Abstract. 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
polycyclic aromatic hydrocarbons
(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-traffic emission factors are also
determined. In the absence of significant non-combustion emissions, light-duty-traffic
emissions are in good agreement with emissions from chassis
dynamometer measurements. Since recent measurements in Europe including those
from this study are consistent, ratios involving copper (Cu∕Fe and Cu∕Sn)
could be used as brake-wear emissions tracers as long as brakes with Cu
remain in use. Near the Grenoble ring road, where the traffic was largely
dominated by diesel vehicles in 2011 (70 %), the OC∕EC ratio estimated for
traffic emissions was around 0.4. Although the use of quantitative data for
source apportionment studies is not straightforward for the identified
organic molecular markers, their presence seems to well-characterize fresh
traffic emissions.
Identification and quantification of particulate tracers of exhaust and non-exhaust vehicle emissions