Organophosphate pesticides: biochemistry and clinical toxicology

Organophosphate pesticides are used extensively worldwide, and poisoning by these agents, particularly in developing nations, is a serious public health problem. The toxicokinetics and toxicodynamics of organophosphate poisoning vary not only with the route and extent of exposure, but also the chemical structure of the agent. The mechanism of toxicity is the inhibition of acetylcholinesterase, resulting in an accumulation of the neurotransmitter acetylcholine and the continued stimulation of acetylcholine receptors. The standard treatment consists of reactivation of the inhibited acetylcholinesterase with an oxime antidote and reversal of the biochemical effects of acetylcholine with atropine. Patients who receive treatment promptly usually recover from acute toxicity but may suffer from neurologic sequelae.