Mutagenicity of PM10-bound PAHs from non-exhaust sources

Abstract

Road traffic is a major source of airborne particles. While exhaust emissions have been deeply scrutinised, non-exhaust emissions deserved less attention despite their rising contribution to particle emissions from traffic. The mutagenicity of particulate matter (PM10) samples from wear between pavements and tyres and from road dust resuspension was determined by the Ames test with two Salmonella typhimurium strains (TA98 and TA100) with or without metabolic activation. After sequential extraction of PM10 samples in dichloromethane and methanol, the extracts were separated via flash chromatography and the subfraction that contained polycyclic aromatic compounds (PAHs) was used in the assays. Additionally, the samples were analysed by gas chromatography-mass spectrometry (GC-MS). The analysed extracts contained predominantly high molecular weight PAHs with varying concentrations. The non-exhaust traffic-related source samples did not reveal mutagenic potential at the doses examined. Given the compositional complexity of the samples, aggregating multiple metals and organic compounds of different polarities, an integrated assessment of the toxicity of non-exhaust particles should include other in vitro toxicity assays.

Biological effects of Tire and Road Wear Particles (TRWP) assessed by in vitro and in vivo studies – A systematic review

“…TD also produced severe malformations in developing X. laevis embryos (Gualtieri et al, 2005a) First, it should be noted that studies on the inhalation toxicity of TRWP in mammalian models remain quite sparse. While some works do not find any harm induced by TRWP (Karlsson et al, 2008;Kreider et al, 2012;Lehner et al, 2020;Vicente et al, 2022), others clearly indicate a significant toxicological effect (Beretta et al, 2007;Gottipolu et al, 2008;Gualtieri et al, 2008Gualtieri et al, , 2005aGualtieri et al, , 2005bGustafsson et al, 2008;Karlsson et al, 2011Karlsson et al, , 2006Lindbom et al, 2007Lindbom et al, , 2006Liu et al, 2022;Mantecca et al, 2010Mantecca et al, , 2009aMantecca et al, , 2009bPoma et al, 2019). From the analysis of these papers, we can conclude that the TRWP effects may be mediated mainly by a pro-inflammatory response and oxidative stress, as described below.…”

“…The toxicity of TRWP has been associated mainly with the metallic constituents of non-exhaust PM but some studies have shown that these particles also contain polycyclic aromatic hydrocarbons (PAHs) (Vicente et al, 2022), many of which are potent mutagens and carcinogens. Therefore, metals (in particular Zn, Cd and Cu) and polycyclic aromatic hydrocarbons (PAHs) are key components driving the toxicity observed, which is consistent with the general literature on ambient PM.…”