Microbial degradation of the pesticide lindane (γ-hexachlorocyclohexane)

Abstract

Publisher Summary This chapter discusses environmental persistence, toxicology, and biochemical and molecular aspects of Hexachlorocyclohexane (HCH) biodegradation. Increased and indiscriminate use of chemical pesticides causes considerable environmental pollution and human health problems due to their toxicity, persistence, and transformation into hazardous metabolites. Halogenated aromatic compounds, particularly chlorinated aromatics, have been utilized in agriculture and industry for many years as insecticides, herbicides, solvents, lubricants, plasticizers, and insulators. HCH or BHC (benzene hexachloride), is one of the most extensively used organochlorine insecticides. Factors that affect the degradation of organochlorine compounds include the number of attached halogens, the stability of the genes encoding the detoxification pathway, the mass transfer properties of the contaminant, and the contaminant degrading organisms and properties of the soil or water. Genetically engineered microorganisms (GEMs) can be used to bring about rapid degradation of pesticide residues by adding large amounts of prepared inoculums. The effects that GEMs may have on the ecosystem could also be affected by their mode of introduction, their spatial and temporal distribution, and the physicochemical and biological characteristics of the environment to which they are released.