________________________________________________________________________________________________________________
|#Skin:                                                                                                                            |
|   Schwannoma Malignant                 0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     2/50 (4%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     2/100(2%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 0/659 (0%)      Mean 0%      SD 0%        Total 4/659 (0.61%)    Mean 0.55%   SD 1.29%     |
 __________________________________________________________________________________________________________________________________
|*Spleen:                                                                                                                          |
|   Hemangioma                           0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/49 (0%)     0/49 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/99 (0%)     1/60 (2%)           0/50 (0%)     0/91 (0%)     0/59 (0%)     |
|                                        0/50 (0%)     0/49 (0%)                         0/49 (0%)     0/49 (0%)                   |
| Overall Incidence               Total 1/657 (0.15%)   Mean 0.15%   SD 0.5%      Total 0/645 (0%)       Mean 0%      SD 0%        |
 __________________________________________________________________________________________________________________________________
|*Spleen:                                                                                                                          |
|   Hemangiosarcoma                      1/50 (2%)     0/100(0%)     1/49 (2%)           0/50 (0%)     0/99 (0%)     1/50 (2%)     |
|                                        1/50 (2%)     3/50 (6%)     2/50 (4%)           0/49 (0%)     0/49 (0%)     1/50 (2%)     |
|                                        0/50 (0%)     2/99 (2%)     2/60 (3%)           2/50 (4%)     0/91 (0%)     0/59 (0%)     |
|                                        0/50 (0%)     1/49 (2%)                         0/49 (0%)     0/49 (0%)                   |
| Overall Incidence               Total 13/657 (1.98%)  Mean 2.13%   SD 1.83%     Total 4/645 (0.62%)    Mean 0.73%   SD 1.35%     |
 __________________________________________________________________________________________________________________________________
|*Spleen:                                                                                                                          |
|   Mast Cell Tumor Malignant            0/50 (0%)     1/100(1%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/49 (0%)     0/49 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/99 (0%)     0/60 (0%)           0/50 (0%)     0/91 (0%)     0/59 (0%)     |
|                                        0/50 (0%)     0/49 (0%)                         0/49 (0%)     0/49 (0%)                   |
| Overall Incidence               Total 1/657 (0.15%)   Mean 0.09%   SD 0.3%      Total 0/645 (0%)       Mean 0%      SD 0%        |
 __________________________________________________________________________________________________________________________________
|*Spleen:                                                                                                                          |
|   Plasma Cell Tumor Malignant          0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/49 (0%)     0/49 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/99 (0%)     0/60 (0%)           0/50 (0%)     1/91 (1%)     0/59 (0%)     |
|                                        0/50 (0%)     0/49 (0%)                         0/49 (0%)     0/49 (0%)                   |
| Overall Incidence               Total 0/657 (0%)      Mean 0%      SD 0%        Total 1/645 (0.16%)    Mean 0.1%    SD 0.33%     |
 __________________________________________________________________________________________________________________________________

 *: Denominator is number of animals with tissues examined microscopically
 #: Denominator is number of animals necropsied
                                                 Toxicology Data Management System                                     Page: 22
 Version: 12/20/00                       Tumor Incidence for Selected Control Animal Groups

 Contract/Lab: All Laboratories                          Route: VARIOUS                                    Date of
 Species: MICE                                           Vehicle: NTP 2000 DIET                            Input File: 20-DEC-2000
 Strain: B6C3F1
 Length of Study: CHRONIC                   
                                             Incidence Data for Vehicle Control Groups
 __________________________________________________________________________________________________________________________________
|                                                   Male                                              Female                       |
 __________________________________________________________________________________________________________________________________
|#Stomach, Forestomach:                                                                                                            |
|   Hemangioma                           0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/100(0%)     1/60 (2%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 0/659 (0%)      Mean 0%      SD 0%        Total 1/659 (0.15%)    Mean 0.15%   SD 0.5%      |
 __________________________________________________________________________________________________________________________________
|#Stomach, Forestomach:                                                                                                            |
|   Squamous Cell Carcinoma              0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     1/50 (2%)           0/50 (0%)     0/50 (0%)     1/50 (2%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 1/659 (0.15%)   Mean 0.18%   SD 0.6%      Total 1/659 (0.15%)    Mean 0.18%   SD 0.6%      |
