Effect of Pollution Controls on Atmospheric PM2.5 Composition during Universiade in Shenzhen, China

Brian Majestic,Ling-Yan He,Yuan-Xun Zhang,Yu-Qin Wang,Xiao-Feng Huang,Nitika Dewan,Yang Zhang

doi:10.3390/atmos7040057

Abstract

The 16th Universiade, an international multi-sport event, was hosted in Shenzhen, China from 12 to 23 August 2011. During this time, officials instituted the Pearl River Delta action plan in order to enhance the air quality of Shenzhen. To determine the effect of these controls, the current study examined the trace elements, water-soluble ions, and stable lead isotopic ratios in atmospheric particulate matter (PM) collected during the controlled (when the restrictions were in place) and uncontrolled periods. Fine particles (PM2.5) were collected at two sampling sites in Shenzhen: “LG”—a residential building in the Longgang District, with significant point sources around it and “PU”—Peking University Shenzhen Graduate School in the Nanshan District, with no significant point sources. Results from this study showed a significant increase in the concentrations of elements during the uncontrolled periods. For instance, samples at the LG site showed (controlled to uncontrolled periods) concentrations (in ng·m−3) of: Fe (152 to 290), As (3.65 to 8.38), Pb (9.52 to 70.8), and Zn (98.6 to 286). Similarly, samples at the PU site showed elemental concentrations (in ng·m−3) of: Fe (114 to 301), As (0.634 to 8.36), Pb (4.86 to 58.1), and Zn (29.5 to 259). Soluble Fe ranged from 7%–15% for the total measured Fe, indicating an urban source of Fe. Ambient PM2.5 collected at the PU site has an average 206Pb/204Pb ratio of 18.257 and 18.260 during controlled and uncontrolled periods, respectively. The LG site has an average 206Pb/204Pb ratio of 18.183 and 18.030 during controlled and uncontrolled periods, respectively. The 206Pb/204Pb ratios at the PU and the LG sites during the controlled and uncontrolled periods were similar, indicating a common Pb source. To characterize the sources of trace elements, principal component analysis was applied to the elements and ions. Although the relative importance of each component varied, the major sources for both sites were identified as residual oil combustion, secondary inorganic aerosols, sea spray, and combustion. The PM2.5 levels were severely decreased during the controlled period, but it is unclear if this was a result of the controls or change in meteorology.

Highlights

Due to an increase in urbanization and economic growth in China, air pollution has become a severe problem
Increased morbidity and mortality rates and the adverse health effects of particle exposure are predominantly linked to chemical composition of particulate matter (PM) [11,12]
The fact that the wind directions were drastically different during controlled and uncontrolled periods complicate the effects of the controls and this may be another reason why such drastic differences in PM were observed between the two periods

Summary

Introduction

Due to an increase in urbanization and economic growth in China, air pollution has become a severe problem. High PM2.5 levels are associated with human mortality [4,5,6], climate change [7], visibility degradation [8,9], and agricultural yield reduction [10]. Increased morbidity and mortality rates and the adverse health effects of particle exposure are predominantly linked to chemical composition of PM [11,12]. Metals are hard to eliminate and they accumulate in organisms and plants and can cause severe human health related problems and environmental pollution [16,17]. The inhalation of metals is associated with disruption of the nervous system and the functioning of internal organs [18,19,20]

Methods

Results

Conclusion