Microbial Cycling of Arsenic in the Aquifers of Bengal Delta Plains (BDP)

Abstract

The element arsenic is abundant on earth's crust. Solubilization due to physicochemical or biologically mediated processes can lead to elevated levels of arsenic in the aquatic environments. In the Bengal Delta Plains (BDP), arsenic mobilization, in particular in aquifers and agricultural lands, has resulted in serious health manifestations among human populations residing in India and Bangladesh. Moreover, the organic matter composition has been shown to be the key component controlling arsenic fluxes in groundwater of BDP region. Microbes have the capability to alter As fluxes and thus can form the basis of cost-effective bioremediation technologies for As-free drinking water. In this chapter emphasis has been laid on the distribution of As and its fluxes across different ecosystems. The fluxes that are controlled by microbial metabolic pathways, which in turn depend on bioavailability and properties of organic matter in the environment, have been highlighted in this chapter.