Dangerously high levels of arsenic have entered into the drinking water supply of millions of people in Bangladesh and Eastern India. The arsenic appears to be coming up from wells installed for the purpose of avoiding disease in pond and surface water, which claimed millions of lives in the past. Long-term arsenic poisoning threatens increased incidence of bladder, skin, lung and other cancers and painful and disabling skin lesions on the soles of hands and feet. The World Bank has led efforts to test and mark contaminated wells. Scientists from around the world are engaged in efforts to study how the arsenic, a common element in the earth's crust, is attaining hazardous concentrations in ground water, as well as investigate how to avoid, prevent or counter this, how to remove arsenic from pumped water, and how to treat those affected by arsenic poisoning. American scientists are among those leading this research, and in several projects, they are supported by experts and ftuids from the United States Government.
UNITED STATES GEOLOGICAL SURVEY
The USGS and the Geological Survey of Bangladesh (along with the Geological Survey of India and potential partners in Nepal) are conducting a collaborative investigation of the conditions and processes controlling the high arsenic concentration in ground water. The USGS activities are planned for four years with support from the US State Department’s Economic Support Fund. So far $200,000 has been provided by State for this work, and a further $250,000 has been allocated. The scientists are working to analyze samples of soil, sediment and water to describe the solid-phase residence of arsenic and the chemical transformations that release the arsenic to the water. Solid-phase samples are being collected from excavations and boreholes. Water samples are being gathered by installing wells at multiple depths in the immediate vicinity of the boreholes so that the correspondence of the solid and water composition can be evaluated. The initial efforts have been focused in eastern and central Bangladesh. In 200 1, work included investigation of zones of arsenic enrichment beneath cultivated lands, collection of samples from additional river basins to contrast sediment compositions and verify changes in the form of arsenic in the sediment with increasing depth.
The goal of the USGS work is to develop an understanding of the sources and sinks of arsenic in the sediment and integrate this result with sedimentology and hydrology. Future work will be at other locations on the Bengal delta and Gangetic Plain (including India and possibly Nepal with the intent of adding to efforts of other research teams and co-operatively developing a unified explanation of controls on dissolved arsenic.
EPA SUPERFUND/NIH
Led by Columbia University, this five-year $11m program, entitled "Health
Effects and Geochemistry of Arsenic and Lead", includes seven research
projects. Three of the projects take place within the U.S. where arsenic
is present as the result of human activity, while four (roughly $5.5m)
focus on the Bangladesh situation. These include:
1) A Cohort Study of Arsenicosis in Bangladesh; 2) Environmental Arsenic,
Pregnancy, and Children's Health; 3) Arsenic Mobilization in Bangladesh
Groundwater; and 4) Assessment and Remediation of Arsenic Enrichments in
Groundwater. These projects include two partners in Bangladesh, i.e., the
National Institute of Preventive and Social Medicine (NIPSOM) and the Geology
Department of Dhaka University. The projects, funded by the EPA superfund,
are peer-reviewed and fiscally by the National Institute of Environmental
Health Science, of the National Institutes of Health. The projects began
in June 2000 and are scheduled for completion at the end of March 2005.
The Columbia program brings together health, earth and social scientists in jointly seeking to understand and address the multiple facets of the arsenic problem. The first project is a study of 10,000 adults living in Araihazar, a region 20 km east of Dhaka. It is determining the health effects of arsenic exposure on the population, and seeks to develop strategies for medical and nutritional interventions. The second research project concerns itself with the effects of arsenic on pregnancy outcome in women, and will also determine the extent to which prenatal arsenic exposure takes place. This is important because many women of childbearing age have been exposed to arsenic for part, or even all of their lives. In its subsequent years, the project will examine the effects of past arsenic exposure on 6 year-old and 10 year-old children. These two biomedical projects, now well under way, began last year earth when scientists from Columbia's Lamont-Doherty Earth Observatory tested arsenic levels in 5000 contiguous wells serving a community of 60,000 people in Araihazar. The group has learned that 52% of the population in Araihazar currently consumes water that is unsafe by Bangladesh standards. Medical field clinics are being built to handle the communities’ medical problems either on site or through referrals to hospitals.
