Long-term nutrients and heavy metals concentration dynamics in aquatic ecosystems of Danube Delta

This study aims to make an overview of the last fifteen years of contamination freshwater, in the Danube river, branches and delta lakes. The water quality of the river and Delta lakes was described by analysing the data for nutrients and some heavy metals. The concentrations elements (n, Cd, Cu, Pb) in the water are compared with heavy metals in fish, captured in natural delta lakes. Bioconcentration factor (BCF) is described in some commercial fish species.