Ninety-day toxicity and one-generation reproduction study in rats exposed to allethrin-based liquid mosquito repellent.

Rats exposed to liquid mosquito repellent (LMR) containing allethrin (3.6% w/w) 8-hrs/ day for a period of ninety days did not produce any signs of toxicity or death. Significant increases in relative weight of liver and adrenal in males, brain and thyroid in females were observed. No significant changes were noticed in clinical enzyme profile, gonadal enzymes and histopathology of vital organs except mild changes in the activities of liver and serum alkaline phosphates (ALP), testicular glucose-6-phosphate dehydrogenase (G-6PDH) and epididymal sorbitol dehydrogenase (SDH). Rats exposed to LMR for one generation had not produced changes in their reproductive indices such as fertility index, gestation index, live pups/ dam and sex ratio. There was no change in the preweanling evaluation of pups such as survival and growth index on post-natal days (PND) 0, 4, 7,14 and 21. No significant pathomorphological changes were observed in liver, brain, kidney and gonads of PND 21 pups. Absences of any major adverse effects in the adult as well as weanling rats suggest the safe use of allethrin-based LMR.