摘要:The present review describes the structure of anticholinesterase organophosphates (OPs), which are worldwidely and predominantly used as insecticides, in relation to the poisonous gas (possibly sarin-poisoned) disaster happened recently in Matsumoto-city, Nagano. As evident from the disaster, many OP compounds have caused the severe toxicity and even death in humans and domestic animals. The toxicity, chemical structures, mechanism of action (cholinesterase inhibition), clinical signs and syndromes, antidotes and treatment, and prophylactics of nerve gases and OPs are described and discussed. The general metabolic fates of OP insecticides are also dealt with in this review. Some OPs including insecticides have been known to cause chronic toxicity, particularly delayed-type neuropathy (organophosphorus ester-induced delayed neuropathy, OPIDN), which is currently understood to be due to the inhibition of nerve toxic esterase or neuropathy target esterase. OPIDN still has the merit of further study and thus I describe here in detail, because it contributes to the long-term morbidity in cases of severe acute, or chronic, exposure to OPs.