Advances in bioremediation of hexavalent chromium: cytotoxicity, genotoxicity, and microbial alleviation strategies for environmental safety

Abstract

Chromium(VI) is discharged into the environment from different sources and industrial activities. Cr(VI) is used in many industries at high concentrations (Pattanapipitpaisal et al., 2001; Sultan and Hasnain, 2007) and various functions of different industries give rise to chromium-containing effluents (Lauwerys et al., 2007). When industries release chromium(VI)-containing effluent into water bodies or into soil, it results in its accumulation in these bodies, mostly through immobilization, and ultimately leads into the food chain. The United States Environmental Protection Agency has categorized this metal as one of the 17 chemicals that are of greatest threat to humans (Marsh and Mclnerney, 2001) and its permissible limit in drinking water is 0.05 mg/L. Hexavalent chromium causes irritation, lung carcinoma, and corrosion of the skin and respiratory tract in human beings (Wang et al., 2014). Cr(VI) also affects transcription, translation, and protein expression of the cell (Karthik et al., 2016). High concentrations of Cr(VI) may result in the inhibition of plant growth, change in nutrient status, chlorosis, and change in plasma and cell membrane stability and permeability, reduction in photosynthesis, and high ROS release...