Percutaneous absorption of carbon 14 labeled insect repellents in hairless dogs.

The percutaneous penetration of three insect repellents was determined in hairless dogs. Each compound was administered intravenously and topically to three dogs. Urine, feces and blood samples were assayed for radioactivity by scintillation counting. The percent penetration for N,N-diethyl-m-toluamide (m-deet, the most widely used insect repellent), its isomer N,N-diethyl-p-toluamide and 2-ethyl-1,3-hexanediol were 7.9%, 7.6%, and 10.3% respectively. The results for m-deet penetration in the hairless dog are comparable to those in man.