Use of a mobile laboratory to evaluate changes in on-road air pollutants during the Beijing 2008 Summer Olympics

Abstract. China implemented systematic air pollution control measures during the 2008 Beijing Summer Olympics and Paralympics to improve air quality. This study used a versatile mobile laboratory to conduct in situ monitoring of on-road air pollutants along Beijing's Fourth Ring Road on 31 selected days before, during, and after the Olympics air pollution control period. A suite of instruments with response times of less than 30 s was used to measure temporal and spatial variations in traffic-related air pollutants, including NOx, CO, PM1.0 surface area (S(PM1)), black carbon (BC), and benzene, toluene, the sum of ethylbenzene, and m-, p-, and o-xylene (BTEX). During the Olympics (8–23 August, 2008), on-road air pollutant concentrations decreased significantly, by up to 54% for CO, 41% for NOx, 70% for SO2, 66% for BTEX, 12% for BC, and 18% for SPM1, compared with the pre-control period (before 20 July). Concentrations increased again after the control period ended (after 20 September), with average increases of 33% for CO, 42% for NOx, 60% for SO2, 40% for BTEX, 26% for BC, and 37% for S(PM1), relative to the control period. Variations in pollutants concentrations were correlated with changes in traffic speed and the number and types of vehicles on the road. Throughout the measurement periods, the concentrations of NOx, CO, and BTEX varied markedly with the numbers of light- and medium-duty vehicles (LDVs and MDVs, respectively) on the road. Only after 8 August was a noticeable relationship found between BC and S(PM1) and the number of heavy-duty vehicles (HDVs). Additionally, BC and S(PM1) showed a strong correlation with SO2 before the Olympics, indicating possible industrial sources from local emissions as well as regional transport activities in the Beijing area. Such factors were identified in measurements conducted on 6 August in an area southwest of Beijing. The ratio of benzene to toluene, a good indicator of traffic emissions, shifted suddenly from about 0.26 before the Olympics to approximately 0.48 after the Olympics began. This finding suggests that regulations on traffic volume and restrictions on the use of painting solvents were effective after the Olympics began. This study demonstrated the effectiveness of air pollution control measures and identified local and regional pollution sources within and surrounding the city of Beijing. The findings will be invaluable for emission inventory evaluations and model verifications.

[1]  Binyu Wang,et al.  Air quality during the 2008 Beijing Olympic Games , 2007 .

[2]  A. Wisthaler,et al.  Short-term measurements of CO, NO, NO2, organic compounds and PM10 at a motorway location in an Austrian valley , 2004 .

[3]  R. Harley,et al.  On-road measurement of fine particle and nitrogen oxide emissions from light- and heavy-duty motor vehicles , 1999 .

[4]  H. Oztop,et al.  Evaluation of relationship between meteorological parameters and air pollutant concentrations during winter season in Elazığ, Turkey , 2008, Environmental monitoring and assessment.

[5]  James M. Roberts,et al.  Validation of proton transfer reaction-mass spectrometry (PTR-MS) measurements of gas-phase organic compounds in the atmosphere during the New England Air Quality Study (NEAQS) in 2002 , 2003 .

[6]  J. Hao,et al.  Controlling Vehicular Emissions in Beijing During the Last Decade , 2006 .

[7]  M. L. Laucks Aerosol Technology Properties, Behavior, and Measurement of Airborne Particles , 2000 .

[8]  R. Atkinson Atmospheric chemistry of VOCs and NOx , 2000 .

[9]  J. D. de Gouw,et al.  Measurements of volatile organic compounds in the earth's atmosphere using proton-transfer-reaction mass spectrometry. , 2007, Mass spectrometry reviews.

[10]  Scott Fruin,et al.  Black carbon concentrations in California vehicles and estimation of in-vehicle diesel exhaust particulate matter exposures , 2004 .

[11]  A. Wisthaler,et al.  Long-term measurements of CO, NO, NO2, benzene, toluene and PM10 at a motorway location in an Austrian valley , 2008 .

[12]  D. Westerdahl,et al.  Characterization of on-road vehicle emission factors and microenvironmental air quality in Beijing, China , 2009 .

[13]  J. Hlavay,et al.  Toluene−Benzene Concentration Ratio as a Tool for Characterizing the Distance from Vehicular Emission Sources , 1997 .

[14]  Mamdouh I. Khoder,et al.  Ambient levels of volatile organic compounds in the atmosphere of Greater Cairo , 2007 .

[15]  Jan Willem Erisman,et al.  Variability of particulate matter concentrations along roads and motorways determined by a moving measurement unit , 2004 .

[16]  Ming Fang,et al.  On the time-averaging of ultrafine particle number size spectra in vehicular plumes , 2006 .

[17]  Y. Kim,et al.  Diurnal characteristics of volatile organic compounds in the Seoul atmosphere , 2003 .

[18]  Ernest Weingartner,et al.  A mobile pollutant measurement laboratory—measuring gas phase and aerosol ambient concentrations with high spatial and temporal resolution , 2002 .

