Toward more intercomparable road dust studies

Abstract

Road dust (RDS) often contains elevated concentrations of pollutants, especially metals. Numerous studies were performed in the last two decades investigating the concentrations of metals like Cu, Pb, and Zn in RDS. In a literature search 177 studies were found where RDS bulk samples were analyzed. In another 49 studies the RDS samples were split into a number of size fractions to consider also the size dependence of the metal concentrations. In RDS bulk sample studies, the upper size limit (USL) of the RDS samples ranged from 2 mm to more than 2000 mm. This is partly a result of the different aims of the studies. However, the concentrations of metals in RDS particles are quite size-dependent. Consequently, comparing of results from different studies makes little sense. Based on the available literature, a standardized sample preparation sequence is proposed in this work. To serve the various aims of RDS studies the separation of the samples into four size fractions is suggested: <10 mm, 10-63 mm, 63-250 mm, and 250-2000 mm. The determination of the mass fractions of the size fractions parallel to the chemical analysis then allows calculation of the concentrations for RDS bulk samples with the four different USLs.

Multi-isotope signatures (Cu, Zn, Pb) of different particle sizes in road-deposited sediments: a case study from industrial area

“…The mobility of RDS on the road surface during rainfall events strongly depends on particle size. Fine particle fractions are easily transported by rainfall, which is important because the concentrations and GSF loading of metals are higher in smaller particles in urban and industrial regions (Lanzerstorfer 2020;Sutherland 2003;Jeong et al 2020d;Zhao et al 2010). Indeed, the fine particles (< 63 µm) had higher Cu, Zn, and Pb concentrations and isotopic values than the coarser fractions (Fig.…”

“…The number of days with a daily rainfall of < 10 mm was 67 days, accounting for 70% of all annual precipitation days. Recently, Lanzerstorfer (2020) suggested that 63 µm would be the upper size limit for runoff studies. Our results also indicate that small particles (< 63 µm) are more suitable for tracing pollution sources than Fig.…”

“…Road surfaces are hot spots for heavy metal pollution because of the accumulation of road-deposited sediments (RDS) via human activities. Road-deposited sediments in urban environments are highly polluted with Cu, Zn, and Pb due to traffic-related activities, such as tire, and brake pad wear and engine emissions (Adamiec et al 2016;Amato et al 2011;Iijima et al 2007;Jeong et al 2020a;Lanzerstorfer 2020). They are a major source of metal pollution in surrounding atmospheric particles, roadside soils, and stream sediments, as they can be readily transported into aquatic and atmospheric environments by stormwater runoff and resuspension by the wind (Bretón et al 2019;Jeong et al 2020b;Khalid et al 2018;Nawrot et al 2020;Popoola et al 2017;Wang and Zhang 2018).…”

Pollution Caused by Potentially Toxic Elements Present in Road Dust from Industrial Areas in Korea

“…Therefore, it is important to establish a strategy to efficiently remove RD in industrial areas to protect the health of employees and residents around industrial complexes as well as to reduce coastal pollution induced by RD wash-off during rainfall events. Runoff and resuspension of RD are important contributors to aquatic environments and ambient particulate matter (PM) in the urban area [7,[58][59][60][61]. Therefore, RD has increased environmental problems, such as water, sediment, and air pollution, and there are concerns regarding human health associated with RD [25,[62][63][64].…”

Human Health Risk Assessment of Heavy Metals in the Urban Road Dust of Zhengzhou Metropolis, China

“…In general, urban areas are more vulnerable to heavy metal contamination compared to rural areas, given the population density and presence of diverse sources of pollution [3]. There has been a worldwide increase in pollutants owing to urban dust, which constitutes a genuine environmental and public health hazard [4].…”