THE GENOTOXIC IMPACT TO PERIPHERAL BLOOD CELLS OF PERCA FLUVIATILIS INDUCED BY MULTIPLE STRESSORS. COMET ASSAY AND NUCLEAR ABNORMALITIES ANALYSIS

Anthropogenic pollution in aquatic systems is damaging living organisms. Furthermore, aquatic animals are constantly exposed to naturally occurring parasitic infections, which may infringe host (i. e. fish) immune system weakening its resistance to various pollutants such as metals. Consequently, this study focuses on genotoxic damage to Perca fluviatilis peripheral blood cells induced by naturally occurring stressors (co-infection with Trichodina sp. and Saprolegnia parasitica) and anthropogenically caused ones (heavy metals). These stressors occurring simultaneously lead to unpredictable genotoxic outcomes in aquatic organisms. Until now, there have been no studies focusing on combined effects of parasitic co-infection and metal mixture exposure, only on genotoxic effects caused by single stressor. Therefore, in this study the analysis of nuclear abnormalities, such as micronucleus (MN), nuclear buds (NB), blebbed nuclei (BL) and comet assay analysis in erythrocytes of peripheral blood cells was performed. The experimental study was designed to recreate realistic interaction conditions concerning multiple stress effects to show possible genotoxicity outcomes. Results indicate that simultaneously co-infected and exposed to pollutants fish tend to get highest genotoxic impact compared to when only one stressor is present. The study also suggests that stressors may affect fish in synergetic manner, strengthening one another's genotoxic impact.