Heavy metals in Chukchi Sea sediments as compared to selected circum-arctic shelves

Abstract

Surficial sediments from 31 stations on the northeastern Chukchi Sea, Alaskan Arctic were analysed by AAS and ICP-AES for Si, Al, Fe, Mn, Cu, Cr, Co, Zn, Ni and V. The metal concentrations are related to the sediment granulometry and show no correlations with organic carbon. Presumably all the heavy metals, except Cr and Co, are either adsorbed on clays and/or coprecipitated with ferrimanganic hydroxide. Cobalt is partitioned in an unknown mineral phase within the sand fraction.Comparison of the heavy metal concentrations in muds of the Chukchi Sea with those of the high arctic shelves of Russia, East Greenland and the Beaufort Sea shows relatively lower levels of most metals in the Chukchi. Presumably these disparities are related to regional differences in sediment chemistries inherited from natural terrigenous sources rather than to any enhanced pollution in the non-Chukchi areas.It is suggested that the concentrations and accumulation rates of the heavy metals reported here can serve as reliable baselines to monitor metal pollution in the Chukchi Sea.