When pregnant women drink water that comes from wells downstream of sites contaminated with PFAS, known as “forever chemicals,” the risks to their babies’ health substantially increase , a new study found. These risks include the chance of low birth weight, preterm birth and infant mortality.
Even more troubling, our team of economic researchers and hydrologists found that PFAS exposure increases the likelihood of extremely low-weight and extremely preterm births, which are strongly associated with lifelong health challenges.
What wells showed us about PFAS risks
PFAS, or perfluoroalkyl and polyfluoroalkyl substances, have captured the attention of the public and regulators in recent years for good reason. These man-made compounds persist in the environment , accumulate in human bodies and may cause harm even at extremely low concentrations .
Most current knowledge about the reproductive effects of PFAS comes from laboratory studies on animals such as rats, or from correlations between PFAS levels in human blood and health outcomes .
Both approaches have important limitations. Rats and humans have different bodies, exposures and living conditions. And independent factors, such as kidney functioning , may in some cases be the true drivers of health problems.
We wanted to learn about the effects of PFAS on real-world human lives in a way that comes as close as possible to a randomized experiment. Intentionally exposing people to PFAS would be unethical, but the environment gave us a natural experiment of its own.
We looked at the locations of wells that supply New Hampshire residents with drinking water and how those locations related to birth outcomes.
We collected data on all births in the state from 2010 to 2019 and zoomed in on the 11,539 births that occurred within 3.1 miles (5 kilometers) of a site known to be contaminated with PFAS and where the mothers were served by public water systems. Some contamination came from industries, other from landfills or firefighting activities.
