The inventories of anthropogenic Ph, Zn, As, Cd, and the radionuclides 137Cs and excess 210Pb in lake sediments of the Adirondack region, USA

Abstract

We determined the inventories of four anthropogenic trace elements, Pb, Zn, As, and Cd, and two radionuclides, 137Cs and excess 210Pb, in sediment cores collected from eight remote lakes in the Adirondack region of the northeastern United States. The inventories of all six substances vary considerably among the sediment cores, although the lakes and their associated catchments must have received similar cumulative per unit area atmospheric inputs of these substances. These variations are highly correlated, indicating that the trace elements and radionuclides are affected in a coherent way by the processes controlling their deposition to the sediments of these lakes. Assuming that the anthropogenic trace element inventories in each sediment core are enhanced or depleted relative to cumulative atmospheric deposition to the extent indicated by the sediment core inventories of either 137Cs or excess 210Pb, we produced estimates of the cumulative atmospheric inputs of the four anthropogenic trace elements to this region. Comparison of the excess 210Pb normalized anthropogenic Pb, Zn, Cd inventories of the Adirondack sediment cores with excess 210Pb normalized inventories of the same substances in a group of South Central Ontario lakes suggests that the Adirondack region has received greater cumulative anthropogenic inputs of Pb, Zn and Cd by a factor of 1.6, 4.5, and 2.9, respectively.