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Toxicity of microplastics and nanoplastics
Nechvátal, Marek ; Klouda, Karel
The article summarizes the knowledge about the influence of micro and nanoplastics on environmental components. Attention is paid to a complex set of the main toxic effects of plastic particles on selected groups of environmental organisms, especially new information and interactions with living organisms that have the potential to cause ecotoxicological damage.
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Nanofibres as part of respiratory protective devices, but also as a potential source of nano and microplastics to the environment
Klouda, Karel ; Bátrlová, Kateřina ; Roupcová, Petra
Increased production of nanofibers (nanotextiles) is causing a global pandemic for their application in protective equipment such as respirators, face shields, nanocoatings, nano knitwear. In essence, the materials from which these protective devices are made are a combination of non-woven fabrics and nanofibers deposited on textiles. The question is to what extent these products will affect the occurrence of nano and microplastics in the environment. This paper focuses on the acquisition and identification of sources of plastic nanoparticles (nanofibers) that are released into the environment. The following possible sources are compared: during the preparation of nanofibres by electrostatic softening; during the processing of nanofibre textiles into products such as respirators, nano-muffs; during mechanical stresses on nanofibre textiles, friction, abrasion; when used respirators, muffs are thrown on the soil grass, in puddles, in water, etc.
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Effects of microplastics on earthworm gut microbiome, their immunity system and metabolome
Flohrová, Tereza ; Cajthaml, Tomáš (advisor) ; Lišková, Petra (referee)
Microplastics are widespread pollutants found in aquatic, atmospheric, and soil environments. They are released directly into the soil, for example, from mulch films and textiles. Microplastics accumulate in the soil and can have a negative impact on soil microfauna and macrofauna. Earthworms, acting as ecosystem engineers, and soil and gut bacteria play a significant role in biogeochemical cycles of biogenic elements. Disruption of earthworm function, their gut bacteria, or soil bacteria could have an impact on the entire ecosystem. In the context of this thesis, earthworms of the species Apporectodea sp. were exposed to microplastics from polypropylene black nonwoven textile at concentrations of 1 g/kg soil and 0.0265 g/kg soil for 14, 28, and 56 days. DNA was sequenced to identify bacteria from the earthworm gut, gut contents, and rearing soil. Additionally, untargeted analysis of metabolites from the earthworm body and extraction of immune cells from earthworms using three different methods were conducted. No significant changes caused by the presence of microplastics were found in the representation of bacteria from the gut, gut contents, and soil, but statistically significant changes in the metabolome were detected. A sufficient number of immune cells could not be isolated from the...
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Microplastics in deep-sea fish
Fürychová, Barbora ; Cajthaml, Tomáš (advisor) ; Innemanová, Petra (referee)
Microplastics have become a significant problem in marine ecosystems, posing a serious threat to the biodiversity and stability of these environments. This bachelor's thesis focuses on investigating the presence of microplastics in the digestive tracts of deep-sea fish in the Indian Ocean. These fish represent interesting model organisms that can aid in understanding the distribution of microplastics in the marine water column. The introductory part of the paper summarizes the existing knowledge on microplastics, their occurrence, methods of analysis and the presence of microplastics in the aquatic environment. Particular attention is paid to deep- sea fishes, whose role in marine ecosystems is crucial. In the experimental part, detailed analyses of fish digestive tract samples were performed to detect and identify microplastics. The study confirmed the presence of microplastics in the digestive tracts of deep-sea fish, and various types of polymers were identified, including polystyrene, nylon, polyethylene terephthalate, polyvinyl chloride and polyester. This undergraduate thesis is the first study ever to demonstrate that microplastics are found in deep- sea fish in the western Indian Ocean. The conclusions of this thesis underscore the urgency of the situation regarding contamination of the...
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Analysis of Conditions for the Implementation of Dynamic Points in the Chemistry Curriculum as a General Education Subject - Microplastics
Marešová, Eva ; Bílek, Martin (advisor) ; Janoušková, Svatava (referee)
The diploma thesis focuses on the phenomenon of so-called dynamic points of curriculum, which represent the implementation of new non-traditional topics into the content of teaching reflecting the current results of technology development including their environmental context. In the theoretical part of the diploma thesis the concept of dynamic curriculum places is elaborated with a focus on the topic "Microplastics" in the teaching of chemistry as a general teaching subject as their current example. The practical part is firstly aimed to the design of teaching activities on the topic "Microplastics", supporting the implementation of this topic in the teaching of chemistry at lower secondary schools and in the corresponding grades of multi-year grammar schools. Subsequently, in the practical part, the specific conditions for the implementation of the topic "Microplastics" in the teaching of chemistry as a general teaching subject are analysed through two case studies, focusing on the information and material-technical conditions of lower secondary schools and multi-year grammar schools, including examination of the effectiveness and functionality of the proposed teaching activities supporting this implementation in schools through practice. The results of the analysis illustrate that the case of a...
