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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.
Treatibility of surface water
Fuks, Josef ; Palčík,, Jiří (referee) ; Kučera, Tomáš (advisor)
The aim of the master´s thesis is the topic of the treatability of surface water with the focus on the process of suspension formation. For this work I took water samples from five different places around the Brno Dam which has contended with water quality deterioration for a long period. With these water samples, the series of jar coagulation tests were done with the application of three different commonly used coagulants. In the theoretical part of the master´s thesis I deal with the composition and attributes of surface water and the technology of its treatment. Each process of treatment is briefly described here with the emphasis on the process of suspension formation. The experimental part of the master´s thesis summarizes and presents the results gained through the coagulation tests in the laboratory. I evaluate the influence of different parameters on final effectiveness of water treatment and I try to find an optimal amount of coagulant, pH and speed of fast or slow mixing. Finally I compare the suitability of each coagulant and the influence of the sampling site on the effectiveness of water treatment.
Aplication of gas chromatography for determination of drug residuals in waters
Lacina, Petr ; Stoupalová, Michaela (referee) ; Vávrová, Milada (advisor)
Diploma thesis is focused on the choose of methods and optimalisation analysis procedure of selected pharmaceuticals (salicylic acid, ibuprofene, naproxene, ketoprofene and diclofenac) in surface and waste water by using gas chromatography with mass spectrometer (GC-MS). Solid-phase extraction (SPE) with Oasis HLB cartridges was used as an extraction method in this analysis. Extraction is followed by derivatization and their optimalization of selected pharmaceuticals. Derivatization and its optimalization were performed by two silylation reagens N-methyl-N-(trimethylsilyl)trifluoroacetamide (MSTFA) and N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA). Different volumes of derivatization reagents, different temperatures and different times were used during the procedure. The best combination is then used for analysis of real samples. Real samples of waste water were collected in sewage treatment plants in Brno – Modřice and real samples of surface water were collected from several rivers and one pond in region Moravia. This thesis also presents and tests SPE methods for extraction and concentration selected sulfonamide residues (sulfamethazine, sulfamethoxazole, sulfapyridine and sulfathiazole) from the aquatic environment.
Application of spectrophotometry for determination of drug residua in waters
Čapka, Lukáš ; Čáslavský, Josef (referee) ; Zlámalová Gargošová, Helena (advisor)
Residua of pharmaceuticals represent biologically active compounds which can interfere with some purification processes in WWTP. Control laboratories of many WWTP and water works are equipped with UV-VIS spectrophotometers. Therefore, the main goal of this thesis was the elaboration of the method for the determination of selected drugs in water based on the VIS spectrophotometry.
The issue of determination of beta-blockers in surface waters
Košík, Juraj ; Píšťková, Veronika (referee) ; Vávrová, Milada (advisor)
This bachelor´s thesis deals with the issue of increasing concentration of pharmaceuticals in the environment. The most worldwide prescribed medications with the most frequently detection in the environment are -blockers. These compounds are clinically important drugs which are extensively used for the treatment of cardiovascular disorders such as hypertension, arrhythmia and angina pectoris. It is important to monitor the concentration levels of blockers in aquatic environment due to their acute and chronic toxicity towards aquatic organisms. This study is focused on development and optimization of analytical method of determination of these compounds. The monitored matrixes were surface water from two rivers, Váh (Slovakia) and Dyje (Czech Republic) and waste water form waste water treatment plant (WWTP) Brno-Modřice. The analytes from water samples using solid phase extraction (SPE) were isolated. For the final analysis ultra-high performance liquid chromatograph with UV-VIS detection using diode array detector (DAD) was used. As the target compounds atenolol, metoprolol and propranolol were selected.
The Usage of Separation Methods for Research of Biologically Active Substances in Waters
Vydrová, Lucie ; Friedl, Zdeněk (referee) ; Opatřilová, Radka (referee) ; Chýlková,, Jaromíra (referee) ; Vávrová, Milada (advisor)
Pharmaceuticals are biological active compounds with different functional groups, physico-chemical and biological properties. These chemical compounds are called as “new contaminants” which cumulate in various environmental components. These contaminants input to environment from industrial processes, hospitals and health care institutions or household sources and these pollutants can to negatively interact with environmental components. Pharmaceuticals are separated according to structure and their effects to live organisms. On the basis of drug consumption in Czech Republic the non-steroidal anti-inflammatory drugs are the most using pharmaceuticals, because these drugs can be obtain without prescriptions. The choosing analgesics for study were monitored in waste water from waste waters treatment plant (WWTP Brno – Modřice) and in surface water from two sampling sites of river Kretinka. Pharmaceuticals were monitored in surface waters in Czech Republic, in Scotland (river Thurso) and in Taiwan (river Erren, Agongdian, Yanshuei and canal of Tainan) Solid phase extraction (SPE) is used for extraction of study pharmaceutical from water system. The high performance liquid chromatography (HPLC) with diode array detection or mass spectrometry was used for determination of drugs in surface waters from Czech Republic. The water samples from Scotland and Taiwan were analysed and the high performance liquid chromatography with mass spectrometry (HPLC/MS) was used for determination of pharmaceuticals. The method of HPLC/MS enables the determination of study compounds in the very low range of concentrations (ng ? l-1). All monitored pharmaceuticals were identified and quantified in water samples from river Kretinka in Czech Republic, river Thurso (Scotland) and rivers Erren, Agongdian, Yanshuei and canal of Tainan in Taiwan and the obtained data were compared.
