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Mixture toxicity of estrogenic endocrine disruptors in samples from the Czech Republic
Černá, Tereza ; Cajthaml, Tomáš (advisor) ; Klusoň, Petr (referee) ; Šváb, Marek (referee)
The environment is contaminated by countless toxic chemicals of mainly anthropogenic origin; therefore, elucidating the impact of chemical mixtures is one of the biggest challenges of current research. Endocrine disruptors (EDs) acting through the oestrogenic nuclear receptor are typical representatives of the mixture toxicity concept of concentration addition, which can be accurately predicted using the latest mathematical models. Oestrogenic activity and oestrogenic EDs have been detected in many matrices across the globe in biologically relevant concentrations; therefore, they are considered a high risk. The presence of synthetic steroids in the aquatic environment in units of ng/l can disrupt the hormonal pathways of individuals and subsequently cause fatal changes in whole populations. However, if the exposure is terminated, the ecosystem will recover in a few years. Wastewater treatment plants (WWTPs) are able to remove a large number of chemicals, including synthetic and natural oestrogenically active compounds; nevertheless, their occurrence in WWTP effluents and in sewage sludges is frequent. Therefore, WWTPs are considered significant sources of agricultural and water ecosystem pollution. This dissertation thesis focuses on the mixture toxicity of oestrogenic EDs and their occurrence in...
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Ecotoxicity of herbicidal ionic liquids
Müllerová, Tereza ; Cajthaml, Tomáš (advisor) ; Klusoň, Petr (referee)
Herbicidal ionic liquids (HILs) are organic salts with herbicidal properties. Their anions are usually derived from traditional herbicides, and they are paired with cations of a synthetic or natural origin. Because of their hydrophobic nature and lower volatility, HILs are considered an environmentally friendlier alternative to traditional herbicides, which often persist in the environment, contaminate groundwater and are toxic even to non-targeted organisms. Nevertheless, the scientific research on HILs is mainly focused on their effects on plants. In this thesis, the hormonal activity of selected HILs was tested using human cell lines. In addition, the ecotoxic effect of HILs on soil microorganisms was assessed using the analysis of phospholipid fatty acids (PLFA). To study the ecotoxic effect, two different types of soil were incubated with HILs in a 28-day experiment. The soils were characterized by a different management approach - the soils were treated or untreated with pesticides in the past. The effect of the content of soil organic matter and clay minerals on how HILs interact with soil microorganisms was evaluated. The residual concentrations of HILs were quantified during the soil experiment to assess the effect of the management approach applied in the past on the degradation rate of...
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Measurement and toxicity of combustion generated nanoparticles
Sikorová, Jitka ; Topinka, Jan (advisor) ; Klusoň, Petr (referee) ; Bláha, Luděk (referee)
This thesis is focused on nanoparticles produced by internal combustion engines utilized in vehicles. It deals with spatial distribution of nanoparticles within urban areas, impact of alternative fuels usage on particle production and toxicity, and a particle toxicological testing methodology. Monitoring of airborne nanoparticles identified traffic as the main source of airborne nanoparticles in places with heavy traffic load (Prague), as well as in a small city with only local traffic (Čelákovice). Most particles were likely emitted during short episodes of high emissions (e.g. uphill acceleration). During the measurements, high-emission vehicles responsible for a large fraction of the air pollution were also identified. On the other hand, small non-road internal combustion engines, which are not subject to any limit on particle emissions, such as a lawn mower, were operated during the measurement and generated a large number of nanoparticles. The amount and characteristics of the particles produced by combustion depend on the combustion technology and the fuel composition. A large part of the thesis deals with alternative fuels and their effects on the quantity of produced particles and toxicity of organic matter adsorbed on the particles. Hydrotreated vegetable oil (HVO) exhibited the lowest...
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Electrocoagulation method for treatment of polluted waters
Krušinová, Zuzana ; Klusoň, Petr (advisor) ; Mašín, Pavel (referee)
Many drinking water treatment facilities face problems with algal organic matter (AOM) due to eutrophication of the environment and frequent occurrence of algal blooms. AOM can cause deterioration of water organoleptic properties, but the main threat is the potential for acting as a precursor of toxic disinfection by-products (DBPs). The presented master thesis deals with the possibility of using electrocoagulation (EC) - an innovative electrochemical method - to remove cellular organic matter (COM) produced by cyanobacteria Microcystis aeruginosa from drinking water. EC is similar to widely used chemical coagulation, the difference is that during EC the coagulant is produced by electrochemical dissolution of an iron or an aluminum electrode. Synthetic water with COM concentration of 5.5 and 8.5 mg/L of TOC was used for the experiments. The target value of conductivity (4.5 mS/cm) was reached by addition of NaCl. pH of the solution was adjusted by HCl and NaOH. During some of the experiments, NaHCO3 was added to increase the ANC4.5. The experiments were conducted in a batch mode with a stainless-steel cathode and an aluminum or an iron anode. The coagulant dosage was regulated by applied electric current passing through the electrodes. Flocs were separated by sedimentation and centrifugation. COM...
