Pipes and pumps have improved many people's access to water in developing countries, but their water may still be contaminated. Growing awareness of this situation has led to the inclusion of a new criterion, water quality, in the Sustainable Development Goals for water access accepted by the U.N. General Assembly in September. Stanford researchers have launched a major study of the health impact of access to chlorinated water in Bangladesh, funded by the World Bank.

A Bangladeshi Boy

A Bangladeshi boy, a vivacious chatterbox, appeared to be roughly three years old. “The first thing he did was talk to me about his book,” says Stanford graduate student Shreyan Sen, who encountered the boy during fieldwork in Dhaka together with Stanford doctoral student Jenna Swarthout. “His next move was to steal my glasses and put them on his face. Still, he wasn't exactly selfish. He plopped his hat on my head as some sort of barter for the glasses,” Sen added.

A glint in the boy’s eye and curiosity in his voice signaled precocity, Sen says. “He has plenty of practice charming the many family members and neighbors who care for him, and who create the strong family bonds in communities like his.

Sen and Swarthout may help ensure that the boy develops to his full capacity. He lives in a slum of Dhaka, the capital of Bangladesh. The city’s regional population of 17 million approaches that of the greater Los Angeles area, crammed into one-tenth the space. Ninety-five percent of Dhaka’s slum communities share water from a common point such as a water hand pump. And 97 percent of those points are fouled by sewage and other contaminants.

At less than five years of age, the boy is part of a population that is extremely vulnerable to public health risks, particularly waterborne diseases. The boy’s drinking water could undermine him with illness and derail his curiosity, notes Sen, a student in Stanford’s civil and environmental engineering department. Sen helped to evaluate the health effects of chlorine-based water disinfection systems installed at communal water points. “We have learned to protect some of the world's children against waterborne disease,” he says. “But that protection is limited.”

Linking Childhood Health to Development

Many children who live in conditions of low water quality, poor sanitation and hygiene ingest large quantities of fecal bacteria. These organisms may affect child growth and development according to Jean Humphrey, a professor at the Johns Hopkins Bloomberg School of Public Health. “At a population level, these conditions may cause massive losses in cognitive and economic capacity such as how well children do in school, how many years they attend school, and adult incomes,” says Humphrey.

Sen, Swarthout and other Stanford researchers are working to counter those risks through the Lotus Water project of Stanford’s Water, Health & Development program. Stanford environmental engineer Amy Pickering leads the research, as a research associate and lecturer with the Stanford Woods Institute for the Environment, and a senior fellow with the Stanford Center for Innovation in Global Health. Pickering is working in collaboration with Professor of Medicine Stephen Luby, a Woods senior fellow. During this research phase, Sen and Swarthout helped to conduct a widespread evaluation of the health benefits generated by water disinfection technologies that are installed on shared water taps.

The study is taking place in two low-income communities in Dhaka, Bangladesh, in partnership with the International Center for Diarrheal Diseases Research, Bangladesh.

The researchers have identified 100 study sites, half of which will have a chlorine doser attached to their taps. For the next year, the researchers will monitor chlorine residuals and bacteria contamination in the water. They will also monitor child diarrheal illness and child weight in both groups. These observations will help them assess impacts of the chlorine dosers on water quality and child health. 

Writing the Future

Sen describes reaching into his pocket and giving the boy his pen. “I think of our work as helping ensure that this bright, vivacious child gets a real shot at writing something important with that pen one day.”

The World Bank Strategic Impact Evaluation Fund (SIEF) provided funding for this study. The Lotus Water Project is a collaboration between Stanford University and the International Center for Diarrheal Diseases Research, Bangladesh.