Synthetic microfibers in marine sediments and surface seawater from the Argentinean continental shelf and a Marine Protected Area

In this work, samples were collected from the Argentinean continental shelf -including a Marine Protected Area (MPA) - to assess the occurrence and distribution of synthetic microfibers (MFs), a widespread type of microplastic. MFs were present at 100% of the samples showing an average concentration of 182.85 +/- 115.14 particles per Kg of dry sediment and 0.14 +/- 0.08 items per m(3) of marine water. MFs less than 1 mm were the most abundant (56.4% and 63%, for sediment and surface seawater respectively), followed by 1-2 mm and then 2-3 mm. In regards to the colour, both sediments and water had the major percentage of black MFs (25.6% and 28%, respectively) and the lowest one of green MFs (2.5% and 3%, respectively). Finally, MFs content in sediments was inversely correlated with depth (r = -0.93, p < 0.05). These findings provide the first evidence of microplastic contamination at the Argentinean continental shelf.