The effects of trichlorfon on maternal reproduction and mouse embryo development during organogenesis.

The organophosphate pesticide trichlorfon is a widely used agricultural broad spectrum insecticide. The health effects on a developing fetus of low level exposure to trichlorofon ingested by the mother in contaminated foods are unclear. We assessed reproductive and developmental toxicity in pregnant female mice following gavage-administered exposure to distilled water or to low levels (12.5, 25, or 50 mg/kg body weight/d) of trichlorofon during organogenesis (gestation days 6-15). Following sacrifice on day 17, reproductive outcomes and teratogenesis were assessed. Trichlorfon exposure did not affect maternal weight gain, organ weights, corpora lutea, implantation sites, or reproductive success, nor where external or skeletal abnormalities evident. The lack of effects of trichlorfon on any in vivo reproductive and fetuses endpoints above suggested that for trichlorfon, a hazard of reproductive toxicity below 50 mg/kg body weight/d maybe not expected. However, a well-designed epidemiological study is necessary for further risk assessment of human developing fetus exposed to trichlorfon at a lower level.