"When we compared the chemical signatures of the different water sources in our study area to the signatures of the aquifer water, we saw that water with high arsenic content originates from the human-built ponds, and water with lower arsenic content originates from the rice fields," said Neumann, now a postdoctoral associate at Harvard University. "It's likely that these same processes are occurring at other sites, and it suggests that the problem could be alleviated by digging deeper drinking water wells below the influence of the ponds or by locating shallow drinking wells under rice fields."
Next steps
Harvey and other researchers plan to provide deep wells for several villages at geographically distinct locations, and combine hydrologic and biogeochemical testing of those wells with a study of villagers' health improvements, with specific interest in children's neurological development. A goal of this study is to develop practical guidelines for safe wells.
Source: "Anthropogenic influences on groundwater arsenic concentrations in Bangladesh," by Rebecca B. Neumann, Khandaker N. Ashfaque, Charles F. Harvey et al, in the Nov. 15 online edition of Nature Geoscience.
Funding
This research was funded by the Division of Earth Sciences of the National Science Foundation and the Center for Environmental Sensing and Modeling of the Singapore-MIT Alliance for Research and Technology.
Written by Denise Brehm, MIT News Office
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