title: Reduction of atmospheric polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) during the 2008 Beijing Olympic games.
abstract: A total of 120 air samples were collected at three urban and one rural location in Beijing, China in the summers of 2007-2010, and before, during, and after the Beijing 2008 Olympic Games (BOG), in order to assess the effectiveness of long-term and short-term emission-control measures in reducing polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in the atmosphere. During the BOG (August, 2008), the PCDD/Fs concentrations decreased to an average value of 1150 fg m(-3) (63 fg I-TEQ m(-3)), which was reduced by approximately 70% from the average in 2007 and by 29% from that in July 2008, before the Olympic event began. Although 2009-2010 levels of PCDD/Fs were significantly higher than 2008, the overall temporal trend was decreasing for summer months during the sampling campaign period. The apparent half-lives of atmospheric PCDD/Fs were estimated to be 3.2-5.8 years by statistically regressing the logarithm PCDD/Fs concentrations versus the number of years passed since 2006. The air concentrations of total suspended particulates (TSP) during the BOG ranged between 135 and 183 μg m(-3), showing a 52% reduction from 2007 and 26% decrease from those prior to the Olympic event. No significant relationships were found between meteorological parameters (temperature, humidity, and wind speed) and PCDD/Fs or TSP during the BOG, whereas the PCDD/Fs concentrations were significantly dependent on the air quality (p < 0.05, positive against TSP and negative against visibility). This work is one of few temporal trend studies of atmospheric PCDD/Fs in mainland China, and provides unique insight into the effects of large-scale control measures in improving air quality and reducing one of the most ubiquitous and toxic organic pollutants in the environment.
authors.affiliation: State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences , Beijing 100085, People's Republic of China.
authors.forename: Yingming
authors.initials: Y
authors.lastname: Li
authors.forename: Thanh
authors.initials: T
authors.lastname: Wang
authors.forename: Pu
authors.initials: P
authors.lastname: Wang
authors.forename: Lei
authors.initials: L
authors.lastname: Ding
authors.forename: Xiaomin
authors.initials: X
authors.lastname: Li
authors.forename: Yawei
authors.initials: Y
authors.lastname: Wang
authors.forename: Qinghua
authors.initials: Q
authors.lastname: Zhang
authors.forename: An
authors.initials: A
authors.lastname: Li
authors.forename: Guibin
authors.initials: G
authors.lastname: Jiang
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D000397:Air Pollution / Q000517:prevention & control / Q000706:statistics & numerical data*; D001272:Atmosphere / Q000737:chemistry*; D001572:Benzofurans / Q000032:analysis*; D002681:China; D003247:Conservation of Natural Resources; D000072338:Dibenzofurans, Polychlorinated; D004784:Environmental Monitoring; D000072317:Polychlorinated Dibenzodioxins / Q000031:analogs & derivatives* / Q000032:analysis; D013177:Sports
chemical_list: D000393:Air Pollutants; D001572:Benzofurans; D000072338:Dibenzofurans, Polychlorinated; D000072317:Polychlorinated Dibenzodioxins