Health hazards of hexavalent chromium (Cr (VI)) and its microbial reduction

ABSTRACT

Industrial effluents/wastewater are the main sources of hexavalent chromium (Cr (VI)) pollutants in the environment. Cr (VI) pollution has become one of the world’s most serious environmental concerns due to its long persistence in the environment and highly deadly nature in living organisms. To its widespread use in industries Cr (VI) is highly toxic and one of the most common environmental contaminants. Cr (VI) is frequently non-biodegradable in nature, which means it stays in the environment for a long time, pollutes the soil and water, and poses substantial health risks to humans and wildlife. In living things, the hexavalent form of Cr is carcinogenic, genotoxic, and mutagenic. Physico-chemical techniques currently used for Cr (VI) removal are not environmentally friendly and use a large number of chemicals. Microbes have many natural or acquired mechanisms to combat chromium toxicity, such as biosorption, reduction, subsequent efflux, or bioaccumulation. This review focuses on microbial responses to chromium toxicity and the potential for their use in environmental remediation. Moreover, the research problem and prospects for the future are discussed in order to fill these gaps and overcome the problem associated with bacterial bioremediation’s real-time applicability.

Graphical abstract

KEYWORDS:

• Microbial bioremediation
• biosorption
• environmental contaminates
• health hazards
• chromium toxicity

Acknowledgements

This research is supported by the National Research Foundation, Prime Minister’s Office, Singapore under its Campus for Research Excellence and Technological Enterprise (CREATE) program.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the National Research Foundation, Prime Minister’s Office, Singapore under its Campus for Research Excellence and Technological Enterprise (CREATE) programme. [NA].