| Abstract [eng] |
The dissertation included the area that is poorly researched up to now: the patterns of the accumulation of heavy metals (HM) in fish body tissues determined by the metal interaction, exposing the different species of fish to multi-metal mixtures at maximum permissible HM concentrations (MPC) that are regulated of the EU for the inland waters. The results of this study showed that when exposing the fish to multi-metal mixtures with HM concentrations corresponding to MPC, the patterns of the HM accumulation in body tissues of the fish in most cases do not coincide with the patterns that are determined exposing the fish to the binary mixtures of HM. Therefore, the toxicity of the whole mixture, which is directly related to the interaction of metals, cannot be predicted (tested) by the toxic effects of single or several metals. The components of the mixture interact by quantitatively increasing or reducing each other's accumulation in the organisms. For this reason, the toxicity of the metals mixture can change and can be stronger or weaker than predicted. In addition, it has been determined that after 10-fold reduced concentration of a single metal in multi-metal mixture, the accumulation of some other metals in fish tissues can intensify. Correspondingly, decreasing in the concentration of a particular metal in the mixture does not necessarily result in a significantly lower accumulation of the metal in the fish tissues compared to the amount accumulated in the fish kept in the mixtures with a reduced concentration of any other HM. This shows that in the presence of other metals in the environment, the MPC that is determined for particular metal can be unsafe for the aquatic organisms. |
