Microplastic ingestion by pelagic and benthic fish and diet composition: A case study in the NW Iberian shelf

We evaluated the incidence of microplastics in the digestive tract contents of four fish species: Engraulis encrasicolus, 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.Postprint2,35

Determinacion manual de urea en agua de mar

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Microplastic ingestion by pelagic and benthic fish and diet composition: A case study in the NW Iberian shelf

We evaluated the incidence of microplastics in the digestive tract contents of four fish species: Engraulis encrasicolus, 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

The seasonal cycle of micro and meso-plastics in surface waters in a coastal environment (Ría de Vigo, NW Spain)

Marine litter is an emerging environmental problem. In this study, micro and mesoplastics were determined for the first time in seawater in Ría de Vigo (Spain) identifying their concentration, annual cycle, size, shape and polymer composition. Besides, temporal variations at an annual scale were also established. The Ría de Vigo is well known for the important industry related to marine activities (fishing, mollusc culture, shipyards, and tourism). Three sampling stations were selected along the transverse axis of Ría and were monthly sampled for one year. Seawater samples were collected using a manta trawl and analyzed with ATR-FTIR, and Raman spectroscopy to determine plastic polymer type. The mesozooplankton community (0.2-20 mm) was also studied. The samples were collected with bongo nets in the same sampling stations as plastics. Manta trawl net (330 μm) was used to collect 32 samples (identifying 854 plastic particles; 677 microplastics and 177 mesoplastics). The mean concentration across all sites was 25.4 ± 13.4 items·km-2. The microplastics abundance was greater than that of mesoplastics (79%, and 21%, respectively). Around 30% of plastics analyzed were Polyethylene (PE), 19% were acrylates, 18% were Polypropylene (PP) and 10% were Polystyrene (PS). The main shapes of both micro and mesoplastics were fibers followed by paint sheets being black the main colour in both cases. The results showed high seasonal variability by micro and mesoplastics but similar spatial distribution. This seasonal heterogeneity can have effects on a futuremonitoring program. Furthermore, itwas demonstrated that pollution by mesoplastics cannot be estimated through the microplastics abundances. Regarding the values of microplastics-zooplankton, they present a great negative correlation.Postprint3,25

First data of the PAHs along a sediment core from Ria de Vigo

Sediment cores can inform about the temporal trend of pollutants in an environment. Different sediment layers, settled at different times represent the pollution in that moment. A sediment core in the inner part of the Ría de Vigo was collected and some layers analysed in order to determine the temporal trend of PAHs in the last decades. PAHs can have a natural (biogenic) and anthropogenic origin but generally the last one is the predominant. The main sources of PAHs to the environment are petroleum and coal combustions as well as fires or even the use of pitch or other petroleum products. In this study 35 individual PAHs were analysed (including parent and alkylated ones) as well as some groups of alkylated PAHs. A QA/QC is put in place to guarantee the quality of the analysis- The sum of 16 EPA PAHs was in the range of 200-1000 µg/kg d.w. with a clear increase in the values in the more recent layers pointing at the anthropogenic activity as one of the main drivers of the PAH concentrations in sediments. The values are in the range of other estuarine areas with values above the reference values (background) but generally below the ERL and so not expected to be causing adverse biological effects. The study of the isomeric ratios of PAHs show that the origin has not changed during the period studied and it is mainly petroleum combustion mixed with different types of combustion

Synthetic microfibers in the marine environment: A review on their occurrence in seawater and sediments

The objective of this review is to, summarize information on microfibers in seawater and sediments from available scientific information. Microfibers were found in all reviewed documents. An heterogeneous approach is observed, with regard to sampling methodologies and units. Microfibers in sediments range from 1.4 to 40 items per 50 mL or 13.15 to 39.48 items per 250 g dry weight. In the case of water, microfibers values ranges from 0 to 450 items.m(-3) or from 503 to 459,681 items.km(-2). Blue is the most common color in seawater and sediments, followed by transparent and black in the case of seawater, and black and colorful in sediments. Related with polymer type, polypropylene is the most common in water and sediments, followed by polyethylene in water and polyester in water and sediments. Some polymers were described only in water samples: high-density polyethylene, low-density polyethylene and cellophane, whilst only rayon was reported in sediments