Scrubbing Earth of per- and polyfluoroalkyl substances, known as PFAS or forever chemicals, could eliminate a long list of problems for people and the planet. Used for decades in everything from nonstick pans to firefighting foams, PFAS have been linked to fertility challenges, developmental delays, cancer, and reduced immune response. Their strong bond between carbon and fluorine makes them very difficult for the environment to break down.
PFAS are everywhere. They spew from factories and slough off products into water during normal use, and scientists have found them in everything from human blood to Antarctic snow. One 2022 report found that 89% of the US population had PFAS above two nanograms per milliliter of blood plasma, a common threshold for potential adverse health effects, and 9% had passed the riskier level of 20 nanograms per milliliter. New compounds are still being created and used, with more than 12,000 identified, while much cleanup research focuses on only a small handful.
Cleansing PFAS-contaminated soil is in its infancy, but pulling the chemicals out of water systems can prevent further buildup. There are two approaches: trap or destroy. Reverse osmosis, which pushes water through supertight filters, is useful for point-of-use cases like kitchen sink filters. For large-scale removal at water treatment facilities, techniques such as foam fractionation, which uses bubbles to capture PFAS, are being explored. Trapping is imperfect, however, because it leaves behind PFAS-filled brine that must be properly destroyed, an expensive and energy-intensive process.
Jack Huang, a professor of crop and soil sciences at the University of Georgia, is testing electrochemical degradation, which uses electrodes to break the bonds holding PFAS together. The method destroyed more than 90% of PFAS mass in tests and has been licensed by the engineering consulting firm AECOM. Policy also matters: the EPA's PFOA Stewardship Program helped slash releases of perfluorooctanoic acid by 95%, and Minnesota, Maine, and New Mexico have passed bans on PFAS in products like cookware and dental floss. Scientists are making progress, but it will be wasted unless we turn off the tap.
Source: MIT Technology Review · Summarized by HeadlinesBriefing