Organophosphorus poisoning: A comparative study of the toxicity of chlorfenvinphos [2-chloro-1- (2′, 4′, -dichlorophenyl) vinyl diethyl phosphate] to the pigeon,the pheasant and the Japanese Quail

The acute oral toxicity of chlorfenvinphos 2-chloro-1-(2′, 4′-dichlorophenyl)vinyl diethyl phosphate] was measured in pigeon (Columba livia), pheasant (Phasianus colchicus), and quail (Coturnix coturnix japonica) and the compound was shown to be particularly toxic to pigeons. Additionally, all three species were fed chlorfenvinphos at 100 ppm in their diet for two or four weeks and esterase measurements were made by conventional and electrophoretic methods on extracts of liver, kidney and brain. The conventionally measured esterase inhibition correlated well with the acute oral toxicity figures. A more detailed study of the histochemically stained electrophoregams showed some discrepancies compared with conventional methods but offered a possible explanation of the inter-species toxicity difference in that it revealed differential inhibition of some brain iso-esterases in pigeon but not in pheasant or quail.