First evidence of airborne microplastics in the sub-Antarctic Beagle Channel: Detection and characterization by infrared and Raman microspectroscopies

Abstract

Microplastic pollution is increasingly recognized as a global environmental issue; however, atmosphericmicroplastic circulation remains poorly studied in sub-Antarctic regions, especially in southern South America. This study presents the first evidence of airborne microplastics in the sub-Antarctic Beagle Channel, based onpassive sampling conducted on Isla Redonda, an uninhabited island near Ushuaia, Argentina. Passive samplerswere employed over an 18-month period, allowing for continuous collection of atmospheric particles. Suspectedanthropogenic particles were analyzed using FTIR and Raman microspectroscopies to determine polymercomposition and associated additives. Fibers were the dominant particle type, accounting for over 80 % of thetotal. Semi-synthetic cotton, polyamide, polyester, and polyethylene were the most identified polymers. Ramananalysis further revealed the presence of industrial pigments, including indigo, on both synthetic and semi-synthetic fibers. The predominance of textile-related polymers and dyes suggests a strong influence of long-range atmospheric transport, likely from southern South America, as well as potential local contributions fromthe nearby city of Ushuaia. These findings, along with the use of passive samplers, establish a crucial baseline forfuture atmospheric microplastic monitoring in high-latitude regions and underscore the strategic importance ofincluding sub-Antarctic areas in global efforts to understand the dispersion pathways and environmental impactsof airborne microplastics.