Identification and quantification of particulate tracers of exhaust and non-exhaust vehicle emissions

Abstract

<p><strong>Abstract.</strong> In order to identify and quantify key-species associated with non-exhaust emissions and exhaust vehicular emissions a large comprehensive dataset of particulate species has been obtained thanks to simultaneous near-road and urban background measurements coupled with detailed traffic counts and chassis dynamometer measurements of exhaust emissions of a few in-use vehicles well-represented in the French fleet. Elemental Carbon, brake-wear metals (Cu, Fe, Sb, Sn, Mn), n-alkanes (C19–C26), light molecular weight PAHs (Pyrene, Fluoranthene, Anthracene) and two hopanes (17α21βNorhopane and 17α21βhopane) are strongly associated with the road traffic. Traffic-fleet emission factors have been determined for all of them and are consistent with most recent published equivalent data. When possible, light-duty and heavy-duty duty traffic emission factors are also determined. Most of the first ones are in good agreement with emissions from chassis dynamometer measurements in absence of significant non-combustion emissions. This study has shown that ratios involving copper (mainly Cu/Fe and Cu/Sn) could be used to trace brake-wear emissions as they seem to be roughly constant in Europe and as longer as Cu-free brake are not largely spread. In France where the traffic was largely dominated by diesel vehicles in 2011 (70 %), the OC/EC ratio typical of traffic emissions was around 0.44. On the contrary, the use of quantitative data for source apportionment studies is not straightforward for the identified organic molecular markers; while, their presence seems to well-characterized fresh traffic emissions.</p>

Pollution characteristics and human health risks of PM2.5-bound heavy metals: a 3-year observation in Suzhou, China

“…The highest concentration of Al among these heavy metals suggested a predominant contribution from crustal sources such as fugitive dust to the fine aerosols in Suzhou (Ma et al, 2019 ; Xu et al, 2021 ). While the dominance of Mn and Pb could be attributed to coal combustion (Deng et al, 2014 ) and traffic emissions including exhaust and non-exhaust emissions (Charron et al, 2018 ). Other heavy metals were ranked as: Cr > Sb > As > Ni > Se > Cd > Hg > Tl.…”

“…However, it was noteworthy that the concentration of Cr(VI) in Suzhou was 0.66 ng m −3 , which was lower than some cities of Northern China such as Beijing (2.5 ng m −3 ) (Fan et al, 2021 ), Baoding (8.3 ng m −3 ) (Liu et al, 2018 ), and some cities of Eastern China such as Shanghai (3.2 ng m −3 ) (Chen et al, 2008 ), and some cities of Southern China such as Xiamen (3.7 ng/m 3 ) (Wang et al, 2017 ), and some other Asian cities such as Siheung (2.43 ng m −3 ) (Lee et al, 2022 ), but more than twenty times higher than the China standards of 0.025 ng m −3 . Many studies showed that the sources of Cr included brake and engine wear (Charron et al, 2018 ), industrial metalworking activities (Dai et al, 2015 ), and the incineration of plastic materials.…”

“…One possible reason was that the contribution from coal combustion emissions to atmospheric Cd and Pb was not considered unique. In addition to coal combustion, sources of Cd and Pb included brake and engine wear and motor oil combustion (Charron et al, 2018 ). In order to control the speed of the COVID-19, the local authorities advised citizens to drive to work, resulting in elevation in traffic pollution emissions including Cd and Pb emissions.…”

Study on the Physical and Chemical Characteristics and Sources of Atmospheric Single Particles in Weifang During the 2022 Winter Olympic Games and the Winter Paralympic Games

“…Most of the spherical iron particles are combustion processes of steelmaking containing chromium. The metal particles of iron may come from the emissions of diesel engines, chromium oxide may exist in the filler of brake linings and can also be burned from lubricating oil [18], tin-rich particles may come from the fuel combustion of port vessels [19], titanium balls may come from the pigment manufacturing process [20], and irregular titanium sheets may come from road dust and wear of tires and brakes [21]. Sulfur-rich particles are irregular in shape and volatile under the electron beams, usually forming a "foam-like" structure.…”

“…7. Most iron balls come from the combustion process of steelmaking [18], while titanium balls come from pigment manufacturing [20]. The proportion of iron balls in the samples during the Winter Olympic Games is higher than that after the Winter Paralympic Games, and the average amount of particulate matter per day is lower than that after the Winter Paralympic Games, which indicates that the control effect of steel making industry is better during the Winter Olympic Games, but the control effect of other pollution sources is better, resulting in a higher proportion; The proportion of titanium balls in the samples of the Winter Olympic Games is higher than that before and after the Winter Olympic Games, but the average amount of particulate matter per day is lower than that before and after the Winter Olympic Games.…”