Volume 16, No. 12, December 2016, Pages 3164-3174 PDF(1.08 MB)
Characterization of Polycyclic Aromatic Hydrocarbons in Cloud Deposition at Mount Heng in Southern China
Peng-Hui Li1, Yan Wang2, Yu-Hua Li3, Min-Min Yang2, Ming-Hu Sun4, Jia Guo5, You-Ping Shou6, Xianliang Yi7, Lei Wang8, Zhi-Lin Xi1, Zhi-Yong Li9
1 School of Environmental Science and Safety Engineering, Tianjin University of Technology, Tianjin 300384, China
2 School of Environmental Science and Engineering, Shandong University, Jinan 250100, China
3 Shandong Environmental Monitoring Center, Jinan 250101, China
4 Jinan Environmental Protection Bureau, Jinan 250033, China
5 Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
6 Key Laboratory of Environmental Protection Technology on Water Transport, Ministry of Transport, Tianjin Research Institute for Water Transport Engineering, Tianjin 300456, China
7 School of Food and Environment, Dalian University of Technology, Panjin 124221, China
8 Hebei Geological Laboratory, Hebei 071051, China
9 School of Environmental Science and Engineering, North China Electric Power University, Baoding 071000, China
- Cloud samples were collected in free troposphere.
- Particle scavenging was the dominate removal mechanism of PAHs by clouds.
- Multiple sources contributed to the PAH compounds in cloud samples.
Cloud water samples were collected during March to May 2009 at Mount Heng (27°18′N, 112°42′E, 1269 m A.S.L.), a high altitude site in southern China. The samples were analyzed by GS-MS to investigate the distribution, transport pattern, scavenging ratios and possible sources of PAHs. During the observation campaign, the concentration of total (in both particle and dissolved phase) PAHs in cloud water ranged from 323.0–5660 ng L–1, with an average of 1589 ng L–1. BbF was the most abundant compound, contributing to 14.50% of the total PAH concentration, followed by PhA, FluA, Pyr, BaA and Chr. Particle scavenging (Wp) was the dominate removal mechanism, accounting for over 77% of the total scavenging. Significant negative relationship was found between logWp and supercooled vapor pressure of PAHs, suggesting that particle scavenging by cloud water is more efficient for higher molecular weight PAHs. During the observation period, air mass was suggested to mainly originate from south or southeast of China based on back trajectory analysis, while air masses coming from northern China had highest PAH concentration. Diagnostic ratio and principal component analysis indicated that PAHs in cloud water at Mount Heng might originate from multiple sources.
Cloud water; PAHs; Scavenging ratio; Transport pattern; Source analysis.