Spatial distribution and source apportionment of atmospheric polycyclic aromatic hydrocarbons in the Pearl River Delta, China

Air samples were collected using polyurethane foam passive samplers from 26 air-monitoring stations located in the Pearl River Delta, China and two in Shaoguan City in Guangdong Province in 2015 to investigate the occurrence and distribution of priority polycyclic aromatic hydrocarbons (PAHs). Sixteen PAHs were identified and 15 of them (except for naphthalene) were quantified at a total concentration (∑15PAHs) that varied from 3.56 ng/m3 to 37.2 ng/m3 (average value 19.8 ± 9.69 ng/m3). The results indicated that PAHs with 3-4 benzene rings accounted for approximately 80% of all PAH compounds, among which phenanthrene and fluoranthene were the predominant components. Diagnostic parameters suggested that the possible sources of PAHs in the Delta region were mixed of petrogenic and pyrogenic sources from fuel/biomass/coal combustion. Based on the measured PAHs concentrations, the Carcinogenic Potency Risk (BaPeq) and Inhalation Cancer Risk (ICR) were assessed, and indicated that two air samples from Guangzhou and one from Foshan exceeded the BaPeq limit (1 ng/m3), whereas all samples from the 28 sampling locations exceeded the health-based guideline concentration for ICR. The results of this research suggest that a potential human health risk exists from PAHs in the study area via the respiration and inhalation pathway.