Arsenic in Bangladesh's Drinking Water: Evaluating Factors That Have Hindered Two Decades of Mitigation Efforts, and the Opportunities to Address Them

Abstract

The discovery in the late 1990s that as many as 70 million people in Bangladesh were exposed to naturally occurring arsenic through their drinking water sources sparked widespread efforts to mitigate the risks. The intensity of these efforts declined after the mid-2000s and the limited monitoring done since has raised concerns about their long-term sustainability. The most recent Multiple Indicator Cluster Survey conducted by the Government of Bangladesh and UNICEF indicated that in 2012-2013 over 40 million people still drank water that tested above the World Health Organization (WHO) guideline for arsenic in drinking water, showing that it remains a major public health concern. This dissertation aims to elucidate barriers to reducing arsenic exposure in Bangladesh, pilot strategies to address them, and generate specific recommendations for the broad range of water supply stakeholders. The research was performed by researchers at the University of Michigan and Asia Arsenic Network, a water focused NGO in Bangladesh. The researchers worked closely with a diverse range of stakeholders to define problems and design study approaches. Field data collection was done in Phulsara and Goga unions in the southwest of Bangladesh. We investigated the state of arsenic mitigation efforts in the two study unions through an assessment of existing water supply infrastructure and surveys of rural households to understand their perceptions and behaviors regarding drinking water. The results indicate a need for better water supply planning, with mitigation strategies currently in place failing due to crumbling community water infrastructure and low levels of adoption of safe water practices. The effect of a low-cost (< USD 9/household) informational intervention on reducing arsenic exposure in arsenic affected rural households was evaluated through a randomized control trial study. The intervention consisted of sharing arsenic awareness messaging, an individual household water quality test result, and specific recommendations for alternate sources with improved water quality. The results show that the intervention led to a significant number of households changing water sources, thereby lowering arsenic exposure. This work highlights the benefit of continued well xv

testing and educational programming in Bangladesh, efforts that have declined sharply since 2006. While the majority of community operated water systems fail within three years of installation, our work with the user communities of two such systems, has identified initiatives that can improve their sustainability. We documented these cases in a short video, which is intended to inform and motivate other rural communities to better manage their water infrastructure. The research further included a critical assessment of eight commercially available arsenic field test kits. While arsenic test kits are widely used in Bangladesh, an up-to-date assessment of their accuracy was lacking in the scientific literature. The results of this study show that several test kits, including the one currently most commonly used in Bangladesh, can provide variable results and often significantly underestimate arsenic levels. Finally, specific recommendations based on the work performed in this dissertation are provided for a range of water supply stakeholders in Bangladesh including government agencies, donor organizations, non-governmental organizations, and field kit manufacturers. The findings from this work are intended to draw attention to the continuing need for additional arsenic mitigation efforts and help the wide range of water supply stakeholders in Bangladesh make more informed decisions in their work.