Organophosphorus and Carbamate Insecticides

Publisher Summary Organophosphorus and carbamate insecticides inhibit the cholinesterase (ChE) of animals and insects. This accounts for their toxicity to warm-blooded animals and to a large extent for their effectiveness in the control of insects. Many of these insecticides, and also some of their oxidation and metabolic products, are such powerful inhibitors of cholinesterase that sensitive enzymatic methods for their micro-determination are developed on the basis of this inhibitory property. This chapter discusses the most widely used method in which the inhibition of an enzyme is used for the analysis of insecticides. The method is based on Michel's simplified method for the estimation of cholinesterase activity in human red blood cells and plasma. The cholinesterase used in this method must be carefully standardized to avoid any interference from other related esterases. The method is useful in agriculture and food chemistry. The chapter also discusses the principle and the procedure of the method. The sensitivity of the method depends on the inhibitory action of the insecticide to be determined.