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Toxicity of selected nitramines
Papírek, Jan ; Fojt, Pavel (referee) ; Bednařík, Karel (advisor)
This Bachelor Thesis is focused on determination of toxicity of selected nitramines and nitrosoamines, which had to be synthesized soon. Out of total 10 prepared N-nitro and N- nitrosocompounds 4 were selected for testing their toxicity in test using Duckweed (Lemna Minor). Factor IC50 was determined for two compounds 3,7-dinitro-1,3,5,7-tetraazabicyclo [3.3.1]- nonane (DPT) and 3,7-dinitroso-1,3,5,7-tetraazabyciclo [3.3.1] nonane (DNPT), unfortunately factor for other compounds failed to determine, because conditions of test validity hadn’t been kept. In the end of the thesis is compared toxicity of N-nitro and N-nitrosocompounds based on results and observations.
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The study of PET bottles in terms of the content of risk elements
Kryštofová, Petra ; Řezáčová, Veronika (referee) ; Komendová, Renata (advisor)
This bachelor thesis deals with the issue of PET bottles in terms of the possible content of risk elements. The contents of antimony, copper and lead were determined in the PET packaging material and in the beverages contained in the bottles. A total of 15 samples of bottled still and infant water available in the Czech sales network were analyzed. The PET material was decomposed in an acidic medium under the action of microwave radiation under optimized conditions. Atomic absorption spectrometric methods with flame or graphite cuvette atomization were used to determine selected risk elements based on the predicted analyte concentrations. In the PET packaging material, 159.35 to 265.68 mgkg-1 of antimony were determined, the determined values of lead concentration were in the range of 10.96-20.23 mg·kg-1 and the copper concentration in the range of 0.11-7,52 mg·kg-1. In bottled water and in bottled infant water, antimony was identified only in samples labeled 6a, 8a, 9a and 15a, all lead concentrations were measured below LODPb, copper was determined only in samples 2a, 6a and 8a. In none of the samples did the concentrations given by the valid legislation be exceeded. The limits of these metals are not set in legislation in the packaging materials, only specific migration limits and they have not been exceeded. However, the high concentration of antimony in PET poses a potential risk of contamination of the contents of these packages.
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Evaluation of ecotoxicity of selected chemicals with using algal test.
Kosárová, Hedvika ; Pavlovský, Jiří (referee) ; Doležalová Weissmannová, Helena (advisor)
This bachelor thesis deals with the ecotoxicity of 2 - [(2,6-dichlorophenyl)aniline] benzene acetic acid (diclofenac), ?-methyl-4-(2-methylpropyl) benzene acetic acid (ibuprofen) and mixture of cadmium and diclofenac and studies the above using algal toxicity test in accordance with ISO 8692. The theoretical part describes the issue of pharmaceuticals in the environment, and characteristics of standards algae tests and alternative tests. Freshwater green algae Desmodesmus subspicatus were used as testing organisms in all the implemented algal toxicity tests. By the means of these tests, the IrC50 values for the standard substance potassium dichromate, the drugs diclofenac and ibuprofen and cadmium were determined. The toxicity of cadmium in mixture with diclofenac was also evaluated.
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Biotransformation of nitro aromates
Tomeček, Jaromír ; Bednařík, Karel (referee) ; Friedl, Zdeněk (advisor)
Contamination by nitroaromatic compounds, such as explosives, pesticides or other nitroaromatic compounds, is worldwide environmental problem. This text focuses on contamination by compounds from military and ammunition industry, most especially 2,4,6-trinitrotoluene (TNT), 1,3,5-trinitro-1,3,5-triazinane (RDX) and 1,3,5,7-tetranitro-1,3,5,7-tetrazocane (HMX). First goal of this work is to provide the reader with a aerobic biodegradation and transformation processes of nitroaromatic compounds named above. The second goal is to compare the toxicity of initial nitroaromates and their transformation intermediates.
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Evaluation of environmental load by perfluorinated compounds
Šima, Aleš ; Stoupalová, Michaela (referee) ; Vávrová, Milada (advisor)
The most important substances of the group of perfluorinated compounds are perfluorooctyl sulfonate (PFOS), perfluorooctanoic acid (PFOA) and perfluorooctane sulphonamide (FOSA). Perfluorinated compounds have special physical and chemical properties, which make them valuable for usage in different industrial branches. These properties, which make them so useful are also the reason, why they are so harmful for the environment. The target of theoretical part of the diploma thesis was processing of literature searche on the topic: Evaluation of environmental load by perfluorinated compounds. In the experimental part was developed and optimized a method that was used for the identification and quantification of selected pollutants contained in real soil samples.
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Arsenic and arsenic species cycle in environment
Ševčíková, Kateřina ; Sommer, Lumír (referee) ; Dočekalová, Hana (advisor)
This bachelor thesis, based mostly on literature retrieval, deals with monitoring of individual arsenic compounds in the environment and is also reviewing methods used for their analysis. The experimental part is focused on determination of various arsenic in the Oncorhynchus mykiss tissue by HPLC-UV-HG-AFS. Obtained results showed that the arsenic was present in the tissue of the Oncorhynchus mykiss in form of arsenobetaine, which is common for fishes and other aquatic animals and is not toxic even for consuments.
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Synthesis of quantum dots for in-vivo imaging
Ferdusová, Helena ; Majzlíková, Petra (referee) ; Pekárková, Jana (advisor)
The aim of this work was to synthesise water-soluble QDs using different precursors and stabilizers and to determine the toxicity of the synthesized QDs by in vivo imaging. Experiments were performed on water-soluble QDs (MPA-CdTe, MPA-CdTe/ZnS, MSA-CdTe, MSA-CdTe/ZnS, GSH-CdTe, GSH-CdTe/ZnS, TGA-CdTe, TGA-CdTe/ZnS, GSH-ZnSe and GSH-ZnSe/ZnS ) and toxicity was measured. Synthesized QDs were characterized by high intensity (fluorescence spectroscopy), FWHM and zeta potential (ZS Zetasizer) were selected due to their suitability for this task. The toxicity of QDs was determined by the MTT assay on the cell line HEK 293. The experiments show that a core/shell structure is less toxic than a core structure. The results indicate that the toxicity of our synthesized QDs is the lowest for MPA-CdTe (core structure) and MPA-CdTe/ZnS (core/shell structure).
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Chromium and chromium species cycle in environment
Nevrlá, Jana ; Sommer, Lumír (referee) ; Dočekalová, Hana (advisor)
This work focuses in the first theoretical part mainly on the possibility of entering various forms of chromium into the environment, their accumulation and transformation in environmental compartments. There are also described methods of sampling for analytical determination of chromium, the type of treatment of these samples and the most analytical methodologies for the determination of chromium in the oxidation stage III and VI. The experimental part is focused on the quantitative determination of Cr(III) and Cr(VI) in waste water, taken from the neutralizatoin station of the Chemical faculty of Brno University of Technology, by using selected spectrophotometric methods and the obtained results are compared with the results of analytical determination of total chromium by atomic absorption spectrometry.
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Assessment of Hazards of Hazardous Chemical Industrial Toxic Substances
Poláček, Tomáš ; Hradil, Jaroslav (referee) ; Mika, Otakar Jiří (advisor)
This thesis focuses on the overall risk exposure of hazardous industrial chemical toxic substances on the human body, describes the physical and chemical properties of the substances, their toxicological properties and environmental hazards. In the practical part is made methodology for assessment of hazards of hazardous chemical industrial toxic substances, depending on the selected properties. Furthermore, is made the basic statistics of actions of the Fire Department of Southern Region to hazardous chemicals in the years 2006 - 2010.
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