Development and testing of sampling methods for the determination of selected semi volatile organic components distributed in aerosols between gas- and particle phase

A new approach of using the Steam Jet Aerosol Collector (SJAC, ECN Netherlands) for the determination of selected semivolatile organic compounds in the ambient aerosol has been investigated. The SJAC, an alternative for artifact susceptible filter based sampling method, is one of condensational growth sampling systems which uses water as a condensational liquid. In order to avoid denuder related artifacts for the determination of the gas phase compounds an extra adsorbent cartridge is applied. Collection of gas phase fraction takes place after particle phase collection; therefore no denuder technique is used. Separating efficiency for different, artificially generated hydrophobic particles was examined. In order to estimate the amount of bias caused by the transfer of components from gas phase to the particle fraction, streams of individual organic compounds with different polarity in synthetic air were examined. Laboratory tests showed negligible amounts of gas phase material measured in the particle fraction and high collection efficiency for hydrophobic particles. The outdoor study aimed for field comparisons of the modified SJAC with different kind of available (denuder)/filter/adsorber sampling methods for determination of gaseous and particulate PAH concentration. Results from this sampling campaign showed that due to the temperature sensitivity of the SJAC and possible degradation of the examined components further developments are necessary.