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Mikroplasty a jejich vliv na životní prostředí
Kopicová, Jana
This bachelor thesis deals with plastic pollution in the environment predominantly focusing on microplastics. The aim of the theoretical part is to acquaint readers with the terminological background of plastics and their microscopic parts. This part also contains an overview of current information about sources, presence, and possible impact of microplastics in the environment centring on the water component. The theoretical part further discusses the effect of microplastics on living organisms and one’s health. In the practical part of the thesis, a questionnaire survey was carried out to find out respondents’ opinions and awareness of the given matter. The results of the survey confirmed that most of the respondents, despite being familiar with the term microplastics, are not well informed about their impact on the environment. The survey also indicates that this area lacks public awareness. Furthermore, a comparative analysis shows that more than 80% of the respondents would be in favour of refundable plastic bottles. Finally, the survey appears to confirm that respondents have poorer knowledge in legal regulations dealing with plastic waste.
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Mikroplasty v mořských plodech a jejich dopad na lidské zdraví
Formanová, Michaela
This bachelor thesis summarizes current knowledge regarding the accumulation of microplastic particles in the marine fauna and their impact on marine organisms. The uptake of microplastics has been demonstrated in laboratory and natural conditions in various marine organisms, including zooplankton, oysters, mussels, and shrimp. Microplastic particles are transferred from lower to higher taxonomic levels through the food chain via trophic transfer. The model transport within the food web was studied in a marine crab that was fed with mussels contaminated with microplastics. Microplastic fragments were able to penetrate from the crab's gastrointestinal tract into surrounding tissues. Microplastics are receiving a lot of attention in research as potential carriers of dangerous chemicals. The consequences of microplastic contamination on the food chain and human health are not sufficiently explored and require further study.
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Occurrence and removal of polluting organic substances during drinking water treatment
Prokopová, Michaela ; Pivokonský, Martin (advisor) ; Brányiková, Irena (referee) ; Kříženecká, Sylvie (referee)
Water sources pollution by natural organic substances and anthropogenic micropollutants is a global problem with a significant impact on water treatability and drinking water quality. One of the current topics is the proliferation of algal and cyanobacterial cells and the associated release of algal organic matter (AOM). The presence of AOM in drinking water sources can deteriorate the water's taste and odour or serve as precursors of disinfection by-products., especially in the case of a high proportion of the non-proteinaceous AOM, which is difficult to remove by conventional coagulation/flocculation. A part of this thesis is devoted to the composition and characterization of AOM, its chemical coagulation and electrocoagulation, and the assessment of the ozonation of the non-proteinaceous AOM during drinking water treatment. The second part of this thesis deals with the occurrence, characterization and removal of persistent anthropogenic substances, namely microplastics (MPs) and per- and polyfluoroalkyl substances (PFAS), during the drinking water treatment. Based on the results of ozonation of the non-proteinaceous AOM fraction (NP), it was found that ozonation caused a change in the surface charge, molecular weight or partial mineralization of NP, depending on ozonation conditions (O3 dose, pH...
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Identification of PET particles in soils and their influence on the environment
Šudomová, Lucie ; Svěrák, Tomáš (referee) ; Slovák, Václav (referee) ; Kučerík, Jiří (advisor)
This thesis is focused on several issues connected with plastics and their impact on the environment. Although plastics are produced for a relatively short time, they have taken a dominant position in almost all industries and aspects of everyday life. However, this causes significant challenges related especially to the waste management. If plastics are not handled properly, they can contaminate the environmental compartments where they are gradually defragmented and degraded, and macro and microplastics are formed. Both qualitative and quantitative analysis of microplastics in soil is a big challenge. In this work, it is introduced a new method based on mutual relationships between soil components called Soil Universal Model Method (SUMM). The method allowed to identify and quantify some types of microplastics in the untreated soil. It appeared to be effective in the analysis of PET, PVC and PP. A pilot study on the influence of PET microplastics on soil revealed negative effects, which include soil organic matter deterioration and faster desiccation. In addition, it was observed a gradual assimilation of PET into the soil matrix, and possible degradation, in particular at low pH values. To identify the origin of PET fragments occurring in nature it was developed a method based on PET thermophysical properties (determined using Differential Scanning Calorimetry, DSC) and advanced statistical methods. This method appeared to be effective also for the assessment of PET quality in recycling loop and classifies the PET into four groups. It was also found that controlled thermal degradation under laboratory conditions does not correlate with natural PET degradation (aging). A method based on spectroscopic parameters (FTIR) is also presented here, but it did not achieve such unambiguous results as using DSC, because it determines the molecular structure of the polymer, which proved to be insufficient for identifying changes during the PET recycling cycle.
