| Polycyclic Aromatic Hydrocarbons (PAHs) are ubiquitous pollutants in the environment. The distribution of atmospheric PAH between particulate and gas phases is determined through several factors, such as vapor pressure and octanol-air partition coefficients. Coniferous tree species have become one of the primary test objects due to their widespread distribution, utility, and reproducibility of the available experimental endpoints. The conifer needles may serve as passive biomonitors for airborne pollutants by reflecting the average contamination profiles in the air. Extraction of the wax layer from the inner needle fraction provides an indirect method of measuring the potentially bioavailable pollutant portions in the conifer needles. Samples were collected from several different sites to measure PAH concentrations. Their results were compared to determine if there were quantifiable differences in PAH concentration gradients between the contaminated and control sites. The results were also compared between years to verify continuity. The extractions were performed on a Dionex ASE200 Accelerated Solvent Extractor and cleaned afterwards by vacuum filtration using a Resprep 12-port manifold and activated basic alumina added to Normal Phase Resprep SPE Silica Gel Cartridges. Quantitation is performed by capillary gas chromatography/mass spectrometry (GC/MS) in selected ion monitoring mode (SIM). The gas chromatograph (HP-5890 Series II) is temperature-programmed and operated in splitless mode. Following quantitation and analysis, the data were tested for statistical significance. Findings show a significant difference between the contaminated and control sites for the first year but not for the second. The control site had a significant difference in PAH concentration between year one and year two. Also, no significance was found for an inverse relationship between PAH concentration and distance at the contaminated site for either year in the study. |
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