Biotransformation and toxicokinetics of the insect repellent IR3535® in male and female human subjects after dermal exposure

► The absorption and excretion of the insect repellent IR3535® was studied in human subjects after dermal application. ► IR3535® was rapidly metabolized to the corresponding acid. ► Based on the recovery of IR3535® free acid, the skin penetration rate of IR3535® is 13.3% in humans after dermal application.