Preliminary investigation of lower Danube pollution caused by potentially toxic metals

• Published in: Chemosphere (Oxford) Vol. 264; no. Pt 1; p. 128496
• Main Authors: Simionov, Ira-Adeline, Cristea, Dragos Sebastian, Petrea, Stefan-Mihai, Mogodan, Alina, Nicoara, Mircea, Plavan, Gabriel, Baltag, Emanuel Stefan, Jijie, Roxana, Strungaru, Stefan-Adrian
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.02.2021
• Subjects: Animals; Bioaccumulation; Biomonitoring; Black Sea; Cities; Danube; Environmental Monitoring; Geologic Sediments; Humans; Metals, Heavy - analysis; Metals, Heavy - toxicity; Rivers; Toxic metals; Water Pollutants, Chemical - analysis; Water Pollutants, Chemical - toxicity; Water quality; Black Sea; Cities; Biomonitoring; Danube; Bioaccumulation; Toxic metals; Water quality
• ISSN: 0045-6535; 1879-1298
• DOI: 10.1016/j.chemosphere.2020.128496

The current study aims to assess the pollution status of the European river-sea system lower Danube River-Danube Delta-North West Black Sea, through an integrated analysis of metal concentrations in water, sediments and fish community. The Danube flows through numerous industrial cities and receives a significant amount of pollutants due to the reception of urban and industrial emissaries, as well as agricultural land runoff. Samples of water, sediments and fish (10 species) were collected from 7 representative sites along Danube River, Danube Delta and Black Sea shore. For the analysed fish species, potentially toxic and essential elements (Pb, Cd, As, Cu, Fe, Zn, Mg, Ca, Na, K) from muscle and liver samples were measured and discussed. Measurement of elements and other environmental quality parameters were determined for water and sediments. The Black Sea area, represented by S6 and S7, received sediments from Danube with the lowest concentrations of Cd (0.05 ± 0.01 μg g−1, respectively 0.01 ± 0.001 μg g−1), Pb (3 ± 0.03 μg g−1, respectively 2 ± 0.03 μg g−1), As (2 ± 0.02 μg g−1, respectively 1.4 ± 0.3 μg g−1), Ni (8.9 ± 0.1 μg g−1, respectively 5.2 ± 0.2 μg g−1), Cr (8 ± 0.7 μg g−1, respectively 5 ± 0.2 μg g−1), Cu (3 ± 0.1 μg g−1, respectively 2 ± 0.04 μg g−1), Fe(6 ± 0.3 μg g−1, respectively 3 ± 0.1 μg g−1) and Zn (0.03 ± 0.003 μg g−1, respectively 0.017 ± 0.001 μg g−1). These results suggest that the Danube Delta system plays an important role in filtering the pollutants. Based on the biota and water analysis, there was no correlation observed between Cd, respectively Pb concentration in the environment and fish body (Person Coef. = −0.02 in muscle tissue and −0.01 in liver tissue, respectively Pearson Coeff. = −0.06 in muscle tissue and 0.1 in liver tissue). Cadmium remained an active element in the pollution of the Danube area (S1 and S2), with high concentration in the water matrix (0.14 ± 0.02 μg L−1, respectively 0.05 ± 0.01 μg L−1) and fish muscle (0.15 ± 0.03 μg g−1f.w. in C. carpio – S2). This fact was confirmed by several other studies. [Display omitted] •Toxic metal pollution status was investigated in this study through a multilevel analysis.•Cadmium is still present as a pollutant in the Lower Danube.•The Danube Delta was affected by metal pollution, based on past reports.•European industry located on the Danube has a lower impact with toxic metals.