New research aimed at identifying which US neighborhoods face increased exposure to toxic PFAS “perpetual chemicals” found that those living near Superfund sites and other major industrial polluters, or in areas with limited access to fresh food, tended to have higher levels of dangerous compounds in their blood.
The study looked at hundreds of people living in Southern California and found that those who didn’t live within half a mile of a grocery store had 14 percent higher levels of PFOA and PFOS — two common PFAS compounds – in their blood than those who do.
Meanwhile, those who live within three miles of a Superfund site — a site contaminated with hazardous substances — have up to 107 percent higher levels of some compounds, and people who live near a facility known to use PFAS, show significantly higher levels in the blood.
The findings highlight how the built environment in low-income neighborhoods presents multiple pathways of exposure to PFAS, said Sherlock Li, a postdoctoral researcher at the University of Southern California. The decisions are not easy, he added.
“It’s a tough question because you can’t just tell people to move or buy air filters and water filters and eat healthy food,” Li said. “We hope the government sees the analysis and takes action … because it is more cost-effective to reduce pollution at source.”
PFAS are a class of about 15,000 compounds that are commonly used to make products that are water, stain and heat resistant. They are called “permanent chemicals” because they do not break down and accumulate naturally, and have been linked to cancer, kidney disease, liver problems, immune disorders, birth defects and other serious health problems.
The study also found that people living in neighborhoods with PFAS-contaminated water had 70% higher blood levels of PFOS and PFOA, although there was no link between some other compounds.
Researchers say diet is likely a contributing factor to higher rates in neighborhoods with limited access to fresh food. Previous research has found that processed and fast foods that are more readily available in these neighborhoods tend to contain higher levels of PFAS — chemicals typically added to resist moisture and grease in fast food packaging and take-out containers. Conversely, eating a diet with more fresh foods can help lower blood levels of PFAS.
Although the Food and Drug Administration announced last year that PFAS compounds are no longer approved for use in paper food packaging produced in the US, the chemicals may still be on imported packaging or in plastic containers.
Packaging is among the “key sources” of elevated levels in neighborhoods, Li said, but the solution is partly structural — improving access to fresh food with more grocery stores or community gardens would also benefit from lowering PFAS levels.
Some study participants lived near several former Air Force bases and a metal plating facility that are now PFAS-contaminated Superfund sites.
The link between the site’s groundwater and drinking water is tenuous, and the authors suggest that the higher blood levels of PFAS around Superfund sites and industrial facilities that use the chemicals largely stem from air pollution. PFAS can be volatile, i.e rises into the air from a contaminated area or may land on dust and then be inhaled or swallowed.
“We need to be more holistic to reduce exposure to water, food, soil air — all of them,” Li said.