Fluorine mass balance analysis of selected environmental samples from Norway

The presence of unidentified organofluorine compounds (UOF) has been investigated in recent publication, but their environmental occurrence is still poorly understood. Fluorine mass balance analysis was performed on environmental samples from lake Mjosa and river Alna (surface water (n = 9), sediment (n = 5) and fish liver (n = 4)) and sewage samples from Oslo (n = 5), to reveal to the fraction of UOF. In samples that had extractable organofluorine (EOF) concentrations above the limit of detection (LoD), more than 70% of their EOF could not be accounted for by the 37 PFAS monitored in this study. The surface water samples from lake Mjosa had EOF concentrations several times higher than what has been reported elsewhere in Nordic nations. The flux of EOF in river Alna and selected sewage pipes revealed that it was 1-2 orders of magnitude higher than the flux of the measured PFAS. The elevated concentrations of EOF in all samples pose a potential health and environmental hazard, as their composition remains mostly unknown.

Automated summary

This study investigated the presence of unidentified organofluorine compounds (UOF) in environmental samples from lake Mjosa, river Alna, and sewage samples from Oslo. The findings revealed high concentrations of UOF in these samples, posing a potential health and environmental hazard due to their mostly unknown composition.