Dissertations / Theses: 'Estrogenic endocrine disruptors'

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Swart, Johannes Cornelius. "The development and implementation of biomarker assays for estrogenic endocrine disruptors." Thesis, University of the Western Cape, 2008. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_6792_1258011445.

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'Endocrine disrupting chemicals (EDCs) are compounds found in the environment that have the potential to disrupt normal endocrine function. Estrogenic EDCs (e-EDCs) is a subclass of EDCs and is defined as substances contaminating the environment that may mimic or inhibit the effect of endogenous estrogen and therefore may influence developmental and reproductive health in humans and animals. The aim of this study was to develop, validate and implement a battery of in vitro and in vivo screening assays for e-EDCs. The study was concluded by implementing this battery of assays to assess the Eerste River, South Africa at three sampling sites, namely Jonkershoek, Stellenbosch sewage treatment works (STW) effluent and Spier for e-EDCs. The control site, Jonkershoek contained very low levels of estrone. Water from this site showed no estrogenic activity when the E-screen and the ER_ induction in MCF-7 cells. Some of the water samples collected at this site tested positive for estrogenicity when analysed with the juvenile tilapia VTG assay, whereas the rest were negative. The estrone levels in the sewage effluent extracts as well as Spier were significantly higher. The assay using ER_ protein induction by the MCF-7 cell line, the MCF-7 proliferation assay and the tilapia in vivo screen for estrogenicity showed that these samples are estrogenic. Results obtained for estrogenicity at the three different sampling sites for each of the assays in the battery were comparable. In this study we developed, validated and also implemented a battery of assays encompassing both in vitro and in vivo assays, based on different biological mechanisms, to detect estrogenic EDCs. To our knowledge, this is the first study that has used a battery of bioassays to specifically assess a South Africa river for estrogenicity...'

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Al-Jandal, Noura. "The effects of estrogenic endocrine disruptors on the osmoregulatory functions in euryhaline fish." Thesis, University of Exeter, 2011. http://hdl.handle.net/10036/3131.

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Osmoregulation is an essential process to maintain water and ionic balance and when euryhaline fish move between freshwater and seawater environments as part of their life cycle this presents additional osmoregulatory challenges. Migrating fish can be exposed in both environments to pollutants such as endocrine disrupting chemicals (EDCs) that include natural hormones (e.g. 17β-estradiol; E2), synthetic hormones (e.g. 17α-ethinylestradiol; EE2), and industrial chemicals (e.g. nonylphenol). The focus of this thesis was to study the effects of different categories of EDCs on the osmoregulatory functions of euryhaline fish such as three-spined sticklebacks (Gasterosteus aculeatus) and rainbow trout (Oncorhynchus mykiss). Osmoregulatory variables (such as osmolality, water and ionic content) were compared in plasma and tissues (white muscle and carcass) of rainbow trout. This validated the use of specific tissue parameters as a surrogate of plasma responses to various osmoregulatory challenges. Waterborne exposure to 17α-ethinylestradiol revealed differential sensitivity of vitellogenesis in the three-spined sticklebacks (no induction) and rainbow trout, but had a significant effect on calcium homeostasis in both species. Intraperitoneal implants of 17β-estradiol reduced CaCO3 production and apparent water absorption in the intestine and increased in tissue calcium stores of seawater-acclimated trout, but fish were able to compensate and showed no overall osmoregulatory disturbance. Waterborne exposure to nonylphenol in freshwater trout was also investigated, but no effects on osmoregulation were found up to 2 ng/l. Overall, estrogens can affect osmoregulation differentially in euryhaline fish species, and sometimes at EDC levels lower than the threshold for reproductive effects (i.e. vitellogenin induction).

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Teske, Sondra Sue Gery. "Aspects of Measuring Mass Balances of Endocrine Disrupting Compounds through Wastewater Treatment." Diss., The University of Arizona, 2009. http://hdl.handle.net/10150/194944.

