Comparison of Lichen, Conifer Needles, Passive Air Sampling Devices, and Snowpack as Passive Sampling Media to Measure Semi-Volatile Organic Compounds in Remote Atmospheres

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• 作者：Jill E. Schrlau ; Linda Geiser ; Kimberly J. Hageman ; Dixon H. Landers ; Staci Massey Simonich
• 刊名：Environmental Science & Technology
• 出版年：2011
• 出版时间：December 15, 2011
• 年：2011
• 卷：45
• 期：24
• 页码：10354-10361
• 全文大小：1028K
• 年卷期：v.45,no.24(December 15, 2011)
• ISSN：1520-5851

文摘

A wide range of semivolatile organic compounds (SOCs), including pesticides and polycyclic aromatic hydrocarbons (PAHs), were measured in lichen, conifer needles, snowpack and XAD-based passive air sampling devices (PASDs) collected from 19 different U.S. national parks in order to compare the magnitude and mechanism of SOC accumulation in the different passive sampling media. Lichen accumulated the highest SOC concentrations, in part because of its long (and unknown) exposure period, whereas PASDs accumulated the lowest concentrations. However, only the PASD SOC concentrations can be used to calculate an average atmospheric gas-phase SOC concentration because the sampling rates are known and the media is uniform. Only the lichen and snowpack SOC accumulation profiles were statistically significantly correlated (r = 0.552, p-value <0.0001) because they both accumulate SOCs present in the atmospheric particle-phase. This suggests that needles and PASDs represent a different composition of the atmosphere than lichen and snowpack and that the interpretation of atmospheric SOC composition is dependent on the type of passive sampling media used. All four passive sampling media preferentially accumulated SOCs with relatively low air鈥搘ater partition coefficients, while snowpack accumulated SOCs with higher log K_OA values compared to the other media. Lichen accumulated more SOCs with log K_OA > 10 relative to needles and showed a greater accumulation of particle-phase PAHs.