Heavy Metal Enrichment of Man-made Origin of Superficial Sediment on the Continental Shelf of the North-western Black Sea

Statistical techniques were used to chemically identify ‘ abnormal ’ sediments, either contaminated by or naturally enriched in heavy metals. Iron was used for normalization. After assessing the possible contribution of natural enrichment processes, relative enrichments of man-made origin ranging from 50% to more than 200% were estimated for Co, Ba, Cu, Pb, Zn and Cd, usually, contamination drastically decreases with depth in the sedimentary column. The shelf areas most affected by heavy metal pollution are the Danube delta front, Danube prodelta and the central zone of the sediment-starved continental shelf. Romanian and Ukrainian oil-drilling activities heavily affect Ba concentrations in sediments and also contribute to the pollution of the continental shelf by other heavy metals.