Dispersion assessment of microplastics in marine sediments from McKellar and Martel Inlets, King George Island, Antarctica

Pollution in pristine ecosystems is a high concern according that this research evaluates the occurrence of microplastics (MPs) in marine sediments from Mackellar and Martel Inlets in Admiralty Bay, King George Island, Antarctica. The samples were collected during January 2023. Colors and shape of MPs were determined by sampling points and compared with depth and distance to coast. MPs abundance ranged from 0 to 0.38 particles per-gram (mean 0.21, stand.dev. 0.13). Fibers were the dominant (92%), followed by fragments (8%). Concerning colors, blue (51.9%) and black (36.6%) were common. Particle sizes were within the 0.01-1 mm range, accounting for 73% of the total. Particles were analyzed by Raman spectroscopy, and two types of polymers were identified polyethylene terephthalate or PET (24%) and PET glycol (6%) the remained particles were undetermined due to their small size. The dispersion of blue and black particles with depth was high (r = 0.8) mainly in the deepest stations. While the dispersion of particles to the distance to coast was low representative, however seems to be some relevance to fibers more than for fragments. Our findings confirm the presence of synthetic particles in Antarctica a remote and fragile environment with unique ecological structure and dynamic, reinforcing the need for continued monitoring efforts and preventive measures to mitigate microplastic pollution. Sediment accumulation of MPs affects to the benthic communities but also to the entire marine food web as well as would alter its physical conditions. The isolated condition of Antarctica would increase the effect of anthropogenic pollutants.