Researchers are struggling to catch up with recently identified and evolving subgroups of PFAS, but two new studies from North Carolina scientists indicate progress is being made.
PFAS, or per- and polyfluoroalkyl substances, are a class of toxic and pervasive chemicals colloquially referred to as forever chemicals for their inability to naturally break down in the environment and human body. These chemicals have been used in manufacturing since the 1940s and are found in a number of household products today. Locally, a number of ongoing lawsuits accuse chemical manufacturer Chemours and its predecessor, DuPont, of knowingly contaminating the Cape Fear River and surrounding environment with PFAS.
While older types of PFAS have been phased out of manufacturing processes because of studies documenting their toxic effects, chemical companies have turned to newer and more obscure PFAS to take their place. For example, in 2009 DuPont decided to substitute PFOA, possibly the most well-known of the per- and polyfluoroalkyl ether acids family, for GenX.
Research on these newer classes of PFAS and their health effects is scant compared to studies on other, more familiar types of PFAS chemicals, but scientists are developing new approaches to bridge the gap in knowledge.
Eight new PFAS found
Part of the work around expanding knowledge of PFAS is identifying the new chemicals that have been developed, a challenge recently taken up by researchers within UNC-Chapel Hill’s College of Arts and Sciences. In a recent study led by Erin Baker, an associate professor of chemistry at UNC-CH, a team of researchers was able to develop a new method to identify previously unknown PFAS from old samples of water from the Cape Fear River in 2016. The study was published in Science Advances on Oct. 25.
Using novel testing methods, the UNC researchers were able to find 11 types of PFAS that had not been previously detected in the river before — and eight PFAS that had never been seen outside of a lab before.
“Current testing methods used by the EPA can only find the PFAS that we already know exist,” Baker said. “That means we have to rely on chemical companies to provide a list of what they manufacture and hope those samples are comprehensive.”
Baker indicated the discovery of a new testing method to find PFAS can help researchers and the public learn about PFAS that chemical companies have not listed publicly.
“If industries create molecules that they don’t tell the public about, and we only test for the molecules they do tell us about, we could be missing things,” Baker said. “We need to use non-targeted testing to have more information on what our communities are being exposed to.”
New findings in GenX Exposure study
Researchers who are part of the GenX Exposure Study also announced new findings this week relating to testing methods and detection of PFAS. The study used well water and blood samples taken in 2019 from 84 private wells and 153 people within six miles of the Fayetteville Works plant.
The study, published Jan. 10 in the Journal of Exposure Science & Environmental Epidemiology, showed that the PFAS compounds were released into the environment via air and wastewater from the Fayetteville Works manufacturing plant, and led to contamination in both groundwater and wells. The finding strengthens previous research on air contamination pathways from the Chemours plant.
Another key finding from the study is that GenX and four emergent and low-molecular types of PFAS (PMPA, PEPA, PFO2HxA, PFMOAA) were not seen frequently in study participants' blood, despite being identified as chemicals detected frequently and at highest concentrations in the residents’ wells.
Researchers concluded that testing methods might need to be adjusted to determine a person’s exposure level to these lesser-known types of PFAS. Accurate exposure testing, they concluded, will also pave the way for studies on the toxicity of these newer PFAS, of which little is known about their effects.
“Blood levels of a chemical across a population are often used to characterize exposure,” Nadine Kotlarz, the study’s corresponding author, said. “Without blood levels, we will need to estimate exposure to PFAS such as GenX another way in order to study their potential health effects.”
Contact Evey Weisblat at eweisblat@cityviewnc.com or 216-527-3608.
To keep CityView Today going and to grow our impact even more, we're asking our committed readers to consider becoming a member.
