Anasthasia Shilov

A recent Yale-affiliated study discovered how per- and polyfluoroalkyl substances — a group of harmful chemicals also known as PFAS — affect maternal hormones crucial to fetal development.

Commonly found in food packaging such as pizza boxes, PFAS are known to cause cancer, liver damage and decreased fertility. Published in Environmental Health Perspectives on Nov. 12, the study found that pregnant women had abnormal fluctuations in maternal thyroid hormones during early pregnancy when exposed to PFAS.

Zeyan Liew, the study’s senior author and a School of Public Health assistant professor of epidemiology, said the study is the first to establish a connection between PFAS and levels of thyroid hormones in the first trimester of pregnancy.

The effect of PFAS on the environment and body has gained recent attention from academics and policymakers alike. Last year, the Environmental Protection Agency stated that there are more than 4,000 types of PFAS found in the environment. In Connecticut, Gov. Ned Lamont has created the Connecticut Interagency PFAS Task Force and Rep. Rosa DeLauro has called for a ban on PFAS in food packaging.

Liew said the team recruited a cohort of women early in their pregnancies and took weekly measurements of thyroid hormones levels to account for their subtle changes over time.

According to Liew, his research — which focuses on the harmful effects of PFAS on neural development in infants — is part of a larger effort from Yale scientists to understand PFAS and communicate their harms to the public.

Krystal Pollitt, a School of Medicine assistant professor of epidemiology, said she is working with postdoctoral researcher Jeremy Koelmel on software that helps to identify the chemical structures of PFAS. According to Koelmel, the software will be released to the public for free as an open source project.

John Fortner, an associate professor of chemical and environmental engineering, is collaborating with researchers at Brown University and Auburn University on a project that aims to get rid of PFAS in groundwater. The project has received a grant from the Department of Defense.

Jaehong Kim, the Yale department chair for chemical and environmental engineering, said it is extremely challenging to destroy PFAS that have already made their way into the environment and pose a threat to human health.

PFAS have been used in various industries around the world since the 1940s, according to the EPA website.

David Guo |