DOI: 10.1126/science.1076978 ISSN:
Arsenic Mobility and Groundwater Extraction in Bangladesh
Charles F. Harvey, Christopher H. Swartz, A. B. M. Badruzzaman, Nicole Keon-Blute, Winston Yu, M. Ashraf Ali, Jenny Jay, Roger Beckie, Volker Niedan, Daniel Brabander, Peter M. Oates, Khandaker N. Ashfaque, Shafiqul Islam, Harold F. Hemond, M. Feroze Ahmed- Multidisciplinary
High levels of arsenic in well water are causing widespread poisoning in Bangladesh. In a typical aquifer in southern Bangladesh, chemical data imply that arsenic mobilization is associated with recent inflow of carbon. High concentrations of radiocarbon-young methane indicate that young carbon has driven recent biogeochemical processes, and irrigation pumping is sufficient to have drawn water to the depth where dissolved arsenic is at a maximum. The results of field injection of molasses, nitrate, and low-arsenic water show that organic carbon or its degradation products may quickly mobilize arsenic, oxidants may lower arsenic concentrations, and sorption of arsenic is limited by saturation of aquifer materials.