Ponds serving as passive additional treatment mediators for treated wastewater are used in aquaculture of cyprinids. We investigated how the metabolism of carp originating in clean water can adapt to water containing many residual pollutants, including pharmaceuticals, which are not completely removed at the wastewater treatment plant. In addition, we observed the activation of enzyme defense mechanisms during oxidative stress in the fish body. We also wanted to investigate the time needed for fish to get rid of undesirable metabolites, including drug residues, if they are cultured from early stages in treated wastewater and then restocked into clean water.
In the liver of carp kept in treated wastewater, we recorded a high number of various metabolites, which did not occur in fish originating from clean water. The transfer of fish from clean to treated wastewater caused immediately high oxidative stress. Seven days after the fish restocking, we measured the concentrations of drugs in the carp liver comparable to fish living in the treated wastewater throughout the year. After fish restocking from the treated wastewater to the clean water, fish were able to get rid of most of the monitored drugs within 14 days, but metabolic changes in the liver and antioxidant response in other tissues remained significantly increased for 2-6 months. This study contributed to elucidating the potential of treated wastewater use for aquaculture in biological ponds.
Detailed information can be found in the original article: Koubová, A., Van Nguyen, T., Grabicová, K., Burkina, V., Aydin, F.G., Grabic, R., Nováková, P., Švecová, H., Lepič, P., Fedorova, G., Randák, T., Žlábek, V., 2022. Metabolome adaptation and oxidative stress response of common carp (Cyprinus carpio) to altered water pollution levels. Environmental Pollution 303, 119117. https://doi.org/10.1016/j.envpol.2022.119117
The alterations in the water pollution levels affect the metabolic profiles of restocked fish.
Written by: RNDr. Anna Koubová, Ph.D.