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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 the risk elements and other elements concentration in animal feed
Křehlíková, Jana ; Juglová, Zuzana (referee) ; Diviš, Pavel (advisor)
This thesis deals with the determination of selected microelements and macroelements and risk elements in dog and cat food. The theoretical part describes the nutrition of dogs and cats and focuses on the safety of the food in the context of contamination with risk elements. Another topic discussed is the chemical analysis of feeds, specifically the determination of nutritionally important substances, beneficial elements, and contaminants. The experimental part deals with the preparation and digestion of feed samples and the subsequent analysis of these samples using ICP-OES and AAS methods. The detected concentrations of the elements of interest in the feeds were compared with the feed standards issued by the Department of Veterinary Medicine and the decree issued by the Ministry of Agriculture. The analysed feeds were found to be deficient in some elements. The content of the risk elements in the feed met the legal limits and did not pose a health risk to the animal. Elements for which the legislation does not provide a maximum permissible limit were present in the feed-in in high concentrations that could already harm the animal's health.
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Study of surface water quality in the Ivančice area
Jonášová, Simona ; Řezáčová, Veronika (referee) ; Komendová, Renata (advisor)
Selected physical and chemical water quality parameters were measured at four sampling localities on the Jihlava River. Using UV-VIS spectrophotometry, inorganic forms of nitrogen, chlorides, total phosphorus and CODCr were determined. BOD5 was determined by the dilution method. Na+, K+ and Ca2+ ions, whose concentrations ranged from 5,75–108 mgl 1, were measured by flame emission photometry. Selected metals (Cu, Ni, Pb, Zn, Hg, Cr, Fe, Mn) were determined in water by the ET-AAS method. Decomposed sediments were determined by the FAAS method. Concentrations of Cr, Cu, Pb and Ni in water were in the range of 0,05–2,84 gl1. Metal concentrations in sediments ranged from 0,02–293 mgkg1, where nickel concentrations were above the limit. The occurrence of iron and manganese is due to the geological subsoil. For the other elements, anthropogenic source is assumed. From the measured data, the water quality is slightly variable in this locality and is classified as fourth or fifth class, i.e. as highly polluted water.
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Assessment the impact of the application of excavated sediments from the dam Luhačovice on the content of risk elements in arable soil
Kratěnová, Pavla ; Komendová, Renata (referee) ; Řezáčová, Veronika (advisor)
This diploma thesis focuses on an issue concerning an excavated sediment application on an arable soil and its impact on the soil quality based on a particular case of a deposition of the sediment from the dam Luhačovice on an adjacent agricultural area. The theoretical part of this thesis is focused on a soil and sediment characteristics and functions, contained risk elements, sampling methods, determination possibilities of particular risk elements and a description of conditions which emerged from a need for the deposition of sediment obtained during scavenging of the dam Luhačovice. In the experimental part was described the process of sampling, samples processing and determining of concentration values for chosen risk elements (Cd, Cu, Hg, Ni, Pb) using flame or electrothermal atomic absorption spectrometry methods. This part also contains an evaluation of obtained results and a validation of an approval for the sediment deposition.
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Contamination of soil and sediment by hazardous metals
Pidima, Tomáš ; Komendová, Renata (referee) ; Doležalová Weissmannová, Helena (advisor)
This bachelor thesis deals with soil and sediments from the environmental perspective. For selected heavy metals – cadmium, lead and mercury are given information about their occurrence, characteristics and potential sources of environmental contamination. It is also mentioned legislation dealing with the topic. The limit concentrations in soil and sediments, determination methodology and principles of the most commonly used instrumental analytical methods for these elements are described.
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Exogenic alteration of geomaterials with anomalous content of hazardous elements
Udatný, Martin
of dissertation thesis Exogenic alteration of geomaterials with anomalous content of hazardous elements The research of waste materials from high temperature processes belongs to current issues solved in the field of modern environmental geochemistry. Current research has mainly been focused on fly ash and bottom ash coming from metallurgy, combustion and other industrial processes. In these wastes of different grain size, accumulation of hazardous elements occurs. These elements may be present in low concentrations in combusted coal or municipal solid waste or it may come from ore processing. Hazardous compounds are also intentionally added during the technological process (e.g. making of lead glass). Modern industrial plants are equipped with effective filtration systems, but this might not be in the past. In the Czech Republic and elsewhere in the world old environmental burdens are and will be addressed. Current modern filtration systems are never 100% efficient. Contamination of surrounding environment in a lesser extent can still occur. The production of lead glass (Bohemian Crystal) is based on the addition of lead compounds in the glass raw material. Additions of these substances providing a high refractive index of the finished product. Also compounds containing other hazardous elements...
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Content of risk elements in food for dogs and cats
Hrabalová, Karolína ; Slavíková, Zuzana (referee) ; Diviš, Pavel (advisor)
This bachelor's thesis deals with the determination of risk elements, namely mercury, arsenic, cadmium and lead in dog and cat food. The concentration of mercury was determined using the AAS technique, and the concentration of arsenic, cadmium and lead was determined by the ICP-MS method after microwave decomposition of the samples using mineral acids. A total of 30 feed samples were analyzed. In most samples, the concentrations of monitored elements were lower than the maximum permissible values given by the EU Commission Regulation, two samples did not meet the requirements of the regulation. The concentration of risk elements in the feed, except for arsenic, did not depend on the type of meat used in the feed. Feeds containing fish meat showed demonstrably higher concentrations of arsenic than feeds with other meats. Due to the relatively low proportion of meat in feed and due to the overall lower concentrations of risk elements in meat, it can be assumed that the vegetable or other component of the feed, or the technology of feed production, is responsible for the increased concentration of risk elements in feed.
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Sewage sludge – a secondary source of environmental contamination with heavy metals
Sysel, Petr ; Zlámalová Gargošová, Helena (referee) ; Komendová, Renata (advisor)
This work deals with the elementary trace analysis of sewage sludge as a potential source of risk elements when applied to agricultural land. A total of 24 samples were analyzed, divided into two sets with different collection dates. The total content of zinc, copper, chromium, lead, mercury and cadmium in sewage sludge, as well as amount of risk elements that are extracted from sludge to water in 24 hours, was determined. Atomic absorption spectrometry was chosen for the analysis. It was found that the risk elements are in sewage sludge in amounts and order Zn (254.68 – 3084.53 mg/kg) > Cu (6.18 – 961.89 mg/kg) > Cr (26.95 – 387 .91 mg/kg) > Pb (0.84 – 155.30 mg/kg) > Hg (0.50 – 4.12 mg/kg) > Cd (0.06 – 2.61 mg/kg). A lower amounts of analyzed metals in the aqueous extracts than their total amounts in sludges were observed. The concentration of mercury and cadmium in the aqueous extracts was below the detection limits. It was evaluated that the risk elements in sewage sludge are found in less water soluble compounds. The results also show that the concentration of risk elements in the sludge does not depend on the number of equivalent inhabitants for which the treatment plant is dimensioned.
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