ABSTRACT
Water and soil pollution caused due to the accumulation of excess amounts of heavy metals is a serious threat across the globe. The heavy metals that are predominantly recognized as pollutants in the environment are arsenic, cadmium, chromium, copper, lead, mercury, nickel and zinc. The effluents released from industrial wastes, electronic wastes and discharge of agricultural activities in the environment are common sources of heavy metals present in water and soil. These heavy metals are then absorbed by plants and aquatic animals, thereby entering the food chain. The hazardous effects of heavy metals on human beings include birth defects, kidney and liver deterioration, skin lesions and cancers. Nanotechnology has been playing an effective role in addressing several environmental challenges faced in the recent era. Applications of various nanoparticles, nanoadsorbents, nanophotocatalysts and nanomembranes are some of the advantageous methods for the remediation of heavy metals contamination from the environment. Efficient approaches such as adsorption, conversion, redox and stabilization are widely implemented for the remediation of heavy metals using nanoparticles. Nanoparticles are prepared using mechanical or biological and microbial mechanisms as fundamental sources, thereby exhibiting unique biological, physical and chemical characteristics. The increased aspect ratio, better pore volume and larger surface area of nanoparticles enhance the catalysis and sorption process. A detailed study regarding the application of nanoparticles in the removal of heavy metals with their advantages and drawbacks is discussed in this chapter.