Building on the survey of 5000 wells described above, the third project concerning arsenic mobilization in groundwater is using geochemical and geophysical techniques to attempt to understand how and why arsenic moves from soil into water. Here again, significant progress has already been made, e.g., in understanding the spatial variability in arsenic concentrations, and in generating knowledge concerning the complex relationships between water arsenic concentrations, oxidation-reduction processes, well depth and sub-surface structure. Earth scientists and engineers are developing strategies to test a number of approaches to alternative drinking water, including well-switching (i.e., using another person's safe well), targeted drilling of deeper wells, and various arsenic removal technologies. Social scientists are now disseminating the findings of the well survey, along with a standardized educational program at the local level, in an attempt to bring about a reduction of arsenic exposure in the community. The fourth project is emphasizing the generation of skills at the local level to address the crisis. For example, they are developing inexpensive instrumentation that could be used by the local well installers to assure that wells are safe. The Columbia team has submitted a training grant application to the Fogarty Center of the U.S. National Institutes of Health to obtain funds to provide multi-disciplinary training to Bangladeshi pre- and post-doctoral fellows interested in tackling the arsenic problem at Columbia University in public health, earth science and social sciences. The team is also actively seeking funding to conduct a thorough evaluation of the most promising remediation options.
SANDIA LABS
Researchers at Sandia National Laboratories are engaged in a two-pronged effort that has potential implications for the arsenic problem in Bangladesh. In collaboration with the International Atomic Energy Agency (IAEA), Sandia is performing mineral surface analyses of arsenic-contaminated shallow aquifer material in the hopes of unraveling the geochemical controls on arsenic mobilization that is affecting the water that the largest fraction of people now drink. These results are being combined with historical IAEA water analyses from the deeper aquifer to develop a general model of arsenic origins and mobilization in Bangladesh that might be used to anticipate future water quality trends. In parallel, Sandia is developing and testing new techniques for cheaply removing arsenic water from contaminated waters. Sandia's $900,000 project began October 2000 and is scheduled to complete in September 2003.
TRADE AND DEVELOPMENT AGENCY
TDA has provided a $267,500 Grant to the Government of Bangladesh (acting through the Ministry of Local Government and Rural Development) to have Tetrahedron, Inc. of Baltimore, MD develop a treatment system that is both technically and socially acceptable to the people of Bangladesh. The objective of the study is to identify parameters that will need to be modified or adjusted to adapt Tetrahedron's equipment for the treatment of arsenic contaminated water, and to demonstrate a treatment system that is suitable to the conditions in Bangladesh.
In order to make the system universally acceptable, taking into consideration the variability in conditions (such as contamination level, flow rate and competing chemicals) at various locations of Bangladesh, the treatment system is being adapted to meet the treatment requirements of these sites. Additionally, an adapter will have to be designed that will connect the well-head to the treatment system facilitating quick disconnection for regeneration and replacement of treatment equipment.
250 wells throughout Bangladesh are being tested. As of March.2001, the testing phase is nearly complete. Once the project, including review of the waste removal, has been studied, the project will be ready for implementation with World Bank funding.
NATIONAL SCIENCE FOUNDATION
The National Science Foundation has made three grants to research the arsenic problem in Bangladesh. Two companion awards were made to MIT ($302,000) and the University of Cincinnati ($127,000) in August 2000 to do joint, collaborative research on the causes of high arsenic levels in Bangladesh's groundwater and study how and to what degree well sitting, and deep well drilling can avoid arsenic contamination. As of March 2001, the investigators were just beginning to conduct their research, which is expected to be completed in the summer of 2003. An earlier award of $44,000 was made in July 1999 to Columbia University to characterize the subsidence and stratigraphy of the Ganges-Brahmaputra delta and the geologic processes that have shaped them, including the mobilization of naturally occurring arsenic from the underlying sediments. This project is scheduled to be completed in mid-summer 2002. Another NSF award has been recommended for Colorado State University to study arsenic removal from drinking water in Bangladesh. The project abstract is still in draft and the level of funding remains under consideration.