Radioautographic study of the diffusion of topically applied DDT-C14 into the house fly and its distribution in internal organs.

Abstract

Freeze-drying and radioautographic techniques have been used to study the diffusion of topically applied DDT-C13, into Musca domestica L. and its distribution in the internal organs. Soon after topical application, the insecticide spread over the entire insect body, possibly through the wax mono layer. It did not diffuse through the cuticle, but penetrated into the body through memo areas. The cuticle absorbed the insecticide slowly, apparently from the wax mono layer. Inside the body the maximum concentration of radio activity took place in the alimentary canal, which acquired radio-activity within 15 minutes after topical application. In the midget, radioactivity was concentrated between the gut wall and the peritrophic membrane only. External washings of the fly contained 95% DDT and 5% DDE (1,1-dichloro-2,2-bis( p -chlorophenyl) ethylene.) Fly extracts contained only DDE.