Occurrence of tire and bitumen wear microplastics on urban streets and in sweepsand and washwater
Journal article, 2020

Tire and road wear particles have been identified as a potential major source of microplastics in the environment. However, more knowledge of the emissions and their further fate in the environment is needed, and the effectiveness and benefits of potential measures must be investigated to support future risk management efforts. Here the concentrations of tire and bitumen microplastic particles (TBMP) on roads and in nearby in stormwater, sweepsand and washwater were measured for the first time within the same area and time period. The analysis also included plastic, paint and fiber particles. Road dust was sampled on the road surface using a wet dust sampler, before and after street sweeping on two occasions. On each of these occasions, and several occasions during a four-month period with frequent street sweeping, sweepsand and washwater, as well as flow-weighted sampling of stormwater, were collected. TBMP concentrations were operationally defined, using density separation for some samples, followed by analysis by stereo microscopy. Sodium iodide (NaI) was found to be effective for density separation of TBMP. The largest proportion of anthropogenic microplastics detected consisted of tire tread wear and bitumen. The number of TBMP ≥100 μm in the WDS samples was up to 2561 particles/L. Sweepsand and washwater contained high amounts of TBMP ≥100 μm, up to 2170 particles/kg dw and 4500 particles/L, respectively. The results show that the sweeper collects considerable amounts of TBMP, and thus weekly sweeping might prevent further transport of TBMP to the receiving stormwater. In stormwater the number of particles ≥100 μm was up to 3 particles/L and ≥ 20 μm was up to 5900 particles/L showing the importance of analysing smaller microparticle sizes than 100 μm in all samples in future studies. This study also confirms that there is a substantial volume of TBMP generated from traffic that enters the environment.

Road dust



Tire wear

Street sweeping



Ida Järlskog

Chalmers, Architecture and Civil Engineering, GeoEngineering

The Swedish National Road and Transport Research Institute (VTI)

Ann-Margret Hvitt Strömvall

Chalmers, Architecture and Civil Engineering, Water Environment Technology

Kerstin Magnusson

IVL Swedish Environmental Research Institute

Mats Gustafsson

The Swedish National Road and Transport Research Institute (VTI)

Maria Polukarova

The Swedish National Road and Transport Research Institute (VTI)

Helen Galfi

City of Gothenburg

Maria Aronsson

City of Gothenburg

Yvonne Andersson-Sköld

The Swedish National Road and Transport Research Institute (VTI)

Chalmers, Architecture and Civil Engineering

Science of the Total Environment

00489697 (ISSN) 18791026 (eISSN)

Vol. 729 138950

Innovative and Sustainable Solutions to Reduce Pollution of Roads and Road

VINNOVA (2018-00652), 2018-04-18 -- 2020-04-17.

Load and measures to reduce the load of traffic related persistent organic pollutants (POP) and micro/nanoplastics

The Swedish National Road and Transport Research Institute (VTI), 2019-01-01 -- 2021-12-31.

Formas (2017-00720), 2019-01-01 -- 2021-12-31.

Driving Forces

Sustainable development

Subject Categories



Environmental Sciences



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