Satial and seasonal variations o heavy metals in water and sediment samles collected rom the Lower Danube River

Abstract

Surface water pollution with heavy metals represents one of the most relevant environmental issues, with severe outcomes on every other environmental compartment, affecting therefore the human health because of their toxicity, persistence and bioaccumulation tendency. The Danube, one of the most important rivers of Europe considering its course, crossing the continent from west to east, represents the main collector of all pollutants emitted by the ten countries it passes through, prior to discharging into the Black Sea. Given all this, and because of the possible unwanted effects that may occur as a result of recent constructions taking place in the area to improve the navigation conditions, the aim of this study is to evaluate the variation of the global concentration of heavy metals in both water and sediments by calculating the Metal Pollution Index (MPI) on the sector between Calarasi - Braila (km 370 - km 170). Water and sediment samples from Lower Danube were collected between January 2012 and December 2013, from ten different sites. The following heavy metals have been determined: chromium (Cr), copper (Cu), zinc (Zn), lead (Pb) and nickel (Ni). Metal Pollution Index values were used for a seasonal and spatial comparison of the total metal content from the established sites. For a more detailed interpretation of results, Cluster Analysis was performed. Frequent monitoring of the heavy metal content of Lower Danube has a significant impact on water quality, keeping a low pollution risk and having a long term positive impact on environmental protection of the Black Sea Basin.

Keywords

• Danube River
• heavy metals
• Metal Pollution Index
• Cluster Analysis