By Hayley Britton
The Vanderbilt Center for Sustainability, Energy and Climate (VSEC) recently welcomed Alexis Temkin, a researcher from the non-profit advocacy Environmental Working Group, to discuss the increasing use of “forever chemicals” and ways to better regulate them.
Temkin is an expert on the chemicals – known as PFAS for per- and polyfluoroalkyl substances – that are found in consumer and industrial products, such as cleaning supplies, cookware, and food packaging. Commonly referred to as “forever chemicals,” PFAS do not easily disintegrate in the environment, and therefore can contaminate water supplies. Exposure to these chemicals, even at low levels, poses severe health risks, including cancer, liver and thyroid damage, and complications with fertility and fetal development.
Temkin delivered her lecture on February 13, 2025, as a guest speaker in a Planetary Health Approach to Resource Sustainability class funded by VSEC. The course is co-taught by Yolanda J. McDonald, assistant professor of human and organizational development and principal investigator at Vanderbilt’s Drinking Water Justice Lab, and Kayla M. Anderson, Community Action and Research Ph.D. candidate. A class taught by Zdravka Tzankova, associate professor of the practice in climate studies, joined the lecture.
“Widespread contamination is pervasive in produce,” said Temkin, noting an increase in PFAS in agricultural pesticides in recent years. “It causes unintended consequences, potentially because of how we think about these chemicals.”
She said the United States has approved 66 PFAS for use in pesticides compared to a country like Denmark, which only allows 11. Additionally, she pointed out that the USDA Pesticide Data Program found from 2017 to 2023, common produce items, such as kale, grapes, and peppers, each contained six to eight active PFAS.
One particularly concerning side effect of PFAS is trifluoroacetic acid (TFA), which is difficult to remove from water sources. Temkin said TFA concentrations are particularly high in agricultural areas.
While some regulatory measures exist for PFAS, Temkin said the original bans on the chemicals were due to their extreme toxicity, particularly their harmful effects on the human immune and reproductive systems. She emphasized comprehensive monitoring and testing to better regulate the growing problem. For instance, she said there should be federal regulations at the time of pesticide approval, and better disclosure of pesticide ingredients.
“There’s not a one-size-fits-all approach for regulating this problem,” she said. “The only way to know is by testing for it.”
McDonald and Hiba Baroud, associate professor of civil and environmental engineering and director of VSEC, are co-leading an effort to predict and monitor PFAS in Tennessee’s community water systems and to identify communities at risk for contamination.
In response to a 2024 regulation from the U.S. Environmental Protection Agency, the Tennessee Department of Environment and Conservation (TDEC) has awarded the team an 18-month, $352,944 grant.