Quantification and Characterization of Metals in Ultrafine Road Dust Particles

Road dust is an important source of resuspended particulate matter (PM) but information lacking on the chemical composition ultrafine particle fraction (UFP; <0.1 µm). This study investigated metal concentrations in UFP isolated from “dust box” sweepings collected by City Toronto, Canada, using regenerative-air-street sweepers. Dust box samples expressway, arterial and local roads were aerosolized laboratory separated into thirteen size fractions ranging 10 nm to µm (PM10). The accounted for about 2% total mass PM10 (range 0.23–8.36%). Elemental analysis ICP-MS ICP-OES revealed a marked enrichment Cd, Cr, Zn V concentration compared material (nano ratio ≥ 2). contained two times more nine Cr than roads. highest median was observed municipal attributed greater volumes traffic, including light heavy duty vehicles, higher speeds. elevated transition metals are human health concern, given their potential cause oxidative stress lung cells.