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Evaluation of environmental load by perfluorinated compounds
Šima, Aleš ; Stoupalová, Michaela (referee) ; Vávrová, Milada (advisor)
The most important substances of the group of perfluorinated compounds are perfluorooctyl sulfonate (PFOS), perfluorooctanoic acid (PFOA) and perfluorooctane sulphonamide (FOSA). Perfluorinated compounds have special physical and chemical properties, which make them valuable for usage in different industrial branches. These properties, which make them so useful are also the reason, why they are so harmful for the environment. The target of theoretical part of the diploma thesis was processing of literature searche on the topic: Evaluation of environmental load by perfluorinated compounds. In the experimental part was developed and optimized a method that was used for the identification and quantification of selected pollutants contained in real soil samples.
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Study of Exposure PBDE and Perfluorinated Compounds into Aquatic Ecosystem
Vondráčková, Ilona ; Chýlková, Jaromíra (referee) ; Hroch, Martin (referee) ; Kráčmar, Stanislav (referee) ; Vávrová, Milada (advisor)
In the presented PhD. thesis, problems covering occurrence of polybrominated diphenyl ethers (PBDE) and perfluorinated compounds in the environment were solved. The study was focused on identification and further verification of optimal methods in order to determine PBDEs and perfluorinated compounds sampled from the aquatic ecosystem. Polybrominated diphenyl ethers belong to persistent compounds classified as main pollutants; within the environmental constituents, they have been observed particularly in the last decade. For these studies, there were selected surface water matrices and sediments taken in various localities within the river Svratka basin. The analyses were to demonstrate whether they accumulate and remain in these specific matrices for longer time. There we assessed the congeners of polybrominated diphenyl ethers as follows: BDE-28, 47, 66, 85, 99, 100, 153, 154 and 183. In order to isolate them from matrices, various extraction techniques were used, i.e., ultrasonic extraction, microwave extraction, and pressure solvent extraction. Gas chromatography method with electron capture detection (GC/ECD) was selected for determination. The accomplished studies also assessed basic chemical, physical and environmental characteristics of diphenyl ethers in the environmental constituents. The attention was also paid to perfluorooctanoic compounds (PFOA), (PFOS) and (FOSA); physico-chemical properties of these organic pollutants were characterised and their toxicological and environmental aspects were evaluated. Usability of extraction techniques (ultrasonic extraction, pressure solvent extraction, solid phase extraction) applied to PFCs isolation from sediments samples was assessed. Identification and quantification of these analytes were performed using a high performance liquid chromatography/mass spectrometry method (HPLC/MS). After that, the optimized methods applied to real samples. Surface water and sediments were sampled within the river Svratka basin, in particular, from 19 sampling localities. PBDE occurrence was confirmed in sediments samples from the Svratka river (g.kg-1), PBDE were not detected in the surface water samples, their concentrations were below the detection limit, resp.; perfluorinated compounds were not detected in sediments and water samples at all.
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Question of perfluorinated compounds in environmental compartments
Šima, Aleš ; Mravcová, Ludmila (referee) ; Vávrová, Milada (advisor)
The target of this bachelor work is processing of literature searche on the topic: Question of perfluorinated compounds in environmental compartments. The most important substances of the group of perfluorinated compounds are perfluorooctyl sulfonate (PFOS) and perfluorooctanoic acid (PFOA). Perfluorinated compounds have special physical and chemical properties, which make them valuable for usage in different industrial branches. These properties, which make them so useful are also the reason, why they are so harmful for the environment. The perfluoroalkyl chain is not affected by photolysis, hydrolysis or biodegradation. PFOS and PFOA are very persistent in the environment. The presence of the PFOS have been detected in liver, blood, muscle, kidney or brain of many animal species including the invertebrates over fish, amphibians, birds, mammals up to human being all over the world. An alarming fact is, that the high concentrations of PFOS have been found in arctic animals tissues far away from anthropogenic sources. Improved analytical techniques enabled scientists to take interest in perfluorinated compounds in more detail, which led to the identification of quite a number of these compounds. Nowadays there is an endeavour to eliminate the application of perfluorinated chemicals and replace them gradually by other compounds, which are better degradable and do not affect the environment.
