In the first multi-year arctic air sampling program, PAHs were sampled (vapor and particulate) every week at three locations in the Canadian and Russian Arctic. Data are presented here for the years 1992−1994. The geometric mean ∑PAH concentrations (where ∑ = 16 compounds) for 1993 ranged from 249 to 508 pg/m3 for the three sites. Clear seasonality was evident with the highest concentrations oc curring during the colder months of October−April, coinciding with the arctic haze period. PAH concentrations during this period were highest in the order of Dunai (Russian) > Alert (high Arctic) > Tagish (Pacific). Air mass back trajectories computed for February 1994 revealed long-range transport from Eurasia into the high Arctic. Short periods of high concentrations were also evident during the warmer months, most notably at the Tagish site, where elevated levels of retene (a marker for soft wood combustion) matched forest fire records. Initial findings suggest that the gas/particle partitioning of some of the lighter PAHs, examined during the colder haze period, is similar to remote temperate studies and in reasonable agreement to the Junge−Pankow adsorption model.

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In 1992, a long term program was established to measure the airborne concentrations of persistent organic pollutants (POPs) in the Arctic. To maximize spatial variation over a wide geographical area, three Arctic locations were selected; two sites in Canada, Alert on Ellesmere Island and Tagish in the western Yukon, and one in Russia at Dunai Island in eastern Siberia. PCB data is presented here for the years 1992-1994. Mean ∑PCB concentrations for 1993, the year when all three sites were running simultaneously, were 27.4, 17.0, and 34.0 pg/m 3 at the Alert, Tagish, and Dunai sites, respectively. With the exception of the Tagish site in 1993, where ∑PCB concentrations were found to be weakly correlated with mean monthly temperatures, no correlation with temperature was observed. However, changes in the homolog group profile with temperature were apparent. On an annual basis, the trichlorinated congeners made the largest single contribution to the atmospheric concentrations of ∑PCB, however, this contribution declined with the onset of warmer months. This temperature-dependent homolog pattern was most clearly evident at Dunai, where the contribution of the pentachlorinated congeners matched or exceeded that of the trichlorinated congeners during May, June, and July of 1993. It was also evident at Alert and Tagish, but not to the same degree. Spatial and year-to-year differences at these Arctic sites were attributed to both the site's proximity to source areas (where different PCB mixtures and quantities have been used) and to the influence of air mass movement from these source regions.

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