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New flame retardants in the environment
Ezechiáš, Martin ; Cajthaml, Tomáš (advisor) ; Kočí, Vladimír (referee)
In the recent years, many research articles focused on endocrine disrupting compounds in the environment. Some of these compounds are listed in a group named brominated flame retardants. However, only few articles investigated endocrine activity of several "new" brominated flame retardants. These chemicals such as 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE) or bis(2-ethylhexyl) tetrabromophthalate (TBPH) are newly used due to ban of some previously most produced brominated flame retardant mixes. In this study, we used two recombinant yeast screens to measure estrogenic, androgenic, antiestrognic and antiandrogenic activities of some alternative brominated flame retardants. We also used ligninolytic fungi to investigate biodegradation of these compounds. Our results suggest, that 2,4,6-tribromophenol (TBP) may be a new environmental endocrine disruptor. This substance showed antiestrogenic and antiandrogenic activity in our tests. 1,2-bis(2,4,6- tribromophenoxy)ethane (BTBPE) had certain antagonistic activity too. In the biodegradation experiment, only three compounds showed significant degradation during the test period. No biodegradation have been observed for other compounds. In this study, we applied gas chromatography with mass spectrometry to analyze these "new" flame retardants. Method for gas...
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Optimization of endocrine disruptors determination in wastewater treatment plant sludge and application of the method in environmental samples.
Medková, Jaroslava ; Cajthaml, Tomáš (advisor) ; Tesařová, Eva (referee)
Hormonaly active compounds in wastewaters represent nowdays a serious problem. Proceses currently used in watewater treatment plants (WWTP) are unefficient in removing these compounds from contaminated wastewaters. The compounds are supposed to sorb onto solid sludge elements and sediments. In this work seven endocrine disruptors were detected in the sludge samples from WWTPs. A new sensitive method for detection of seven selected endocrine disruptors (4-nonylphenol, bisphenol A, estriol, 17β-estradiol, estrone, 17α- ethynylestradiol, irgasan) was developed. The method is based on accelerated solvent extraction (ASE), gel permeation chromatography (GPC) and solid phased extraction. For final extract analysis, gas chromatography coupled with mass spectrometry (GC/MS) was used. The efficiency of this method was tested using artificially contaminated sludge and the method was used to analyse real samples from several WWTPs in Czech Republic. The effect of sludge age on detection of individual analytes was assessed as well. The concentrations of endocrine disruptors measured in the samples reached up to 1 µg/g. The results are comparable or higher then those reported in other works and they show the necessity of further research on endocrine disruptors in the environment.
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Effect of zearalenone on reproductive parameters and the expression of selected genes in mice.
Dvořáková, Eva ; Pěknicová, Jana (advisor) ; Nedvídek, Josef (referee)
A number of chemicals may have a negative impact on the environment and wildlife. Endocrine disruptors (EDs), which can mimic estrogen, interfere with natural hormones in organism and can have a negative effect on the reproductive system. Such substances include zearalenone (ZEA) - mycotoxin, produced by the fungi Fusarium. Despite the non-steriodal structure of its molecule, ZEA and its derivates possess potent estrogenic activity. The influence of ZEA on reproductive parameters and changes in expression of selected genes were tested in the outbred line of mice. This study showed significant effects of ZEA on number of reproductive performances. This effect was observed at lower examined dose, to which are humans normally exposed, and at higher doses, both showed changes in the tested parameters.
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Application of ligninolytic fungi on solid substrates for degradation of endocrine disrupters
Slavíková - Amemori, Anna ; Cajthaml, Tomáš (advisor) ; Gabriel, Jiří (referee)
Today a lot of attention is focused on compounds called endocrine disrupters (EDs) among substances released to environment by humans. They are a group of substances which can disturb function of hormonal system of organisms including humans. Their poor removal at wastewater treatment plants (WwTP) were shown at various studies, thus they can reach the environment in water. A prospective way for the degradation of EDs at WwTP can be their removal by ligninolytic fungi. They are able to degrade lots of lignin-like aromatic substances because of their highly nonspecific enzymes. In this work growth and enzyme production capability of four ligninolytic fungal strains were monitored on three solid substrates (straw pellets, poplar sawdust mixed with straw pellets, oak sawdust with straw pellets), which may be suitable substrates for fungal growth in bioreactors for wastewater treatment. Ability of these enzymes to degrade EDs were tested in in-vitro degradation experiment. Trametes versicolor was found as best degrading strain with 20 μg/ml of bisphenol A, 17 α- ethynylestradiol and nonylphenol degraded below a quantification limit within 24 hours. Fungal strains degraded EDs well on all of the three substrates but wood sawdust seemed to be a better substrate for fungal growth because straw pellets...
