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Hazardous substances leasing from plastic bottles
Najmanová, Iveta ; Vopršalová, Marie (advisor) ; Pourová, Jana (referee)
v anglickém jazyce Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Iveta Najmanová Supervisor: PharmDr. Marie Vopršálová, CSc. Title of diploma thesis: Hazardous substances that are released from plastic bottles This master thesis focuses on hazardous substances that are released from plastic bottles. Attention is paid especially to bisphenol A and antimony and their effects after oral administration. Given the fact that these substances are harmful to humans, most of the information about their effects was observed in epidemiological studies or studies conducted on laboratory animals and human tissues. The thesis documents the toxicological effects on the body, especially of bisphenol A. To a lesser extent and primarily because of the limited number of studies on this topic, it deals with the influence of antimony. This is a search thesis and the data are the sum of bibliographic records on the subject.
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Study of properties of UV-photochemical generation of volatile compounds od antimony
Adámková, Dominika ; Červený, Václav (advisor) ; Hraníček, Jakub (referee)
The master thesis deals with comparison of atomic fluorescence spektrometry and high resolution continuum source atomic absorption spektrometry for three methods generation of volatile compounds Antimony. In both methods of atomic antimony detection, it compares the most common chemical generation of volatile compounds (hydrides) with two alternative methods - electrochemical and UV - photochemical. The values of performance parameters for the determination of Sb(III) and Sb(V) were determined for all the above combinations. In the case of chemical generation, a surprisingly almost four times higher limit of detection of Sb(III) was found in connection with AFS detection than AAS detection. The final part was devoted to UV - photochemical vapor generation, with AAS detection for Sb(III) reaching limit of detection 4,96 ppb, for Sb(V) 8,63 ppb. Although UV - photochemical generation of volatile antimony compounds did not reach such performance parameters as chemical or electrochemical generation, it was observed that the sensitivity of antimony determination increased greatly when introducing oxygen into the apparatus. The interference study also found a significant positive effect of Fe(II) on the generation efficiency, and this modification partially persisted without further introduction of these...
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Interferences in determination of antimony by electrochemical generation of volatile compounds and atomic fluorescence spectrometry
Kostúrová, Dominika ; Červený, Václav (advisor) ; Nováková, Eliška (referee)
Antimony is a highly toxic element that enters the environment through natural processes and human activities as well. It is necessary to determine its ultra-trace amounts in various materials such as water, soil and biological samples. Due to the heterogeneity of sample matrices, the determination of antimony is problematic because of frequent interactions. The aim of this work was to investigate the effects of various interferents on the determination of antimony by electrochemical generation of volatile compounds and atomic fluorescence spectrometry. In total, 18 interference dependencies were measured in the determination of Sb(III) and Sb(V). The following ions were selected for the interference study: SO4 2- , Cl- , NO3 - , NO2 - , Fe3+ , Fe2+ , As3+ , Se4+ and Bi3+ . The As3+ ion had the most interesting course of all the interferents and could be used as a suitable additive to increase the sensitivity of antimony determination.
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Interferences in determination of antimony by UV-photochemical generation of volatile compounds and atomic fluorescence spectrometry
Kračmarová, Aneta ; Červený, Václav (advisor) ; Hraníček, Jakub (referee)
This work is focused on the study of interferents of selected elements during UV-photochemical generation of volatile antimony compounds. The interferents included transition metals, halides, hydride-forming elements and salts of mineral acids. Detection was performed by atomic fluorescence spectrometry. Some of the tested added substances proved to be potential reaction modifiers; in their presence, an increase in responses was observed. The best results were obtained using Fe3+ for the determination of Sb3+ and SO4 2- had the best results for the determination of Sb5+ . The largest interferent, i.e. the substance causing the most significant decrease in signal, was for both antimony ions Se4+ .
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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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Determination of selected metals in tea samples and bag materials
Hlávka, Jan ; Nováková, Eliška (advisor) ; Hraníček, Jakub (referee)
This bachelor thesis is dealing with determination of antimony in materials modern pyramid-shape tea bags. Possible presence of antimony in these materials, e.g. polyethylene terephthalate (PET) or mixed materials, is caused by using it like catalyst in production of polyethylene terphthalete. The goal of this bachelor thesis is the verification of hypothesis, that antimony is present in materials of pyramide tea bags and that it is released to consumed drink, if higher concentration of antimony is present, and that it could pose a health risk to the consumer. At the same time, I studied if tea leaves are contaminated by other toxic elements, from which some can result from intesive agricultural production. They can be used as pesticides or be presnet in industrial fertilizers. In this thesis I examined the content of As, Cd, Cu, Sb and Zn in tea leaves sold in pyramide bags. These pyramide bags were purchased in local supermarkets and shops. The content of Sb in bags was determined too. The applied method included the decomposition of samples in a microwave decomposition device and analysis of the composition of the resulting solution by the ICP-MS method. Determined contents of the investigated elements were expressed like content of element in the sample in dry mass and the results were compared...
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Effect of lead and antimony on the degradation of graphite shape in cast iron
Hlobil, Albert ; Kaňa, Václav (referee) ; Záděra, Antonín (advisor)
The bachelor thesis focuses on the effect of lead and antimony on the degradation of graphite in cast iron in relation to the lowered mechanical characteristics. This leads to the subsequent summary of the formation of degraded structures and unfavourable elements – the elements that are the cause of the formation. In the practical segment of the thesis, I will prove the effects of lead (or the combination of lead and antimony) on the degradation of graphite in cast iron with the focus lying at flake graphite. Furthermore, the thesis examines the mechanical characteristics and the attenuation of cast iron in relation to the formation of degraded graphite structures.
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Study of properties of UV-photochemical generation of volatile compounds od antimony
Adámková, Dominika ; Červený, Václav (advisor) ; Hraníček, Jakub (referee)
The master thesis deals with comparison of atomic fluorescence spektrometry and high resolution continuum source atomic absorption spektrometry for three methods generation of volatile compounds Antimony. In both methods of atomic antimony detection, it compares the most common chemical generation of volatile compounds (hydrides) with two alternative methods - electrochemical and UV - photochemical. The values of performance parameters for the determination of Sb(III) and Sb(V) were determined for all the above combinations. In the case of chemical generation, a surprisingly almost four times higher limit of detection of Sb(III) was found in connection with AFS detection than AAS detection. The final part was devoted to UV - photochemical vapor generation, with AAS detection for Sb(III) reaching limit of detection 4,96 ppb, for Sb(V) 8,63 ppb. Although UV - photochemical generation of volatile antimony compounds did not reach such performance parameters as chemical or electrochemical generation, it was observed that the sensitivity of antimony determination increased greatly when introducing oxygen into the apparatus. The interference study also found a significant positive effect of Fe(II) on the generation efficiency, and this modification partially persisted without further introduction of these...
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