Source apportionment of airborne PAH in an urban environment

Abstract

Urban environments constitute one of the main focuses of anthropogenic polycyclic aromatic hydrocarbons (PAH) generation. A study regarding PAH bounded to the airborne particulate matter PM10 was carried out in Zaragoza city, Spain during 2010-2011. The concentrations of 19 PAH were analyzed by gas chromatography with mass spectrometry mass spectrometry detection. The sources of PAH to ambient air in Zaragoza were determinad by using the UNMIX model in order to discern qualitatively and quantitatively the main pollution sources affecting the sampling site. When the total PAH concentrations obtained experimentally were compared to the total PAH concentrations modeled by the UNMIX, the correlation was excellent. A total of tour sources were identified by the model related to different anthropogenic pollution sources where the heavy-duty diesel vehicles and the traffic emissions factors were identified as the major contributing sources of PAH. Episodes were classified as a function of BaP concentrations, one of the most carcinogenic PAH according to Directiva 2004/107/EC and the contribution of pollution sources was compared to the average PAH episodes. The highest BaP concentrations, involving a higher risk for human health, were produced during the cold season showing a remarkable increase in the heavy-duty diesel vehicles factor contribution.