Polychlorinated Biphenyls in Arctic Air. 1. Temporal and Spatial Trends: 1992-1994
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- 作者：G. A. Stern ; C. J. Halsall ; L. A. Barrie ; D. C. G. Muir ; P. Fellin ; B. Rosenberg ; F. Ya. Rovinsky ; E. Ya. Kononov ; and B. Pastuhov
- 刊名：Environmental Science & Technology
- 出版年：1997
- 出版时间：December 1997
- 年：1997
- 卷：31
- 期：12
- 页码：3619 - 3628
- 全文大小：338K
- 年卷期：v.31,no.12(December 1997)
- ISSN：1520-5851
文摘
In 1992, a long term program was established to measurethe airborne concentrations of persistent organicpollutants (POPs) in the Arctic. To maximize spatialvariationover a wide geographical area, three Arctic locations wereselected; two sites in Canada, Alert on Ellesmere Islandand Tagish in the western Yukon, and one in Russia atDunaiIsland in eastern Siberia. PCB data is presented herefor the years 1992-1994. Mean 
PCB concentrationsfor1993, the year when all three sites were runningsimultaneously, were 27.4, 17.0, and 34.0 pg/m3 at theAlert,Tagish, and Dunai sites, respectively. With theexceptionof the Tagish site in 1993, where PCB concentrationswere found to be weakly correlated with mean monthly temperatures, no correlation with temperature was observed.However, changes in the homolog group profile withtemperature were apparent. On an annual basis, thetrichlorinated congeners made the largest single contributionto the atmospheric concentrations of PCB, however, thiscontribution declined with the onset of warmer months.This temperature-dependent homolog pattern was mostclearlyevident at Dunai, where the contribution of the pentachlorinated congeners matched or exceeded that of thetrichlorinated congeners during May, June, and July of1993. It was also evident at Alert and Tagish, but not tothesame degree. Spatial and year-to-year differences atthese Arctic sites were attributed to both the site'sproximityto source areas (where different PCB mixtures andquantitieshave been used) and to the influence of air massmovement from these source regions.
PCB concentrationsfor1993, the year when all three sites were runningsimultaneously, were 27.4, 17.0, and 34.0 pg/m3 at theAlert,Tagish, and Dunai sites, respectively. With theexceptionof the Tagish site in 1993, where PCB concentrationswere found to be weakly correlated with mean monthly temperatures, no correlation with temperature was observed.However, changes in the homolog group profile withtemperature were apparent. On an annual basis, thetrichlorinated congeners made the largest single contributionto the atmospheric concentrations of PCB, however, thiscontribution declined with the onset of warmer months.This temperature-dependent homolog pattern was mostclearlyevident at Dunai, where the contribution of the pentachlorinated congeners matched or exceeded that of thetrichlorinated congeners during May, June, and July of1993. It was also evident at Alert and Tagish, but not tothesame degree. Spatial and year-to-year differences atthese Arctic sites were attributed to both the site'sproximityto source areas (where different PCB mixtures andquantitieshave been used) and to the influence of air massmovement from these source regions.