Effect of halogenated benzenes on the toxicity and metabolism of malathion, malaoxon, parathion, and paraoxon in mice

摘要: The halogenated benzenes, inducers of xenobiotic metabolism, were studied for their effects on the metabolism malathion, malaoxon, and paraoxon toxicity lethality these organophosphorus insecticides parathion. One millimole per kilogram 1,4-dichlorobenzene, 1,2,4-trichlorobenzene, 1,4-dibromobenzene, 1,2,4-tribromobenzene, or hexabromobenzene 0.1 mmol/kg hexachlorobenzene was administered po to male mice daily 7 days. In general, trihalogenated benzenes increased LD50 all four two- sixfold. These increases larger than those observed with di- hexahalogenated isomers. bromine-substituted usually more active chlorinated ones exception being hexabromobenzene. There a good correlation between in vitro carboxylesterase activity either malathion malaoxon as substrate. decreased inhibitory effect cholinesterase brain lesser degree red blood cells, but not liver plasma. also protection against parathion lethality, inhibition by paraoxon, dearylation microsomal mixed-function oxidases hepatic plasma esterases. It appears that are able protect insecticide toxicity. With may be important, oxidase play role. Other changes such dealkylation tissue binding cannot excluded from contributing seen.