Identification and Quantification of Microplastics in Arctic Sea Ice North of Svalbard

The accumulation of macro- and microscopic sized plastic litter in aquatic systems has been reported since the early 1970ꞌs, approximately 30 years after the beginning of plastic mass production. Since then, microscopic sized plastic particles are found in various aquatic habitats in densely populated areas as well as in remote places like the Arctic. Until now, two publications document the presence of microplastic in Arctic sea ice with highly divergent results due to different methods of preparation and analysis. This study aims to gain further information about microplastic in Arctic sea ice by applying the preparation procedure and analysis method used in one of the previous studies to obtain comparable data. Therefore, first year and multiyear ice samples taken north of Svalbard were examined in regard to concentration, distribution and accumulation of plastic particles and polymer types. The identification and quantification was performed using focal plane array (FPA) - based micro-Fourier transform infrared (μ-FTIR) spectroscopy. In total, three ice core samples, consisting of two parts each, from three different stations north of Svalbard were analyzed. The highest concentration found in this study was 6.85 ± 6.72 x 105 N/m3, however, it was one order of magnitude smaller than those documented in the reference study. In total, eleven different polymer types were identified in this study as well. The most frequently found polymers types in first year ice were polyethylene (PE) and polyamide (PA), whereas varnish particles were dominant in multiyear ice. In contrast to the reference study, a clear accumulation pattern within the examined ice cores was not observed. The applied methods gained comparable data but further improvements should be implemented in future studies in regard to sample purification, and used filter material for the measurement to obtain more accurate data.