AAAR 34th Annual Conference
October 12 - October 16, 2015
Hyatt Regency
Minneapolis, Minnesota, USA
Abstract View
Comprehensive Characterization of Organic Carbon in Diesel Exhaust and Wood Smoke Particulate Matter and Its Correlation to the Toxicity
KLARA ONDRUSOVA, Jana Rousova, Richard Cochran, Alena Kubatova, Annike Irene Totlandsdal, Johan Øvrevik, Per E Schwarze, Marit Låg, University of North Dakota
Abstract Number: 661 Working Group: Aerosol Chemistry
Abstract In atmospheric studies, light absorbing elemental carbon is being blamed for its substantial impact on climate, particularly, on climate cooling. However, many particulate matter-bound organic compounds are also light absorbing, yet this portion of particulate matter (PM), i.e., organic carbon, has not been adequately quantified. Therefore the goal of this study is to estimate the light absorbing portion of several representative PM samples (e.g., wood smoke, diesel exhaust) including a standard reference material and additionally investigate its relationship to the overall organic and elemental carbon content, particularly with regards to their toxicity.
Various methods are used for the characterization of the organic portion of PM. The majority of methods typically start with an extraction, which is often an insufficient sonication with dichloromethane. In this study, representative PM samples were extracted using two different sequences of pressurized organic solvent extractions of varying polarities in addition to hot pressurized water extractions that yielded extracts containing organics of different polarities and functionalities. The PM samples targeted represented matrices of a broad polarity range and of differing organic carbon content. By analyzing all extracts with multiple analytical techniques (GC-FID-MS, thermal optical analysis, UV-Vis spectroscopy), a comprehensive characterization of each sample/extract and subsequent quantification of individual classes of compounds such as acids, aldehydes, alkanes, and polycyclic aromatic hydrocarbons were accomplished. Furthermore, a range of toxicology analyses using bronchial cell lines were performed by Norwegian Institute of Public Health revealing the toxicity of individual extracts.