 __________________________________________________________________________________________________________________________________
|#Stomach, Forestomach:                                                                                                            |
|   Squamous Cell Carcinoma or           3/50 (6%)     0/100(0%)     1/49 (2%)           3/50 (6%)     1/99 (1%)     0/50 (0%)     |
|      Papilloma Squamous                0/50 (0%)     1/50 (2%)     2/50 (4%)           0/50 (0%)     1/50 (2%)     1/50 (2%)     |
|                                        2/50 (4%)     0/100(0%)     0/60 (0%)           2/50 (4%)     1/100(1%)     1/60 (2%)     |
|                                        1/50 (2%)     1/50 (2%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 11/659 (1.67%)  Mean 2%      SD 2%        Total 10/659 (1.52%)   Mean 1.61%   SD 1.91%     |
 __________________________________________________________________________________________________________________________________
|#Stomach, Forestomach:                                                                                                            |
|   Squamous Cell Papilloma              3/50 (6%)     0/100(0%)     1/49 (2%)           3/50 (6%)     1/99 (1%)     0/50 (0%)     |
|                                        0/50 (0%)     1/50 (2%)     1/50 (2%)           0/50 (0%)     1/50 (2%)     0/50 (0%)     |
|                                        2/50 (4%)     0/100(0%)     0/60 (0%)           2/50 (4%)     1/100(1%)     1/60 (2%)     |
|                                        1/50 (2%)     1/50 (2%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 10/659 (1.52%)  Mean 1.82%   SD 1.89%     Total 9/659 (1.37%)    Mean 1.43%   SD 1.96%     |
 __________________________________________________________________________________________________________________________________
|*Testes:                                                                                                                          |
|   Adenoma                              0/50 (0%)     1/100(1%)     0/49 (0%)                                                     |
|                                        1/50 (2%)     0/50 (0%)     2/50 (4%)                                                     |
|                                        0/50 (0%)     1/99 (1%)     0/60 (0%)                                                     |
|                                        0/50 (0%)     0/50 (0%)                                                                   |
| Overall Incidence               Total 5/658 (0.76%)   Mean 0.73%   SD 1.27%                                                      |
 __________________________________________________________________________________________________________________________________
|*Testes:                                                                                                                          |
|   Hemangioma                           0/50 (0%)     1/100(1%)     0/49 (0%)                                                     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)                                                     |
|                                        0/50 (0%)     0/99 (0%)     0/60 (0%)                                                     |
|                                        0/50 (0%)     0/50 (0%)                                                                   |
| Overall Incidence               Total 1/658 (0.15%)   Mean 0.09%   SD 0.3%                                                       |
 __________________________________________________________________________________________________________________________________
|*Thymus:                                                                                                                          |
|   Thymoma Benign                       0/47 (0%)     0/99 (0%)     0/40 (0%)           0/50 (0%)     0/95 (0%)     0/47 (0%)     |
|                                        0/45 (0%)     0/37 (0%)     0/35 (0%)           0/49 (0%)     1/46 (2%)     0/47 (0%)     |
|                                        0/35 (0%)     0/69 (0%)     0/57 (0%)           0/44 (0%)     1/78 (1%)     0/57 (0%)     |
|                                        0/47 (0%)     0/42 (0%)                         0/48 (0%)     0/49 (0%)                   |
| Overall Incidence               Total 0/553 (0%)      Mean 0%      SD 0%        Total 2/610 (0.33%)    Mean 0.31%   SD 0.73%     |
 __________________________________________________________________________________________________________________________________

 *: Denominator is number of animals with tissues examined microscopically
 #: Denominator is number of animals necropsied
                                                 Toxicology Data Management System                                     Page: 23
 Version: 12/20/00                       Tumor Incidence for Selected Control Animal Groups

 Contract/Lab: All Laboratories                          Route: VARIOUS                                    Date of
 Species: MICE                                           Vehicle: NTP 2000 DIET                            Input File: 20-DEC-2000
 Strain: B6C3F1
 Length of Study: CHRONIC                   
                                             Incidence Data for Vehicle Control Groups
 __________________________________________________________________________________________________________________________________
|                                                   Male                                              Female                       |