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Novel perfluorinated compounds in the environment
Leifertová, Karolína ; Cajthaml, Tomáš (advisor) ; Innemanová, Petra (referee)
Perfluorinated compounds are a broad class of manmade chemicals. Even though they have been linked to hepatotoxicity, neurotoxicity, nephrotoxicity and carcinogenicity, the mechanism of toxicity still remains unclear. Only recently, two compounds (perfluorooctanesulfonic acid and perfluorooctanoic acid) have been phased out. This has led to a production of so-called "novel perfluorinated compounds". This work focuses on the evaluation of toxicity for 4 perfluorinated compounds, including the novel perfluorinated compounds (perfluorooctanesulfonic acid PFOS, perfluorooctanoic acid PFOA, hexafluoropropylene oxide dimer acid GenX, and hexafluoropropylene oxide trimer acid HFPO-TA). Gonadal and liver cell lines of rainbow trout were used for testing. Relevant toxicity tests were performed, such as viability tests (carboxyfluorescein diacetate, alamar blue and neutral red uptake), cytochrome P450 1A activation (ethoxyresorufin-o-deethylase, EROD) and measurements of reactive oxygen species generation (2',7'-dichlorofluorescein diacetate). HFPO- TA dramatically reduced viability and resulted in a statistically significant increase in intracellular reactive oxygen species. GenX caused an increase in EROD activity, but no effect on viability or reactive oxygen species formation was observed. The...
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Material design problems of plasma-chemical reactors for disposal perfluorinated compounds
Brožek, Vlastimil ; Březina, Václav ; Mastný, L. ; Kubatík, Tomáš František ; Živný, Oldřich
Reduction of perfluorinated gases emissions from semiconductor industry has recently introduced a serious problem from both technological and economic side. With respect to chemistry of the decomposition reactions the most effective abatement techniques developed up to now consists in the interaction of those gaseous pollutants with several types of plasmas. In the framework of Czech-Taiwanese bilateral project No. 17-10246J 'Decomposition of Perfluorinated Compounds and Fluorinated Ozone Depleting Substances' a new plasmochemical reactor design is to be solved. In this reactor the plasma abatement process consisting of interaction of the plasma generated by unique watter stabilized H-WSP plasma torch at temperatures ranging\nfrom 2000 K up to 25,000 K with the treated gases will be carried out. However, the main product generated in the reactor during the steam plasma abatement process is hydrogen fluoride which causes corrosion of almost every construction material. The aim pursued by the work presented is to search for the materials resistant to exposition of HF even at high temperatures. To investigate corrosion resistance of construction materials with thermal stability within temperature interval 2700-3000 °C titan nitride, boron nitride, and silicon carbide have been selected. The samples of those materials have been prepared by spark plasma sintering method and exposed to concentrated solution of hydrofluoric acid for which corrosion rates have been measured
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Study of Exposure PBDE and Perfluorinated Compounds into Aquatic Ecosystem
Vondráčková, Ilona ; Chýlková, Jaromíra (referee) ; Hroch, Martin (referee) ; Kráčmar, Stanislav (referee) ; Vávrová, Milada (advisor)
In the presented PhD. thesis, problems covering occurrence of polybrominated diphenyl ethers (PBDE) and perfluorinated compounds in the environment were solved. The study was focused on identification and further verification of optimal methods in order to determine PBDEs and perfluorinated compounds sampled from the aquatic ecosystem. Polybrominated diphenyl ethers belong to persistent compounds classified as main pollutants; within the environmental constituents, they have been observed particularly in the last decade. For these studies, there were selected surface water matrices and sediments taken in various localities within the river Svratka basin. The analyses were to demonstrate whether they accumulate and remain in these specific matrices for longer time. There we assessed the congeners of polybrominated diphenyl ethers as follows: BDE-28, 47, 66, 85, 99, 100, 153, 154 and 183. In order to isolate them from matrices, various extraction techniques were used, i.e., ultrasonic extraction, microwave extraction, and pressure solvent extraction. Gas chromatography