Transport and dispersion of PFOA and PFOS in the Black Sea

• Published in: Environmental research 2024-07, Vol.252 (Pt 1), p.118100-118100, Article 118100
• Main Authors: Miladinova, S., Garcia-Gorriz, E., Macias-Moy, D., Stips, A.
• Format: Article
• Language: English
• Subjects: Black Sea; cooling; Future scenario; perfluorooctane sulfonic acid; perfluorooctanoic acid; PFOA; PFOS; surface water; Tracer model; winter
• ISSN: 0013-9351; 1096-0953
• DOI: 10.1016/j.envres.2024.118100

A 3-D transport and dispersion model was applied to study the recent past and future dynamics of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) concentrations in the Black Sea for the 2016–2030 period. The modelled surface concentrations show a distinct seasonal behaviour, shaped by winter to spring convective mixing. A significant increasing long-term trend in PFOS concentrations is established, with concentrations in water layers 200 m below the surface increasing at 4–8% per year. Driving mechanisms for PFOA and PFOS transport and accumulation in the subsurface and deeper layers are the cooling of the surface water in winter and the transport of water masses from the North Western Shelf (NWS) of the Black Sea. A simulated 50% phase-out of PFOA and PFOS from 2020 to 2030 shows a 21% reduction in PFOA, while PFOS continues to increase. •Recent past and future distributions of PFOA and PFOS in the Black Sea are simulated.•A key mechanism for removing dissolved substances is proposed.•Modelling suggests mean PFOS concentration in the Black Sea is above 0.18 μg m−3.•More than a 50% reduction in PFOS imports is needed to prevent its future increase.