 __________________________________________________________________________________________________________________________________
|*Thymus:                                                                                                                          |
|   Thymoma: Benign, Malignant, NOS      0/47 (0%)     0/99 (0%)     0/40 (0%)           0/50 (0%)     0/95 (0%)     0/47 (0%)     |
|                                        0/45 (0%)     0/37 (0%)     0/35 (0%)           0/49 (0%)     1/46 (2%)     0/47 (0%)     |
|                                        0/35 (0%)     0/69 (0%)     0/57 (0%)           0/44 (0%)     1/78 (1%)     0/57 (0%)     |
|                                        0/47 (0%)     0/42 (0%)                         0/48 (0%)     0/49 (0%)                   |
| Overall Incidence               Total 0/553 (0%)      Mean 0%      SD 0%        Total 2/610 (0.33%)    Mean 0.31%   SD 0.73%     |
 __________________________________________________________________________________________________________________________________
|*Thyroid Gland:                                                                                                                   |
|   Adenoma                              0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/97 (0%)     0/49 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/47 (0%)           0/50 (0%)     0/49 (0%)     0/50 (0%)     |
|                                        0/48 (0%)     1/99 (1%)     0/59 (0%)           0/50 (0%)     2/92 (2%)     0/60 (0%)     |
|                                        0/50 (0%)     0/49 (0%)                         0/50 (0%)     0/49 (0%)                   |
| Overall Incidence               Total 1/651 (0.15%)   Mean 0.09%   SD 0.3%      Total 2/646 (0.31%)    Mean 0.2%    SD 0.66%     |
 __________________________________________________________________________________________________________________________________
|*Thyroid Gland: C-Cell                                                                                                            |
|   Carcinoma                            0/50 (0%)     0/100(0%)     1/49 (2%)           0/50 (0%)     0/97 (0%)     0/49 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/47 (0%)           0/50 (0%)     0/49 (0%)     0/50 (0%)     |
|                                        0/48 (0%)     0/99 (0%)     0/59 (0%)           0/50 (0%)     0/92 (0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/49 (0%)                         0/50 (0%)     0/49 (0%)                   |
| Overall Incidence               Total 1/651 (0.15%)   Mean 0.19%   SD 0.62%     Total 0/646 (0%)       Mean 0%      SD 0%        |
 __________________________________________________________________________________________________________________________________
|*Thyroid Gland: C-Cell                                                                                                            |
|   Carcinoma or Adenoma                 0/50 (0%)     0/100(0%)     1/49 (2%)           0/50 (0%)     0/97 (0%)     0/49 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/47 (0%)           0/50 (0%)     0/49 (0%)     0/50 (0%)     |
|                                        0/48 (0%)     0/99 (0%)     0/59 (0%)           0/50 (0%)     0/92 (0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/49 (0%)                         0/50 (0%)     0/49 (0%)                   |
| Overall Incidence               Total 1/651 (0.15%)   Mean 0.19%   SD 0.62%     Total 0/646 (0%)       Mean 0%      SD 0%        |
 __________________________________________________________________________________________________________________________________
|*Thyroid Gland: Follicular Cell                                                                                                   |
|   Adenoma                              0/50 (0%)     1/100(1%)     0/49 (0%)           2/50 (4%)     0/97 (0%)     0/49 (0%)     |
|                                        1/50 (2%)     0/50 (0%)     0/47 (0%)           2/50 (4%)     0/49 (0%)     0/50 (0%)     |
|                                        0/48 (0%)     0/99 (0%)     1/59 (2%)           0/50 (0%)     0/92 (0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/49 (0%)                         0/50 (0%)     0/49 (0%)                   |
| Overall Incidence               Total 3/651 (0.46%)   Mean 0.43%   SD 0.77%     Total 4/646 (0.62%)    Mean 0.73%   SD 1.62%     |
 __________________________________________________________________________________________________________________________________
|*Thyroid Gland: Follicular Cell                                                                                                   |
|   Carcinoma                            0/50 (0%)     0/100(0%)     1/49 (2%)           0/50 (0%)     0/97 (0%)     0/49 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     1/47 (2%)           0/50 (0%)     0/49 (0%)     0/50 (0%)     |
|                                        0/48 (0%)     0/99 (0%)     0/59 (0%)           0/50 (0%)     0/92 (0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/49 (0%)                         0/50 (0%)     0/49 (0%)                   |
| Overall Incidence               Total 2/651 (0.31%)   Mean 0.38%   SD 0.84%     Total 0/646 (0%)       Mean 0%      SD 0%        |
 __________________________________________________________________________________________________________________________________
|*Thyroid Gland: Follicular Cell                                                                                                   |
|   Carcinoma or Adenoma                 0/50 (0%)     1/100(1%)     1/49 (2%)           2/50 (4%)     0/97 (0%)     0/49 (0%)     |
|                                        1/50 (2%)     0/50 (0%)     1/47 (2%)           2/50 (4%)     0/49 (0%)     0/50 (0%)     |
|                                        0/48 (0%)     0/99 (0%)     1/59 (2%)           0/50 (0%)     0/92 (0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/49 (0%)                         0/50 (0%)     0/49 (0%)                   |
