PFAS in Atmospheric Deposition and Stormwater Baseflow (2025–2026)

There are numerous potential sources of PFAS in stormwater. In addition to land use related sources - such as materials used in urban infrastructure and various human activities - there are indications that PFAS may also originate from contaminated sites, where infiltrated groundwater leaks into stormwater systems and is subsequently transported to receiving waters. Another potential source is atmospheric deposition, both dry and wet (i.e., rain and snow).

This project investigates the occurrence of PFAS in stormwater, baseflow, and atmospheric deposition. The study aims to improve the understanding of how these substances are distributed across different environmental media, particularly in connection with precipitation events.

Several sampling events will be carried out in two to three selected locations. The focus is on collecting composite samples of stormwater during rainfall events, as well as baseflow samples during dry weather conditions (i.e., unaffected by precipitation). In addition, atmospheric deposition will be sampled, including both dry deposition accumulated prior to rainfall and wet deposition delivered through precipitation.

The analyses will include both dissolved and particulate-bound PFAS, including ultrashort-chain compounds and precursors using the Total Oxidizable Precursor (TOP) assay. To place the results in a broader context, metals and selected physicochemical parameters will also be analyzed, as these are well studied in stormwater and provide a useful basis for comparison.

The project is funded by the Swedish Environmental Protection Agency.