method with electron capture detection (GC/ECD) was selected for determination. The accomplished studies also assessed basic chemical, physical and environmental characteristics of diphenyl ethers in the environmental constituents. The attention was also paid to perfluorooctanoic compounds (PFOA), (PFOS) and (FOSA); physico-chemical properties of these organic pollutants were characterised and their toxicological and environmental aspects were evaluated. Usability of extraction techniques (ultrasonic extraction, pressure solvent extraction, solid phase extraction) applied to PFCs isolation from sediments samples was assessed. Identification and quantification of these analytes were performed using a high performance liquid chromatography/mass spectrometry method (HPLC/MS). After that, the optimized methods applied to real samples. Surface water and sediments were sampled within the river Svratka basin, in particular, from 19 sampling localities. PBDE occurrence was confirmed in sediments samples from the Svratka river (g.kg-1), PBDE were not detected in the surface water samples, their concentrations were below the detection limit, resp.; perfluorinated compounds were not detected in sediments and water samples at all.
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Evaluation of environmental load by perfluorinated compounds
Šima, Aleš ; Stoupalová, Michaela (referee) ; Vávrová, Milada (advisor)
The most important substances of the group of perfluorinated compounds are perfluorooctyl sulfonate (PFOS), perfluorooctanoic acid (PFOA) and perfluorooctane sulphonamide (FOSA). Perfluorinated compounds have special physical and chemical properties, which make them valuable for usage in different industrial branches. These properties, which make them so useful are also the reason, why they are so harmful for the environment. The target of theoretical part of the diploma thesis was processing of literature searche on the topic: Evaluation of environmental load by perfluorinated compounds. In the experimental part was developed and optimized a method that was used for the identification and quantification of selected pollutants contained in real soil samples.
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Question of perfluorinated compounds in environmental compartments
Šima, Aleš ; Mravcová, Ludmila (referee) ; Vávrová, Milada (advisor)
The target of this bachelor work is processing of literature searche on the topic: Question of perfluorinated compounds in environmental compartments. The most important substances of the group of perfluorinated compounds are perfluorooctyl sulfonate (PFOS) and perfluorooctanoic acid (PFOA). Perfluorinated compounds have special physical and chemical properties, which make them valuable for usage in different industrial branches. These properties, which make them so useful are also the reason, why they are so harmful for the environment. The perfluoroalkyl chain is not affected by photolysis, hydrolysis or biodegradation. PFOS and PFOA are very persistent in the environment. The presence of the PFOS have been detected in liver, blood, muscle, kidney or brain of many animal species including the invertebrates over fish, amphibians, birds, mammals up to human being all over the world. An alarming fact is, that the high concentrations of PFOS have been found in arctic animals tissues far away from anthropogenic sources. Improved analytical techniques enabled scientists to take interest in perfluorinated compounds in more detail, which led to the identification of quite a number of these compounds. Nowadays there is an endeavour to eliminate the application of perfluorinated chemicals and replace them gradually by other compounds, which are better degradable and do not affect the environment.
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Occurrence of perfluorinated compounds in fish from rivers of the Czech Republic
HOLAŇ, Viktor
The object of this thesis is the assessment of fish contamination by selected foreign substances as perfluorinated compounds. these sites were selected for the thesis' purpose: Bečva - Dluhonice, Elbe - Přelouč, Bílina - Usti nad Labem, Jizera - Předměřice, Sázava - Nespeky and Otava - Topělec. Fish were caught by electrofishig. The concetrations of contaminants were measured in fish muscle and liver. The analysis were performed using liquid chromatography (HPLC - MS / MS). Concentrations of PFOS, PFNA, PFOA, PFHxS and PFHpS in fish muscle and liver tissues were monitored.
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