Microplastic analysis in sediments of the Elbe River by electrostatic separation and differential scanning calorimetry

Lucas Kurzweg; Maurice Hauffe; Sven Schirrmeister; Yasmin Adomat; Martin Socher; Thomas Grischek; Andreas Fery; Kathrin Harre

doi:10.1016/j.scitotenv.2024.172514

Microplastic analysis in sediments of the Elbe River by electrostatic separation and differential scanning calorimetry

Sci Total Environ. 2024 Apr 17:930:172514. doi: 10.1016/j.scitotenv.2024.172514. Online ahead of print.

Authors

Lucas Kurzweg¹, Maurice Hauffe², Sven Schirrmeister¹, Yasmin Adomat³, Martin Socher², Thomas Grischek³, Andreas Fery⁴, Kathrin Harre⁵

Affiliations

¹ Faculty of Agriculture, Environment and Chemistry, University of Applied Sciences Dresden, Friedrich-List-Platz 1, 01069 Dresden, Germany; Technical University Dresden, Faculty of Chemistry and Food Chemistry, Department for Physical Chemistry of Polymeric Materials, Mommsenstraße 6, 01069 Dresden, Germany.
² Faculty of Agriculture, Environment and Chemistry, University of Applied Sciences Dresden, Friedrich-List-Platz 1, 01069 Dresden, Germany.
³ Faculty of Civil Engineering, University of Applied Sciences Dresden, Friedrich-List-Platz 1, 01069 Dresden, Germany.
⁴ Technical University Dresden, Faculty of Chemistry and Food Chemistry, Department for Physical Chemistry of Polymeric Materials, Mommsenstraße 6, 01069 Dresden, Germany; Leibniz Institut für Polymerforschung Dresden e.V., Institute for Physical Chemistry and Polymer Physics, Hohe Str. 6, 01069 Dresden, Germany.
⁵ Faculty of Agriculture, Environment and Chemistry, University of Applied Sciences Dresden, Friedrich-List-Platz 1, 01069 Dresden, Germany. Electronic address: kathrin.harre@htw-dresden.de.

PMID: 38641120
DOI: 10.1016/j.scitotenv.2024.172514

Abstract

This study presents the most extensive investigation of microplastic (MP) contents in sediment from the Elbe River. We employed electrostatic separation (ES) and differential scanning calorimetry (DSC) to overcome limitations of sample throughput and time-consuming analysis. In total 43 sediment samples were collected using a Van-Veen grab. Subsequently, coarse materials (d₁₀ > 100 μm) and fine materials (d₁₀ ≤ 100 μm) were enriched using ES and density separation. DSC was utilized for MP identification and quantification, based on the phase-transition signals of eight different polymers. MP presence was detected in 25 samples, with successful quantification in 12 samples. The MP content in coarse material samples from shoreline areas ranged from 0.52 to 1.30 mg/kg, while in fine material samples from harbor basins, it ranged from 5.0 to 44.6 mg/kg. The most prevalent polymers identified were LD-PE, HD-PE, PP, and PCL. These findings confirmed the suitability of DSC for analyzing MP in complex environmental samples. MP hotspots were identified in harbor basins, where natural sedimentation processes and increased anthropogenic activities contribute to MP accumulation. Additionally, industrial sewage potentially contributed to MP content in sediment samples. The highest pollution levels were observed in the middle Elbe, between the confluences of Mulde and Havel. Lowest MP contents were found in the lower Elbe, potentially influenced by tides. Future studies should focus on holistic investigations of selected river sections, encompassing sediment, water, and biota samples, rather than the entire catchment area. This approach would facilitate the generation of spatiotemporal data on MP distribution in freshwater streams. In addition, more research is needed to explore potential interactions between different MP and sediment types during DSC measurements.

Keywords: Differential scanning calorimetry; Elbe River; Electrostatic separation; Microplastic; Monitoring; Sediments.