Chapter 40 - Organochlorines

Abstract

Chlorinated compounds, cyclodienes such as aldrin and dieldrin, are used as insecticides. Many methods are used and developed to control or eliminate insects and other plant and animal pests that have threatened man and his food supply. These compounds are found to be noncompetitive antagonists acting on the chloride ion channel of the gamma-aminobutyric acid A (GABA) receptor. GABA is a neurotransmitter in the mammalian and insect central nervous system and the inhibitory neurotransmitter for insects at the neuromuscular junction. GABAA receptors, present in mammalian and insect synapse, are ligand gated chloride ion channels. In mammals, GABAB receptors are coupled to calcium and potassium channels, and the action of GABA is mediated by G-proteins. Cats are the most sensitive species to organochlorine insecticides. Animals recovering from organochlorine insecticide exposure may have to be monitored for a long term because organochlorines can persist in the body for months or years. The source of the exposure must be identified and removed to stop exposure. One decontamination strategy is to reduce feed intake, so that the animal loses body fat, thereby reducing organochlorine residues in adipose tissue. Lactating animals rapidly eliminates organochlorine residues because the residues are excreted in milk.