|PEINADO, PORFIRIO - University Of Texas|
Submitted to: American Chemical Society SE/SW Regional Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 11/4/2009
Publication Date: 11/7/2009
Citation: Peinado, P., Stout, J.E. 2009. Chemistry of Airborne Particulate Matter in the Western Plains of Texas Using PIXE Analysis[abstract]. American Chemical Society SE/SW Regional Meeting. November 4-7, 2009. El Paso, Texas.
Technical Abstract: Aerosol samples on polycarbonate filters were collected daily (for 24 hour periods) over several years in Lubbock, Reese Center, and Big Spring in the Southern High Plains region of western Texas, a region known for frequent dust storms. Twenty-seven filter samples representing a variety of particle size modes (PM10, PM2.5, TSP) and air quality conditions (dust storm, anthropogenic pollution episodes of several kinds, and clean air) were analyzed by proton-induced X-ray emission spectrometry (PIXE). Silicon, aluminum, iron, potassium and titanium dominated during dust storms and in the coarse mode (PM 10, TSP); sulfur dominated during anthropogenic pollution episodes and in the fine (PM 2.5) mode, especially in Lubbock. A mixture of both aerosol types was present even during “unpolluted conditions,” often with higher crustal element concentrations in the coarse mode and higher sulfur and chlorine concentrations in the fine mode. Chlorine, calcium, copper and zinc concentrations as a percentage of total mass were highest during non-dust-storm conditions; rubidium and zirconium were only detected during dust events. The crustal element composition of aerosols generally matched published data for local soils, except for lower potassium concentrations and greater Mn/Fe ratios in aerosol samples. The Al/Si ratio in the aerosols increased with intensity (average wind speed) of dust events. These data provide an initial assessment of the chemistry of airborne particulate matter in the West Texas plains during dusty and non-dusty conditions.