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The separation of microplastics from environmental matrices
Pařízková, Mia Victoria ; Řezáčová, Veronika (referee) ; Doležalová Weissmannová, Helena (advisor)
This bachelor’s thesis deals with methods of separation microplastics from soil and the follow up application of quantitative methods of gravimetry, ATR-FTIR and Py-GC/MS. Samples containing model soil and PET or PLA microplastics of different concentrations were prepared. These samples were separated using potassium carbonate solution of known density. The effectivity of separation was measured by gravimetry. The samples were also analysed using ATR-FTIR and Py-GC/MS methods the results of which were compared by correlation coefficients. It was found that ATR-FTIR is a more suitable method, thus it was used for analysis of prepared samples of ten different real soils and PET or PLA microplastics.
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Design of a Vessel for Ocean Waste Collection
Šnajdr, Petr ; Paliatka, Peter (referee) ; Křenek, Ladislav (advisor)
The thesis deals with the problem of the exponentially increasing amount of plastic waste in the world's seas and oceans. The text discusses the causes of this problem and current efforts to address it, including an analysis of these efforts, on the basis of which new solutions are identified and proposed. The aim of the thesis is to design a vessel, including its operating system, that will enable the collection of floating waste from large bodies of water while being as sustainable as possible. The proposed vessel approaches the problem with a systemic solution that addresses not only the end problem but also its causes. To do this, it uses its configurable design between working and living versions. In both cases, the vessel collects floating waste through a unique system of two separable motorised floats that direct the waste to the vessel, where it is then scooped and processed by pyrolysis on board. In addition, the residential version of the vessel allows public accommodation on board, which will financially support operations while educating the community about the global problem of plastic pollution through media and experience. The operation of the vessel is as environmentally friendly and self-sufficient as possible through the use of renewable energy and semi-autonomous steering. Within this framework, an innovative device combining vertical wings propelling the vessel while integrating a rotating turbine generating electricity from wind power has been designed. The results of the work provide a systemic solution to the problem of plastic pollution in the oceans, which can not only be economically and environmentally sustainable, but also has a social impact. In addition, it offers a number of innovative technical and design solutions that can be applied in other technologies.
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The problematics of identification and quantification of microplastics in soils
Polachová, Tereza ; Pavlovský, Jiří (referee) ; Doležalová Weissmannová, Helena (advisor)
This bachelor's thesis summarizes the current findings on the presence, behavior and analysis of microplastics in soils. The most common method for analyzing microplastics in soils is FTIR spectroscopy. However, summaries of findings and results of published research indicate insufficient standardization of sampling, purification and handling of samples. The aim was to create a mathematical model for the quantification of PET in mixtures of standard soils and PET, which was subsequently verified on mixtures of PET in different real soils. The result is a model which should be universal for the quantitative analysis of PET in standard and real soils, with low and high PET concentration. Models were created for the following wavenumbers 2965.80 cm-1; 1739.99 cm-1; 1299.85 cm-1 and 1135.31 cm-1. The correlation coefficients R2 for individual wavenumbers were: 0.9606; 0.9141; 0.9360 and 0.8879.
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Study of the interaction of hazardous metal – microplastic
Sinčáková, Lenka ; Řezáčová, Veronika (referee) ; Doležalová Weissmannová, Helena (advisor)
Mikroplasty, široko zastúpené vo vodnom prostredí, slúžia ako vektor širokej škály kontaminantov, vrátane ťažkých kovov. Táto práca sa zaoberá adsorpciou piatich ťažkých kovov (Pb, Hg, Zn, Cu and Cd) na polyetylén tereftalát (PET), rozšírený polutant riek a morí. Pokiaľ ide o vplyv veľkosti mikroplastov na proces adsorpcie, nebol zistený jasný trend. Salinita prostredia má značný vplyv na adsorpčný proces s pozorovateľným poklesom adsorbovaných množstiev v prostredí s vysokou iónovou silou. Analyzované ťažké kovy boli zoradené vzostupne podľa ich schopnosti adsorpcie na PET nasledovne: Hg
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Evaluation of the effects of biodegradable microplastics on biota of freshwater ecosystem via ecotoxicity tests
Procházková, Petra ; Maršálek,, Blahoslav (referee) ; Beklová, Miroslava (referee) ; Zlámalová Gargošová, Helena (advisor)
Microplastics, which are ubiquitous contaminants of freshwater ecosystems, have raised concerns regarding their potential impact on the environment. For this reason, there is an effort to replace conventional plastics with biodegradable alternatives that can easily degrade in the environment. However, the process of biodegradation of these materials requires specific conditions, such as temperature, humidity, pH, and the presence of microorganisms, which are not always met adequately. Consequently, they may fragment and form biodegradable microplastics that can affect the environment similarly to conventional microplastics. Therefore, the aim of this study was to assess the impact of microplastics of biodegradable poly(3-hydroxybutyrate) microplastics on freshwater organisms, specifically the alga Desmodesmus subspicatus, the plant Lemna minor and the crustacean Daphnia magna. Additionally, we aimed to develop a suitable analytical method for the direct detection of microplastics in the body of D. magna. Although the observed effects were not always significant, they highlighted certain secondary problems that may arise due to the presence of biodegradable microplastics in the environment These issues could be related to biodegradability and the formation of biofilm on the surface of biodegradable microplastics, leading to subsequent nutrient depletion in the surrounding environment. Therefore, the use of biodegradable plastics as a substitute for conventional materials must be approached critically.
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