Electric Field Potentially Enhances the Defluorination of 6:2 Fluorotelomer Alcohol (6:2 Ftoh) in Soil Through Increasing the Relative Abundance of Dechloromonas

Electrokinetic bioremediation has shown promise in the degradation of recalcitrant contaminants, but is yet to be attempted with poly- and perfluoroalkyl substances (PFAS). This study investigated electrokinetic biodegradation of 6:2 fluorotelomer alcohol (6:2 FTOH) in hydrated soil. Results suggest that the presence of electric fields led to a 10-fold increase in the F - detected (9.6 and 1.0 F - /mol FTOH under electrokinetic and non-electric conditions respectively). However, no significant differences were observed in the generation of common metabolites, which, in conjunction with the enhanced F - release, could suggest unidentified metabolites and degradation pathways. Exposure to an electric field and 6:2 FTOH also yielded more homogenous bacterial communities, especially under the highest evaluated voltage of 2 V/cm. The relative abundances of four key genuses were enriched from <0.1% to 5-10% after six weeks, among which the relative abundance of Dechloromonas showed a statistically significant correlation with the F - concentrations, suggesting possible involvement in the defluorination of 6:2 FTOH. This study provides the first evidence for the potential viability of electrokinetic remediation in PFAS degradation and the possible involvement of Dechloromonas .