DEET (N,N-Diethyl-meta-toluamide) induced delay of blow fly landing and oviposition rates on treated pig carrion (Sus scrofa L.)

We asked if N,N-Diethyl-meta-toluamide (DEET) affects fly landing and oviposition rates on pig surrogates of human decedents, in part to determine if the common habit of wearing DEET as an insect repellant could affect the rate of human decomposition. Dead pigs were sprayed with DEET in a rural ecosystem and fly behavior and maggot development and colonization levels were compared to non-sprayed controls. Pigs treated with DEET experienced a significant delay in fly visitation and oviposition, time to each larval instar, and total larval quantity (p<0.01 for all), with subsequently reduced decomposition. Such changes in fly behavior and larval population development would significantly impact estimation of the period following death from entomological evidence in decedents wearing DEET at the time of death, which could have important consequences for criminal cases incorporating entomological evidence.