[Pollution characteristics of polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans and polychlorinated biphenyls in PM2.5 of Hangzhou City during winter].
In order to evaluate the distributions and concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and polychlorinated biphenyls (PCBs) in aerosol, PM2.5 samples were collected concurrently at five sites in January 2014 in Hangzhou. The analytes were analyzed with isotope dilution and high resolution gas chromatography/high resolution mass spectrometry (HRGC/HRMS) based on US EPA 1613B method and US EPA 1668B method. The results showed that the mass concentrations of PM2.5 were in the range of 85-168 μg/m3, which were much higher than the national quality standard. The values suggested that the PM2.5 pollution was relatively serious in Hangzhou City, yet it has been improved when compared with the results of 2004. The toxic equivalent quantities (TEQs) of PCDD/Fs in PM2.5 were in the range of 0.277-0.488 pg I-TEQ/m3, which were much higher than the results in 2004. Octachlorodibenzo-p-dioxin (OCDD) accounted for a large proportion to the total concentrations in PCDD/Fs, while 2,3,4,7,8-pentachlorodibenzofurans (2,3,4,7,8-PeC- DF) contributed the highest to the TEQ. The values of PCBs and dioxin-like PCBs (DL-PCBs) varied from 2.9-8.1 pg/m3 and 2.6-6.1 fg WHO-TEQ/m3, respectively. PCB-28 was the most abundant contributor to the concentrations of PCBs, while PCB-126 contributed the highest to the TEQ of DL-PCBs. Gas-particle distributions of PCDD/Fs and PCBs shows that PCDD/Fs were mainly distributed in the particle phase, but PCBs were preferably adsorbed in the gas phase.
Mufei
M
Li
Jinsong
J
Liu
Xin
X
Zhou
Guohua
G
Zhu
Hongping
H
Gong
Bei
B
Chen
Ling
L
Wang
Junjun
J
Sun