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Concentrations of floating plastic were measured throughout the Mediterranean Sea to assess whether this basin can be regarded as a great accumulation region of plastic debris. We found that the average density of plastic (1 item per 4 m2), as well as its frequency of occurrence (100% of the sites sampled), are comparable to the accumulation zones described for the five subtropical ocean gyres. Plastic debris in the Mediterranean surface waters was dominated by millimeter-sized fragments, but showed a higher proportion of large plastic objects than that present in oceanic gyres, reflecting the closer connection with pollution sources. The accumulation of floating plastic in the Mediterranean Sea (between 1,000 and 3,000 tons) is likely related to the high human pressure together with the hydrodynamics of this semi-enclosed basin, with outflow mainly occurring through a deep water layer. Given the biological richness and concentration of economic activities in the Mediterranean Sea, the affects of plastic pollution on marine and human life are expected to be particularly frequent in this plastic accumulation region.
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... The high spatiotemporal variability of the currents in this basin causes that there are no known plastic retention areas. 20 In order to get a better picture of the flow field, the time-mean surface currents over 2006−2016 have been plotted as vectors in Figure 1. In the same figure, locations of the measurements used here are plotted for which references are shown in the legend. ...
... Correcting this missing variance leads to an estimate of 190−340 tonnes of floating plastics. This is somewhat lower than the estimate by Coźar et al., 20 where it was estimated to be 756−2969 tonnes. ...
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Estimates of plastic inputs into the ocean are orders of magnitude larger than what is found in the surface waters. This can be due to discrepancies in the sources of plastic released into the ocean, but can also be explained due to the fact that it is not well known what the most dominant sinks of marine plastics are, and on what time scales these operate. To get a better understanding on possible sources and sinks, an inverse modelling methodology is presented here for a Lagrangian ocean model, estimating floating plastic quantities in the Mediterranean Sea. Field measurements of plastic concentrations in the Mediterranean are used to inform parametrizations defining various sources of marine plastics, and removal of plastic particles due to beaching and sinking. The parameters of the model are found using inverse modelling, by comparison of model results and measurements of floating plastic concentrations. Time scales for the sinks are found, and likely sources of plastics can be ranked in importance. A new mass balance is made for floating plastics in the Mediterranean: for 2015 there is an estimated input of 2,100-3,400 tonnes, and of plastics released since 2006, about 170-420 tonnes remain afloat in the surface waters, 49-63% ended up on coastlines, and 37-51% have sunk down.
... As a result, there is widely increasing attention on the problems caused by the generation of plastic waste, with society trying to replace unsustainable habits. Plastic waste also severely causes marine pollution and has become a large-scale problem after only half a century of widespread plastic use [3]. The Ellen MacArthur Foundation (EMF) stated that most of the plastic packaging produced ends up in landfills or oceans: "With 8 million tons of plastic that reach the ocean every year, we urgently need to rethink the way we manufacture, use and reuse plastics." ...
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Every day, society's concern over pollution caused by plastic waste grows greater. One of the most intensive sectors for the use of plastic is the food industry. Companies in this sector face the challenge of transitioning to a more sustainable and less intensive model of plastic use, respecting the principles established for a circular economy. Accordingly, one of the questions that industries tend to ask is whether sustainability will influence the consumer's purchase decision. To respond to this, the factors that determine a consumer's sustainable purchase decision in relation to the plastic and food industry have been analyzed in this paper. For this, a regression analysis was performed on a sample of Dutch consumers. The results show that the decision of purchase of the consumer of the Food Industry is conditioned by factors such as age, sustainable behavior, knowledge of the Circular economy and the perception of usefulness of plastic.
... Also, fouling processes allow lowdensity plastics were available for benthic species (see, e.g. Andrady, 2011;Zettler et al., 2013;Cózar et al., 2015) Differences found in the ingestion of microplastics could be attributed to some specificities of the region under study. According to Gago et al. (2015), our study area is characterized by a medium-level of microplastic contamination in the neustonic layer of the water column. ...
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We evaluated the incidence of microplastics in the digestive tract contents of four fish species: Engraulis en-crasicolus, Sardina pilchardus, Callionymus lyra and Mullus surmuletus. Alkaline digestion (10% KOH) was used to degrade the organic matter. The percentage of fish with microplastics was 78% (88% fibres, 12% fragments). The main types of polymers identified by Raman spectroscopy were polyethylene and polypropylene. The diet of the four species was also studied and two feeding types were determined: plankton-feeders and benthic-feeders. The effect of a set of biological variables (Length, Fullness index, Fulton's condition factor and Feeding type) on the number and size of microplastics ingested was studied using Generalised Additive Models (GAMs). A significant increase in the number of microplastics with increasing length was observed. No significant effect of trophic variables (fullness index and feeding type) on the number and size of microplastics was found.
... Although many studies on seawater MPs contamination were carried out along the northern Mediterranean coasts (e.g. Eriksen et al., 2014;Suaria et al., 2016;Kedzierski et al., 2019aKedzierski et al., , 2019b, similar studies remain very scarce in southern Mediterranean Sea (Cózar et al., 2015;Cincinelli et al., 2019). ...
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... Those small plastic fragments were found to be approximately 1.5 cm in diameter. Currently, it is estimated that the average plastic concentration in Mediterranean surface waters is 243,853 items per km 2 (Cózar et al., 2015) with sizes between 0.2 and 500 mm, being the highest concentration of particles located between 0.5 and 2.5 mm. Some factors that contribute to the issue of marine litter are the intense coastal and maritime tourism, the great flow of navigation, the industrial and fishing activities and also the configuration of the Mediterranean sea as a closed basin with a particular system of currents (Cincinelli et al., 2019). ...
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