Heavy metals in sediment, water and cultivated common carp (Cyprinus carpio L.) in Croatian waters

Variations in the elemental composition of different carp (Cyprinus corpio) organs (liver, kidney, eggs, intestine, spleen and skin + muscle) from three Croatian fish farms were investigated. Sediments and water samples were also taken from each pond. All measurements were carried out by the source excited Energy Dispersive X-Ray Fluorescence method (EDXRF). Significant difference was found in the sediment and water composition among the three fish farms (p < 0.01). Compared to fish farm 1, concentrations of heavy metals in sediments and water from fish farm 2 were between 2 and 6 times higher and from fish farm 3 between 2 and 5 times higher. The following concentrations ranges (expressed as wet weight) were measured in different carp organs: Pb (0.11-1.45 mg/kg); Cr (0.10-3.72 mg/kg); Mn (1.70-28.47 mg/kg); Fe (8.09-117.21 mg/kg); Cu (0.41-4.09 mg/kg) and Zn (4.61-171.53 mg/kg). Significant difference was found in selected heavy metal concentrations of selected organs at each location as well as among the three locations (p < 0.05). Generally, carp from fish farm 2 had the highest concentration of the majority of elements (Pb, Cr, Mn, Fe Cu, Zn), while carp from fish farm I had the lowest concentration, demonstrating an impact of the geochemical environment on heavy metal concentrations in carps.