Size Resolved Atmospheric Aerosol Composition by Raman Microspectroscopy

Sarah D. Brooks, Peter Deng, Lijun Zhou, and Naruki Hiranuma

Texas A&M University

     Abstract Number: 746
     Last modified: May 14, 2010

Abstract
Atmospheric particle composition is an important factor for understanding the impacts of particulate emissions on human health, and yet most current methods for quantifying the affects of coarse particulates rely solely on mass. Raman microspectroscopy (RM) is an ideal new technique for characterizing the complex composition of particles since it is sensitive to organic compounds, inorganic salts, soil and mineral dust, and even biogenic components such as pollen and fungal spores which may be present in atmospheric aerosols. In addition, RM can be used to evaluate the distribution of components within individual particles as well as the degree of internal mixing in a population can be measured. Field measurements of atmospheric particulates collected in urban and rural locations vary greatly in size and composition. Measurements include in-situ determination of aerosol concentrations and sizes and collection of aerosol samples (in the size ranges of PM10, PM2.5, and PM10-2.5) for RM analysis. Results will be used determine whether a refinement in current particle matter health assessments which considers chemistry is needed, and if so, to develop a strategy to implement our results into future assessments.