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Utilization of organism Daphnia magna in ecotoxicity tests
Winklerová, Lucie ; Vávrová, Milada (referee) ; Zlámalová Gargošová, Helena (advisor)
This thesis deals with ecotoxicity tests of selected substances used in agriculture and horticulture. It is focused on the determination of acute and chronic toxicity of selected herbicides. These herbicides are sold commercially, specifically Finalsan (active substance is nonanoic acid), the product of Neudorff GmbH KG company, and Dominator (active substance is glyphosate, isopropylamine salt) by Dow AgroSciences Ltd. Next tested substances are potassium nitrate and sodium nitrate - common agricultural fertilizers. Potassium dichromate was also tested. Potassium dichromate is very toxic for aquatic environment and it is used as the standard in acute tests. Tests were carried out in terms of effects on aquatic systems, due to very good solubility in water of selected substances. The tests were performed on the organism Daphnia magna.
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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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Fotoiniciovaná degradace vybraných léčiv (dexametazonu, prednisolonu, fluoxetinu) a testování toxicity léčiv a produktů jejich fotodegradace na vodní organismy (\kur{Daphnia magna})
DOKOUPILOVÁ, Eliška
This diploma thesis investigates kinetics of photoinitiated degradation of selected drugs (dexamethasone, prednisolone, fluoxetine) under conditions relevant to surface waters and provides results of toxicity tests of original compounds and their photodegradation products mixtures for a representant of aquatic organisms, cladoceran Daphnia magna. The theoretical part describes the basic characteristics, mechanism of action and therapeutic usage of selected drugs. Toxicological studies related to adverse effects of these substances on aquatic organisms are also briefly outlined. The experimental part presents first the results of photochemical degradation kinetics of the studied compounds and second the findings of chronic toxicity tests of the selected drugs and their photoproducts mixtures on Daphnia magna, namely on the number of juveniles, on the number of clutches and on the body size.
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Toxicity of nanomaterials to aquatic crustaceans
Novotná, Kateřina ; Kočí, Vladimír (advisor) ; Cajthaml, Tomáš (referee)
Nowadays, nanomaterials are broadly used for many purposes thanks to their unique properties. The production of nanoscale materials is growing rapidly. Consequently, it means a high probability of their release into the environment and there are concerns about their possible negative effects on organisms. Furthermore, the behaviour of nanomaterials might be strongly influenced by many factors and there are many different types of them, so there is still a big information gap in this field. The aim of this work is to summarize basic facts about nanomaterials and their possible toxicity, especially to the fresh-water crustacean Daphnia magna. An impact of nanoscale zero-valent iron particles is tested on this species. This material is used for remediation so it is injected directly into the environment. Concentrations of 0,1 g·l-1 , 0,5 g·l-1 , 1 g·l-1 and 2,5 g·l-1 of two products with different surface modifications were tested. It was found that the toxicity depends on the type of stabilization. EC50 was not established for NANOFER 25S (with a special surface modification) due to the maximum immobilization rate of only 30 % for the concentrations tested. However, the EC50 value for NANOFER 25 (without the special surface modification) is 0,94 g·l-1 . These results confirm that it is necessary to...
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Testy toxicity s perloočkou Daphnia magna
Melezínková, Petra
The aim of this thesis was to derermine the values of toxic effect of chemical sub-stance chemical on the tested organism Daphnia magna. For testing, these materials were selected: polyaluminiumchloride (PAX 18), its aqueous solution (PAX 19) and potassium dichromate. The thesis is divided into two parts, in the first half I devote to theory of the basic terminology of the issue and the general characterization of the tested organism. In the practical part I focus on the characteristics of the used substances, the course of the tes-ting and the results of the work together with the discussion. Experimental concentrations for PAX 18 were between 1-100 mg.l-1, for PAX 19 10-300 mg.l-1 and for potassium dichromate 40-150 mg.l-1. Testing was perfomed in 3 repeatings with ten individuals + control. 24hEC50 values were: for PAX 18 45,06 mg.l-1, for PAX 19 97,82 mg.l-1 and for potassium dichromate 1,569 mg.l-1. The values of 48hEC50 for PAX 18 byly 22,62 mg.l-1, for PAX 19 37,20 mg.l-1 and for potassium dichromate 0,864 mg.l-1. In all tests, fluctuations in pH and dissolved oxygen content, as well as the number of inhibited individuals, were observed. The results of the observations were plotted and then commented verbally.
