ADLM 2025 study finds people in high-exposure areas are more than twice as likely to have elevated PFAS concentrations.
Research presented at ADLM 2025 found that people who live in areas with higher levels of PFAS in their drinking water also have elevated blood levels of these manufactured chemicals.
Highlighting why these so-called “forever chemicals” are a growing public-health concern, researchers say these findings provide support for policies encouraging more PFAS testing and treatment in public water systems.
“Drinking water is one of the most important routes for exposure to environmental contaminants, including PFAS,” says Dr Wen Dui, a member of the research team from Quest Diagnostics who conducted the study, in a release. “This study was the first of its kind to apply the National Academies of Science, Engineering, and Medicine (NASEM) PFAS guidance to study correlation between PFAS in human bodies and drinking water in a large-scale clinical population.”
Diving into PFAS
First developed in the 1940s, PFAS, or per- and poly-fluoroalkyl substances, were designed to resist water, oil, grease, and heat, making them useful in numerous consumer products and across multiple industries. For example, PFAS can be found in non-stick cookware, waterproof clothing, and fast-food packaging, as well as in firefighting foams, aircraft components, medical devices, and construction materials. The substances can enter the public water supply when manufacturers release wastewater into nearby water sources, for example, or when PFAS in landfills leach into groundwater.
Scientists are concerned about possible health consequences of PFAS, which build up in people and the environment over time. For instance, NASEM found evidence of an association between PFAS and adult kidney cancer, decreased infant and fetal growth, abnormally high cholesterol, and a reduced antibody response. The NASEM guidance recommends that anyone with high blood levels of PFAS, defined as a summed total of more than 20 ng/mL of nine key PFAS, receive further testing and reduce their exposure.
“Several federal agencies, including the Centers for Disease Control and Prevention and NASEM, have worked together to summarize evidence, publish guidance, and encourage more clinical PFAS testing,” Dui says in a release. “Quest developed and published a blood test for serum PFAS quantitation of the nine NASEM-recommended analytes to address the critical need for reliable PFAS measurement in clinical laboratories.”
Relationship Between PFAS-Contaminated Drinking Water and Blood Levels
As one of its first steps, the team sought to establish the relationship between drinking water contaminated with PFAS and PFAS levels in people’s blood—which is what this new study accomplishes.
Since the US Environmental Protection Agency monitors the amount of PFAS in public water systems, the researchers were able to pull information from previously collected blood samples to do a geographic comparison by exposure level. They evaluated blood samples taken from 771 individuals who lived in zip codes with high exposure to PFAS through their water and 788 people with low exposure to the substances, ensuring the two groups were otherwise comparable in their age and gender distribution.
They found that 7.1% of the people from zip codes with high-exposure to PFAS had elevated blood levels of PFAS (>20 ng/mL), versus only 2.8% of the people in the low-exposure group—a significant difference. Moreover, the estimated average of combined PFAS in the blood samples was significantly higher in the high-exposure group (9.2 ng/mL) versus the low-exposure group (6.1 ng/mL), as were mean blood levels of each individual PFAS studied.
“Our study found that a higher PFAS level in US public drinking water supply corresponds to higher PFAS serum concentrations in exposed communities,” Dui says, adding that, as a next step, the company hopes to contribute to research on the correlation between PFAS exposure and health outcomes.
