Reproductive and Developmental Toxicity of Triclosan (TCN) in Wistar Rats

Triclosan (TCN) was evaluated for reproductive and developmental toxicity on male and female reproductive performance such as gonadal function, mating behaviour, conception, development of the conceptus and parturition. Wistar rats (10/sex/dose) were administered by oral gavage at the dose levels of 0, 25, 75 and 150 mg/kg bwt/day, prior to mating, during mating and post-mating periods (for males), during pregnancy and up to lactation day 13 (for females). The results showed that, no treatment related mortality or clinical signs. Body weight, food consumption, pre-coital time, gestation length, mating and fertility parameters, percentage of pre- and post-implantation losses, anogenital distance, anogenital ratio were not affected by the treatment. The male pups did not exhibit areola/nipple retention on postnatal day 13. Treatment resulted in significantly lower mean litter size, mean viable litter size and mean number of implantations at 150mg/kg bwt/day. The Thyroid Stimulating Hormone (TSH) and Thyroxine (T4) levels in adult rats and pups were not affected. External evaluation of pups as well as gross and microscopic examination of the reproductive organs of the parent animals revealed no adverse triclosan related changes. Considering the changes observed in the mean litter size, mean viable litter size, mean number of implantations and Day 4 surviva index at 150mg/ kg bwt/day, the No Observed Adverse Effect Level (NOAEL)” for reproductive toxicity is considered to be 75mg/kg Bwt/day.