PFAS concentrations in the blood of Danish surfers

Per- and poly-fluoroalkyl Substances (PFAS) have been used for decades in countless households and industrial products. Many PFAS do not degrade and are thus ubiquitous in the environment and within organisms. Humans are primarily exposed to PFAS through ingestion and inhalation, and such exposure has been associated with several health effects. Some PFAS accumulate in the top layer of seawater and in seafoam up to 100,000 times the concentration in bulk seawater. No studies have investigated whether exposure to seafoam or aerosols by surfing or other water activities is associated with a higher PFAS burden. This study aimed to measure PFAS concentrations in the blood of 34 Danish surfers and investigate the effect of annual surfing hours on these concentrations.

A cross-sectional questionnaire-based study of surfers from the West Coast of Denmark was conducted to investigate a possible association between annual surfing hours and serum PFAS concentrations including PFOA, PFOS, PFNA, PFDA and PFHxS.

All 34 surfers had measurable PFAS concentrations in their blood. However, annual surfing hours were not associated with increased PFAS concentrations. Unadjusted subgroup analyses showed statistically significant associations with male sex and consumption of meat from free-ranging animals with higher PFAS concentrations in blood, although these associations might be driven by other factors.

This study descriptively explored the distribution of PFAS concentrations in different subgroups based on potential risk factors of higher PFAS exposure. Even though no association between surfing and PFAS concentrations in blood was found, several other factors are suspected to be associated with increased concentrations. To prevent exposures that might lead to adverse health effects, further studies are needed.