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Microfluidic reactors for chemical synthesis
Jaklová, Natalie ; Klusoň, Petr (advisor) ; Cvak, Ladislav (referee)
The main topic of the Diploma Thesis is the conversion of the batch N-alkylation reaction into a continuous regime. It is the reaction of 10α-methoxydihydrolysergic acid methyl ester to 1-methyl-10α-methoxydihydrolysergic acid methyl ester. It represents one step in the industrial synthesis of Nicergoline, a pharmaceutical used for senile dementia treatment. This methylation reaction is performed in two immiscible liquid phases. Phase-transfer catalysis is used to increase the efficiency of the reaction, which allows the reaction to proceed in the entire volume of the organic solvent, not only at the phase interface. The reaction is rapid, with an exothermic character. The advantages of continuous arrangement are better control of the reaction, increased operational safety due to handling smaller volumes of reaction components, and more intensive removal of heat of the reaction. The Thesis deals with the influence of reaction conditions on the course of the reaction in a microfluidic reactor. The glass microchip reactor was chosen to perform the reaction in a flow arrangement. This reactor could produce up to grams of the product per hour. Several series of experiments were performed on this apparatus. The conversion of the starting material, and selectivities to the product and the side products...
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Measurement and toxicity of combustion generated nanoparticles
Sikorová, Jitka ; Topinka, Jan (advisor) ; Klusoň, Petr (referee) ; Bláha, Luděk (referee)
This thesis is focused on nanoparticles produced by internal combustion engines utilized in vehicles. It deals with spatial distribution of nanoparticles within urban areas, impact of alternative fuels usage on particle production and toxicity, and a particle toxicological testing methodology. Monitoring of airborne nanoparticles identified traffic as the main source of airborne nanoparticles in places with heavy traffic load (Prague), as well as in a small city with only local traffic (Čelákovice). Most particles were likely emitted during short episodes of high emissions (e.g. uphill acceleration). During the measurements, high-emission vehicles responsible for a large fraction of the air pollution were also identified. On the other hand, small non-road internal combustion engines, which are not subject to any limit on particle emissions, such as a lawn mower, were operated during the measurement and generated a large number of nanoparticles. The amount and characteristics of the particles produced by combustion depend on the combustion technology and the fuel composition. A large part of the thesis deals with alternative fuels and their effects on the quantity of produced particles and toxicity of organic matter adsorbed on the particles. Hydrotreated vegetable oil (HVO) exhibited the lowest...
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Utilization of tissue cultures for toxicology of the environment.
Polanská, Daniela ; Cajthaml, Tomáš (advisor) ; Klusoň, Petr (referee)
5 Abstract Five substances from the group of so-called personal care products, known for their low degradability and regular environmental detection, were tested for toxicity using two fish tissue lines (RTgill-W1 a RTG-2) isolated from rainbow trout (Oncorhynchus miykiss). The tested substances were hexadecylpyridinium chloride (HDP), chlorhexidine (CHX), octenidine (OCT), thymol (THM) and triclosan (TCS). A cell viability assay was performed with each of these compounds using Alamar Blue ™ (AB), 5-carboxyfluorescein diacetate acetoxymethyl ester (CFDA-AM) and neutral red (NR) protocols. The results were used to construct dose-response curves along with an EC50 value for each of these substances. The EC50 values ranged from 0,51 (HDP) to 33,75 µg.ml-1 (THM) for RTgill-W1 and from 0,31 (HDP) to 33,37 µg.ml-1 (THM) for RTG-2. The theoretical LC50 estimation was calculated according to Tanneberger et al. (2013). For all substances, cytochrome P450 1A activity was monitored using 7-ethoxyresorufin-o-deethylase (EROD), four out of five tested chemicals were statistically positive for EROD, the highest EROD response was observed for the most toxic compound - HDP. Only TCS did not show statistically significant cytochrome P450 1A activity. In addition, oxidative stress was measured with the fluorescent dye...