| Overall Incidence               Total 5/651 (0.77%)   Mean 0.81%   SD 0.97%     Total 4/646 (0.62%)    Mean 0.73%   SD 1.62%     |
 __________________________________________________________________________________________________________________________________

 *: Denominator is number of animals with tissues examined microscopically
 #: Denominator is number of animals necropsied
                                                 Toxicology Data Management System                                     Page: 24
 Version: 12/20/00                       Tumor Incidence for Selected Control Animal Groups

 Contract/Lab: All Laboratories                          Route: VARIOUS                                    Date of
 Species: MICE                                           Vehicle: NTP 2000 DIET                            Input File: 20-DEC-2000
 Strain: B6C3F1
 Length of Study: CHRONIC                   
                                             Incidence Data for Vehicle Control Groups
 __________________________________________________________________________________________________________________________________
|                                                   Male                                              Female                       |
 __________________________________________________________________________________________________________________________________
|#Tissue NOS:                                                                                                                      |
|   Rhabdomyosarcoma                     0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     1/100(1%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 0/659 (0%)      Mean 0%      SD 0%        Total 1/659 (0.15%)    Mean 0.09%   SD 0.3%      |
 __________________________________________________________________________________________________________________________________
|#Tissue NOS:                                                                                                                      |
|   Sarcoma                              0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     2/60 (3%)           0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 2/659 (0.3%)    Mean 0.3%    SD 1.01%     Total 0/659 (0%)       Mean 0%      SD 0%        |
 __________________________________________________________________________________________________________________________________
|#Tongue:                                                                                                                          |
|   Squamous Cell Carcinoma              0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     1/99 (1%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 0/659 (0%)      Mean 0%      SD 0%        Total 1/659 (0.15%)    Mean 0.09%   SD 0.3%      |
 __________________________________________________________________________________________________________________________________
|#Tongue:                                                                                                                          |
|   Squamous Cell Carcinoma or           0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     1/99 (1%)     0/50 (0%)     |
|      Papilloma Squamous                0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        1/50 (2%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 1/659 (0.15%)   Mean 0.18%   SD 0.6%      Total 1/659 (0.15%)    Mean 0.09%   SD 0.3%      |
 __________________________________________________________________________________________________________________________________
|#Tongue:                                                                                                                          |
|   Squamous Cell Papilloma              0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        1/50 (2%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 1/659 (0.15%)   Mean 0.18%   SD 0.6%      Total 0/659 (0%)       Mean 0%      SD 0%        |
 __________________________________________________________________________________________________________________________________
|#Tooth:                                                                                                                           |
|   Odontoma                             0/50 (0%)     0/100(0%)     1/49 (2%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 1/659 (0.15%)   Mean 0.19%   SD 0.62%     Total 0/659 (0%)       Mean 0%      SD 0%        |
 __________________________________________________________________________________________________________________________________
|*Urinary Bladder:                                                                                                                 |
|   Carcinoma or Papilloma               0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/48 (0%)     |
|                                        1/50 (2%)     0/98 (0%)     0/59 (0%)           0/48 (0%)     0/79 (0%)     0/59 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/49 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 1/656 (0.15%)   Mean 0.18%   SD 0.6%      Total 0/632 (0%)       Mean 0%      SD 0%        |
 __________________________________________________________________________________________________________________________________

 *: Denominator is number of animals with tissues examined microscopically
 #: Denominator is number of animals necropsied
                                                 Toxicology Data Management System                                     Page: 25
 Version: 12/20/00                       Tumor Incidence for Selected Control Animal Groups

 Contract/Lab: All Laboratories                          Route: VARIOUS                                    Date of
