OBJECTIVES: This study determines the levels of selected contaminants in the muscle of three common fish species from the upper course of the Nitra River. DESIGN: Were detected levels of Zn, Cu, Ni, Cr, Pb, Cd and Hg in the muscle and correlations among selected metals as well as standard length and total weight in brown trout (Salmo trutta morpha fario), Alpine bullhead (Cottus poecilopus) and grayling (Thymallus thymallus). RESULTS: The content of analysed metals (mg.kg-1 wet weight) ranged as follows: brown trout - Zn 5.86-12.97, Cu 0.51-0.76, Ni 0.00-0.37, Cr 0.18-0.41, Pb 0.00-0.34, Cd 0.03-0.13, Hg 0.04-0.07; Alpine bullhead - Zn 7.02-13.68, Cu 0.34-0.62, Ni 0.00-1.13, Cr 0.19-0.24, Pb 0.00-0.37, Cd 0.03-0.09, Hg 0.06-0.18; grayling - Zn 3.38-6.36, Cu - 0.46-0.62, Ni 0.04-0.22, Cr 0.13-0.22, Pb 0.00-0.25, Cd 0.02-0.09, Hg 0.05-0.12, respectively. CONCLUSIONS: The Slovak permissible limits for safe consumption, defined in the Commission Regulations No. 1881/2006 and 629/2008, in the case of Pb, Cd and Hg were exceeded in 10%, 63% and 0%, respectively.

Department of Poultry Science and Small Farm Animals Faculty of Agrobiology and Food Resources Slovak University of Agriculture Nitra Slovakia

University of South Bohemia in Ceske Budejovice Faculty of Fisheries and Protection of Waters South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses Institute of Aquaculture and Protection of waters Ces Czech Republic