Characterization of atmospheric lead-containing particles in Guangzhou, China, by Single Particle Aerosol Mass Spectrometry
PENG Long;LIN Qin-hao;YANG Yu-xiang;LIAN Xiu-feng;FU Yu-zhen;ZHANG Guo-hua;BI Xin-hui;WANG Xin-ming;SHENG Guo-ying;State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Resources Utilization and Protection, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences;University of Chinese Academy of Sciences;
A single particle aerosol mass spectrometer was used to characterize the particle types, mixing state, and sources of lead-containing particles in different seasons in Guangzhou, China. The results showed that the seasonal average number fraction of lead-containing particles followed the order summer(3.6%) fall(2.4%) winter(1.8%) spring(1.0%). The lead-containing particles were classified as K-Pb, EC-Pb, Pb-rich, Metal-Pb, and Dust-Pb, which may have originated from coal combustion, steel and metal smelting, and dust. The different types of lead-containing particles had distinct mixing states with secondary species, such as sulfate and nitrate. Pb-rich and Dust-Pb particles were mainly mixed with nitrate, while the other three types were mixed with both sulfate and nitrate. The main type was K-Pb, which accounted for 50% of the lead-containing particles, followed by Pb-rich(~15%) and Metal-Pb(5%~10%) in all four seasons. Notably, the contribution of EC-Pb was much higher in spring than in the other seasons. Dust-Pb was only detected in winter due to long-range transport of air carrying dust particles from northern China. A Pb contamination event was observed during which the daily number fraction of lead-containing particles approached 14%. This event could be explained by particle transport from steel and metal smelter emissions in northern and northeastern Guangzhou. This study provides a reference for the assessment of the effects of atmospheric lead on the ecological environment and human health.