10th International Aerosol Conference
September 2 - September 7, 2018
America's Center Convention Complex
St. Louis, Missouri, USA

Abstract View


Detection of Polyaromatic Hydrocarbons, as Well as Positive and Negative Inorganic Ions from the Same, Individual Particle

Johannes Passig, Julian Schade, Robert Irsig, Sven Ehlert, Martin Sklorz, RALF ZIMMERMANN, Helmholtz Zentrum Munich and Rostock University

     Abstract Number: 676
     Working Group: Aerosols and Health - Connecting the Dots

Abstract
Air pollution represents the largest environmental risk to health worldwide. Herein inhalation of polyaromatic hydrocarbons (PAHs) is an established cause of morbidity and mortality, but little is known about their detailed distribution in ambient particulate matter (PM). These details, e.g. the PAHs mixing state, are crucial for potential effects since PAHs may be equally distributed over a large particle ensemble or could be confined to a specific particle sub-type with high concentration producing strong local effects in the lung. Furthermore, PAHs are considered for taking an active role in secondary aerosol formation. As a consequence, novel aerosol characterization techniques that address PAHs on a single particle basis while providing information on their potential source are highly desired.

On-line techniques for individual particle profiling typically base on the Aerosol Time-of-Flight (ATOF) technique, which applies laser-desorption/ionization (LDI) of individual particles in the ion source of a bipolar mass spectrometer. Particle LDI is often limited to refractory inorganic compounds, while particle-bound molecules are typically fragmented. Approaches targeting on PAHs could not preserve the normal LDI-information on the inorganic bulk composition. Recently, we were able to complement the PAH information by positive inorganic ions from LDI using a complex laser ionization scheme. Here we present a route to obtain the full LDI information of both positive and negative inorganic ions in combination with PAHs. Thus, a conventional source apportionment that bases on ions of either charge can be combined with a fully-fledged PAH mass spectrum of individual particles.