Part II: PM2.5 and Polychlorinated Dibenzo-p-dioxins and Dibenzofurans (PCDD/Fs) in the Ambient Air of Northern China

Jin Xing, Kangping Cui , Haiyan Tang, Wen-Jhy Lee, Lin-Chi Wang, Jinning Zhu , Qianli Huang

Abstract

During 2014–2016, this study investigated the atmospheric PM2.5, RM, PM2.5/PM10, PCDD/Fs-WHO2005-TEQ, and PM2.5-bound total-PCDD/Fs-WHO2005-TEQ content of 22 cities in northern China. In general, the more highly industrialized cities had higher PM2.5 concentrations. The lowest three-year average concentrations of PM2.5 occurred at Lhasa and Qiqihar, and were 25.2 and 36.7 μg m–3, respectively, while the highest concentrations of PM2.5 occurred at Baoding and Shijiazhuang, and were 106 and 102 μg m–3, respectively. From 2015 to 2016, the PM2.5 concentrations of most cities decreased, but those of several others (Shijiazhuang, Taiyuan, Yinchuan, Lhasa, Sinning, Urumqi, Weinan and Xian) increased, suggesting that the air quality of these was still not well controlled. The average of RM values of the 22 cities were 7.2, 6.5, and 6.1 in 2014, 2015 and 2016, respectively, which means the PM2.5 concentrations in northern China were much higher than the WHO air quality regulated standard (10 μg m–3). A city with a higher PM2.5 concentration always had a higher PM2.5/PM10 ratio. Among the 22 cities, the six highest three-year averages of total-PCDD/Fs-WHO2005-TEQ concentrations were 0.107, 0.102, 0.095,0.092,0.085 and 0.077 pg-WHO2005-TEQ m–3 in Shijiazhuang, Baoding, Zhengzhou, Jinan, Linyi and Xian, respectively; the six lowest three-year averages of total-PCDD/Fs-WHO2005-TEQ concentrations were 0.036, 0.037, 0.045, 0.055, 0.056 and 0.060 pg-WHO2005-TEQ m–3 in Qiqihar, Lhasa, Dalian, Harbin, Changchun and Hohhot, respectively. The PM2.5-bound total PCDD/Fs-WHO2005-TEQ content of 12 cities (six cities with higher PM2.5 concentration and six with lower PM2.5 concentration), during 2014, ranged between 0.444 and 1.000 ng-WHO2005-TEQ g–1 and averaged 0.672 ng-WHO2005-TEQ g–1. The PM2.5 concentrations, RM values and PCDD/Fs-WHO2005-TEQ concentrations in the cities of northern China are higher than those in the south, indicating that the air quality in the north is worse than in the south. The results of this study provide a theoretical basis for proposing air pollution control strategies and improving the atmospheric environment in China.
Keywords: PM2.5 PCDD/Fs PM2.5/PM10ratio TEQ Northern China Cities

Source: nbsp; Volume: 17 , Issue: 8 , Pages: 2010-2026 DOI: 10.4209/aaqr.2017.06.0211