Whole-lake lead burdens in sediments of lakes in southern Ontario, Canada

Abstract

The anthropogenic stable lead content of the sediments of eight softwater Precambrian lakes in southern Ontario was measured at 34–92 sites per lake. Whole-lake anthropogenic lead burdens varied between only 610 and 770 mg m-2. There was no relationship between lead burden and either water replenishment time of the lake (Tw) or the ratio of watershed area to lake area (Ad/A0), which varied by factors of 4 and 12 respectively. These results can be explained if a) the lead deposition in this region is uniform, and b) the only significant input of lead to the lakes is via deposition from the atmosphere directly on the lakes’surfaces. Therefore spatial differences in anthropogenic lead within a lake represent the redistribution or focusing pattern of the sediments.