Arsenic pollution in the environment: Role of microbes in its bioremediation

Arsenic (As) pollution in drinking water and soils poses a threat to over 100 million people worldwide, making it one of the largest environmental catastrophes particularly in Bangladesh and West Bengalwhere more than one-third of the population are at risk. Microbial As metabolism and mobilization in aqua system is relatively a recent issue.The presence of the arsenic oxidation, reduction, and extrusion genes (aioA, arrA, arsB, and acr3) are explored within microorganisms retrieved from As-contaminated environments. However, the nature of microbiome involved within a certain As transformation environment is still an area of research, specifically how microbial redox transformations occur, that can be exploited to mitigate the longstanding problem. The present chapter overviews the mechanism of As pollution in various environment, microbial diversity in such environment, correlation of their activities to the biogeochemistry of As and finally application of microbes as a bioremediation tool for As detoxification and bioremediation.