Abstract
Emission of nitrated polycyclic aromatic hydrocarbons (nitro-PAH) and their phase distribution were investigated from on-road vehicular emission in a busy road tunnel in Birmingham, United Kingdom. The analytical techniques have been based upon GC/NICIMS for the analysis of particle-associated and vapour nitro-PAH. Samples taken within the Queensway road tunnel in central Birmingham, which should be representative of vehicular emission, indicated the expected presence of 9-nitroanthracene and 1-nitropyrene, the former being present as both particulate and vapour forms, whilst the latter was solely in the particulate phase. 6-nitrobenzo[a]pyrene was also identified in the extracts of particulate matter collected from the tunnel atmosphere. 1-nitronaphthalene and 2-nitronaphthalene were mostly present in the vapour phase. Additionally, separate experiments were performed in the Queensway road tunnel to investigate the significance of any artifact formation of nitro-PAH during sampling at elevated concentrations of nitrogen oxides as usually encountered in road tunnel atmospheres.