Nationwide increase of polycyclic aromatic hydrocarbons in ultrafine particles during winter over China revealed by size-segregated measurements

作者：Qingqing Yu, Xiang Ding, Quanfu He, Weiqiang Yang, Ming Zhu, Sheng Li, Runqi Zhang, Ruqin Shen, Yanli Zhang, Xinhui Bi, Yuesi Wang, Ping’an Peng, Xinming Wang · 发表于：Atmospheric chemistry and physics · 年份：2020 · DOI：10.5194/acp-20-14581-2020 · 被引用次数：45 · 研究领域：Air Quality and Health Impacts、Toxic Organic Pollutants Impact、Atmospheric chemistry and aerosols

Abstract. Polycyclic aromatic hydrocarbons (PAHs) are toxic compounds in the atmosphere and have adverse effects on public health, especially through the inhalation of particulate matter (PM). At present, there is limited understanding of the size distribution of particulate-bound PAHs and their health risks on a continental scale. In this study, we carried out a PM campaign from October 2012 to September 2013 at 12 sampling sites simultaneously, including urban, suburban and remote sites in different regions of China. Size-segregated PAHs and typical tracers of coal combustion (picene), biomass burning (levoglucosan) and vehicle exhaust (hopanes) were measured. The annual averages of the 24 total measured PAHs (∑24PAHs) and benzo[a]pyrene (BaP) carcinogenic equivalent concentration (BaPeq) ranged from 7.56 to 205 ng/m3 with a mean of 53.5 ng/m3 and from 0.21 to 22.2 ng/m3 with a mean of 5.02 ng/m3, respectively. At all the sites, ∑24PAHs and BaPeq were dominant in the ultrafine particles with aerodynamic diameter < 1.1 µm, followed by those in the size ranges of 1.1–3.3 µm and > 3.3 µm. Compared with southern China, northern China witnessed much higher ∑24PAHs (87.36 vs. 17.56 ng/m3), BaPeq (8.48 vs. 1.34 ng/m3) and PAHs' inhalation cancer risk (7.4 × 10−4 vs. 1.2 × 10−4). Nationwide increases in both PAH levels and inhalation cancer risk occurred in winter. The unfavorable meteorological conditions and enhanced emissions of coal combustion and biomass burning together...