Vascular plants as sensitive indicators of lead and PCB transport from local sources in the Canadian Arctic

Vascular plants collected at background locations in the Canadian Arctic were assessed as biological indicators of the aerial transport of contaminants from nearby military radar sites. Significantly higher levels of lead and PCBs were found in plants from site background areas (collected up to 10 km from any known sources of contamination) than remote locations (collected at least 20 km away from any human activity) which indicates that these contaminants are being aerially redistributed from the sites to plants in surrounding background areas. An analysis of individual PCB congener signatures in plant site background samples using principal components analysis (PCA) revealed that the past use of specific commercial PCB formulations at these sites, such as Aroclor 1260 on the east coast, is reflected in the PCB congener signature present in the plants. The implications of these findings in terms of elucidating sources and the distribution of contaminants in the Canadian Arctic are discussed.