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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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Study on degradation processes of bioplastics
Fojt, Jakub ; Koutný, Marek (referee) ; Gregor, Tomáš (referee) ; Kučerík, Jiří (advisor)
Biodegradable bioplastics are currently developed as a more environmentally friendly replacement for conventional plastics to be used in agriculture or packaging materials. As the production of these products increases, so will the likelihood of introducing them in the environment. Biodegradable materials are expected to biodegrade rapidly, thereby they should reduce the number of microplastics in the environment. Biodegradability is currently determined by biodegradation tests, the parameters of which are defined in very general terms and often do not reflect the actual conditions under which the bioplastic will degrade in the environment. There is a lack of knowledge about the fate and impact of these particles in different ecosystems (especially in soil, where contamination is expected to be highest). Therefore, in this dissertation, we critically evaluate the ISO soil biodegradation test and extend it with a subsequent determination of bioplastic residues in soil. For this reason, an analytical method for the determination of polyhydroxybutyrate and polylactic acid microplastics based on methods used for the determination of conventional microplastics. The effect of microbioplastics on soil is also discussed, focusing on the effects that may pose problems in agriculture. The influence of microbioplastics on abiotic (soil water properties, soil structure) and biotic (soil diversity, nutrient cycling) soil properties immediately after their entry into the soil are described. The effect of biodegradation and long-term presence of microbioplastics in soil on soil organic matter, nutrient content, and soil microbial diversity (described by determining the activity of 5 key enzymes involved in carbon, nitrogen, and phosphorus cycling) are also studied. The last chapter demonstrates the potential problems that can be encountered when bioplastic products are applied in agriculture, where the growth of fungi and molds naturally occurring in the soil can be accelerated. As a result of this dissertation, a comprehensive view of bioplastics in the environment is presented, which can serve to assess the suitability of the application of current generation bioplastic products in agriculture and the possible management of bioplastic waste.
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Microplastics and plastics from view of law
Novák, Adam ; Sobotka, Michal (referee)
Microplastics and plastics from a legal perspective Abstract The dissertation deals with the management of microplastics from a legal point of view, following the ever-increasing pollution of the environment by plastics. The issue of microplastics has not yet been dealt with at this level in the Czech environment. The dissertation is not aiming only at the management of primary microplastics, which is most often dealt with by existing legislation at the level of individual states, but also at the management of secondary microplastics, which have been so far legally dealt with only by indirect regulation (through limiting plastic waste as a source of this type microplastics). The aim of the work is primarily to create an overview of the existing legislation of the management of microplastics at the international and European level (including individual legislation of the EU member states). Based on this overview is made an analysis of this legislation and are formulated proposals and recommendations for improving the management of microplastics, especially to limit their release into the environment. The dissertation is divided into nine chapters: The first chapter is the introduction, in which the grasp of the topic, research questions and the structure of the work, including the methods used, are...
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Influence of microplastics on aquatic organisms - an overview study
BÁRTOVÁ, Lucie
The aim of this bachelor thesis was to develop a review summarizing knowledge about the effect of microplastics on aquatic organisms. In recent years, negative impacts of microplastics on aquatic organisms have begun to be observed. This work clarifies the entry paths of microplastics to the water recipient and their occurrence in aquatic ecosystems. The effects of microplastics on aquatic organisms, both vertebrates and invertebrates and phytoplankton, were also presented. To work properly out this bachelor thesis, I have used Czech and foreign sources found in the scientist database. However, many studies are still needed to fully understand the impact of microplastics and deduce clear conclusions. In order to deduce general conclusions from the studies, it is necessary to standardize water sampling methods as well as methods for testing the effects on organisms.
