Organic pollutants, nano- and microparticles in street sweeping road dust and washwater
Journal article, 2020

Road areas are pollution hotspots where many metals, organic pollutants (OPs) and nano/microparticles accumulate before being transported to receiving waters. Particles on roads originate from e.g. road, tyre and vehicle wear, winter road maintenance, soil erosion, and deposition. Street sweeping has the potential to be an effective and affordable practice to reduce the occurrence of road dust, and thereby the subsequent spreading of pollutants, but there is currently little knowledge regarding its effectiveness. In this paper we investigate the potential of street sweeping to reduce the amounts of OPs and nano/microparticles reaching stormwater, in a case study sampling road dust and washwater from a street sweeping machine, road dust before and after sweeping, and stormwater. The compound groups generally found in the highest concentrations in all matrices were aliphatics C5–C35 > phthalates > aromatics C8–C35 > PAH-16. The concentrations of aliphatics C16–C35 and PAHs in washwater were extremely high at ≤ 53,000 µg/L and ≤ 120 µg/L, respectively, and the highest concentrations were found after a 3-month winter break in sweeping. In general, fewer aliphatic and aromatic petroleum hydrocarbons and PAHs were detected in road dust samples than in washwater. The relative composition of the specific PAH-16 suggests tyre wear, vehicle exhausts, brake linings, motor oils and road surface wear as possible sources. The study indicates that many of the hydrophobic compounds quantified in washwater are attached to small particles or truly dissolved. The washwater contains a wide range of small particles, including nanoparticles in sizes from just below 1 nm up to 300 nm, with nanoparticles in the size range 25–300 nm present in the highest concentrations. The results also indicated agglomeration of nanoparticles in the washwater. The street sweeping collected a large amount of fine particles and associated pollutants, leading to the conclusion that washwater from street sweeping needs to be treated before disposal.

Wet dust sampler

Road runoff

PAHs

Stormwater

Particle size distribution

Aliphatics

Author

Maria Polukarova

The Swedish National Road and Transport Research Institute (VTI)

Anna Markiewicz

Chalmers, Architecture and Civil Engineering, Water Environment Technology

Karin Björklund

Chalmers, Architecture and Civil Engineering, Water Environment Technology

Ann-Margret Hvitt Strömvall

Chalmers, Architecture and Civil Engineering, Water Environment Technology

Helen Galfi

City of Gothenburg

Yvonne Andersson-Sköld

The Swedish National Road and Transport Research Institute (VTI)

Mats Gustafsson

The Swedish National Road and Transport Research Institute (VTI)

Ida Järlskog

The Swedish National Road and Transport Research Institute (VTI)

Maria Aronsson

Trafikkontoret

Environment International

0160-4120 (ISSN)

Vol. 135 105337

Subject Categories

Environmental Sciences

Environmental Health and Occupational Health

Public Health, Global Health, Social Medicine and Epidemiology

DOI

10.1016/j.envint.2019.105337

More information

Latest update

2/20/2020