Content of selected heavy metals in the organs of fish from Znin Duze Lake

Fish species constituting the majority of the fish population of Znin Daze Lake were selected for the investigations. They included: roach, white bream, common bream and perch. The largest amounts of detected metals accumulated in the liver and gills, and the lowest amounts occurred in muscle, except copper which had the lowest concentration in the gills. A bifactor analysis of variance revealed that the average concentrations of the elements in different organs differed significantly, but only in a few cases the average contents of mineral components in the same organ for different species differed significantly. The analysis of the dependence of the content of elements in different organs and the fish body length indicated a positive correlation for Cu, Fe and Ni, and a negative correlation for Zn and Mn in muscle. The analysis of the bioaccumulation coefficient revealed that the largest tendency to accumulate in muscle is displayed by zinc and iron, manganese and copper accumulate the least.