A new study led by researchers at Shanghai Jiao Tong University has revealed the key physical and biogeochemical processes driving the distribution of per- and polyfluoroalkyl substances (PFAS) in the Antarctic marine environment. Focusing on the Amundsen Sea Polynya, the research provides critical insights into how factors such as sea ice dynamics, ocean circulation, and biological activity influence the transport and fate of these persistent contaminants in polar regions.

The study, published in the Nature Index journal Environmental Science & Technology, was conducted by PhD student Chenglin Liu from the School of Oceanography at Shanghai Jiao Tong University as the first author (Figure 1). The study was conducted under the supervision of Prof. Yuxin Ma at the School of Oceanography, served as the corresponding author. Co-authors include Professor Yitao Pan from the School of Environmental Science and Engineering, Researcher Ruifeng Zhang and Associate Professor Yuanyuan Feng from the School of Oceanography at Shanghai Jiao Tong University, as well as Researcher Jianfeng He and Senior Engineer Shunan Cao from the Polar Research Institute of China. The School of Oceanography at Shanghai Jiao Tong University is the primary affiliation unit of this work.

PFAS are a class of man-made chemicals widely used in industrial production and daily life. Due to their environmental persistence, bioaccumulation potential, and capacity for long-range transport, they have become one of the most concerning categories of emerging pollutants globally. Although PFAS have been widely detected in polar oceans, the physical and biogeochemical drivers governing their distribution remain unclear. This study focused on the Amundsen Sea Polynya in the Southern Ocean, analyzing the distribution of PFAS throughout the full-depth water column. By integrating physical processes (sea ice brine rejection, Circumpolar Deep Water intrusion) and biological processes (high productivity in polynyas), the research investigated the physical and biogeochemical factors driving PFAS dynamics.

The study found that short-chain PFAS (e.g., perfluorobutanoic acid, PFBA) exhibited nearshore enrichment, primarily driven by atmospheric aerosol transport and wet deposition, and were released through summer meltwater. Concurrently, continuous brine rejection during sea ice formation in the polynya facilitated the preferential removal of PFBA, leading to its accumulation in the winter water layer. In contrast, long-chain PFAS (especially 6:2 fluorotelomer sulfonic acid, 6:2 FTSA) were retained in sea ice during brine rejection and transported offshore by katabatic winds, subsequently being released in the ice edge zone during late summer ice melt (Figure 2). The full-depth enrichment of 6:2 FTSA in the ice edge zone was modulated by the biological pump (particle adsorption-settling), and 6:2 FTSA exhibited significant biomagnification in krill and penguins, escalating ecological risks. Additionally, PFBA was detected in Circumpolar Deep Water, suggesting potential cross-basin transport via the meridional overturning circulation, implying that global intermediate and deep oceans could act as long-term reservoirs for PFAS (Figure 3). 

Figure 2. The full water depth vertical distribution of typical PFAS in the sampling area.

Figure 3. The concentration levels of PFBA in different water masses.

This study reveals, for the first time, the spatiotemporal heterogeneity of PFAS in a typical Antarctic polynya region, deepens the understanding of PFAS transport mechanisms from the perspective of physical and biogeochemical regulation, and proposes the potential role of meridional overturning circulation as a conveyance pathway, offering critical insights into the global fate of PFAS.

This research was supported by the National Key Research and Development Program of China, the Southern Ocean Special Plan, the National Natural Science Foundation of China, and the Shanghai Science and Technology Commission.

Reference: Liu, C.; Pan, Y.; Zhang, R.; Feng, Y.; Cao, S.; He, J.; Ma, Y. Traditional and Emerging Per- and Polyfluoroalkyl Substances in the Amundsen Sea Polynya, Antarctica: Physical and Biogeochemical Drivers. Environ. Sci. Technol. 2026, 60 (4), 3592–3604. 

DOI: https://doi.org/10.1021/acs.est.5c15468