Traffic emissions of semi-volatile organic compounds analysed by GC GC ToF MS
Ruixin Xu, Mohammed S. Alam, Roy M. Harrison.
Division of Environmental Health and Risk Management, School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham. B15 2TT, U.K.
Epidemiological studies have consistently shown links between adverse health outcomes and airborne particle exposure. Within the urban environment, road traffic, particularly diesel vehicles, is one of the most significant emission sources of particles. Once particles are emitted, they can be modified by a number of physical and chemical processes. Many uncertainties exist regarding the semi-volatile organic component of the particles, which may evaporate and subsequently oxidise to form less volatile compounds which recondense onto solid particles, giving an increased particle mass. Detailed knowledge of the identities and chemical composition of SVOC is elusive, as traditional gas chromatographic methods are unable to separate and characterise complex mixtures adequately, presenting an unresolved complex mixture (UCM) within the chromatogram. In this research, a two-dimensional gas chromatography (GC×GC) was applied to separate compounds in a mixture by volatility and polarity, to offer a more comprehensive understanding of the semi-volatile organic compounds emitted from traffic.