Source apportionment of ambient fine particulate matter (PM(2.5)) in Corpus Christi by comparing principal component analysis and unmix receptor models (Texas)

The PM2.5 particles are of importance as they can aggravate the existing respiratory problems or even cause some new ones. Corpus Christi region under the influence of industrial and demographic growth has a high potential to violate the standards within the next few years. Hence, speciation is conducted at (Continuous Air Monitoring Station) CAMS199 and CAMS314 sites in Corpus Christi. The elemental species considered in this analysis are As, Br, Cr, Cu, Fe, Pb, Mn, Mo, Ni, Sn, V, Si, S, Ta, K, K+, NH 4+, Na, Na+, elemental carbon, non-volatile nitrate and organic carbon. The PM2.5 annual average concentrations are found to increase from 2001 to 2003 (CAMS199). Though in none of the years the daily average concentrations exceeded the standard of 65mug/m 3, the annual averages are close to 15mug/m3. In addition, sulfate and organic carbon were found to be the major components of the total PM2.5 concentration. Receptor models, Principal Component Analysis and UNMIX, were used to identify and quantify the sources of PM 2.5. The speciated data from CAMS199, placed in an industrial location, gives six important sources contributed to total PM2.5. The six-source results showed that sulfate from industrial sources (44%), vehicles (19%), soil and dust (11%), vegetative burning (10%), sea spray (10%) and nitrate from multiple sources (6%) are the major contributors of the total ambient PM2.5. In addition, vegetative burning events are found to be distinct sources. UNMIX offered some advantages over PCA.