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Ecotoxicity tests on cellular level
Procházková, Petra ; Vávrová, Milada (referee) ; Zlámalová Gargošová, Helena (advisor)
Endocrine disrupting compounds among significant environmental pollutants. They are dangerous both for humans and other organisms by affect their hormonal system. They enter the environment during production, use and disposal some chemicals, but they may be of natural origin. The aim of this work is to give a brief overview of possible methods of determination of the presence of ecotoxic substances in the environment, using the in vitro toxicity assays. These tests use cell cultures instead of test organisms. The work describes principles of ecotoxicity tests at the cellular level, such as cell viability assays, cell proliferation assays, assays based on the metabolic activity of cells or DNA microarrays. A significant part of this work is focused on the possibilities of determination of endocrine disruptors by selected assays. They are ligand binding assays, reporter gene assays (recombinant yeast assay, mammalian-based reporter gene assays) and cell proliferation assay called E-screen. Significance and rationale use of tests to prove the endocrine activities in environmental matrice is given through examples of studies in which the tests were used.
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Ecotoxicity of substances with hormonal effect
Cvikýřová, Zuzana ; Vávrová, Milada (referee) ; Zlámalová Gargošová, Helena (advisor)
This bachelor thesis deals with the fate and ecotoxicity of chosen substances with hormonal effect in the environment. This group of compounds covers steroid hormones, which are produced for these effects, but also a lot of xenobiotics, showing similar activity. The substances disrupt the endocrine system by various mechanisms. They can cause feminization, masculinization, disruption of reproduction, etc. In terms of chemical structure they belong to the group of phthalates, polychlorinated biphenyls, pesticides, heavy metals and others. The impact of these substances, especially on the aquatic ecosystem, which becomes their reservoir in most cases, was assessed.
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The ecotoxicological evaluation of musk compounds
Lapčíková, Alena ; Beklová, Miroslava (referee) ; Doležalová Weissmannová, Helena (advisor)
This master’s thesis is focused on evaluation of synthetic musk fragrances using ecotoxicity tests. Four musk fragrances were tested – Galaxolide, Tonalide, Musk ketone and Musk xylene. Four alternative ecotoxicity tests with living organisms, one standard ecotoxicity test and three fytotests were used for evaluation of ecotoxicity. Alternative tests were performed on crustaceans Daphnia magna and Thamnocephalus platyurus, brine shrimp Artemia salina and rotifer Brachionus calicyflorus. Root growth inhibition test of Sinapis alba, root growth inhibition test of Lactuca sativa, root growth inhibition test of Allium cepa and growth inhibition test of Lemna minor were performed in the terms of fytotests. On the basis of the results the values of EC50, IC50 and LC50 were determined and the ecotoxicity of musk compounds was evaluated.
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The use of algal test in ecotoxicology
Hájková, Tereza ; Zlámalová Gargošová, Helena (referee) ; Doležalová Weissmannová, Helena (advisor)
This diploma thesis deals with a use of algal test in ecotoxicology. A freshwater algae, Desmodesmus subspicatus, was used to asses the ecotoxicity of selected chemical substances. A spectrophotometry method, of VIS spectrum, was used in evaluation of the EC50. A correlation, between a number of algal cells and the wavelength absorbance at 683 nm, has been determined for this purpose. Following chemicals were tested, 2-[2-[(2,6-dichlorophenyl)amino]phenyl]acetic acid, (RS)-2-[4-(2-methylpropyl)phenyl]propanoic acid and N-(4-hydro-xyphenyl)acetamide. An EC50 value was determined for all these substances and also their ecotoxicity has been evaluated.
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Waste water toxicity.
Urminská, Barbora ; Vávrová, Milada (referee) ; Zlámalová Gargošová, Helena (advisor)
The theoretical thesis is focused on evaluation of toxicity of wastewaters and effluents and also on specification of legislative requirements related to the subject. As the negative effects of effluents on receiving water do not always depend on presence and concentrations of toxic chemicals contained in the effluent, analyses of physical and chemical parameters only is not sufficient and does not provide adequate results. The aim of the thesis is to show the importance of using ecotoxicological biotests as a necessary part of whole effluent toxicity assessment and to describe approaches to this testing in the European Union countries.