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METHODS OF POLY-3-HYDROXYBUTYRATE EXTRACTION AND THEIR OPTIMIZATION
Pospíšilová, Aneta ; Plachá,, Daniela (referee) ; Kowalczuk, Marek (referee) ; Přikryl, Radek (advisor)
Poly-3-hydroxybutyrát (PHB) je biolodegradovatelný a biokompatibilní termoplastický polymer se širokou škálou potenciálních aplikací. Výroba PHB typicky zahrnuje fermentaci obnovitelných surovin bakteriemi. Získávání PHB z bakterií je však často náročné a neefektivní. V této práci jsou zkoumány a porovnány různé metody pro získání PHB, včetně digesce, mechanického rozrušení a extrakce. Jsou diskutovány různé optimalizační strategie, které lze použít ke zlepšení účinnosti izolace PHB. Experimentální a výsledková část popisuje snahy o zlepšení metod izolace, zejména kyselé a mýdlové digesce, které byly vybrány jako potenciálně ekonomické, bezpečné a šetrné k životnímu prostředí. Společně s našimi průmyslovými partnery jsme tyto technologie úspěšně otestovali v čtvrtprovozním měřítku a plánuje se další vývoj. Řešily se také možné aplikace a komercializace PHB. Bylo zjištěno, že PHB může nahradit některé mikroplasty v kosmetice a že toto úsilí má potenciál, protože přítomnost mikroplastů v běžných výrobcích je stále vysoká a na úrovni Evropské unie je plánován jejich zákaz. Dále byla studována tepelná stabilita PHB v závislosti na metodě získávání a byly vyvinuty dvě stabilizační metody, které umožnily použít PHB získaný digescí za použití mýdla v materiálových aplikacích.
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Microplastics and plastics from a legal perspective
Novák, Adam ; Damohorský, Milan (advisor) ; Fiala, Zdeněk (referee) ; Průchová, Ivana (referee)
Microplastics and plastics from a legal perspective Abstract The dissertation deals with the management of microplastics from a legal point of view, following the ever-increasing pollution of the environment by plastics. The issue of microplastics has not yet been dealt with at this level in the Czech environment. The dissertation is not aiming only at the management of primary microplastics, which is most often dealt with by existing legislation at the level of individual states, but also at the management of secondary microplastics, which have been so far legally dealt with only by indirect regulation (through limiting plastic waste as a source of this type microplastics). The aim of the work is primarily to create an overview of the existing legislation of the management of microplastics at the international and European level (including individual legislation of the EU member states). Based on this overview is made an analysis of this legislation and are formulated proposals and recommendations for improving the management of microplastics, especially to limit their release into the environment. The dissertation is divided into nine chapters: The first chapter is the introduction, in which the grasp of the topic, research questions and the structure of the work, including the methods used, are...
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Study of sorption of pharmaceuticals and compounds from personal care products to microplastics underfield conditions
Titov, Ivan ; Cajthaml, Tomáš (advisor) ; Innemanová, Petra (referee)
With the development of civilization and the chemical industry, a whole range of new anthropogenic substances is being introduced into the environment. Some of these substances are produced primarily - targeted for a specific purpose (e.g. pesticides and pharmaceuticals) and others are created as a by-product of chemical synthesis or they are degradation products of primary substances. Whether they are low-molecular substances or macromolecules, in addition to their positive effect on mankind, these substances can also retroactively threaten the environment, including humans. The present work deals with interactions between two groups of xenobiotics, which appear to be a huge global problem. As part of this work, the sorption of a wide group of substances belonging to pharmaceuticals and personal care products (PPCPs) on man-made microplastics from three types of polymers (PVC, HDPE, and PET) in real wastewater was studied. Two different locations were chosen for this experiment - effluents from wastewater treatment plants. Several sampling devices containing different types of microplastics were installed at these sites, including artificially aged alternatives that better reflect the behavior of microplastics found in real conditions. The results of these experiments showed the ability of...
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Microplastics in General Secondary Chemistry Education
Marešová, Eva ; Bílek, Martin (advisor) ; Janoušková, Svatava (referee)
The bachelor thesis focuses on microplastics as a frequently discussed topic in the context of environmental hazards, which despite its topicality and popularity is not included in the teaching of Chemistry as a general educational subject. The theoretical part focuses on the size classification, origin, composition, appearance, sources, and the occurrence of microplastics, including their impact on the environment. The first practical part consists of an analysis of the Framework Educational Programme for Elementary education, the Framework Education Programme for Grammar Schools, and selected Schools Educational Programmes with a main focus on microplastics. The second practical part is devoted to the design of learning activities through which pupils are able to actively learn about the topic of microplastics in the context of teaching Chemistry as a general education subject. This active form of familiarisation with the topic should aim at increasing the pupils' interest in learning about this topic and contribute to the awareness of the possible risks involved at the same time. KEYWORDS Microplastics, general chemistry at lower secondary and grammar schools, environmental education
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