OBJECTIVES: Atrazine and its chloro-s-triazine metabolites are found in surface water and groundwater of the Czech Republic, although their use has been banned since 2005. The objective of the study was to determine the toxic effects of atrazine at an environmentally relevant concentration of atrazine, 0.3 μg.L-1 and at concentrations of 30, 100, and 300 μg.L-1 on morphometric and condition characteristics, development of early life stages, and antioxidant defense enzymes of common carp. METHODS: The embryo-larval toxicity test was performed according to the OECD Guidelines 210 (Fish, Early-life Stage Toxicity Test). RESULTS: Atrazine exposure showed no effect on morphometric and condition characteristics or histology. Exposure at 0.3 μg.L-1 was associated with significantly increased activity of glutathione peroxidase, glutathione S-transferase, superoxide dismutase, and catalase compared to control. Activity of glutathione reductase was slightly higher at a concentration of 0.3 μg.L-1, with significantly lower (p<0.05) activity observed in groups exposed to 30, 100, and 300 μg.L-1 compared to the group exposed to 0.3 μg.L-1. The level of oxidized lipids was slightly higher in groups exposed to atrazine at 100 and 300 μg.L-1 compared to controls. CONCLUSIONS: Atrazine has a significant influence on the biotransformation enzyme and oxidative defense enzymes of early life stages of common carp. The lowest observed effect concentration (LOEC) was 0.3 μg.L-1.

Institute of Vertebrate Biology Academy of Sciences of the Czech Republic Brno Czech Republic

University of Veterinary and Pharmaceutical Sciences Brno Czech Republic