Abstract Several naturally occurring cyanohydrins were tested for fumigation toxicity to two insect species, the house fly (Musca domestica L) and the lesser grain borer (Rhyzopertha dominica (F)). Synthetic analogues of these compounds were tested as well. Most of the cyanohydrins tested were more toxic as fumigants to M domestica and R dominica than chloropicrin; some compounds were nearly as toxic as dichlorvos. Naturally occurring ...