Insights into Microbe Mediated Arsenic Release to Groundwater Focusing on Bangladesh and India

Abstract

Arsenic (As) contamination of ground water is a potential threat to human population in several countries throughout the world. Subsurface aquifer sediments act as the principle source point of arsenic pollution in ground water. Microbial activities have been reported to influence As release and speciation in the groundwater from the subsurface sediments. One of the most important group of microorganisms responsible is the dissimilatory arsenate reducing prokaryotes (DARP) which use arsenate as electron acceptor and solubilize arsenic from sediments. Several genes are responsible for metabolism of As (III/V) and thus to release of As from sediments, such as arr (dissimilatory arsenate reductase gene) and ars genes (arsenate reductase). These genes have been found to be distributed across diverse phylogenetic population. Several recent studies have also pointed to the role of organic matter in the release of As from the sediments, which has led to a huge scope for research in relation to metatranscriptomic analysis of arsenate reduction.