Occurrence of Microplastics in Danube River

Analyzing Microplastics in the Environment: Striving to Better Assess Occurrence, Fate and Effects
Poster Presentation

Prepared by A. Kerndorff
German Environment Agency, Corrensplatz 1, Berlin, Berlin, 14195, Germany


Contact Information: alexander.kerndorff@uba.de; 00493089031304


ABSTRACT

Plastics, and microplastics in particular, are still part of scientific and regulatory discussions. Their inputs from land ultimately end up in the oceans, where they remain for a long time. Macro plastic degrades into micro- and nano plastic particles and thus, plastic particles are reported in almost every ecosystem component, even in deep-sea sediments (van Cauwenberghe et al. 2013, Woodall et al. 2014, Yao et al. 2019) and remote marine gyres (Law et al. 2010, Maximenko et al. 2012, Pan et al. 2019). Especially river systems represent an important path of entry into the oceans. The Danube as the second largest river in Europe can therefore be an example for the occurrence of plastics in other large river systems. Within the scope of the Joint Danube Survey 4 (JDS-4), a comprehensive screening of micro plastics was carried out over the entire river course. Sampling was done by sedimentation boxes positioned 0.5 m below the water surface. The exposure time was 14 days; followed by thermal extraction desorption gas chromatography mass spectrometry (TED-GC/MS) for determination of the total mass contents of various plastic polymers in the suspended particulate matter samples (SPM). The samples were separated into different fractions by means of cascade filtration. In an initial exploratory analysis, the fractions > 100 µm and < 100 µm were examined for their polymer contents. The results of the TED-GC/MS analysis detected micro plastic at different levels in each sample. The analyzed contents ranged between 0.00 - 22.24, 0.00 - 0.45, 0.00 - 1.03 and 0.00 - 3.32 for polyethylene, polypropylene, the tyre compound styrene butadiene rubber and polystyrene [µg/mg] SPM, respectively. There was no clear trend along the Danube river with increasing or decreasing contents. However, the data indicates a relatively constant, mainly PE-based background load with some local micro plastic hotspots.