Molecular composition of organic fine particulate matter in Houston, TX

Organic fine particulate matter collected in Houston, TX between March 1997 and March 1998 was analyzed to determine the concentration of individual organic compounds. Samples from four sites were analyzed including two industrial locations (Houston Regional Monitoring Corporation (HRM-3) site in Channelview and Clinton Drive site near the Ship Channel Turning Basin), one suburban location (Bingle Drive site in Northwest Houston) and one background site (Galveston Island). At the three urban locations, samples were divided into three seasonal sample aggregates (spring, summer and winter), while at the background site a single annual average sample pool was used. Between 10 and 16 individual samples were pooled to get aggregate samples with enough organic carbon mass for analysis. Overall, 82 individual organic compounds were quantified. These include molecular markers which are compounds unique to specific fine particle sources and can be used to track the relative contribution of source emissions to ambient fine particle levels. The differences both spatially and temporally in these tracers can be used to evaluate the variability in emission source strengths.