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Ecological impacts of natural estrogens and xenoestrogens in treated wastewater include altered sexual development and sex ratios among continuously exposed organisms. The primary sources of estrogenic activity in wastewater are natural estrogens such as estrone, 17β-estradiol and estriol and synthetic compounds like 17α- ethinylestradiol, alkylphenols and alklphenol ethoxylates. Precursors in raw wastewater can yield estrogenic intermediates during wastewater treatment. All these compounds can be destroyed by biochemical processes conventional wastewater treatment processes, suggesting that conventional processes can be optimized for removal of estrogenic activity from wastewater. Sorption to sludges derived from wastewater treatment affects the fates of hydrophobic xenoestrogens such as nonylphenol, in part because the biodegradability of sorbed contaminants is limited. It may also be possible to tailor sludge stabilization processes to remove trace contaminants, including estrogens. For example, there are significant differences in the efficiencies of aerobic and anaerobic digestion for destruction of alkylphenols and probably other estrogenic compounds with aromatic moieties. Because advanced wastewater treatment is not economically feasible for most communities, there is ample incentive to develop accurate relationships between operational parameters and removal of estrogenic compounds during secondary wastewater treatment. Large quantities of polybrominated diphenyl ethers (PBDEs) have been used as flame retardants in clothing and plastic products since the 1970s. A small fraction of the PBDEs in manufactured products subsequently enters municipal wastewater. The resistance of these compounds to chemical and biochemical transformations provides opportunities for accumulation in sediments. Balances developed for PBDE congeners indicate that conventional wastewater treatment processes and soil infiltration of treated wastewater in recharge operations do not discriminate significantly among the major congeners in commercially available PBDE products. Accumulation of PBDEs at near part-per-million levels was measured in the sediments at the Sweetwater Recharge Facility in Tucson, Arizona, during 10-15 years of operation. Half times for loss of major PBDE congeners from sediments were decades or longer. Local agricultural soils amended with biosolids over a 20-year period showed similar accumulation of PBDEs. The widespread use of PBDEs in commercial products, compound persistence and toxicity indicate that additional effort is warranted to better understand fate-determining processes for PBDEs in the environment.

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Blavier, Julie. "Degradation of estrogenic endocrine disruptors by laccases: from estrogenicity monitoring methods to reactor design." Doctoral thesis, Universite Libre de Bruxelles, 2015. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/222520.

