Metal Pollution Assessment in Sediments of the Bulgarian Black Sea Coastal Zone
Valentina G. Doncheva ⃰, Ognyana D. Hristova, Boryana S. Dzhurova, Krasimira R. Slavova
Institute of Oceanology, Bulgarian Academy of Sciences, Departments "Marine chemistry", "Marine geology and archaeology", PO Box 152, Varna 9000, BULGARIA
*Corresponding author:
Abstract. The present study was conducted to assess the pollution status of the coastal sediments of the Bulgarian Black Sea coastal zone using sediment pollution indices. Eleven sites and twenty-two stations from monitoring grid were selected for the collection of samples. The heavy metal concentrations were used to calculate: geoaccumulation index (Igeo); enrichment factor (EF); contamination factor (CF); modified degree of contamination (mCd); pollution loading index (PLI). In addition, ecotoxicological level of trace metals in sediments was also assessed by comparing with the numerical sediment quality guidelines (SQGs). Mean ERM quotient (mERM–Q) and mean PEL (m-PEL–Q) were applied for assessing the potential effects of multiple heavy metal contamination in sediments. The pollution level assessed by indices related to background level of the studied sites ranged from unpolluted to moderate and only in one case considerably polluted due to heavy metals, mainly Pb and Zn. Ecotoxicological risk was assessed as low and moderately low due to the presence of Pb, Cu, Ni. The northern Danube influenced area of the Bulgarian coastal zone was categorized according to the applied indices as slightly polluted with Zn and Pb. The sediments from the "hot spot" points were with higher accumulation of Ni, Cu and Pb.
Key words: Black Sea, metal pollution, coastal sediments, sediment quality indices, sediment quality guidelines.

Ecologia Balkanica, 2020, Volume 12, Issue 1 pp. 179-189
Article № eb.20102 [Full text - PDF]pdf

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