 Species: MICE                                           Vehicle: NTP 2000 DIET                            Input File: 20-DEC-2000
 Strain: B6C3F1
 Length of Study: CHRONIC                   
                                             Incidence Data for Vehicle Control Groups
 __________________________________________________________________________________________________________________________________
|                                                   Male                                              Female                       |
 __________________________________________________________________________________________________________________________________
|*Urinary Bladder:                                                                                                                 |
|   Hemangiosarcoma                      0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     1/50 (2%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/48 (0%)     |
|                                        0/50 (0%)     0/98 (0%)     0/59 (0%)           0/48 (0%)     0/79 (0%)     0/59 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/49 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 0/656 (0%)      Mean 0%      SD 0%        Total 1/632 (0.16%)    Mean 0.18%   SD 0.6%      |
 __________________________________________________________________________________________________________________________________
|*Urinary Bladder:                                                                                                                 |
|   Papilloma                            0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/48 (0%)     |
|                                        1/50 (2%)     0/98 (0%)     0/59 (0%)           0/48 (0%)     0/79 (0%)     0/59 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/49 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 1/656 (0.15%)   Mean 0.18%   SD 0.6%      Total 0/632 (0%)       Mean 0%      SD 0%        |
 __________________________________________________________________________________________________________________________________
|*Urinary Bladder:                                                                                                                 |
|   Sarcoma                              0/50 (0%)     0/100(0%)     0/49 (0%)           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/48 (0%)     |
|                                        0/50 (0%)     0/98 (0%)     0/59 (0%)           0/48 (0%)     0/79 (0%)     0/59 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/49 (0%)     1/50 (2%)                   |
| Overall Incidence               Total 0/656 (0%)      Mean 0%      SD 0%        Total 1/632 (0.16%)    Mean 0.18%   SD 0.6%      |
 __________________________________________________________________________________________________________________________________
|#Uterus:                                                                                                                          |
|   Adenoma                                                                              0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                                                                        0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                                                                        0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                                                                        0/50 (0%)     1/50 (2%)                   |
| Overall Incidence                                                               Total 1/659 (0.15%)    Mean 0.18%   SD 0.6%      |
 __________________________________________________________________________________________________________________________________
|#Uterus:                                                                                                                          |
|   Hemangioma                                                                           0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                                                                        0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                                                                        0/50 (0%)     0/100(0%)     1/60 (2%)     |
|                                                                                        0/50 (0%)     0/50 (0%)                   |
| Overall Incidence                                                               Total 1/659 (0.15%)    Mean 0.15%   SD 0.5%      |
 __________________________________________________________________________________________________________________________________
|#Uterus:                                                                                                                          |
|   Hemangiosarcoma                                                                      0/50 (0%)     0/99 (0%)     0/50 (0%)     |
|                                                                                        0/50 (0%)     0/50 (0%)     1/50 (2%)     |
|                                                                                        0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                                                                        0/50 (0%)     0/50 (0%)                   |
| Overall Incidence                                                               Total 1/659 (0.15%)    Mean 0.18%   SD 0.6%      |
 __________________________________________________________________________________________________________________________________
|#Uterus:                                                                                                                          |
|   Leiomyoma                                                                            0/50 (0%)     0/99 (0%)     1/50 (2%)     |
