The fumigant toxicity of eight essential oil components, 1-8-cineole, carvacrol, eugenol, ()-menthone, ()-linalool, S-()-limonene, ()-
-pinene, and (+)- -pinene, was tested against the cowpea weevil, Callosobruchus maculatus(Fabricius) (Coleoptera: Chrysomelidae), at 0.2560 L/L air doses. 1-8-Cineole, carvacrol, and eugenol caused complete adult mortality at 10 L/L air 24h after treatment. 1-8-Cineole and carvacrol were the most toxic with LD50 values of 0.24 and 0.6 L/L air at 24h, respectively. ()- -Pinene and (+)- -pinene were the least toxic with LD50 values of 31 and 31.4 L/L air at 24h, respectively. Toxicity was negatively correlated with vapor pressure. 1-8-Cineole and carvacrol caused 100% oviposition deterrence at all doses tested. Eugenol and ()-menthone completely inhibited adult emergence. S-()-Limonene, ()- -pinene, and (+)- -pinene were not effective at preventing oviposition or adult emergence, suggesting that a lethal dose of the three oil components would be necessary to control C. maculatusinfestations.