Journal
GEOBIOLOGY
Volume 8, Issue 2, Pages 155-168Publisher
WILEY
DOI: 10.1111/j.1472-4669.2010.00233.x
Keywords
-
Funding
- NERC [NE/D013291/1]
- PRAMA
- British Council
- UK Department for Innovation, Universities and Skills (DIUS), Office of Science and Innovation
- FCO, Department of Science and Technology, Government of India
- India Higher Education Sector
- UK Higher Education Sector
- Bristol node of the Life Sciences Mass Spectrometry Facility [F14/6/13/01]
- NERC [NE/D013291/1, NE/D014069/1] Funding Source: UKRI
- Natural Environment Research Council [NE/D014069/1, NE/D013291/1] Funding Source: researchfish
Ask authors/readers for more resources
High arsenic concentrations in groundwater are causing a humanitarian disaster in Southeast Asia. It is generally accepted that microbial activities play a critical role in the mobilization of arsenic from the sediments, with metal-reducing bacteria stimulated by organic carbon implicated. However, the detailed mechanisms underpinning these processes remain poorly understood. Of particular importance is the nature of the organic carbon driving the reduction of sorbed As(V) to the more mobile As(III), and the interplay between iron and sulphide minerals that can potentially immobilize both oxidation states of arsenic. Using a multidisciplinary approach, we identified the critical factors leading to arsenic release from West Bengal sediments. The results show that a cascade of redox processes was supported in the absence of high loadings of labile organic matter. Arsenic release was associated with As(V) and Fe(III) reduction, while the removal of arsenic was concomitant with sulphate reduction. The microbial populations potentially catalysing arsenic and sulphate reduction were identified by targeting the genes arrA and dsrB, and the total bacterial and archaeal communities by 16S rRNA gene analysis. Results suggest that very low concentrations of organic matter are able to support microbial arsenic mobilization via metal reduction, and subsequent arsenic mitigation through sulphate reduction. It may therefore be possible to enhance sulphate reduction through subtle manipulations to the carbon loading in such aquifers, to minimize the concentrations of arsenic in groundwaters.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available