Riverine microplastics in the Hungarian Danube: distribution, sources, and characterisation

Keywords: Microplastics, FTIR spectroscopy, microplastic characterisation, riverine microplastics, plastic pollution

Abstract

Microplastics, defined as plastic particles smaller than 5 mm, have become a pressing global environmental issue. Ineffective recycling practices allow plastics to enter and persist in the environment, breaking down into smaller particles that travel through pathways like rivers. These microplastics can accumulate in ecosystems, where they pose significant risks to flora, fauna, and potentially human health. This study focuses on riverine microplastic pollution in the Hungarian section of the Danube River, Europe’s second-largest river, as well as in its tributary system. The Danube is a vital water source for Budapest and plays a crucial role in the region’s economy and ecological balance. Water samples were collected at varying river depths using a Multilevel Manta Net. Advanced laboratory techniques, including Fourier-transform infrared spectroscopy and digital microscopy, were used to identify and characterise microplastics collected. Additionally, flow measurements were conducted to estimate mass-flux rates. These findings contribute to developing practical measures for understanding, managing, and reducing microplastic pollution in freshwater systems. The findings revealed an average microplastic concentration of 0.311 mg/m³, corresponding to 142 particles/m³. The most frequently identified polymers were polystyrene, polyethylene, and polypropylene, which appeared predominantly as fragments, foam, and flakes. The microplastics exhibited a range of colours, including yellow, black, grey, and green.

Author Biographies

Pegah Jahanpeyma , Budapest University of Technology and Economics, Department of Hydraulic and Water Resources Engineering

PEGAH JAHANPEYMA received her bachelor’s degree in project management engineering from Paramour University in Tehran in 2012, and her master's degree in Hydraulic Structures from Azad University in South Tehran in 2015. She is currently a doctoral student and research assistant at the Department of Hydraulic Engineering and Water Management of the Budapest University of Technology and Economics. Her doctoral research topic is "Analysis of Microplastic Transport in Rivers". Her research interests include the study of plastic pollution in rivers, flow conditions, and sediment migration using various field methods.

Sándor Baranya , Budapest University of Technology and Economics, Department of Hydraulic and Water Resources Engineering

SÁNDOR BARANYA received his Civil Engineering degree from the Budapest University of Technology and Economics (BME) in 2003 and his PhD from the same university in 2010. He is currently the head of the Department of Hydraulic Engineering and Water Management at BME and an associate professor. His research interests include the study of riverbed morphology, flow dynamics, and sediment migration using field methods and computer modeling. He has been a member of the Hungarian Hydrological Society since 2003.

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Published
2026-07-22
How to Cite
JahanpeymaP., & BaranyaS. (2026). Riverine microplastics in the Hungarian Danube: distribution, sources, and characterisation. Hungarian Journal of Hydrology, 106(EN1), 4-16. https://doi.org/10.59258/hk.24053
Section
Scientific Papers