Toxicity of ethyl formate to adult Sitophilus oryzae (L.), Tribolium castaneum (herbst) and Rhyzopertha dominica (F.)

Fumigations were conducted using a continuous flow-through laboratory process to maintain constant concentrations of ethyl formate and low levels (<0.8%) of respiratory carbon dioxide. The procedure minimised the effects of sorption by exposing test insects without media and minimised the effect of carbon dioxide by use of continuous flow. The concentration x time (Ct) products of ethyl formate for adult Sitophilus oryzae, Tribolium castaneum and Rhyzopertha dominica at 25 degrees C and 70% relative humidity for the 6 It exposure were, respectively: (1) LD50 107.8, 108.8 and 72.8 mg h L-1 and (2) LD99.5 207.4, 167.1 and 122.2 mg It L-1. Endpoint mortality was reached within 24 h of initial exposure. Crown Copyright (C) 2008 Published by Elsevier Ltd. All rights reserved.