Concentration of Cd (II), Cu (II), Pb (II), Se (IV) and Zn (II) in cultured sea bass (Dicentrarchus labrax) tissues from Tyrrhenian Sea and Sicilian Sea by derivative stripping potentiometry

The purpose of this study is to investigate the bioaccumulation of trace metals (Zn, Cu, Se, Cd, and Pb) in cultured Dicentrarchus labrax tissues, liver and muscle, from the Sicilian coasts of Mediterranean sea. The relationship between heavy metals contamination of feed and seawater and their bioaccumulation in fish tissues was also studied. Potentiometric stripping analysis (PSA) was used to determine simultaneously the content of Cd (II), Cu (II), Pb (II) and Zn (II), in fish tissues, feed and sea water, whereas selenium concentration was determined by cathodic stripping potentiometry (CSP). Metal cations were extracted from fish tissues, commercial feed and sea water (for total metal determination) by peroxide hydrogen/hydrochloric acid treatments; seawater did not need any sample pre-treatment for dissolved metals determination. The low concentration of metals in the studied matrices required a highly sensitive method for their determination and a simple sample preparation procedure, and the proposed method was well-suited for this purpose.