Insights into biogeochemical cycle of mercury, contamination sources and its detoxification techniques. A sustainable approach towards biological remediation.

 Mercury (Hg), the environmental toxicant is present in the soil, water, and air as it is substantially distributed throughout the environment. Being extremely toxic even at low concentration, its remediation is utterly important. Therefore, it is necessary to detoxify the contaminant within the acceptable limits before threatening the environment. Although various conventional methods are used, irrespective of being costly, producing intermediate by-product. Biological methods are eco-friendly, clean, greener and safer for the remediation of heavy metals corresponding to the conventional remediation due to their economic and high tech constraints. Bioremediation is now being used for the Hg (II) removal, which involve  biosorption and biaccumulation mechanism or both, also mercuric ion reductase, expolysasscaharide  play significant role in detoxification of mercury by acting a potential instrument for the remediation of heavy metals. In this review paper, we shed light on problems caused by mercury pollution, mercury cycle and its global scenario and detoxification approaches by biological class and the result found in the literature.