Polycyclic Aromatic Hydrocarbons in the Air in the St. Lawrence Basin (Québec)

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• 作者：Barnab&eacute ; Ngab&eacute ; and Laurier Poissant
• 刊名：Environmental Science & Technology
• 出版年：2003
• 出版时间：May 15, 2003
• 年：2003
• 卷：37
• 期：10
• 页码：2094 - 2099
• 全文大小：210K
• 年卷期：v.37,no.10(May 15, 2003)
• ISSN：1520-5851

文摘

High-volume air samples were collected from 1993 to1996 in rural areas of Québec to investigate on the levelsand the vapor-particle partitioning of polycyclic aromatichydrocarbons (PAHs). Ranges for the mean concentrationsof total PAHs (ng m^-3) were as follows: Villeroy, 3.31-18.92; St. Anicet, 7.57-22.84; and Mingan, 0.50-0.53. Lowermolecular weight PAHs predominated at all locations.Particle-gas partition coefficients (K_p) were in goodcorrelation with their vapor pressures (r ² = 0.79-0.97)with slopes deviating from the expected value of -1. Thecurve of the fractions of PAHs on particles in St. Anicetin 1995 fell on that of Lake Superior. In St. Anicet, fractionsof phenanthrene, fluoranthene, pyrene, and chrysene onparticles were close to those calculated from the soot-air partition coefficient (K_SA). At all sites the mean ratios ofparticulate PAH of the same molecular weight but ofvery different reactivities were similar during the samesampling days, suggesting that particle-bearing PAHs inVilleroy and Mingan were of the same nature as those foundin St. Anicet where adsorption onto soot particles wasthe major mechanism. Furthermore, the enthalpies ofdesorption for the predominant PAHs were close at allsites.