ABSTRACT

Lindane, γ isomer of hexachlorocyclohexane (HCH), has been used to control numerous species of insects in field crops. The use of technical HCH has been banned in western countries, but it still finds extensive use in several developing and tropical countries as the insecticide of choice in the plant protection and vector control programs. In the 1980s, an extensive discussion among agricultural ecologists took place to explain the residue sources of HCH isomers in the soil, plant products, and milk. Despite the fact that many years ago technical HCH was banned worldwide and only a few governments permitted the use of lindane in agriculture, it still was observed in different elements of the environment and food chain residues of α- and ß-HCH. Field conditions have greater variability that cannot be controlled. For this reason, field investigations for the bioisomerization phenomenon of lindane were prompted to evaluate the magnitude and confirm previous laboratory results.