Heavy metals in the sediments of an arctic lagoon, northern Alaska

Abstract

The total abundances of V, Cr, Mn, Fe, Co, Ni, Cu, and Zn in oxic, nearshore sediments of north arctic Alaska, are similar to those of corresponding pristine or pre-industrial-age sediments of many tropical-temperate regions, and thus do not reflect the unique weathering and depositional processes of the Arctic. Laboratory experiments on metal partitioning suggest that about 50% of the metal contents (<20% for V, Cr), which are bound predominantly in Fe oxides, may be mobilized into solution following the onset of reducing conditions at the sediment surface. A three-part extraction design would be effective in discriminating the three major associations of heavy metals in the sediments: easily leachable, Fe hydroxides, and refractory particles, and is recommended for use in monitoring the nearshore Beaufort Sea for future contamination by heavy metals.