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Brominated and iodinated disinfection by-products
Bednář, Jiří ; Načeradská, Jana (advisor) ; Kopecká, Ivana (referee)
The reaction of a disinfectant with natural organic matter in the presence of bromides and iodides in raw water intended as a source of drinking water produces brominated (Br-DBPs) and iodinated disinfection by-products (I-DBPs) of water. These tend to be more cytotoxic and genotoxic than their chlorinated analogues. However, little information is available on these products compared to chlorinated ones. Therefore, the aim of this work was to provide an overview of natural and anthropogenic sources of bromine and iodine containing substances, to determine their influence on the formation of brominated and iodinated disinfection by-products, and to compare their cytotoxicity and genotoxicity with chlorinated products. Increasing seawater intrusion into the groundwater drinking water source was found to increase the concentrations of Br-DBPs and I-DBPs by up to thousands of percent. A number of substances can be released from water pipe material depending on the material. These include, for example, tenorite and copper cation released from copper piping, iron cation released from cast iron and steel piping, and bromides and dissolved organic carbon (DOC) released from plastic piping. All of these corrosion products contribute to increasing concentrations of DBPs in the distribution network. Both seawater and...
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Use of the organism Daphnia magna in a multigenerational ecotoxicity test
Klasová, Kristýna ; Maršálková, Eliška (referee) ; Zlámalová Gargošová, Helena (advisor)
This bachelor thesis deals with the multigenerational effect of microparticles of the biodegradable polymer polyhydroxybutyrate (P3HB) on the freshwater organism Daphnia magna. The presence of microplastics in the environment is a frequently discussed environmental problem, hence efforts are being made to develop biodegradable plastics that would degrade more easily in the environment. The most studied biopolymer P3HB, however, there is not much information on its ecotoxicity yet. In the context of this work, ecotoxicity was assessed using a multigeneration assay; in addition, the effect of P3HB microparticles was compared to that of naturally occurring particles. Multigeneration assays are not yet commonly used for ecotoxicological evaluation, but they offer a comprehensive and realistic view of the effect of the test substance on the test organisms. In this work, 4 generations of D. magna were exposed to P3HB microparticles and kaolin microparticles for comparison. The results showed no negative effect on the mortality of the organism, but a slight decrease in reproductive activity was observed.
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Preparation and characterization of polyhydroxybutyrate-based particles
Kopřivová, Lenka ; Šindelář, Jan (referee) ; Pospíšilová, Aneta (advisor)
This bachelor's thesis deals with the preparation of particles with a modified surface based on poly 3 hydroxybutyrate and the subsequent characterization of both modified and untreated particles. The particles were examined with a vision for future replacement for non degradable commodity microplastics in the cosmetics industry, as they are capable of biodegradation. The following chemicals were used for surface treatment: zinc stearate solution, lipase, hydrophobic silane (hexadecyltrimethoxysilane) and cationic surfactant. Next, the properties of the resulting modified particles were studied in comparison with unmodified poly 3 hydroxybutyrate and polyurethane-based powder, which is currently used in the cosmetic industry, and therefore served as a standard for sensory analysis. All samples were subjected to SEM and EDS analysis, FTIR spectroscopy and sensory analysis. Then, the following properties were measured: wettability, bulk density and particle size distribution by laser diffraction. Wettability was measured on compressed tablets from the powders using static contact angles. It was found that the hydrophobicity of particles treated with silane and zinc stearate increased, whereas the particles treated with cationic surfactant increased in hydrophilicity. The results measured from the contact angle and other analyses led to the conclusion that the surface treatment with lipase was not successful. Sensory analysis showed that the surface treatments did not affect the deterioration of the sensory properties compared to the original untreated PHB powder and that an untrained evaluator cannot tell the differences in pleasantness between the samples therefore, we can consider them as pleasant as the standard we determined.
