Microbial degradation of PFAS for remediation of contaminated soil and groundwater (bioPFAS)

Per- and polyfluoroalkyl substances (PFAS) are very challenging to remediate and remove from contaminated soil and groundwater. While there is ongoing research on the topic, there is still a lack of cost-efficient techniques for in-situ or on-site PFAS degradation, largely due to the extreme recalcitrance of perfluoroalkyl acids (PFAAs), which are often the end-products of environmental PFAS transformations. Microbial degradation is a key process for the removal of many organic contaminants from the environment. There is also growing evidence from laboratory studies that under the right conditions microbial degradation of PFAS, including PFAAs occurs, indicating that microbial degradation potentially can be developed into a useful PFAS remediation method. At the same time, there is a lack of knowledge about microbial PFAS-degradation processes and the organisms involved. Improved knowledge of PFAS biodegradation is also necessary to better understand PFAS mass transport from contaminated hotspots.Here, the aims, methods and preliminary results of a newly started research project: “Microbial degradation of PFAS for remediation of contaminated soil and groundwater” (bioPFAS) are presented. The project aims at investigating how conditions for microbial degradation can be stimulated at PFAS-contaminated sites, the degree and rates of degradation that can be achieved, the main environmental factors governing degradation and the organisms involved. Systematic laboratory studies will be performed using a large number of incubations to identify and characterize PFAS-active microbial strains and consortia as well as governing environmental factors. PFAS transformations will be quantified and characterized and the potential for field application will be investigated first in soil columns and subsequently in a small field demonstration test. Geochemical and PFAS-transport models will be used to further investigate the feasibility of microbial PFAS degradation and any associated risks.