Abstract

S. F. Ambali , S. O. Abbas , M. Shittu , T. Dzenda , M. U. Kawu , S. O. Salami and J. O. Ayo

Exposure to some organophosphate (OP) compounds during pregnancy has been associated with adverse health consequence on both the mother and the offspring. The aim of the study was to evaluate the effect of exposure to chlorpyrifos (CPF) during gestation on implantation and on some neonatal parameters in mice. Twenty one virgin Swiss albino mice divided into 3 groups of 7 mice each served as subjects for this study. Mice in group 1 were dosed with corn oil (control), while those in groups 2 and 3 were exposed to CPF at a dose of 15.9 mg/kg (~15% LD 50) and 21.2 mg/kg (~20% LD50), respectively. All the dams were dosed between gestation days (GD) 6 - 15 and monitored for signs of toxicity and gestation length. At birth, the litter size and weight, and the anogenital distance of the pups were measured. The pups were evaluated for physical characteristics and death. The dams were sacrificed at postnatal day 22, and the uterine horns evaluated for number of implantation sites. The results showed a significant decrease in the litter size and weight, and anogenital distance in pups exposed to CPF in utero compared to the control. In addition, all the pups prenatally exposed to CPF were born weak and died few days postpartum. A dose-dependent increase in percentage post-implantation loss was observed in mice dosed with CPF. In conclusion, exposure of pregnant mice to CPF caused increased gestation length, and postimplantation loss, decreased litter size and weight, survivability and anogenital distance.