Organophosphorus Insecticides

Abstract Many organophosphorus (OP) insecticides including acaricides and nematicides are used in agriculture and public health all over the world; they are the largest insecticide group with some 38% of worldwide sales in 1996. Their variety in structure reflects the broad range of their physicochemical properties such as water solubility, lipophilicity, volatility, and persistency in the environment. Owing to this wide range of physicochemical properties, OP insecticides offer various degrees of activities in soil, in plants, in the vapor phase, and against a variety of pests, though they exhibit a single mode of action, i.e., acetylcholinesterase inhibition. In this entry, the description of general principles on the synthesis, chemical reactions, mode of action and toxicity, metabolism, and environmental fate is followed by that of individual OP insecticides, which involve 71 currently used chemicals. The names of discussed chemicals are as follows: acephate, azamethiphos, azinphos‐ethyl, azinphos‐methyl, cadusafos, chlorethoxyfos, chlorfenvinphos, chlormephos, chlorpyrifos, chlorpyrifos‐methyl, coumaphos, cyanophos, demeton‐ S ‐methyl, diazinon, dichlorvos, dicrotophos, dimethoate, dimethylvinphos, disulfoton, EPN, ethion, ethoprophos, etrimfos, famphur, fenamiphos, fenitrothion, fenthion, flupyrazofos, fonofos, formothion, fosthiazate, heptenophos, isazofos, isofenphos, isoxathion, malathion, mecarbam, methacrifos, methamidophos, methidathion, mevinphos, monocrotophos, naled, omethoate, oxydemeton‐methyl, parathion, parathion‐methyl, phenthoate, phorate, phosalone, phosmet, phosphamidon, phoxim, pirimiphos‐ethyl, pirimiphos‐methyl, profenofos, propaphos, propetamphos, prothiofos, pyraclofos, pyridaphenthion, quinalphos, sulfotep, sulprofos, tebupirimfos, temephos, terbufos, tetrachlorvinphos, thiometon, triazophos, trichlorfon, and vamidothion.