Impacts of sea spray aerosol transport of perfluoroalkyl acids (PFAAs) on coastal regions

Evidence has emerged that levels of perfluoroalkyl acids (PFAAs) are elevated in coastal regions despite there being no obvious sources.

In previous research, we have demonstrated that PFAAs emitted on sea spray aerosols (SSA) is an important source of PFAAs to air. It remains uncertain, however, what the contribution of SSA transport is to atmospheric deposition of PFAAs to land.

While modelling of transport and deposition undertaken in our research group indicates the importance of SAA transport and deposition of PFAAs in coastal regions, there is currently little empirical evidence for these impacts.

In this project, we aim to demonstrate that coastal zones in Denmark and Sweden are impacted by PFAAs through short-range transport and deposition of relatively large SSA particles with short atmospheric lifetimes.

We plan to:measure PFAAs in air on the Danish and Swedish coasts using high-volume air samplers and correlate PFAA air concentrations to SSA tracer ions measured in the same samples,measure PFAAs in different aerosol size fractions near the coast using a cascade impactor,measure wet and dry deposition of PFAAs using an automatic wet/dry deposition sampler, as well as levels of PFAAs in surface environmental media along a gradient from the sea inland,model SSA emission in the surf zone and SSA transport and deposition to land to explain our empirical data, anddisseminate the results to relevant stakeholders.