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.

Over the last 20 years increasing concentration of platinum metals in the environment was recorded. These hazardous metals come through anthropogenic activities in the aquatic and terrestrial ecosystem. It is therefore necessary to deal with their possible negative impact on organisms. This thesis is focused on the ecotoxicological evaluation of selected complex compounds of platinum metals, namely platinum and palladium. For ecotoxicity evaluation tests on following aquatic organisms were used: Daphnia manga, Thamnocephalus platyurus and Lemna minor. On the base of obtained results ecotoxicological values of LC50 and EC50 were calculated.

Endocrine disruptors are natural or manmade substances which affect hormonal systems of organisms. Biologically relevant concentrations are commonly being detected in the environment. The effluents of wastewater treatment plant present their significant secondary source. Due to their occurence and quantity the interest in mixtures increases. Ecotoxicological assays with genetically modified Saccharomyces cerevisiae were aplied to verify reliability of predictive mathematical models for mixtures of standards (estrone, 17β-estradiol, 17α-ethinylestradiol, estriol, bisphenol A, irgasan, 4-nonylphenol). Chromatographic analysis along with yeast assays were used for the evaluation of real samples of wastewater treatment plant effluents and sediments. Schindler's predictive model and Full logistic model (FLM) were more reliable for predicting the whole dose-response curve compared to Generalized concentration addition (GCA). Predicted values of a parameter EC50 from all three models were comparable to empirical measurements. Three out of four samples exhibited estrogenic activity 0.65 - 1.70 ng/L 17β-estradiol ekvivalent (EEQ) above the limit of detection 0.13 - 0.33 ng/L EEQ. Antiestrogenic activity was detected in one of the samples. Prediction could be carried out only in the case of the sediments...

The aim of this diploma thesis is to assess the ecotoxicological effect of biochar produced from sewage sludge. In case of application of biochar to agricultural land, both the soil and aquatic ecosystem may be affected therefore contact and aquatic tests were chosen to assess the ecotoxicological effects. Representatives of soil invertebrates were earthworms Eisenia fetida; Daphnia magna and Artemia salina were chosen from aquatic animals and terrestrial plants were represented by Lactuca sativa, Sinapis alba and Allium cepa. The results of contact tests point out how ecosystem could be negatively affected by biochar dose. Through aqueous extract were shown differences in sensitivity of individual organisms in aquatic tests. Dried sewage sludge was found to be the biggest burden for all tested organisms. The pelletized biochar with the addition of an additive showed the lowest negative effect on tested organisms.

Environmental effects of selected monomers, eventually aditives of polymers, will be evaluated by ecotoxicity tests. For this purpose two alternative tests of toxicity: Thamnotoxkit F TM on testing organism Thamnocephalus platyurus and Daphnotoxkit F TM on testing organism Daphnia magna will be used. Two phytotoxicity tests will be also used: Sinapis alba root growth inhibition toxicity test and Allium cepa L root growth inhibition toxicity test. Obtained results enable calculation of value LC50, EC50 and IC50 for tested substances.

Určení vlivu volby zkušebního organismu na výsledek stanovení toxických účinků. Porovnání výsledků stanovení akutní toxicity mikrometodou při použití 5 různých druhů sladkovodních řas (podle TNV 75 7741), vyhodnocení rozdílů v citlivosti použitých druhů, optimalizace metodických postupů.

Thousand of new substances with unknown environmental effect are produced and used daily. Many of them are deliberately or by negligence released and deposited into the environment where they could undergo different transport and degradation mechanisms. They are able to affect different types of organisms, as well as humans. For this reason, the awareness of the problems, associated with pollution of all environmental compartments is growing. The environmental impact of monomer formaldehyde resins, which are produced for commercial use, on the environment were studied in this research. For the purposes of ecotoxicological evaluation samples of melamine-formaldehyde and urea-formaldehyde resin were chosen and three toxicity tests were run: acute test with measurement of inhibition of the mobility of Daphnia magna, the acute test with luminescent bacteria Vibrio fischeri and acute test with measurement of inhibition of oxygen consumption by activated sludge. For more comprehensive assessment of the impact of these substances on the environment, biodegradability was also determined. Both tested substances showed minor hazardous impact to testing organisms and it can be concluded, that these substances should not present a significant risk to the environment.

In recent years consumption of drugs and thus the quantity of their residues in natural ecosystems is increasing. It is necessary to deal with their possible negative effects on the environment. This thesis is focused on the ecotoxicological evaluation of pharmaceuticals. Diclofenac and ibuprofen from the group of non-steroidal anti-inflammatory substances, penicillin G and ampicillin from the group of antibiotics were tested. Mainly tests on aquatic organisms were used to evaluate of ecotoxicity, because the tested pharmaceuticals are predominantly occurred in the aquatic environment. Daphnia magna, Thamnocephalus platyurus, Artemia salina, Sinapis alba, Lemna minor, and Brachionus calyciflorus were used as testing organisms. Values of LC50, EC50 and IC50 were determinated and the ecotoxicity of pharmaceuticals was compared.

The energetic byproducts are a part of energetic wastes which are residues of fuels combustion or also the residues of flue-gas cleaning. Their following application can impact the terrestrial and subsequently also aquatic ecosystems. With respect to these reasons it is necessary to deal with their possible ecotoxicity. Within the framework of this diploma thesis water leaches from the byproducts’ samples were prepared and subsequently ecotoxicaly tested. Three alternative toxicity tests on aquatic organisms were used: Thamnotoxkit FTM and a Rapidtoxkit FTM on sense organisms Thamnocephalus platyurus and Daphtoxkit FTM on sense organisms Daphnia magna. Standard tests of fytotoxicity were also used; Sinapis alba root growth inhibition test and Lemna minor growth inhibition test. The values of EC50, LC50 and IC50 were determined and ecotoxicity of energetic byproducts was evaluated.

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.