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Hormone remedies and other endocrine disruptors within the living environment
Pfitzner, Robert ; Podlipná, Radka (advisor) ; Smrček, Stanislav (referee)
The progress of modern society has brought along the issue of environmental contamination with various chemical substances which ensue from all kinds of anthropogenous activity. Among the substances which contaminate the living environment in this way are compounds that influence the endocrine system of an organism by disrupting the physiological function of its endogenous hormones. These compunds are known as endogenous disruptors and alongside certain substances of natural origin they, too, show estrogenic activity. The exogens in question have similar structural features, such as the hormone estrogen, which is why they can interact with estrogenic receptors. The compounds are dangerous in that they can influence biological functions, despite being at very low concentrations. At present, intensive research employing the latest instrumental methods is carried out with the aim of assessing the impact of these compounds on mankind and its living environment. The aim of this bachelor's thesis is to summarise the present knowledge of the impact of endocrine disruptors on the living environment, classify them according to their source and outline the methods of analysis as well as the possibility of their decomposition with the help of biodegradation.
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The mechanisms of specific polutants impact on aquatic communities.
Vaněčková, Hana ; Fuksa, Josef (advisor) ; Hořická, Zuzana (referee)
With a decrease of classic pollution of water ecosystems the importance of PPCP (pharmaceutics and personal care products) increases. Their amount is increasing due to human consumption and thus the input into municipal wastewater and consequently into the surface water, eventually into the ground water increases as well. This bachelor work is a review of scientific literature in the field of PPCP water load. The goal is resuming the results of the studies of the influence of these substances on freshwater aquatic communities. In the beginning the sources of the variability (in time and space) of the concentrations of these substances in rivers are resumed. But the rate of affection of the aquatic communities depends even on the length of exposure, which is longterm with regard to the continuous flow of substances from wastewater treatment plants. That is why the effect of long-term incidence on aquatic communities is intensively studied. The emphasis is put on the incidence of endocrine disruptors (substances disrupting the endocrine system), which affect e.g. the oestral cycle of some kind of exposed populations. There are observed changes in the way of perception of a predator by his prey whereas the escape reactions of the prey happen to be affected. The additive effect of ixtures of...
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Functional analysis of sperm quality after endocrine disruptor treatment
Linhartová, Zuzana ; Liberda, Jiří (advisor) ; Ryšlavá, Helena (referee)
The aim The aim of my study was to determine whether the selected endocrine disruptors (EDs) affect reproductive parameters of sperm. Due to two experimental models, in which was tested the influence of selected Eds, my work is divided into two parts: A) On the boar model (Sus scrofa) was tested effect of selected EDs (zearalenone (ZEN), di(2-ethylhexyl) phthalate (DEHP), vinclozolin (VIN) on the course of capacitation, acrosome responses in vitro and changes in the detection and localization of selected proteins. B) On the fish model (Perca fluviatilis L.) was tested the influence of the selected ED- bisphenol A (BPA) on the motility and velocity of fish sperm movement. Results Mammalian model In mammalian model the course of capacitation and acrosome reaction was significantly influencing by the examined EDs in comparision with control samples. The increase of the number of marked cells during capacitation and reduce of the number of marked cells after AR compared with the differences between experimental and control samples was confirmed by the flow cytometry method. At higher concentrations EDs clearly inhibited acrosome response and thus reduce the number of sperm capable of fertilization. The relevancy of the results of detection acrosome reaction was confirmed by using various methodological...
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Influence of estrogens on mammalian sperm.
Šidlová, Adéla ; Šebková, Nataša (referee) ; Hortová, Kateřina (advisor)
For many years, estrogens have been considered typically female sex hormones. It is now certain that they are also very important in the regulation of male reproduction, whether their effect is positive or negative. Endogenous estrogens in mammalian males are an important part of the endocrine system. Estrogens play an important role in the growth and maintenance of bone mass, as well as in the development of germ cells and in the marches of spermatogenesis. Healthy sperm are essential for successful reproduction. Effect of endogenous estrogens is partly involved in the regulation of proper development of sperm. Besides the positive effect of endogenous estrogens, there is also a negative effect of estrogens from the external environment, so-called environmental estrogens. Between environmental estrogens are man-made chemicals, xenoestrogens, which increasingly contaminate the environment. Hazards of these estrogenic substances in nature is hidden in their ability to act as endocrine disruptors, which cause defects in many aspects of mammalian reproduction. With regards to the fact that there are more and more substances in current environment that can interfere with hormonal path of mammalian reproduction, it is important to look at this issue. Reproductive disorders that may be caused by...
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Ecotoxicity tests on cellular level
Procházková, Petra ; Vávrová, Milada (referee) ; Zlámalová Gargošová, Helena (advisor)
Endocrine disrupting compounds among significant environmental pollutants. They are dangerous both for humans and other organisms by affect their hormonal system. They enter the environment during production, use and disposal some chemicals, but they may be of natural origin. The aim of this work is to give a brief overview of possible methods of determination of the presence of ecotoxic substances in the environment, using the in vitro toxicity assays. These tests use cell cultures instead of test organisms. The work describes principles of ecotoxicity tests at the cellular level, such as cell viability assays, cell proliferation assays, assays based on the metabolic activity of cells or DNA microarrays. A significant part of this work is focused on the possibilities of determination of endocrine disruptors by selected assays. They are ligand binding assays, reporter gene assays (recombinant yeast assay, mammalian-based reporter gene assays) and cell proliferation assay called E-screen. Significance and rationale use of tests to prove the endocrine activities in environmental matrice is given through examples of studies in which the tests were used.
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