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Preparation of polyethylene terephthalate model microplastics
Hrušková, Adéla ; Fojt, Jakub (referee) ; Kučerík, Jiří (advisor)
Microplastics are ubiquitous in all ecosystems and for that reason they became a subject of many studies in recent years. Due to their stability, potential release of harmful additives and ability to adsorb pollutants, they pose a threat to the environment. It was found that certain microplastics can, under certain conditions, have toxic effects on fauna, flora and human health. Most of studies include laboratory or mesocosmos testing, therefore, it is important to master their preparation. To study the environmental impact of microplastics, it is essential to be able to prepare these particles, especially required type, shape and size. This bachelor thesis deals with the preparation of model polyethylene terephthalate particles using physical and chemical methods. The physical preparation is based on the cryomilling, in which individual milling parameters are tested and it is investigated their effect on the milling efficiency and the size of the milled particles. The chemical preparation method is based on the dissolution of polyethylene terephthalate in a solvent and subsequent precipitation. In this case, the size, shape of the prepared particles and the content of residual solvent adsorbed on the particles were monitored. At the end of the work, it was concluded that the tested preparation methods are not suitable to prepare microplastics useable for environmental studies because the prepared particles do not have the required size or contain the residues of the used solvent.
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Microplastics and their effects on the metabolism of animal cells
Fiedlerová, Gabriela ; Cajthaml, Tomáš (advisor) ; Černý, Jan (referee)
Microplastics are tiny particles smaller than 5 mm in size found in various environments, including seas, rivers and soil. These particles can be intentionally produced as part of cosmetic products or formed by the breakdown of larger plastic objects. Microplastics represent a serious threat to the environment and animals and could eventually reach humans through the food chain. This thesis deals with a critical and synthetic overview of the literature related to the influence of microplastics on the metabolism of animal cells. The thesis also considers the experimental conditions under which the data were obtained. In particular, factors such as the tested microplastics' shape, size and ageing are critically evaluated as these aspects are often neglected in the literature. Current knowledge shows that microplastics accumulate in the bodies of animals and cause physical and metabolic damage, inflammation, disruption of energy metabolism, protein metabolism and amino acid and lipid metabolism. The most serious effects of microplastics can be considered to be the formation of oxygen radicals, neurotoxicity, disruption of gametogenesis and offspring development.
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Application of FTIR methods for the determination of microplastics in soils
Vishneuskaya, Ulyana ; Pavlovský, Jiří (referee) ; Doležalová Weissmannová, Helena (advisor)
This bachelor thesis deals with the application of methods of infrared spectroscopy (ATR-FTIR) and thermal analysis (py-GC/MS) for the determination of microplastics in soil. Part of the thesis is an analysis of the current state of knowledge in the field of occurrence of microplastics in the terrestrial environment, their transmission in the soil and potential risks. The experimental part includes the preparation of samples of a mixture of model soil and PET of different concentrations and their analysis using ATR-FTIR and further isolation of PET from the samples by density separation and analysis by the py-GC/MS method. Based on the correlation coefficients, which show the ratio between the measured and actual values, it was considered that ATR-FTIR is more suitable for qualitative and quantitative analysis of microplastics in soil, and therefore this method was used to evaluate real soil samples with PET.
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