Source of Cr(VI) in the aquatic ecosystem, its genotoxic effects and microbial removal from contaminated water

Cr(VI) compounds have important industrial applications and are used in various sectors like tanning, chrome plating, anti-corrosion agents and wood preservation. The Cr(VI) contamination in the wastewater is generally due to several natural and anthropogenic sources. Anthropogenic activities like several industrial operations play a major role in the Cr(VI) contamination in the aquatic ecosystem. Cr(VI) well-known toxic metal ion and its exposure in humans causes several health issues. Cr(VI) enters the cells and gradually reduces into a lower oxidation state and generates oxidative stress in the cell which damages cell organelles. The Cr(VI) mediated genotoxicity has been described as damaging the DNA base pairing, sugar-phosphate backbone, histone modification and chromosomal damage. Water and wastewater must be treated to remove Cr(VI) due to its high toxicity. There are several, physiochemical methods used for Cr(VI) remediation but these approaches are expensive and produce hazardous sludge during the treatment process. Therefore, a suitable environmentally friendly and effective Cr(VI) removal approach is urgently needed. Microbial removal of Cr(VI) is considered an eco-friendly and cost-effective process. In this, the authors focused on sources, genotoxicity and microbial remediation approaches of Cr(VI).