Atmospheric levels of BTEX compounds during the 2008 Olympic Games in the urban area of Beijing.
The hourly concentrations of BTEX (Benzene, Toluene, Ethylbenzene, m,p-Xylene and o-Xylene) in the urban area of Beijing were measured during July-October 2008, covering the periods of the 2008 Olympic Games and Paralympic Games. The atmospheric BTEX were pre-concentrated on Tenax-TA tubes, and analyzed by GC-PID (Gas Chromatography with Photo Ionization Detector) after thermal desorption. During the games, the mean daytime concentrations of benzene, toluene, ethylbenzene, m,p-xylene and o-xylene were 2.37, 3.97, 1.92, 3.51 and 1.90 microg/m3, respectively, and were 52.8%, 63.9%, 56.4%, 56.8% and 46.9%, respectively lower than those after the games. The significantly positive correlation between BTEX and CO as well as the ratio of benzene/toluene suggested that the vehicle exhaust was the major source of BTEX during the whole investigated period. The extremely high ratios of ethylbenzene to m,p-xylene (E/X) were mainly observed at noontime in haze days, indicating that photochemical reactions were highly active under these typical days.
Liu
Junfeng
J
Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
Mu
Yujing
Y
Zhang
Yujie
Y
Zhang
Zhimin
Z
Wang
Xiaoke
X
Liu
Yanju
Y
Sun
Zhenquan
Z
D000393:Air Pollutants / Q000032:analysis* / Q000737:chemistry; D001272:Atmosphere / Q000737:chemistry*; D001555:Benzene Derivatives / Q000032:analysis* / Q000737:chemistry; D002248:Carbon Monoxide / Q000032:analysis; D002681:China; D002947:Cities; D004784:Environmental Monitoring; D038622:Internationality; D010777:Photochemistry; D013177:Sports; D013997:Time Factors; D014050:Toluene / Q000032:analysis; D014505:Urban Population; D001335:Vehicle Emissions / Q000032:analysis; D014835:Volatilization; D014992:Xylenes / Q000032:analysis
D000393:Air Pollutants; D001555:Benzene Derivatives; D001335:Vehicle Emissions; D014992:Xylenes; D014050:Toluene; D002248:Carbon Monoxide