Bioassay of XXXX for possible carcinogenicity.

@entity242 @entity19 @entity37313 @entity5 @entity5426 @entity2698 @entity1492 @entity421 @entity35
A bioassay of @entity37313 for possible carcinogenicity was conducted by administering the test chemical in feed to F344 @entity35 and B6C3F1 @entity19 . Groups of 50 @entity35 of each sex were administered @entity37313 at one of two doses, either 200 or 400 ppm, for 105 or 106 weeks. Matched controls consisted of 20 untreated @entity35 of each sex. All surviving @entity35 were killed at the end of administration of the test chemical. Groups of 50 male @entity19 were administered @entity37313 at one of two doses, either 200 or 400 ppm, for 105 weeks. Groups of 50 female @entity19 were administered the test chemical at one of two doses, initially 400 or 800 ppm, for 38 weeks. Because of excessively lowered body weights in the dosed groups of the females, doses for the females were then reduced to 100 and 400 ppm, respectively, and administration at the lowered doses was continued for 67 or 68 weeks. The time-weighted average doses for the female @entity19 were either 208 or 545 ppm. Matched controls consisted of 20 untreated @entity19 of each sex. All surviving @entity19 were killed at the end of administration of the test chemical. Mean body weights of dosed @entity35 and @entity19 of each sex were lower than those of corresponding controls, and were generally dose related throughout the bioassay. Mortality was dose related in the male @entity35 and the female @entity19 , but was not significantly affected in either the female @entity35 or the male @entity19 . Survival was 70% or greater at week 90 on study in all dosed and control groups of each species and sex; thus, sufficient numbers of animals were at risk in all groups for the development of late-appearing @entity5 . In @entity35 , a large number of @entity242 , including @entity1492 , @entity5426 , and @entity421 in both males and females and malignant @entity2698 in females, occurred in the spleen and other abdominal organs at incidences that were dose related in each sex (P<0.001) and that in direct comparisons were significantly higher (P<0.001) in the high-dose groups of each sex than in the corresponding control groups (males: controls, 0/20, low-dose 6/49, high-dose 31/49; females: controls 0/20, low-dose 5/50, high-dose 21/50). In @entity19 , no @entity5 occurred in either males or females at incidences that were significantly higher in the dosed groups than in the corresponding control groups. It is concluded that under the conditions of this bioassay, @entity37313 was carcinogenic (sarcomagenic) for F344 @entity35 , inducing various types of @entity242 in the spleen and other abdominal organs of both males and females. The test chemical was not carcinogenic for B6C3F1 @entity19 of either sex.
