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Who is most at risk of forever chemicals in their drinking water?

As per- and polyfluoroalkyl substances (PFAS), colloquially known as “forever chemicals,” increasingly become a household phrase, more people are asking the question, who is most at risk? PFAS have been detected in drinking water across the country, with researchers from the Environmental Working Group (EWG) estimating that over 200 million people are exposed to tap water with some detectable amount of PFAS.

Some areas may be at greater risk than others, though. While a long-term goal should be to eliminate all PFAS exposures, certain communities with the highest levels of contamination don’t have time to wait and need immediate solutions. How can we identify these communities? Research has shown that some PFAS “hotspots” are related to known sources such as industrial manufacturing sites, airports, and military training sites across the country, but efforts to map other potential PFAS sources nationwide have shown that there is still a lot we don’t know.  

The state of Colorado, for example, proactively surveyed and mapped 193 sites with known or suspected presence of PFAS across the state, including domestic wastewater plants and facilities that store or use PFAS-containing materials such as aqueous film forming foam (AFFF) used in firefighting. However, estimates of the number of suspected sites across the country, drawn from federal databases, suggests that there could be over twice as many sites where PFAS are used or released in Colorado than what the state survey showed, with 501 possible sites—and even that number might be low. Recent data suggests that there may be thousands of potential PFAS discharge sites in Colorado alone if oil and gas operations are considered, which may use and/or store PFAS in fracking fluids and for fire suppression.

The situation in Colorado is indicative of PFAS releases nationwide—the number of potential industrial sources in the environment far exceeds our current ability to fully evaluate all the risks. And that doesn’t even include the myriad other potential sources of PFAS in the environment, such as agricultural operations where municipal biosolids containing PFAS are applied as fertilizer and the millions of septic systems across the U.S. which can leach PFAS into groundwater.

To better guide our understanding of PFAS risk and prioritize areas that are the most likely to be exposed to unsafe levels, researchers have proposed a framework that takes into account not only the number and density of potential PFAS hazards in an area, but also the surrounding population’s vulnerability to environmental contamination through drinking water.

For example, even in areas with many potential PFAS sources, large water utilities are more likely to be able to implement the advanced and costly water treatment necessary to remove PFAS. Therefore, these areas may be at lower risk than small, rural utilities with nearby sources.

The most vulnerable group of all may be those who get their water from private wells. Over 42 million people across the U.S. get their water from private wells, but well water is not regulated by the Safe Drinking Water Act, meaning that it is up to individuals to make sure their water is safe to drink. Well users have the least access to expensive PFAS testing so they often aren’t aware if their water contains unsafe levels.

More widespread testing is needed to respond to this challenge. Better data on actual PFAS concentrations in groundwater, surface water, and drinking water will help improve our understanding of the relative importance of the thousands of possible sources and clearly prioritize areas that are at greater exposure risk. Under the EPA’s new PFAS Strategic Roadmap, which outlines the agency’s commitments to action in the next three years, we may get more insight into these questions as PFAS testing is expanded to more drinking water systems nationwide, including more small systems than previously tested. Meanwhile, individual states like Colorado are also investing in their own PFAS testing through a grant program for communities across the state that need technical support. At RTI, we are also working to expand our advanced PFAS testing capabilities to private well users across the country so we can prevent PFAS exposures in the areas that need it most.

Learn more about our PFAS research and our collaboration with Indiana University to test well water in North Carolina, Indiana, Minnesota, and Washington at our Clean Water of U.S. Kids website: www.cleanwaterforuskids.org/foreverchemicals.

Disclaimer: This piece was written by Riley E. Mulhern (Research Environmental Engineer) to share perspectives on a topic of interest. Expression of opinions within are those of the author or authors.