Effect of carbon disulfide on the anticholinesterase action of several organophosphorus insecticides in mice

Effect of carbon disulfide (CS2) on toxic action of 11 organophosphorus (OP) insecticides were examined by determining the plasma cholinesterase activity in mice. CS2 pretreatment potentiated the anticholinesterase action of parathion and EPN, but suppressed that of dimethoate and diazinon. CS2 had no significant effect or a slightly suppressive effect on the other compounds. Some of these effects were contrasted with the reported alteration of the toxicity following phenobarbital pretreatment. CS2 administration suppressed both detoxification and activation of parathion and EPN by liver microsomes in vitro, as measured by p-nitrophenol production and cholinesterase inhibition, respectively. Causal relationship between the in vitro and in vivo observations, however, remains to be clarified.