Heavy metal pollution of some Danube Delta lacustrine sediments studied by neutron activation analysis

Using neutron activation analysis and radiometric measurements, the vertical distribution of six possible pollutant elements (Zn, Cr, Co, As, Sb and Br), two trace elements of natural origin (Sc and Hf) and radioactive 137Cs were determined in three lakes, Furtuna, Lung and Mesteru, located in an active sedimentary zone of the Danube Delta. The accumulation rate of recent sediments was estimated from radiocesium profiles. Zn, As, Sb and Br were identified as possible pollutants. The vertical profiles of their concentrations reflect recent historic inputs, showing a gradual increase until around 1990, followed by a continuous decrease.