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Possibilities of using the multigenerational test on the organism Daphnia magna
Měšťánková, Anna ; Maršálková, Eliška (referee) ; Zlámalová Gargošová, Helena (advisor)
This bachelor thesis focuses on the study of the effects of pharmaceutical substances ibuprofen, ketoprofen, and acetylsalicylic acid, as well as their combinations, on the freshwater organism Daphnia magna through multigenerational ecotoxicological tests. The presence of pharmaceutical residues in ecosystems is a significant environmental problem, which necessitates a deeper understanding of their long-term effects on organisms, including aquatic ones. The work monitored the influence of the aforementioned pharmaceuticals through acute tests, as well as chronic ones. While the acute toxicity of these substances is not significant, their long-term impact was demonstrated through chronic tests. A significant decrease in the reproductive capacity of D. magna was observed, manifesting not only in the delay of the first brood but primarily in the overall decrease in offspring numbers across generations. The findings indicate that the combination of drugs can have synergistic toxic effects, which in some cases may lead to a complete cessation of reproduction. Additionally, growth inhibitions, behavioral changes, and body deformations in exposed organisms were observed. These multigenerational tests provide a comprehensive and realistic view of the potential ecotoxicological risk of pharmaceuticals in freshwater ecosystems and support the need for in-depth research on the impact of pharmaceuticals on aquatic organisms.
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Use of the organism Daphnia magna in a multigenerational ecotoxicity test
Klasová, Kristýna ; Maršálková, Eliška (referee) ; Zlámalová Gargošová, Helena (advisor)
This bachelor thesis deals with the multigenerational effect of microparticles of the biodegradable polymer polyhydroxybutyrate (P3HB) on the freshwater organism Daphnia magna. The presence of microplastics in the environment is a frequently discussed environmental problem, hence efforts are being made to develop biodegradable plastics that would degrade more easily in the environment. The most studied biopolymer P3HB, however, there is not much information on its ecotoxicity yet. In the context of this work, ecotoxicity was assessed using a multigeneration assay; in addition, the effect of P3HB microparticles was compared to that of naturally occurring particles. Multigeneration assays are not yet commonly used for ecotoxicological evaluation, but they offer a comprehensive and realistic view of the effect of the test substance on the test organisms. In this work, 4 generations of D. magna were exposed to P3HB microparticles and kaolin microparticles for comparison. The results showed no negative effect on the mortality of the organism, but a slight decrease in reproductive activity was observed.
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