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Štandardizácia chovu Daphnia magna pre testy toxicity
Kučera, Štefan
The diploma thesis is primarily focused on the standardization of Daphnia magna breeding in laboratory conditions of the Department of Zoology, Fisheries, Hydrobiology and Beekeeping at the Faculty of Agronomy of the Mendel University in Brno. The main aim of the work is to simplify the preparation of medium for breeding Daphnia magna due to time saving. During testing, we were interested in births and mortality of individuals observed during 14-day tests in two media. We focus on chemical and physical properties of the media, namely the pH, temperature and intensity of the light.
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Toxicita vybraných antiarytmik (verapamilu a diltiazemu) pro vodní organismy \kur{(Dpahnia magna)}
DOKOUPILOVÁ, Eliška
This bachelor thesis deals with a group of antiarrhythmic drugs and their toxicity to aquatic organisms. The theoretical part of the thesis summarizes the basic characteristics and distribution of antiarrhythmics, their mechanism of action and therapeutic use in the treatment of cardiovascular diseases together with their occurrence in the aquatic environment. Toxicology testing and related adverse effects of drugs on aquatic organisms are also described. The experimental part presents the results from a 21 day chronic toxicity test of verapamil and its degradation products on number of juveniles, number of broods and the body size of cladoceran Daphnia magna.
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Toxicity of nanomaterials to aquatic crustaceans
Novotná, Kateřina ; Kočí, Vladimír (advisor) ; Cajthaml, Tomáš (referee)
Nowadays, nanomaterials are broadly used for many purposes thanks to their unique properties. The production of nanoscale materials is growing rapidly. Consequently, it means a high probability of their release into the environment and there are concerns about their possible negative effects on organisms. Furthermore, the behaviour of nanomaterials might be strongly influenced by many factors and there are many different types of them, so there is still a big information gap in this field. The aim of this work is to summarize basic facts about nanomaterials and their possible toxicity, especially to the fresh-water crustacean Daphnia magna. An impact of nanoscale zero-valent iron particles is tested on this species. This material is used for remediation so it is injected directly into the environment. Concentrations of 0,1 g·l-1 , 0,5 g·l-1 , 1 g·l-1 and 2,5 g·l-1 of two products with different surface modifications were tested. It was found that the toxicity depends on the type of stabilization. EC50 was not established for NANOFER 25S (with a special surface modification) due to the maximum immobilization rate of only 30 % for the concentrations tested. However, the EC50 value for NANOFER 25 (without the special surface modification) is 0,94 g·l-1 . These results confirm that it is necessary to...
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Ecotoxicological Evaluation of Polymers and Biologically Active Substances in Aquatic Environments
Kašpar, Otakar ; Beklová, Miroslava (referee) ; Chýlková, Jaromíra (referee) ; Kráčmar, Stanislav (referee) ; Vávrová, Milada (advisor)
To determine the ecotoxicity of analgetics, first the individual ecotoxicity values of individual analgetics are determined and then a mixture of two analgetics is tested. To determine the toxicity, both standard and alternative toxicity tests are used (daphnia magna, sinapsis alba, scenedesmus subspicatum, vibrio fischeri, thamnotoxkit FTM a daphnotoxkit FTM magna). The analgetics being whish tested are the commonly used medicines ibuprofen, ASA, diclofenac and paracetamol, which are the most frequently used medicines in the Czech Republic and whole Europe. To determine the ecotoxicity of the polymers, I‘m using an indirect method of examination, in which I determine the antagonistic or synergistic effects of the mixture of monomers from which the polymer is prepared and into which it slowly decomposes in nature. For the determination both standard and alternative toxicity tests are used. The polymers the toxicity of which is being determined are the habitually used polymer PET and the formaldehyde resine known as bakelite in Eastern Europe.
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