Arsenic in Bangladesh
Arsenic is the most toxic and prevalent of the geogenic contaminants, and nowhere is the problem more serious than in Bangladesh. The arsenic was laid down naturally along with the aquifers themselves thousands of years ago, and became mobile as bacteria consumed organic carbon, dissolving iron solids in the process. Since the discovery of arsenic in groundwater in the 1990s, thousands of new arsenic-free water sources have been installed, but tens of millions of Bangladeshis remain exposed to unsafe levels of arsenic in their drinking water. Water Resource Quality is pursuing three related research streams in Bangladesh.
Improved technologies for arsenic mitigation
In some cases, people can reduce their exposure to arsenic by switching to an alternative source, which is free from arsenic. The most common and preferred alternative source is low-arsenic groundwater. Since arsenic levels in the contaminated shallow aquifer vary greatly, sharing of safe shallow tubewells can be one option. Another option is deep tubewells tapping an older aquifer which is much less susceptible to arsenic contamination. However, in some areas deep groundwater contains high levels of iron, manganese, or salinity, which can make the water unacceptable to users. Our work in Sreenagar upazila focuses on optimizing the depth of deep tubewells to reach water which is not only arsenic-free but low in salinity and manganese. Where such a safe depth is found, we are investigating the use of attaching multiple handpumps to a single deep borehole, to allow more people to access safe water.
In some cases there are no adequate arsenic-free alternative sources, at least in the short term. In such cases arsenic removal filters can play an important role. We are partnering with Manob Sakti Unnayan Kendro (MSUK), a local NGO which has developed an award-winning arsenic removal system, the SONO filter. Our research will help to better understand the physical and chemical processes which make this filter effective.
Analysis of the socio-economic and institutional conditions enabling the implementation and maintenance of risk mitigation measures
The main objective of this component is to identify socio-economic and institutions factors which foster or inhibit the development, dissemination, acceptance and propagation of various arsenic mitigation options and their operation and maintenance.
This research focuses on:
1. Identification of the preferences for certain types of arsenic mitigation options by the household level stakeholders living in different regions of Bangladesh.
2. Identification of the various socio-economic factors which influence a household’s preferences to have or not to have arsenic free drinking water.
3. Quantification of the Willingness to Pay (WTP), the Willingness to Accept (WTA) and the Willingness to Walk (WTW) for arsenic free water by analyzing responses from stakeholder groups at different level.
4. Identification of the relationship between a household’s ability and willingness to pay for arsenic free water.
5. Investigation of institutional and socio-economic factors that are hindering or preventing the implementation of sustainable arsenic mitigation options for arsenic free water in the rural villages of Bangladesh.
Analysis of the social acceptance and use of arsenic mitigation options and evaluation of promotion strategies in rural Bangladesh
If and why arsenic mitigation options are being accepted, continuously used and maintained by the population at risk is the focal question of this research project. In a first step, based on a social psychological behavior model, we are investigating, which factors determine the use of different arsenic-safe drinking water options. Based on the results of this pilot survey, we will derive different behavior change strategies to promote the use of arsenic mitigation options. The effectiveness of the implemented strategies will be investigated in a field experiment. Our local partners are the DPHE, UNICEF, NGO Forum and their local partner NGOs: Shetu Bangladesh, Rishilpi Development Project, Society for Disadvantaged Origins (SDO), Tribedi Women Social Development Association (TWSDA), and Voluntary Association for Welfare and Social Development (VAFWSD).
More details about the social acceptance project can be found here: http://sozmod.eawag.ch/project.php?id=15