| Abstract
| - Concentrations of gas-phase polychlorobiphenyls (PCBs)were studied over an austral summer at a site in Terra NovaBay, Antarctica. Gas-phase concentrations of individualPCB congeners in the atmosphere of Terra Nova Bay rangedfrom below the detection limit to 0.25 pg m-3, with amean concentration of ∑PCB of 1.06 pg m-3. The PCBprofile was dominated by lower-chlorinated PCB congeners;in fact >78% of the total PCB content was due tocongeners with 1−4 chlorine atoms and only about 10%with 5−7 chlorines, whereas higher-chlorinated PCBcongeners were below detection limits. The mean ∑PCBconcentration obtained in this study were lower than thosereported in previous Antarctic studies. Temporal concentration profiles of ∑PCB do not correspond to seasonaltemperature changes. In consideration of the low PCBconcentrations observed, the studies with the wind roses,the regression between ln P(PCB) and T-1, and thedistribution of congeners, we can hypothesize that PCBlocal source contributions are not very important, whereaslong-distance transport is the prevalent factor bringingPCBs to Terra Nova Bay.
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