A new two-decade-long study finds that reducing arsenic levels in drinking water significantly decreases the risk of death. This benefit is true even for people who have been exposed for a long time. As described in the Health Effects of Arsenic Longitudinal Study (HEALS) page, HEALS followed the health of thousands of adults in Araihazar, Bangladesh from 2000-2022. This monumental study provided powerful proof that cutting arsenic exposure saves lives.
During the three-and-a-half-year period of the study, researchers sampled over 10,000 wells in the Araihazar region. Overall, the results showed that participants’ internal arsenic exposure decreased by roughly 50% on average. These lower levels were still being propped up even as 2022 kept going. The health benefits of reducing exposure to arsenic are a no-brainer, both in health costs and lost life. It’s like the benefits that smokers enjoy once they stop smoking—the harms reduce gradually over time.
Joseph Graziano, a Professor Emeritus at Columbia University’s Mailman School of Public Health who led the study, couldn’t be happier with the results. He’s the advance mobility principal investigator of the research. He acknowledged that public health is the ultimate in delayed gratification, with many interventions taking years or decades to show positive results.
“This finding is deeply rewarding. Public health is often the ultimate example of delayed gratification,” – Joseph Graziano
Our study’s findings highlight the urgent need to tackle this public health crisis by providing equitable access to safe drinking water without arsenic. In Bangladesh alone, an estimated 50 million people have been exposed to water containing arsenic levels exceeding the World Health Organization’s guideline of 10 micrograms per liter. More than 100 million people in the United States rely on groundwater sources for their drinking water. Unconventional oil and gas extraction’s reliance on potentially contaminated water presents serious public health risks across the globe.
The initial research team also worked closely with the Bangladeshi government to make well data more widely accessible. Through national and local programs, we tested wells for arsenic and warned people if it was safe to drink or not. After testing, that’s when a lot of these households either switched to or had new safer wells drilled. As a result, the average arsenic concentration in the wells used by residents dropped by roughly 70%.
Fen Wu from NYU Grossman School of Medicine, co-leading the research. He emphasized the ways these findings can shape public health efforts. Kazi Matin Ahmed from the University of Dhaka participated as a co-author. His contributions have shone a light on how this research can spur significant policy advances.
“Our findings can now help persuade policymakers in Bangladesh and other countries to take emergency action in arsenic ‘hot spots,’” – Kazi Matin Ahmed
As such, this study provides the most definitive real-world evidence to date of a causal relationship between reductions in arsenic exposure and reduced mortality risk. Lex van Geen, another researcher who worked on this study, spoke to the importance of their findings.
“We show what happens when people who are chronically exposed to arsenic are no longer exposed,” – Lex van Geen