Assessment of metallic element contaminants in sediment of four Tunisian fish farms (Eastern Mediterranean) (Article 3)

Concentration of selected Metallic Element Contaminants (MECs) (Cd, Pb, Cu, Fe, Zn, Mn, Mg, Ca, Na and K), Total Organic Carbon (TOC) and Total Nitrogen (TN) in the superficial layer of sediments from four fish farms in the Eastern Mediterranean Sea were studied in order to evaluate the environmental effects of marine aquaculture and to establish correlations between aquaculture and accumulation of MECs. The concentrations of Cd, Pb and Cu were determined by atomic absorption spectrophotometry with graphite furnace and Zeeman correction (Varian 220 Z). The Metallic Element Fe, Zn, Mg, Mn, K, Na and Ca were measured by the flame atomic absorption spectrophotometry (Varian AA 10). The results suggested that MECs enrichment in the sediments may be attributed to the fish farm effluents, although metal concentrations are not likely to cause harmful effects in the marine ecosystem. Continuous monitoring and further studies of the area are recommended to determine long-term effects.