Teratogenicity study on 4-bromophenyl chloromethyl sulfone (BCS) in the rat.

To investigate the teratogenicity of 4-bromophenyl chloromethyl sulfone (BCS), doses of 0, 5, 35 and 245 mg/kg/day of the test substance were administered by oral gavage to Wistar-Imamichi rats from days 6 to 15 of gestation. The results were as follows: The treated dams did not exhibit any toxic symptoms or mortality attributable to the test substance. The following changes were noted in the treated dams: dose-dependent reduction of body weight gain and food intake in 35 and 245 mg/kg groups, and decreased water intake, reduced brain and thymus weights and increased relative weights of liver and kidney in the 245 mg/kg group. Fetal toxicity, increase of mortality and body weight depression, caused by the test substance was not observed. External, skeletal and visceral examination of the fetuses did not reveal any abnormalities ascribed to the test substance. With regard to ossification, the incidence of fetuses with delayed ossification of the 2nd and 5th sternebrae was significantly higher than in the control group. In summary, dams given BCS in doses of 35 mg/kg and 245 mg/kg displayed toxic manifestations. Fetuses showed slightly delayed ossification. However, the test substance was concluded to be free of any lethal or teratogenic effects.