A review on water pollution by γHCH (lindane) and its removal using nanomaterials

Abstract

Water pollution by the direct discharge of pollutants (fertilizers, pesticides, heavy metals, etc.) into the river without any pretreatment has become a severe environmental/health hazard. Organochlorine pesticides have extensively been used from the 1940s to 1980 as insecticides in agriculture, weedicides, herbicides, etc. Lindane, an organochlorine pesticide, contributes to bioaccumulation in aquatic organisms and biomagnification in the food chain due to its hydrophobic chemical nature and environmentally persistent property with a very slow rate of degradation. Nanotechnology has proven to be very efficient in removing pollutants. Nanomaterials with unique physical and chemical properties have become a tool for toxicant eradication. Some of the properties of nanomaterials, like high reactivity, adhesion, reflectance, surface plasmon resonance to detect toxic materials, quantum effect in which there is no resistance faced by charged particles, small size, and large surface area to volume, enable them to adsorb many toxicants on their surface, thereby assisting in detoxification and removal of pollutants from water. Some examples include the application of nano-zerovalent iron in the oxidation of groundwater, the reusability of photocatalytic membranes, and many more. This review article presents an updated account of some techniques for eradicating lindane from the aqueous medium.