Microplastic pollution in surface water and sediments in the urban section of the Vistula River (Poland)

Ilona Sekudewicz; Agnieszka Monika Dąbrowska; Marcin Daniel Syczewski

doi:10.1016/j.scitotenv.2020.143111

Microplastic pollution in surface water and sediments in the urban section of the Vistula River (Poland)

Sci Total Environ. 2021 Mar 25:762:143111. doi: 10.1016/j.scitotenv.2020.143111. Epub 2020 Oct 20.

Authors

Ilona Sekudewicz¹, Agnieszka Monika Dąbrowska², Marcin Daniel Syczewski³

Affiliations

¹ Institute of Geological Sciences, Polish Academy of Sciences, Twarda 51/55, PL-00818 Warsaw, Poland. Electronic address: i.sekudewicz@twarda.pan.pl.
² University of Warsaw, Faculty of Chemistry, Laboratory of Spectroscopy and Intermolecular Interactions, Pasteura 1, PL-02093 Warsaw, Poland; University of Warsaw Biological and Chemical Research Centre, Żwirki i Wigury 101 st., PL-02089 Warsaw, Poland.
³ Faculty of Geology, University of Warsaw, Żwirki i Wigury 93, PL-02089 Warsaw, Poland.

PMID: 33131873
DOI: 10.1016/j.scitotenv.2020.143111

Abstract

The main hypothesis of this study was that the microplastic (MP) concentration would be higher in the city centre. The MP (<5 mm) abundance and distribution in the urbanized section of the Vistula River were examined. Samples were collected from three different sites: 1) the less urbanized part of the city, 2) the area close to the tributary outlet and wastewater treatment plant (WWTP), and 3) the city centre. The abundance of MPs in water ranged from 1.6 to 2.55 items L^-1, whereas in the sediments, it varied from 190 to 580 items kg^-1. The highest MP concentration was observed in the water collected in the city centre. However, in the case of sediments, the most polluted sample was collected from a sampling point located near the WWTP and tributary outlet. The diversity of the MPs abundance along the river was associated with the hydrological and sedimentological conditions, which was confirmed by the grain size analysis of sediments. The dominant type of MPs in both the water and sediment samples was fibre. The MPs were characterized by Raman spectroscopy as polystyrene (PS), polypropylene (PP), and a variety of other materials with different levels of deterioration. The images obtained by scanning electron microscopy (SEM) showed different disintegration features. Moreover, the SEM analyses revealed the occurrence of adhered particles and diatoms on the surface of MPs. The adsorption of various elements onto the MPs surface and the adhered particles was confirmed by energy-dispersive X-ray spectroscopy. The conducted studies emphasized the significance of the impact of large urban agglomerations, such as the Warsaw metropolitan area, on the concentration of MPs in rivers. Further studies are needed to better assess, for instance, the precise mode through which MPs in urban regions are transported by rivers to the seas.

Keywords: Microplastic; Primary microplastics; Raman spectroscopy; Sediments contamination; Urban area; Vistula pollution.