Abundance and characterization of floating microplastics along the Tuscany coast (Italy): the first aplication of the MSFD monitoring proticol

Due to the increasing use of plastic and its dispersion in the marine environment andaccumulation in all habitats, the issue of plastic debris needs to be deeply investigated [1]. In particular, despite the Mediterranean sea is one of the hot spot area in the world for plastic debris accumulation [2], the knowledge on distribution and occurrence of floating microplastics is still lacking. Microplastics can affect marine biota increasing the likelihoodof ingestion of plastics by marine organisms entering the food web. For this reason the European Union has promoted the Marine Strategy Framework Directive (MSFD) with the aim of reaching the "Good Environmental Status" by 2020. This work has been carried out as part of implementation of the Descriptor 10.1.3 [3] of the MSFD in Tuscany (Italy), with the aim to gain information on abundance and distribution of microplastics. Sampling has been realized in two seasons (winter and spring) using a manta trawl (330 μm mesh size). Samples were collected along 4 transects 100 km far from each other, located from the estuary of Arno river to the promontory of Argentario. Each transect was divided into 4 stations located at increasing distance from the coast (20 km, 10 km, 5 km, 0.5 km). The analysis were performed according to the MSFD protocol. All data was normalized to the total volume of water filtered and expressed as items/m3 and microplastics were characterized by colour, shape and size. A total of 2670 microplastics were isolated in the 72 samples, white was the predominant color; the majority of items are fragments and the most of microplastics fall in the measured from 1 to 2.5mm size class. In the winter, the highest values of microplastics have been found in the station at 20 km from the coast with a gradient decreasing in the stations closer to coast; whereas in spring, the highest was found in the station at 10 km. This work represents the first application of the MSFD protocol in the monitoring of microplastics in Tuscany and will allow to understand the distribution and abundance of microplastics in the Tuscany coastal waters.