Heavy metal contents in water, sediment and fish in a karst aquatic ecosystem of the Plitvice Lakes National Park (Croatia).

An evaluation of the quality status of the pristine karst, tufa depositing aquatic environment of the Plitvice Lakes National Park based on the analysis of heavy (ecotoxic) metals was examined for the first time. Analyses of trace metals in water, sediment and fish (Salmo trutta, Oncorhynchus mykiss, Squalius cephalus) samples were conducted either by stripping voltammetry (Zn, Cd, Pb and Cu) or cold vapour atomic absorption spectrometry (Hg). The concentration of dissolved trace metals in water was very low revealing a pristine aquatic environment (averages were, in ng/L: 258 (Zn), 10.