Fluorine-free foams exhibit incomplete aerobic and anaerobic biodegradation, create redox-specific byproducts and shift microbial communities.

The phaseout of per- and polyfluoroalkyl substances (PFAS) in firefighting foams has motivated the adoption of fluorine-free foams (F3), yet their environmental fate remains poorly understood. This study provides the first comprehensive assessment of F3 biodegradation under both aerobic and anaerobic conditions, combining modified OECD protocols, high-resolution mass spectrometry (HRMS), and microbial community profiling to elucidate surfactant degradation pathways, byproduct formation, and ecological impacts. Aerobic systems achieved greater than 80% bulk dissolved organic carbon (DOC) removal for two commercial F3 formulations within 28 days, yet targeted analyses revealed persistent, hydrophobic surfactants (, ethylene glycol dodecyl ether, EGDE) in sludge phases (2-5 μg L) and transient byproducts like short-chain glycol ethers.

Evaluation of PFAS extraction and analysis methods for biosolids.

Per- and polyfluoroalkyl substances (PFAS) in the environment is a growing concern leading to a focus on PFAS occurrence in biosolids, a byproduct of wastewater treatment processes, often applied to improve soil health. This led to the need for analytical method development for assessing PFAS in biosolids. This study compares three methods for PFAS quantitation, evaluating solvent extraction, clean-up techniques, and final injection solvents.

Application of Gaussian mixture models to quantify the upper background threshold for perfluorooctane sulfonate (PFOS) in U.S. surface soil.

Studies on the occurrence and environmental distribution of per- and polyfluoroalkyl substances (PFAS) have clearly demonstrated their ubiquity in surface soil as a result of historic and ongoing emissions from various manufacturing and industrial activities worldwide. Given global efforts to characterize and mitigate risk from point source-impacted sites, there is, thus, an urgent need to quantify nonpoint source threshold concentrations (i.e.