Characterization of Asphalt Fume Composition under Simulated Road Paving Conditions by GC/MS and Microflow LC/Quadrupole Time-of-Flight MS
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- 作者：Jin Wang ; Daniel M. Lewis ; Vincent Castranova ; David G. Frazer ; Travis Goldsmith ; Seth Tomblyn ; Janet Simpson ; Samuel Stone ; Ali Afshari ; and Paul D. Siegel
- 刊名：Analytical Chemistry
- 出版年：2001
- 出版时间：August 1, 2001
- 年：2001
- 卷：73
- 期：15
- 页码：3691 - 3700
- 全文大小：155K
- 年卷期：v.73,no.15(August 1, 2001)
- ISSN：1520-6882
文摘
A highly sensitive, selective, and reliable analytical methodhas been developed and validated for characterization ofasphalt fume generated under simulated road pavingconditions. A dynamic asphalt fume generation systemwas modified to provide consistent test atmospheres atsimulated asphalt road paving conditions. In the processof fume generation, asphalt was initially preheated in anoven to 170 
C, pumped to a large kettle, which maintained the asphalt temperature between 150 and 170 C,and then transferred to the generator. The fume wasconducted from the generator to an exposure chamberthrough a heated transfer line. Characterization of theasphalt fume test atmospheres included the following: (1)determination of the consistency of the asphalt aerosolcomposition within the generation system; (2) quantification of total organic matter of the asphalt fume by electronimpact ionization of isotope dilution gas chromatography/mass spectrometry); and (3) identification of individualpriority polycyclic aromatic hydrocarbons (PAHs) inasphalt fume by selected ion monitoring. With the developed method, asphalt fumes could be characterized intothree fractions: (1) filter collection of a large molecularsize fraction over a range of mass-to-charge (m/z) ratiosof 173-309; (2) XAD-2 trapping of a medium molecularsize fraction over a range of m/z ratios of 121-197; and(3) charcoal trapping of a small molecular size fractionthat contained mainly the volatile vapor fraction over arange of m/z ratios of 57-141. Total organic matter ofthe asphalt fume was quantified over the 5 exposure days.Sixteen specific priority PAHs were monitored and identified. These PAHs were determined at trace levels on thefilter fraction. A novel approach, which utilizes collision-induced dissociation of fragmentation pathway leading toa characteristic fragmentation pattern by coupling microflow liquid chromatography to atmospheric pressurechemical ionization of quadrupole time-of-flight massspectrometry, was used to further clarify the trace amountof key components present in simulated road pavingasphalt fumes. These results demonstrate that asphaltfume composition could be characterized and specificpriority PAHs could be identified by this method. Themajor advantages of this method are its highly sensitivity,selectivity, and reliability for chemical hazard characterization in a complex mixture. This method is suitable forsupport toxicity studies using simulated occupationalexposure to asphalt fumes.
C, pumped to a large kettle, which maintained the asphalt temperature between 150 and 170 C,and then transferred to the generator. The fume wasconducted from the generator to an exposure chamberthrough a heated transfer line. Characterization of theasphalt fume test atmospheres included the following: (1)determination of the consistency of the asphalt aerosolcomposition within the generation system; (2) quantification of total organic matter of the asphalt fume by electronimpact ionization of isotope dilution gas chromatography/mass spectrometry); and (3) identification of individualpriority polycyclic aromatic hydrocarbons (PAHs) inasphalt fume by selected ion monitoring. With the developed method, asphalt fumes could be characterized intothree fractions: (1) filter collection of a large molecularsize fraction over a range of mass-to-charge (m/z) ratiosof 173-309; (2) XAD-2 trapping of a medium molecularsize fraction over a range of m/z ratios of 121-197; and(3) charcoal trapping of a small molecular size fractionthat contained mainly the volatile vapor fraction over arange of m/z ratios of 57-141. Total organic matter ofthe asphalt fume was quantified over the 5 exposure days.Sixteen specific priority PAHs were monitored and identified. These PAHs were determined at trace levels on thefilter fraction. A novel approach, which utilizes collision-induced dissociation of fragmentation pathway leading toa characteristic fragmentation pattern by coupling microflow liquid chromatography to atmospheric pressurechemical ionization of quadrupole time-of-flight massspectrometry, was used to further clarify the trace amountof key components present in simulated road pavingasphalt fumes. These results demonstrate that asphaltfume composition could be characterized and specificpriority PAHs could be identified by this method. Themajor advantages of this method are its highly sensitivity,selectivity, and reliability for chemical hazard characterization in a complex mixture. This method is suitable forsupport toxicity studies using simulated occupationalexposure to asphalt fumes.