Polycyclic Aromatic Hydrocarbons in the Atmosphere of Dajiuhu, Shennongjia, China

Abstract

The concentration, potential source and health risks of 16 polycyclic aromatic hydrocarbons (PAHs) in the atmosphere of Dajiuhu, Shennongjia, China, were studied. Polyurethane foam (PUF) Passive air samplers (PAS) were settled. The results indicated that the total concentrations of 16 PAHs in different samples ranged from 6.94 to 184.23 ng·m-3, with the mean of 30.36 ng·m-3. The dominant compounds were low rings PAHs, such as Phe, Nap, Pyr, Fla, Flu and Ant. Compared with other regions, the PAHs pollution of Dajiuhu atmosphere was at a low level. Higher PAHs concentrations were detected in nearby Deer farm, Dajiuhu peat area and Dajiuhu Wetland Authority. Higher PAHs concentrations were detected in autumn and winter, whereas lower concentrations were detected in spring and summer. Potential pollution sources of PAHs were investigated by diagnostic ratios and backward trajectory analysis, which indicated that coal and biofuel combustion, vehicle emissions and petroleum were the main sources. PAHs of Dajiuhu in air not only came from local emission, but also originated from Hubei, Henan and Hunan's atmosphere transport for most part and long range transport from northwest direction for small part. Health risks assessment results showed that the annual average concentration of total Benzo(a)pyrene-equivalent carcinogenic potency (∑BaPeq) was 0.208 ng·m-3, lower than the value recommended by Ambient Air Quality Standard of China(GB 3095-2012, 1 ng·m-3), indicating a low carcinogenic risk for the local residents.