Dermal Penetration and Distribution of 14C-Labeled Permethrin Isomers

The insecticide permethrin was assessed for skin absorption potential in rabbits and dogs following a single application. Radiolabeled cis and trans isomers of permethrin were used. Radiocarbon appearing in excreta for one or two weeks following treatment was the measure of absorption. Rabbits absorbed about 30 percent of the topical dose, generally appearing in urine within 24 hours. Dogs demonstrated similar kinetics though only 10 percent absorption occurred. Enteric elimination was significant in dogs. Absorption of permethrin in man should be less than 8 percent of the applied dose.