|                                                                                        0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                                                                        0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                                                                        0/50 (0%)     0/50 (0%)                   |
| Overall Incidence                                                               Total 1/659 (0.15%)    Mean 0.18%   SD 0.6%      |
 __________________________________________________________________________________________________________________________________

 *: Denominator is number of animals with tissues examined microscopically
 #: Denominator is number of animals necropsied
                                                 Toxicology Data Management System                                     Page: 26
 Version: 12/20/00                       Tumor Incidence for Selected Control Animal Groups

 Contract/Lab: All Laboratories                          Route: VARIOUS                                    Date of
 Species: MICE                                           Vehicle: NTP 2000 DIET                            Input File: 20-DEC-2000
 Strain: B6C3F1
 Length of Study: CHRONIC                   
                                             Incidence Data for Vehicle Control Groups
 __________________________________________________________________________________________________________________________________
|                                                   Male                                              Female                       |
 __________________________________________________________________________________________________________________________________
|#Uterus:                                                                                                                          |
|   Leiomyosarcoma                                                                       0/50 (0%)     0/99 (0%)     1/50 (2%)     |
|                                                                                        0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                                                                        0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                                                                        0/50 (0%)     0/50 (0%)                   |
| Overall Incidence                                                               Total 1/659 (0.15%)    Mean 0.18%   SD 0.6%      |
 __________________________________________________________________________________________________________________________________
|#Uterus:                                                                                                                          |
|   Polyp Stromal                                                                        0/50 (0%)     2/99 (2%)     0/50 (0%)     |
|                                                                                        1/50 (2%)     0/50 (0%)     0/50 (0%)     |
|                                                                                        2/50 (4%)     1/100(1%)     2/60 (3%)     |
|                                                                                        3/50 (6%)     0/50 (0%)                   |
| Overall Incidence                                                               Total 11/659 (1.67%)   Mean 1.67%   SD 2.04%     |
 __________________________________________________________________________________________________________________________________
|#Uterus:                                                                                                                          |
|   Sarcoma Stromal or Polyp Stromal                                                     0/50 (0%)     2/99 (2%)     0/50 (0%)     |
|                                                                                        1/50 (2%)     0/50 (0%)     0/50 (0%)     |
|                                                                                        2/50 (4%)     1/100(1%)     2/60 (3%)     |
|                                                                                        3/50 (6%)     0/50 (0%)                   |
| Overall Incidence                                                               Total 11/659 (1.67%)   Mean 1.67%   SD 2.04%     |
 __________________________________________________________________________________________________________________________________
|#Zymbal's Gland:                                                                                                                  |
|   Carcinoma                            0/50 (0%)     0/100(0%)     0/49 (0%)           1/50 (2%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 0/659 (0%)      Mean 0%      SD 0%        Total 1/659 (0.15%)    Mean 0.18%   SD 0.6%      |
 __________________________________________________________________________________________________________________________________
|#Zymbal's Gland:                                                                                                                  |
|   Carcinoma or Adenoma                 0/50 (0%)     0/100(0%)     0/49 (0%)           1/50 (2%)     0/99 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/50 (0%)     0/50 (0%)           0/50 (0%)     0/50 (0%)     0/50 (0%)     |
|                                        0/50 (0%)     0/100(0%)     0/60 (0%)           0/50 (0%)     0/100(0%)     0/60 (0%)     |
|                                        0/50 (0%)     0/50 (0%)                         0/50 (0%)     0/50 (0%)                   |
| Overall Incidence               Total 0/659 (0%)      Mean 0%      SD 0%        Total 1/659 (0.15%)    Mean 0.18%   SD 0.6%      |
 __________________________________________________________________________________________________________________________________