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Sewage sludge and sediments evaluation via ecotoxicity tests
Ondrová, Jana ; Vávrová, Milada (referee) ; Zlámalová Gargošová, Helena (advisor)
Sediments and sewage sludges are part of the environment. Sewage sludges are formed in wastewater treatment plants as solid residues after water purification, therefore they have antropogenic origine. Although the sediment are formed by natural processes, humans also contribute to their formation. Sediments and sewage sludges can be a reservoir of a number of contaminants, due to their properties. Utilisation of sediments and sewage sludges as material for recultivation or a natural fertilizer is currently supported. But after application to the land, contaminants can be released to the environment. The consideration of ecotoxicological effects of sediments and sewage sludges is very important. Sediments and sewage sludges were ecotoxicologicaly evaluated by bioassays with water leacheate and by whole sediment bioassays. Daphnia magna, Thamnocephalus platyurus, Sinapis alba and Lemna minor were used to perform tests with water leacheate. Heterocypris incongruens, Lactuca sativa and Eisenia fetida were used to perform whole sediment tests.
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Importance of contact tests of ecotoxicity
Modlitbová, Pavlína ; Doležalová Weissmannová, Helena (referee) ; Zlámalová Gargošová, Helena (advisor)
This bachelor thesis is dealing with an issue of contact tests of ecotoxicity and their importance for solid matrices testing as wastes, contaminated soil etc. According to the requierements of current legislative, ecotoxicity of these materials is evaluated only for results obtained with testing their water leach. Need of insertion ecotoxicity contact tests into mandatory set of tests is discussed in thesis, because current set of tests is relevant only for water ecosystem and does not support sufficient prediction for eventual ecotoxicologic impacts for terrestrial ecosystem.
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Use of selected toxicity tests on organisms Eisenia fetida in assessing ecosystem contamination by selected drugs.
Kašpárková, Petra ; Vávrová, Milada (referee) ; Zlámalová Gargošová, Helena (advisor)
Constantly increasing consumption of drugs leads to the increase of the concentration of residues in various environmental compartments. For this reason the drug residues are nowadays classified as significant environmental contaminants. The drug residues enter the soil along with the application of sewage sludge either as a fertilizer or during fertilizing by animal excrements excreted after drug administration, eventually by direct contamination from treated grazing animals. The presence of these substances in soil has got negative impact on the sensitive soil ecosystem. The diploma thesis aims to evaluation of possible soil contamination with selected drugs through ecotoxicity tests. For this purpose sulfonamide chemotherapeutic agents, which are often used in veterinary medicine, were chosen, specifically sulfamethoxazole and sulfamethazin. Eartworms (Lumbricus) were selected as suitable test representative soil organism. In the experimantal part of this work the avoidance test according to ISO 17512-1 and modified bioaccumulation test according to OECD 317 methodology were performed. Bioaccumulation substances in oligochaetes, for which the artificial soil was prepared according to OECD 207 methodology, which was subsequently contaminated with above specified drugs. Although according to the results of determination of these substances there is no significant bioaccumulation in eartworms‘ tissue, these organisms are very responsive to the presence of contaminants in the soil environment. This is evident from the results of avoidance tests.
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Ecotoxicological evaluation of sediments
Dobešová, Zuzana ; Doležalová Weissmannová, Helena (referee) ; Zlámalová Gargošová, Helena (advisor)
Sediments of lotic and lentic water can be a reservoir of a number of contaminants, which can enter the aquatic ecosystem either due to the controlled discharge of waste water or leakage of various accidents or technological devices. Sediments can hereby affect not only the aquatic ecosystem, but also the terrestrial system in the case that they will be used as fertilizer or as a material for the recultivation. For this reason it is important to consider their potential ecotoxicity. Sediments were subjected to ecotoxicological bioassays and their potential ecotoxicity was assessed. The phytotoxicity assays on terrestrial plants Sinapis alba, Lactuca sativa and Allium cepa were used and the effects of aqueous extracts of sediments on the inhibition of growth their root were evaluated and the value of IC50 was determined. For the ecotoxicological assessment of sediments and determination of IC50 value also Lemna minor as a representative of aquatic plants was selected. For more objective assessment of the sediment ecotoxicity aquatic invertebrates as Artemia salina and Daphnia magna were selected and the value of LC50 or EC50 was determined.
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