Contribution of Research Station Activities to Microplastic Pollution in Antarctica: A Case Study of King Sejong Station

Microplastics (MPs) are widespread across the globe, including remote regions such as Antarctica. Until recently, Antarctic MPs have been primarily considered to originate from external sources via ocean currents. However, the intensification of human activities within the Antarctic Circumpolar Current (ACC) has raised concerns that local sources, including research stations, could become significant contributors to MP pollution. Nevertheless, the impacts of local sources remain unclear due to the lack of observation data and snap-shot study results. Frequent temporal monitoring linking potential pollution sources with surrounding environments can help assess and understand the impacts of research stations. This study aimed to quantify and characterize MP pollution from research station activities. To this end, we conducted seasonal or monthly sampling of multiple compartments at or near the King Sejong Station (KSS; located on Barton Peninsula, King George Island)—aquatic (wastewater, seawater, beach sediment, marine sediment), atmospheric (outdoor and indoor air), and terrestrial (soil and snow)—over three years (2023-2025). Here, we present preliminary results, mainly focusing on aquatic compartments. In 2023, influent and effluent discharged from KSS-wastewater treatment plant (WTP) and surface seawater near the KSS-pier in Marian Cove were collected in January, April, July, and October. Additionally, five beach sediments and three marine sediments were collected along a transect from the outer to the inner part of Marian Cove. There was no correlation between the number of residents and MP abundance in wastewater; However, an increasing trend in MP abundance was observed with daily wastewater discharge. Contrary to typical observations, MPs in the effluent (573,100 ± 394,615 n/m3) were more than twice as high as in the influent. This is presumed to result from sludge re-suspension that concentrated MPs, indicating inadequate treatment efficiency in KSS-WTP. We estimate that 5 billion MP pieces may enter Marian Cove annually from KSS-WTP. Surface seawater contained two or three orders of magnitude lower MPs (1,099 ± 1,269 n/m3) compared to WTP effluents but higher levels than those in some mid-latitude coastal regions or other open oceans. MP abundances in beach (205 ± 190 n/m3) and marine sediments (277 ± 107 n/m3) were highest at the site closest to the WTP outlet, with a significant correlation with distance. The detected polymer types were 22 in wastewater, 16 in seawater, and 10 in sediments. Although PP was the predominant polymer, its percentages were 22.9%, 55.8%, 49%, and 31.7%, respectively. These findings indicate that MPs from KSS-WTP are fractionated across media, with less dense polymers remaining longer in seawater and beach sediments. This study provides baseline data on the impact of research station activities, emphasizing the need for improved environmental protocols and systematic monitoring to mitigate MP pollution in Antarctica.Acknowledgement: This study was supported by Korea Polar Research Institute (KOPRI, PE24170), and was also partially supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (No. RS-2024-00356940).