Aquatic ecosystem quality assessment of the Danube Delta in the periods April-October 2007 and 2008

Abstract

The present paper is focused on the quality assessment of surface water and sediment of the Danube Delta biosphere. Information is presented on water and sediment quality variations in organic/inorganic pollutants and heavy metals over a 2-years period (2007 and 2008) from April to October. Samples have been collected monthly from two different locations situated on St. George branch Murghiol and Uzlina, respectively. The analyses were performed by GC-ECD for orga-nochlorine insecticides and polychlorinated biphenyls (PCBs), GC-NPD for organophosphorus and triazine pesticides, HPLC-Fluorescence/UV for PAHs and phenylurea herbicides, IR for mineral oil, and AAS for metals. The monitoring results have shown, at both sampling points, a significant high organic load (BOD5, COD-Cr) of the water-bodies during all investigated periods, potentially threatening the river’s self-cleaning capacity. In sediment, an essential and dynamic part of the river basin, Cu was the predominant pollutant in all samples at levels (41-194 mg/kg dry weight) higher than the quality standard (40 mg/kg d.w.) according to the Romanian legislation (transposed from Directive 2000/60/EC).