Abundance and composition of small floating plastics in the eastern and southern sectors of the Atlantic Ocean.

We report the distribution of floating plastics in the eastern and southern sectors of the Atlantic Ocean based on 35 neuston net trawl samples collected during two research cruises in 2016 and 2017. Plastic particles (>200 µm) were found in 69% of net tows, with median densities of 1583 items·km-2 and 5.1 g·km-2. Most particles (80% of 158) were microplastics (<5 mm) of secondary origin (88%), followed by industrial pellets (5%), thin plastic films (4%) and lines/filaments (3%). Due to the large mesh size we used, textile fibers were not considered in this study. µFTIR analysis revealed that most particles found in the net were made of polyethylene (63%), followed by polypropylene (32%) and polystyrene (1%). A transect between 0 and 18°E along 35°S in the South Atlantic Ocean revealed higher densities farther west, supporting the accumulation of floating plastics in the South Atlantic gyre, mainly west of 10°E.

The Mediterranean Plastic Soup: synthetic polymers in Mediterranean surface waters.

The Mediterranean Sea has been recently proposed as one of the most impacted regions of the world with regards to microplastics, however the polymeric composition of these floating particles is still largely unknown. Here we present the results of a large-scale survey of neustonic micro- and meso-plastics floating in Mediterranean waters, providing the first extensive characterization of their chemical identity as well as detailed information on their abundance and geographical distribution. All particles >700 µm collected in our samples were identified through FT-IR analysis (n = 4050 particles), shedding for the first time light on the polymeric diversity of this emerging pollutant. Sixteen different classes of synthetic materials were identified. Low-density polymers such as polyethylene and polypropylene were the most abundant compounds, followed by polyamides, plastic-based paints, polyvinyl chloride, polystyrene and polyvinyl alcohol. Less frequent polymers included polyethylene terephthalate, polyisoprene, poly(vinyl stearate), ethylene-vinyl acetate, polyepoxide, paraffin wax and polycaprolactone, a biodegradable polyester reported for the first time floating in off-shore waters. Geographical differences in sample composition were also observed, demonstrating sub-basin scale heterogeneity in plastics distribution and likely reflecting a complex interplay between pollution sources, sinks and residence times of different polymers at sea.