The results, with an overview of the microplastic distribution in the North Sea, were published in February 2021 in Environmental Science & Technology. The research team, led by Dr. Scholz-Böttcher, filtered plastic particles with a diameter of less than one millimeter from water specimens taken in 2016 and 2017 from the vicinity of major shipping lanes in the German Bight, and analyzed their chemical composition. Unlike earlier studies, the research team not only determined the number of particles for the North Sea, but also determined for the first time the mass distribution in order to obtain a more comprehensive picture of the distribution of the various types of plastic. The figures from the University of Oldenburg showed surprisingly that the specimens contained mainly so-called acrylates and polycarbonates and far fewer packaging plastics and PVC. According to the research team, the biggest source of plastic in the environment is packaging waste from consumer products. Their main components are polyolefins and PET. These polymers were found above all near to the coast. Close to large shipping routes on the open North Sea or in the mouth of the river Elbe, on the other hand, they were predominantly plastic types that are used, for example, as binders in acrylic paints. The obvious conclusion is therefore that the particles found in the sea stem from marine paints. The plastics are used in the paints to prevent undesirable growth or fouling on the hulls, but are abraded by the wind and waves. "We assume that vessels leave behind a kind of "skid mark" in the water, which, as a source of microplastic, is of similar significance to that of tire abrasion from cars on land," says Scholz-Böttcher.
To the original publication: Christopher Dibke, Marten Fischer und Barbara M. Scholz-Böttcher: “Microplastic Mass Concentrations and Distribution in German Bight Waters by Pyrolysis-Gas Chromatography-Mass Spectrometry/Thermochemolysis Reveal Potential Impact of Marine Coatings: Do Ships Leave Skid Marks?”
- wissenschaft.de (26.2.2021)
- picture: © American Chemical Society