[19]  Scott Fruin,et al.  Mobile platform measurements of ultrafine particles and associated pollutant concentrations on freeways and residential streets in Los Angeles , 2005 .

[20]  C. Chan,et al.  Size distributions and condensation growth of submicron particles in on-road vehicle plumes in Hong Kong , 2007 .

[21]  Yuanfang Liu,et al.  Distributions and Source Apportionment of Ambient Volatile Organic Compounds in Beijing City, China , 2005, Journal of environmental science and health. Part A, Toxic/hazardous substances & environmental engineering.

[22]  Wei Shan-feng Pollution Characteristic and Source Analysis of BTEX in Ambient Air of Olympic Gymnasium before and after Traffic Restriction , 2007 .

[23]  Yu Song,et al.  Comparison of receptor models for source apportionment of volatile organic compounds in Beijing, China. , 2008, Environmental pollution.

[24]  E. P. Weijersa,et al.  Variability of particulate matter concentrations along roads and motorways determined by a moving measurement unit , 2004 .

[25]  Liisa Pirjola,et al.  Dispersion of particles and trace gases nearby a city highway: Mobile laboratory measurements in Finland , 2006 .

[26]  Mark S. Zahniser,et al.  Characterization of on-road vehicle emissions in the Mexico City Metropolitan Area using a mobile laboratory in chase and fleet average measurement modes during the MCMA-2003 field campaign , 2006 .

[27]  P. Xie,et al.  [Measurement of atmospheric boundary layer pollutants by mobile lidar in Beijing]. , 2008, Huan jing ke xue= Huanjing kexue.

[28]  Charles E. Kolb,et al.  Chase Studies of Particulate Emissions from in-use New York City Vehicles , 2004 .

[29]  David B. Kittelson,et al.  Nanoparticle emissions on Minnesota highways , 2004 .

[30]  Vlad Isakov,et al.  A Method of Assessing Air Toxics Concentrations in Urban Areas Using Mobile Platform Measurements , 2007, Journal of the Air & Waste Management Association.

[31]  W. B. Knighton,et al.  Measurements of Volatile Organic Compounds Using Proton Transfer Reaction - Mass Spectrometry during the MILAGRO 2006 Campaign , 2008 .

[32]  Simone Meinardi,et al.  Volatile organic compounds in 43 Chinese cities , 2005 .

[33]  S. Balachandran,et al.  Spatial and temporal variation of BTEX in the urban atmosphere of Delhi, India. , 2008, The Science of the total environment.

[34]  D. Brocco,et al.  Determination of aromatic hydrocarbons in urban air of Rome , 1997 .

[35]  Scott C. Herndon,et al.  Vehicle fleet emissions of black carbon, polycyclic aromatic hydrocarbons, and other pollutants measured by a mobile laboratory in Mexico City , 2005 .

[36]  W. B. Knighton,et al.  On-road measurements of volatile organic compounds in the Mexico City metropolitan area using proton transfer reaction mass spectrometry , 2006 .

[37]  Kebin He,et al.  Comparison of vehicle activity and emission inventory between Beijing and Shanghai. , 2007, Journal of the Air & Waste Management Association.

[38]  Ji Han,et al.  Assessment of private car stock and its environmental impacts in China from 2000 to 2020 , 2008 .

[39]  Scott C Herndon,et al.  Characterization of urban pollutant emission fluxes and ambient concentration distributions using a mobile laboratory with rapid response instrumentation. , 2005, Faraday discussions.

[40]  C. Chan,et al.  Air pollution in mega cities in China , 2008 .

[41]  Jiming Hao,et al.  Improving Urban Air Quality in China: Beijing Case Study , 2005, Journal of the Air and Waste Management Association.

[42]  S. C. O T,et al.  Mobile Laboratory with Rapid Response Instruments for Real-Time Measurements of Urban and Regional Trace Gas and Particulate Distributions and Emission Source Characteristics , 2022 .

[43]  A. Hansel,et al.  On-line monitoring of volatile organic compounds at pptv levels by means of proton-transfer-reaction mass spectrometry (PTR-MS) medical applications, food control and environmental research , 1998 .

[44]  Roger Perry,et al.  Vehicle emissions in relation to fuel composition , 1995 .

[45]  V Simon,et al.  The impact of reduction in the benzene limit value in gasoline on airborne benzene, toluene and xylenes levels. , 2004, The Science of the total environment.

[46]  Sun Yang Analysis for Vertical Profile of Atmospheric SO_2 During Air Seriously Polluted Days in Beijing , 2006 .

[47]  Zhan Zhi-gang,et al.  The Study of Pollutant Transport between the Cities in North China , 2004 .

[48]  Lu Wang,et al.  The Longitudinal Dependence of Black Carbon Concentration on Traffic Volume in an Urban Environment , 2008, Journal of the Air & Waste Management Association.

[49]  Min Shao,et al.  Source apportionment of ambient volatile organic compounds in Beijing. , 2007, Environmental science & technology.