Application of Gas Chromatography with Mass Spectrometric Detection for the Assessment of Drug-residue Contamination of Wastewaters and Surface Waters
Lacina, Petr ; Čáslavský, Josef (referee) ; Hajšlová, Jana (referee) ; Sokol,, Jozef (referee) ; Vávrová, Milada (advisor)
This work is based on the current issue of increasing concentrations of pharmaceutical residues in various components of the environment. These new environmental contaminants continuously enter the environment. The most affected environmental component is the aquatic environment. This study is focused on the development and optimization of reliable analytical method, which can determine selected drugs in the aquatic environment (waste waters and surface waters) qualitatively and quantitatively. The target compounds were selected mainly from the group of non-steroidal anti-inflammatory drugs (NSAID): salicylic acid, acetylsalicylic acid, clofibric acid, ibuprofen, acetaminophen, caffeine, naproxen, mefenamic acid, ketoprofen and diclofenac. NSAIDs are one of the most used drugs in Czech Republic. For the final analysis of this study was used the comprehensive two-dimensional gas chromatography with mass spectrometric detection Time-of-Flight (GCxGC-TOF MS). It is a very sensitive and reliable analytical method for trace and ultra-trace analysis. Simultaneously, solid phase extraction (SPE) and derivatization are optimized in this work. Optimized analytical method including SPE, derivatization with MSTFA (N-methyl-N-(trimethylsilyl) trifluoroacetamide) and final analysis by GCxGC-TOF MS were applied successfully for the analysis of real samples. Samples of waste water were collected from the waste water treatment plant in Brno – Modřice and samples of surface water were collected from two river streams Svratka and Svitava in Moravian region. The range of concentrations of selected drug residues varied from one to tens of g/L in wastewater and from tens to hundreds of ng/L in surface waters. The degree of wastewater and surface waters contamination by drug residues is assessed in conclusions of the work. Simultaneously, spontaneous degradation of selected drugs in water and removal efficiency of the wastewater treatment plant is assessed in conclusions of the work. The developed method is usable for monitoring and environmental analysis of water ecosystems. It is usable not only for selected drugs, but even for other organic compounds with similar properties.
Quality of surface water in the Czech Republic and their treatability
Bedáňová, Jana ; Macsek, Tomáš (referee) ; Biela, Renata (advisor)
The thesis deals with the quality of surface water in the Czech Republic and the development of its quality in the streams and reservoirs. Issues related to wastewater discharge to the recipient (often without cleaning) and seepage from agricultural land. At the end, it deals with water quality indicators, their acquisition and assessment based on normative documents and their calculation on the basis of measured values.
Hormonally active substances in the aquatic environment and risk to aquatic organisms and human.
Duisembay, Zhuldyz ; Bušová, Milena (advisor) ; Ezechiáš, Martin (referee)
This bachelor thesis aims to investigate the presence, sources and impacts of hormonally active substances, or endocrine disruptors (EDs), in the aquatic environment. These substances, including long-lived persistent organic pollutants (POPs), e. g. pesticides and polycyclic aromatic hydrocarbons (PAHs), and non-persistent pollutants such as bisphenol A and alkyphenols, directly or indirectly affect the hormonal systems of aquatic organisms and humans. For instance, it was observed, that elevated concentrations of certain progestogens impact fertility, reproductive processes, induce transcriptional changes, and alter sex ratios within fish populations. Numerous studies in the field focus on evaluating the manifestation of EDs in water, their effects on behavior and vital functions of aquatic organisms and humans, and the challenges associated with their detection and removal from the wastewater discharged into the environment. Recent researches have revealed elevated concentrations of specific EDs in various regions, including Czech Republic (significant concentrations of levonorgestrel, megestrol acetate (MGA), drospirenone and dienogest were detected in Blanice river). This indicates a lack of regulations and potential difficulties in effectively removing these substances from water with...
Dynamics of dissolved organic carbon in surface water during extreme rainfall-runoff events
Matoušková, M. ; Fraindová, K. ; Bejčková, M. ; Kliment, Z. ; Vlach, V. ; Vlček, Lukáš
The release of a greater amount of natural organic matter (NOM) within climate change is registered in many catchments with peatbog areas. The aim of our research is to study the dynamics of releasing dissolved organic carbon (DOC) into surface water in headwater areas with peatbogs. DOC concentrations are analysed in relation to extreme rainfall-runoff (R-R) events and according to the hydrological preconditions of the basin. These preconditions are described using selected hydroclimatic variables (14 days before the R-R event). The source data comes from stations of the Faculty of Science, Charles University, and the Czech Hydrometeorological Institute. For the evaluation of relations and processes, the Principal component analysis (PCA), hysteresis loops or Pearson correlation coefficient was used. The lag time of DOCmax for Qmax, the dependence of DOCmax and groundwater levels were studied. The influence of flow rate on the decline and ascent phases of DOC\nconcentrations by hysteresis loops and the influence of the number of partial flow maximums on the amount of transported DOC during the R-R event was analysed. Our first results show that great influence on the dynamic of DOC concentration in surface water has the change in groundwater-levels in the peatbog and the outflow amount during the R-R event. The hydroclimatic preconditions of the basin have also a significant influence on the DOC release. Changes in concentrations during R-R events also occurred for other compounds that were studied additionally. Particularly significant was the increase in metals (mainly Fe, Al, Mn) and base cation (K) and decrease in nitrate nitrogen.

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