PAH SOURCE FINGERPRINTS FOR COKE OVENS, DIESEL AND GASOLINE-ENGINES, HIGHWAY TUNNELS, AND WOOD COMBUSTION EMISSIONS

To evaluate the chemical composition (source fingerprint) of the major sources of polyaromatic hydrocarbons (PAHs) in the Chicago metropolit an area, a study of major PAH sources was conducted during 1990-1992. In this study, a modified high-volume sampling method (PS-I sampler) w as employed to collect airborne PAHs in both the particulate and gas p hases. Hewlett Packard 5890 gas chromatographs equipped with the flame ionization and mass spectrometer detectors (GC/FID and GC/MS) were us ed to analyze the samples. The sources sampled were: coke ovens, highw ay vehicles, heavy-duty diesel engines, gasoline engines and wood comb ustion. Results of this study showed that two and three ring PAHs were responsible for 98, 76, 92, 73 and 80% of the total concentration of measured 20 PAHs for coke ovens, diesel engines, highway tunnels, gaso line engines and wood combustion samples, respectively. Six ring PAHs such as indeno(1,2,3-cd)pyrene and benzo(ghi)perylene were mostly belo w the detection limit of this study and only detected in the highway t unnel, diesel and gasoline engine samples. The source fingerprints wer e obtained by averaging the ratios of individual PAH concentrations to the total concentration of categorical pollutants including: (a) tota l measured mass of PAHs with retention times between naphthalene and c oronene, (b) the mass of the 20 PAHs measured in this study, (c) total VOCs, and (d) total PM10. Since concentrations of the above categoric al pollutants were different for individual samples and different sour ces, the chemical composition patterns obtained for each categorical p ollutant were different. The source fingerprints have been developed f or use in chemical mass balance receptor modeling calculations.