Toxic effects of butyltin trichloride during early pregnancy in rats

Abstract

The objective of this study was to determine the toxic effects of butyltin trichloride (BTCl) during early pregnancy. Following successful mating, female rats were given BTCl by gastric intubation at 0, 56, 226, or 903 mg/kg on days 0–3 or 4–7 of pregnancy. Female rats were sacrificed on day 20 of pregnancy and fetuses were examined for number, abnormality, mortality, and weight. The maternal body weight gain and food consumption during the administration period was significantly decreased after administration of BTCl at 903 mg/kg on days 0–3 or 4–7 of pregnancy. The pregnancy rate in the BTCl-treated groups was comparable to the control value, regardless of the days on which BTCl was given. The incidence of pre-implantation embryonic loss was not significantly affected after administration of BTCl on days 0–3 or 4–7. In females having implantations, the numbers of corpora lutea, implantations, and live fetuses and the incidences of pre- and postimplantation loss in the groups given BTCl on days 0–3 were comparable to the controls. Although a significant increase in the incidence of postimplantation loss was observed after administration of BTCl on days 4–7 at 56 mg/kg, this change was small and inconsistent across doses and seems unlikely to be toxicologically significant. A significant decrease in weight of female fetuses was found after administration of BTCl at 903 mg/kg on days 0–3 or 4–7. It could be concluded that BTCl treatment during early pregnancy is maternal and developmental toxic at 903 mg/kg.