Polycyclic aromatic hydrocarbons (PAHs) in air associated with particles PM2.5 in the Basque Country (Spain)

Abstract

The polycyclic aromatic hydrocarbons (PAHs) are a group of persistent pollutants that are globally distributed. The objectives of this study are as follows: (1) to analyze the levels of the priority PAHs in the PM2.5 fraction of air: naphthalene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benzoanthracene, chrysene, benzo(b)fluoranthene, benzo(k)fluoranthene, benzo(a)pyrene, dibenzoanthracene, benzo(g,h,i)perylene, indenepyrene, acenaphthylene, in two urban industrial areas of the province of Gipuzkoa (Basque Country, Spain), (2) to describe seasonal variation, and (3) to identify the source of PAHs. The ∑PAH concentrations ranged from 0.85 to 9.86 ng/m3. We found statistical differences between sites of sampling (p < 0.05), with higher values in Azpeitia. The median value of benzo(a)pyrene was 0.05 ng/m3 (ranged from 0.05 to 1.12 ng/m3), lower than the threshold set by the European legislation. Statistical differences were found (p < 0.05) in relation to seasonal variation, with the highest levels registered in winter and in autumn. PAH ratios and principal component analysis (PCA) revealed that probably the vehicular emissions are the predominant source of PAHs.