Measurements of OC and EC in coarse particulate matter in the southeastern United States
| Autor: | Rick D. Saylor, Traci L. Lersch, Eric S. Edgerton, John J. Jansen, Benjamin E. Hartsell, D. Alan Hansen, Gary S. Casuccio |
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| Rok vydání: | 2009 |
| Předmět: |
Total organic carbon
Detritus Carbon chemistry Environmental engineering chemistry.chemical_element Management Monitoring Policy and Law Particulates Biological materials Carbon Southeastern United States chemistry.chemical_compound chemistry Environmental chemistry Air Pollution Microscopy Electron Scanning Carbonate Pollen Particulate Matter Particle Size Elemental carbon Waste Management and Disposal Environmental Monitoring |
| Zdroj: | Journal of the AirWaste Management Association (1995). 59(1) |
| ISSN: | 1096-2247 |
| Popis: | The organic carbon (OC) and elemental carbon (EC) content of filter-based, 24-hr integrated particulate matter with aerodynamic diameters between 2.5 and 10 microm (PM10-2.5) was measured at two urban and two rural locations in the southeastern United States. On average, total carbon (OC + EC) comprised approximately 30% of PM10-2.5 mass at these four sites. Carbonate carbon was measured on a subset of samples from three sites and was found to be undetectable at a rural site in central Alabama, less than 2% of PM10-2.5 at an urban site in Georgia, and less than 10% of PM10-2.5 at an urban-industrial site in Alabama. Manual scanning electron microscopy (SEM) and computer-controlled SEM (CCSEM) along with energy dispersive X-ray spectroscopy (EDS) were used to identify individual carbonaceous particles in a selected subset of samples collected at one rural site and one urban-industrial site in Alabama. CCSEM results showed that biological material (e.g., fungal spores, pollen, and vegetative detritus) accounted for 60-70% of the carbonaceous mass in PM10-2.5 samples with concentrations in the range of 2-16 microg/m3. Samples with higher PM10-2.5 concentrations (25-42 microg/m3) at the urban-industrial site were found by manual SEM to have significant amounts of unidentified carbonaceous material, likely originating from local industrial activities. Both filter-based OC and EC concentrations and SEM-identified biological material tended to have higher concentrations during warmer months. Upper limits for organic mass (OM) to OC ratios (OM/OC) are estimated for PM10-2.5 samples at 2.1 for urban sites and 2.6-2.7 for rural sites. |
| Databáze: | OpenAIRE |
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