Reducing the risk of “forever chemicals” in Tennessee’s drinking water

By Jenna Somers

A transdisciplinary team at Vanderbilt University seeks to identify Tennessee communities at risk of exposure to toxic man-made chemicals in their drinking water.

In response to a 2024 regulation from the U.S. Environmental Protection Agency, the Tennessee Department of Environment and Conservation (TDEC) has awarded an 18-month, $352,944 grant to Yolanda J. McDonald, assistant professor of human and organizational development and principal investigator at Vanderbilt’s Drinking Water Justice Lab, to lead a transdisciplinary team to support TDEC’s efforts to predict and monitor toxins in Tennessee’s community water systems and to identify communities at risk for contamination.

The chemicals—known as PFAS for per- and polyfluoroalkyl substances—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.

Given these risks, in April 2024, the EPA finalized the National Primary Drinking Water Regulation establishing legally enforceable maximum contaminant levels for six PFAS chemicals in drinking water. Public water systems must complete initial monitoring by 2027 and implement solutions to reduce PFAS levels by 2029.

The Vanderbilt-led project, “PFAS Risk in Tennessee Drinking Water Supply: A Data-Driven Risk-Informed Approach to Identify Communities At-Risk to PFAS Exposure,” brings together researchers from Peabody College of education and human development, the School of Engineering, and the Vanderbilt Institute for Spatial Research at the College of Arts and Science to complete two primary goals:

• To develop an evidence-based approach that uses machine learning models to monitor and predict PFAS chemical levels in Tennessee’s drinking water in compliance with the EPA regulation
• To identify small, disadvantaged, and rural communities whose community water systems have PFAS contamination, so that they can receive funding from the Emerging Contaminants in Small or Disadvantaged Communities grant program to reduce toxin levels

The team plans to develop four machine learning models to predict PFAS contamination levels statewide and across West, Middle, and East Tennessee. They will also create a geospatial assessment tool to analyze PFAS compounds in vulnerable communities and provide TDEC with a project summary report.

The geospatial assessment tool will be informed by 16 drinking water justice indicators focused on socio-economic status, race and ethnicity, age, education levels, and more, as well as four distinct types of vulnerable communities identified by state and federal policies and the Appalachian Regional Commission.

“Our team’s critical data and tools will help TDEC identify communities across Tennessee to understand whether and to what extent they are exposed to PFAS contamination and empower them to access the necessary resources to remove these toxins,” said McDonald. “The Drinking Water Justice Lab has been conducting research in collaboration with TDEC, the Tennessee Department of Health, and the Tennessee Association of Utility Districts for several years, and we are eager for the potential for our working group to do even more to help protect the health of Tennesseans.”

In addition to McDonald, the project leaders are Hiba Baroud, associate professor of civil and environmental engineering and director of the Vanderbilt Center for Sustainability, Energy, and Climate (VSEC); Paul Johnson, research assistant professor of civil and environmental engineering; Natalie Robbins, research analyst in the Department of Anthropology and the program manager and geospatial lead at the Vanderbilt Institute for Spatial Research, and Sriya Jonnakuti, research assistant.

The grant also provides immersive research learning experiences for Ferna Alvarez-Carrascal, Ph.D. student in Earth and environmental sciences, and Vera Powell, second-year student double majoring in environmental sociology and law, history, and society and minoring in chemistry.

This study continues the original research of Aakash Manapat, BA’24, McDonald’s former student advisee. In 2021, he was supported by the Vanderbilt Undergraduate Summer Research Program to co-develop the original machine learning model using the Kentucky data to predict the presence of PFAS contaminants in Tennessee’s community water systems. The Drinking Water Justice Lab now has access to Tennessee PFAS data to refine the model. Manapat will continue to consult with this project team.