Alexandria Thomas, a PhD student at the University of Kentucky (UK) College of Public Health, is conducting crucial research on an assortment of toxic manmade “forever chemicals” in the area surrounding a toxic waste incineration plant in East Liverpool, Ohio. Her research bridges the gap between geological sciences and public health, addressing the pressing issue of per- and polyfluoroalkyl substances (PFAS) contamination.
Originally from Peachtree City, Georgia, Thomas came to UK as a student-athlete on the cheerleading team. She earned her BA and MS degrees in geological sciences. While writing her master’s thesis, “Field Tests of a UAV-Compatible Spectrometer to Evaluate its Suitability for Detailed Soil Radon Potential Mapping,” she became fascinated by the intersection of geological sciences and public health.
When Thomas returned to UK for her PhD, she had a clear purpose in mind.
“My goal in joining the Biostatistics and Epidemiology program was to increase my knowledge of public health hazards and bridge the gap between geological sciences and public health by participating in geo-health-related research,” she said.
Thomas was introduced to the PFAS contamination project by Erin Haynes, DrPH, the Kurt W. Deuschle Professor of Preventive Medicine and Environmental Health and the chair of the Department of Epidemiology and Environmental Health (EEH). Haynes said Thomas’ background made her an excellent fit for the research project.
Understanding PFAS
Since the 1940s, PFAS have been used in various industrial and consumer products due to their resistance to water, oil, and heat.
“PFAS are typically found in drinking water, soil, and water at/near waste sites, fire extinguishing foam, manufacturing or chemical production facilities that produce or use PFAS, food, food packaging, household products and dust, personal care products, and biosolids,” stated Thomas.
According to the Agency for Toxic Substances and Disease Registry (ATSDR), per- and polyfluoroalkyl substances, often referred to as “forever chemicals” because they are nearly indestructible, have been recognized as a global health threat.
The ATSDR, a federal public health agency of the U.S. Department of Health and Human Services, lists several health risks that epidemiological evidence has associated with exposure to (specific) PFAS, including increases in cholesterol levels, lower antibody response to some vaccines, changes in liver enzymes, pregnancy-induced hypertension and preeclampsia, small decreases in birth weight, and kidney and testicular cancer.
The East Liverpool research
The hazardous waste incinerator in East Liverpool has been accepting PFAS shipments for disposal since 2019.
A fire at the incinerator left Haynes and her team with questions about increased PFAS levels in the soil. Because they had pre-fire and post-fire samples, the team could compare PFAS levels.
Thomas’ research involves digitally mapping and comparing soil samples collected before and after the fire to determine the differences, if any. She employs digital mapping techniques to visualize and analyze PFAS distribution, identifying contamination hotspots and changes. Key PFAS compounds under investigation include perfluorooctane sulfonate, perfluorooctanoic acid, perfluorobutane sulfonate, hexafluoropropylene oxide dimer acid and perfluorononanoic acid.
Although the research team cannot trace the source of the PFAS contamination, they can look for changes and the location of these changes.
“At this moment, I am not sure what the potential sources of PFAS are, especially related to the incinerator. But, using wind direction during and after the fire is helpful in understanding the levels of PFAS we are finding,” Thomas said.
Another challenge is the lack of clear regulatory guidelines or health risk thresholds for PFAS in soils, as most are not regulated by the U.S. Environmental Protection Agency (EPA).
“Although EPA has regulatory guidance for PFAS in water, there are no regulatory guidance levels for PFAS in soil,” she said, which complicates risk assessment and remediation strategies.
Implications of Thomas’ research
Thomas’ research will inform public health and environmental management. By identifying PFAS concentration and distribution in soil, her work contributes to the development of effective mitigation and remediation strategies. Her research also highlights the importance of raising awareness about PFAS and reducing exposure through informed practices.
Haynes, who has been guiding Thomas, praised her contributions.
“It is a joy working with Alexandria on this project,” Haynes said. “She brings her geology expertise to our soil PFAS study in East Liverpool, Ohio. Her knowledge of geospatial analyses and her attention to detail are invaluable. The project is significantly benefiting from her involvement.”
This work is part of a larger ongoing health research study funded by the National Institute of Environmental Health Science. To learn more about the research Haynes is conducting in East Liverpool, visit https://cph.uky.edu/research/projects/cares/east-liverpool.
Research reported in this publication was supported by the National Institute of Environmental Health Science of the National Institutes of Health under Award Number R21ES035322. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.
