Novel concepts for addressing composition as well as climate- and health-impact of airborne particulate matter: From Single Particle Mass Spectrometry to on-line Air-Liquid-Interface human lung cell culture exposure

Air pollution by fine particle matter (PM) is known to be the most severe environmental health-risks worldwide (WHO, 2001) and also has a very large climate impact. The investigation of adverse effect mechanisms of aerosols including the impact of the important organic PM fraction is a complex task with many scientific and technological challenges. New analytical methods and scientific instruments for an effect-directed characterization of the chemical composition as well as important physical properties of aerosol particles (e.g., the internal/external mixing state of toxicants within the particle ensemble, optical properties, better source apportionment approaches) can help to better fulfill this task. In addition, biological approaches for investigation the adverse toxic effects of aerosols are needed. In this context, improved analytical approaches for both, the chemical and the toxicological characterization of aerosols are needed. In the lecture, rapid aerosol characterization methods based on Photo Ionization Mass Spectrometry (PIMS) are discussed. For on-line measurements a novel improved Single Particle Mass Spectrometer (SPMS) has been developed. This system allows the real-time measurement and mixing-state analysis for inorganic compounds (metals/soot/ salts/minerals) as well as for organic compounds (PAH, oxalate etc.) on single aerosol particle basis, by using resonance ionization processes. Application examples on wildfire and marine aerosols are presented. Another approach is to analyze the organic fingerprints evolving from a PM-loaded filter punch during a Thermal-Optical Carbon Analysis (TOCA, for determination of Elemental Carbon (EC) and Organic Carbon (OC)). For this a TOCA analyzer system was hyphenated to a Photoionization Mass Spectrometer (TOCA-PIMS). The approach is introduced and application examples are given. Finally, examples of Air-Liquid-Interface (ALI) exposures of human lung cell-cultures for evaluating the toxicological impact of emission aerosols are presented (e.g., bio mass burning, vehicle emissions). Particularly interesting I this context  is the investigation of the impact of atmospheric ageing. In conclusion it is demonstrated that the development of improved measurement approaches still is very much needed to understand the mechanisms which are inducing the adverse impacts of atmospheric aerosols.