To Örebro University

Anthropogenic organofluorine, particularly per-and polyfluoroalkyl substances, has been widely detected in aquatic environments for decades. Yet, previous studies have revealed a substantial amount of unidentified organofluorine, posing challenges for environmental and human exposure risk assessment.

This thesis focuses on extractable organofluorine (EOF) analysis via combustion ion chromatography (CIC), with an emphasis on optimization of extraction methods, critically evaluating its utility and identifying compounds in water matrices (wastewater, surface water, and drinking water). Liquid chromatography–high resolution mass spectrometry (LC-HRMS) screening combined with oxidative sample treatment was used to identify previously unknown organofluorine.

Results illustrated variability in organofluorine composition and contrasting EOF-CIC signatures across water types. Inorganic fluorinated compounds, hexafluorophosphate and tetrafluoroborate, were co-extracted and dominated the fluorine mass balance in some tap water and industrial sewer samples, challenging the assumption that the method is specific to organofluorine. Fluorinated pharmaceuticals and transformation products (TPs) dominated the fluorine mass balance of municipal wastewater. The organofluorine load in river water from agricultural areas primarily consisted of fluorinated pesticides and TPs.

The EOF-CIC method was evaluated for PFAS Total assessment and for sewer network source tracking. Its broad coverage provides high value as a screening tool but also complicates interpretations and limits specificity for certain chemical groups. This thesis highlights trade-offs and suggests future developments to enhance the method’s applicability in environmental monitoring.