Read the full article by University of California, Riverside (Science Daily)

“Under anaerobic conditions, a carbon-carbon double bond is crucial for the shattering the ultra-strong carbon-fluorine bond by microbial communities. While breaking the carbon-carbon bond does not completely degrade the molecule, the resulting products could be relayed to other microorganisms for defluorination under in aerobic conditions.

The achievement builds upon prior work by the same researchers, who were the first to report successful microbial defluorination of a fully fluorinated PFAS structure by replacing carbon-fluorine bonds with carbon-hydrogen bonds.

Per- and polyfluoroalkyl substances, or PFAS, are a group of over 9,000 chemicals used in countless industrial processes and commercial products since the 1940s. As a result, PFAS have found their way into the water cycle and are now found in virtually every water source. These chemicals contain a bond between fluorine and carbon atoms that is the strongest single bond known, rendering PFAS non-biodegradable and resistant to conventional water treatment methods. They wind up in the tissues of organisms, including humans, where they have been associated with some types of cancer, thyroid and liver problems, and likely other, still poorly understood, health problems.

In an earlier paper, Yujie Men, an assistant professor of chemical and environmental engineering, and her colleagues reported using anaerobic microbial communities often used for dechlorination to degrade two specific PFAS, including one fully fluorinated, or perfluorinated, structure.

The new paper takes this research a step further by showing that the point of entry for the anaerobic microbes was a double bond between carbon atoms located next to the carboxyl group of the FCA molecules. Trifluoromethyl branches on the double bond could further enhance the biodegradability.”…