40 million Bangladeshis are drinking arsenic-tainted water
by Marjorie Howard

For four months of the year, Bangladesh has an overabundance of water as monsoons flood 70 percent of the land; during the winter months, the country contends with drought-like conditions. For centuries, people relied on surface water for drinking and irrigation, but poor sewage systems and industrial waste meant the water was making people sick with diarrhea and cholera.

Bangladeshi children celebrate a bottle of clean water.

In the 1970s, UNICEF, the World Bank and other agencies led the effort to switch the water supply from surface water to ground water and encouraged the population to dig wells. More than four million wells were dug by western engineers, aid agencies and villagers themselves, and the incidence of waterborne diseases dropped. At about the same time, Bangladesh also started growing a new variety of rice called “boro”—a high-yield crop that is grown during the winter months and nourished by groundwater irrigation. This new rice has helped the country feed its growing population.

But in the early 1990s, people began to develop calluses on the palms of their hands and the soles of their feet—early symptoms of arsenic poisoning, a slow-moving disease that kills people 15 to 20 years after they have been exposed to it. Today, more than 40 million people are drinking arsenic-tainted well water in what has become known as the greatest case of mass poisoning the world has ever known.

Arsenic exists everywhere in nature, often in rock or sediment, and does not cause any health problems because it stays in solid form. The question posed to engineers and scientists was this: Why is arsenic seeping into Bangladesh’s water supply?

Shafiqul Islam was teaching at the University of Cincinnati when he learned about the problem in his native country. In 1999, he visited Bangladesh with a colleague from MIT, Prof. Charles Harvey, to try and understand the nature and extent of the problem. A year later, they received National Science Foundation funding to explore the causes of high arsenic contamination in the Ganges basin. Islam received a Fulbright Fellowship in 2002 and continued to work on the problem. Since coming to Tufts in September as a professor of civil and environmental engineering and the first Bernard M. Gordon Senior Faculty Fellow in Engineering, Islam has continued his research in Bangladesh and on other projects involving water. What Islam and colleagues from MIT and Bangladesh found was that between 80 and 150 feet below the surface, arsenic existed in water in very high concentrations, yet there was little arsenic near the surface and not much at levels below 200 feet.

Shafiqul Islam © Mark Morelli

The reason, he said, is that the ground water table fluctuates greatly, plummeting during the dry season. This fluctuation causes deeper ground water to be replaced by surface water that is rich in organic material, which then mobilizes the insoluble arsenic. Over time, the naturally occurring arsenic was transformed from a solid form into a liquid capable of infiltrating the water supply.

While the allowable standard for arsenic in the United States is 50 parts per billion, in many of the Bangladeshi wells, arsenic levels reach 500 to 1,000 parts per billion—and some contain 2,400 parts per billion.

“A quick solution would be to dig wells 400 feet or deeper, where there is virtually no arsenic. But it’s very expensive,” said Islam. Most affected Bangladeshis continue to use well water because there simply are no other sources.

While his area of expertise is water, Islam’s work reaches far beyond the technical aspects of his discipline. Interested in how policy affects water, health and diplomacy, he said he was drawn to Tufts because it encourages collaboration among researchers and schools. In fact, when he visited the university last spring, someone handed him an article that appeared in the university alumni magazine. It was “A University Poised” by President Lawrence S. Bacow, and it made a lasting impression on him.

“The president,” he recalled, “offered his vision of what he thinks Tufts should be, and he said that new discoveries will be at the interfaces of disciplines. My main motivation for coming to Tufts is that I think the university has taken significant steps toward bringing different disciplines together.”

He noted that Tufts has a “strong engineering school” whose dean, Linda Abriola, specializes in water, but there are other strong schools where he expects to be collaborating with researchers. He noted in particular the medical and nutrition schools as well as the Fletcher School of Law and Diplomacy. And, he added, Tufts encourages people from different disciplines to work together.

Shafiqul Islam, left, and a graduate student watch MIT colleague Charles Harvey simulate ground water rich in organic material by injecting it with molasses.

“You look around the United States,” he said, “and there is much discussion of interdisciplinary pursuits, but unless you have an alignment of aspirations of faculty, administration and students, it won’t work. My sense is that it’s happening here.”

In addition to continuing his work in Bangladesh, Islam is also working on a project involving the use of satellites and other remote sensors to measure rainfall and evaporation and study how global warming may be affecting the distribution of water around the globe.

At the University of Cincinnati, Islam was the director of the Earth Systems Science Program, an interdisciplinary graduate program involving more than 20 faculty from three different colleges. He also developed international partnerships with faculty and students at MIT as well as the Bangladesh University of Engineering and Technology, the University of Tokyo and the Swiss Federal Institute of Technology.