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Fluorinated micropollutants in the environment
Hatasová, Nicolette ; Cajthaml, Tomáš (advisor) ; Klusoň, Petr (referee)
Perfluorinated compounds (PFCs) are considered as persistent organic pollutants. Their extensive use in various products leads to increase of their occurence in surface and ground water, soil, air and, generally, in the global ecosystem. In this diploma thesis, method for detection and quantification of 19 perfluorinated compounds was developed. This method was used for analysis of real drinking water and sewage sludge samples from Czech Republic. It is based on pre-extraction step and consecutive liquid chromatography with mass spectrometry, using negative chemical ionization (LC-MS). We developed a method for analysis of water samples, using solid-phase extraction (SPE). Using this method, concentrations of PFCs in 8 samples of drinking water from Czech Republic were evaluated. Total concentration of analyzed PFCs was 4 - 23 ng/L. Processing of sewage sludge samples using accelerated solvent extraction (ASE) showed matrix effect, which influenced ionization and led to false positive/negative results. For supression of the matrix compounds, we used SPE Envi-Carb columns. Using this optimised method, 23 sewage sludge samples from different locations in Czech Republic were analyzed. The most represented PFC in the environment, perfluoroctane sulfonate (PFOS), was detected in concentrations 5 - 386...
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Preparation of optically pure compounds by stereoslective hydrogenation in a microreactor
Jaklová, Natalie ; Klusoň, Petr (advisor) ; Paterová, Iva (referee)
This bachelor Thesis is introducing an alternative approach to the synthesis of the pharmaceutically important compound (R)-4-chloro-3-hydroxybutyrate ((R)-CHBE). This compound is used as a precursor in the production of pharmaceutically valuable products, such as L-carnitine, (R)-4-amino-3-hydroxybutyric acid and (R)-4-hydroxy-pyrrolidone. At present time these chemicals are predominantly produced by using biochemical methods largely based on enyzmatic reactions in the presence of stereoselective carbonyl reductases. In this Thesis a new approach is described, which is based on stereoselective hydrogenation of ethyl-4-chloracetoacetate catalyzed by an optically pure ruthenium bis(phosphine) complex. The whole process was carried out in a microfluidic reactor system. This assembly is highly promising for a potential scale-up, studies of reaction kitetics, optimization of reaction and process conditions etc. For the reaction described above the optimal reaction conditions, such as temperature, pressure, solvent phase composition and flow rates of gas and liquid phases, were determined. Furthermore, the use of a suitable ionic liquid preserving the catalyst's chiral selectivity was described. Key words: (R)-4-chloro-3-hydroxybutyrate, L-carnitine, microfluid chip reactor, hydrogenation
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Possibilities of Zn Recovery from Waste Incineration Fly Ashes.
Korotenko, Ekaterina ; Šyc, Michal ; Jadrný, J. ; Mašín, J. ; Krystyník, Pavel ; Klusoň, Petr
Modern economy is characterized by unprecedented increase in the consumption of raw materials and products. Heavy metals represent only 10% of all inorganic goods consumed, but due to their specific physical and chemical properties they are extremely important in everyday life. Zinc is the world's 4th most widely used metal. Due to the reduction of easily accessible natural resources and the growing shortage ofZn, it is necessary to find secondary raw materials and methods to recover metal from them. Fly ash from municipal solid waste incinerators (MSWI) is a suitable raw material for Zn recovery, because of the production quantity and the same content of Zn as in poor ore. Thereby, this paper is aimed to the recovery of Zn from fly ash on the real scale from data obtained from MSWI in the Czech Republic. Verification of the possibility of Zn recovery from fly ash through acid extraction with flue gas treatment system scrubber liquid has been carried out. The results were compared with the published results of Zn recovery using the Swiss technology FLUWA/FLUREC and the Swedish HALOSEP. The average efficiency of Zn extraction in the real MSWI is close to 60%, which is comparable to the efficiency of the technologies mentioned above. Other benefits of acid extraction are above all the neutralization of two hazardous waste streams from the MSWI (fly ash and scrubber liquid), the reduction of chemicals consumption and the total costs for treatment of fly ash and scrubber liquid, production of stabilized inorganic residues and shifting the process in the waste management hierarchy from landfilling towards metals recovery.
Fulltext: content.csg -  PDF
Plný tet: SKMBT_C22019040814151 - PDF
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