Mercury in lake sediment cores of eastern and northern Canada

Recent and historical deposition of mercury (Hg) was examined over a broad geographic area from southwestern Northwest Territories to Labrador and from the U.S. Northeast to northern Ellesmere Island using dated sediment cores from 50 lakes (18 in midlatitudes (41-50N), 14 subarctic (51-64N) and 18 in the Arctic (65-83N)). Our objectives were to quantify latitudinal and longitudinal trends of anthropogenic Hg deposition in eastern and northern North America, to investigate variations in Hg deposition, to examine relationships with lake area, catchment/ lake area ratio and sedimentation rates, and to compare our results with model predictions.