Credit: Environmental Working Group/Social Science Environmental Health Research Institute/Northeastern University
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It’s not every year that water chemistry scores a spot at the movie theater. The November release of Dark Waters, a film starring Mark Ruffalo as a lawyer investigating water contamination in West Virginia, crowned a year of expanded public awareness of PFAS, the family of nonpolymer per- and polyfluoroalkyl substances that persist in the environment and are linked to health problems. Meanwhile, an ever-growing list of contaminated sites drew increased regulatory scrutiny as scientists raced to understand the chemicals and test potential treatments.
In 2019, scientists studying the persistent pollutants uncovered new information about their impact, how they cycle in the environment, and what it will take to get rid of them. Development continued on a battery of potential treatment methods, including new adsorbents that better target PFAS and destructive technologies aimed at demolishing the strong C–F bonds that make PFAS so persistent. Chris Higgins, who studies emerging contaminants at the Colorado School of Mines, says he expects this “every tool on the table” approach to continue.
“It’s such a big liability; you don’t want to put all your eggs in one basket,” he says.
After a few years in the pipeline, some technologies have cleared important milestones on the road to large-scale use. For example, a plasma reactor that uses electricity and argon gas to generate highly reactive species that can break down PFAS completed a field test in September, treating hundreds of liters of contaminated water at Wright-Patterson Air Force Base in Ohio.
“We’re starting to be able to bring some of these technologies to the table, where there was a lot of skepticism before” about whether PFAS could be treated effectively, says Michelle Crimi, who studies water remediation methods at Clarkson University.
Credit: Clarkson University
Researchers used a plasma reactor to break down PFAS molecules in contaminated water during a field test this year.
And this year, scientists reported that a microbe found in a New Jersey wetland could detoxify PFAS, potentially offering a cheaper and more sustainable approach to treating contaminated water than energy-intensive systems like the plasma reactor.
The difficulty in removing PFAS from the environment has drawn attention to how we dispose of contaminants and their fate in the environment, Crimi says. She hopes the experience will prompt society to focus more on preventing pollution in the first place. The year 2020 could shape up to be another interesting one for PFAS, as federal regulators continue to grapple with whether and how to regulate these compounds.
Higgins says he’s encouraged to see a wealth of new information brought to light about the compounds.
“It’s actually a pretty exciting time to be following all the research,” he says.