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In the past decades, much concern has been expressed regarding organic micropollutants generating endocrine disruption. In particular, estrogenic endocrine disruptors, compounds that interfere with the estrogenic hormonal mechanisms, are in the center of environmental scien- tists attention. Numerous endocrine disrupting effects have been observed at concentrations corresponding to those found in aquatic environments, such as feminization of fauna, infertility, reproductive disturbance, cancer, or developmental disruption. Wastewater treatment plants ef- fluents have been identified as the main source of estrogenic endocrine disruptors in the aquatic environment, due to inappropriate treatment. Promising alternative treatment systems based on the use of ligninolytic enzymes (e.g. laccases) have recently emerged. This work falls within the framework of these new techniques. Althoughno environmentally safe threshold can clearly be set, focusing on the removal of global estrogenicity in water instead of concentrations of targeted estrogenic compounds seems a relevant research. To our knowledge, the use of these recently emerged enzymatic processes at an industrial scale (such as for the treatment of urban wastewater), oriented towards water overall estrogenicity, has not been implemented yet.The general objective of this work was to develop ans study a process of removal of estro- genicity by laccases from white-rot fungi, in laboratory, with the purpose of design and scale-up for industrial implementation. This work consisted of the conception, characterization, testing, study and modeling of this process.First, in order to enable the study and the scaling-up of a process of estrogenicity removal, op- timizing the technologies of quantification of estrogenicity in water was a real necessity. Therefore, a study of the methods of estrogenicity monitoring, within a treatment process framework, was conducted. Based on a wide literature review, existing methods were gathered and assessed with the aim of their use as monitoring and design tools. Fromthat review, four methods were selected and tested according to numerous criteria and their compatibility with our process: three bioassays (Yeast Estrogen Screen assay; Lyticase-assisted Yeast Estrogen Screen assay; MCF-7 cell based reporter gene assay) and one analytical method (High Performance Liquid Chromatography with UV detection, HPLC-UV). Concentration-response curves towards the reference 17β-estradiol, in several solvents, were acquired. A fitting model was developed for further expression of all measurements in Estradiol Equivalents. The methods were used to evaluate the estrogenicity of bisphenol A, triclosan and nonylphenol, along with estrogenicity of mixtures of bisphenol A and 17β-estradiol. The testing of these four methods enabled the assessment of their sensitivity, re- producibility, and implementation. Based on that experimental assessment, the Lyticase-assisted Yeast Estrogen Screen (LYES) assay was selected and systematized to be further applied, in combination with an adapted protocol of HPLC-UV analysis, to the monitoring of estrogenicity removal in two lab-scaled reactors. The LYES assay demonstrated a real methodological potential for thescale-up of an estrogenicity removal process and could be used as a design tool. For both reactors, results have indicated that HPLC-UV and LYES assay methods are completely inter- changeable in the case of bisphenol A monitoring (in the conditions used in this work). This work also highlighted the peculiar behavior of mixtures of bisphenol A and 17β-estradiol in terms of estrogenicity, and the parallel observation of an enhancement of bisphenol A estrogenicity removalin presence of 17β-estradiol.In the second part of this work, a batch reactor with laccases in solubilized form was developed and estrogenicity removal was assessed. Kinetics data for the degradation of estrogenic endocrinedisruptors were acquired with the LYES assay (estrogenicity) and the HPLC-UV method (concen- trations). Degradations were performed from several solutions of bisphenol A, 17β-estradiol, and mixtures. In the case of 17β-estradiol and mixtures, conversions reached minimum 90% within 1 hour of degradation at our conditions, with no dependency on pollutant initial concentrations. In the case of bisphenol A, conversions varied from 0 to 100% after 6 hours of degradation and were shown tobe strongly dependent on BPA initial concentrations, indicating the laccases deac- tivation by substrate. Bisphenol A byproducts of degradation were also analyzed, which indicated their absence of estrogenicity and their potential linear evolution with BPA degradation. Acquired kinetics data were exploited for the modeling of the batch degradations kinetics. At this stage of the work, no clear kinetics conclusions could be made in this part.From an industrial point of view, the use of immobilized enzymes is more cost-effective, due to the improvement of enzymes recovery and stability. Therefore, in the third part of this work, a continuous column-shaped packed-bed reactor composed of laccases immobilized on a silica support was developed. The packed-bed reactor was built and tested in laboratory. Residence time distributions, pressure drop calculations, and tracer degradations were performed on the re- actor for its characterization.Immobilization and activity measurements protocols were applied. Similar monitoring than in the batch reactor (LYES assay and HPLC-UV) were performed during continuous degradations of bisphenol A, 17β-estradiol, and mixtures in the packed-bed reactor. Acquired kinetics data were exploited to study and model the kinetics occurring in the packed-bed reactor. Mass transfer phenomena and laccases deactivation by substrate in the reactors were investigated and modeled, revealing, depending on the pollutant, the presence of slight external mass transfer limitation and the strong dependence of the kinetics on laccases deactivation. A design tool, in the form of a mathematical model for the design of a packed-bed reactor with immobilized laccases for the degradation of bisphenol A and related estrogenicity, was developed. The model was validated (simple validation) on experimental data. The model was then used, as a comparison, for the design of a reactor with similar conditions than a documented technique of bisphenol A degradation by ozone. The design resulted in a reactor twice smaller than for degradation by ozone, for the same conversion.In the current context of environmental crisis, this work proposed a first version of a promising practical solution for the treatment of environmentally problematic e-EDCs, oriented towards water overall estrogenicity monitoring and removal, and using natural biocatalysts.
Doctorat en Sciences de l'ingénieur
info:eu-repo/semantics/nonPublished

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Le, Fol Vincent. "Approche in vivo/in vitro du métabolisme de perturbateurs endocriniens chez le poisson zèbre (Danio rerio)." Phd thesis, Toulouse, INPT, 2015. http://oatao.univ-toulouse.fr/15125/1/lefol_1.pdf.

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Les perturbateurs endocriniens (PE) posent des risques pour la santé Humaine et pour la faune. L’utilisation de tests biologiques basés sur des mécanismes d’action spécifiques permet de caractériser le potentiel PE des substances chimiques dans le cadre de l'évaluation toxicologique, mais les capacités de biotransformation de ces modèles sont rarement prises en compte. Or, le métabolisme conditionne le devenir des xénobiotiques (détoxication vs. bioactivation) et donc in fine l'activité biologique mesurée. Dans ce travail, le devenir de deux contaminants œstrogéniques émergents (benzophénone-2, bisphénol S) a été comparé dans de nouveaux modèles in vitro et in vivo de poisson zèbre (cellules ZELH-zfERs, larve transgénique cyp19a1b-GFP) et des lignées humaines. Nos résultats démontrent que les modèles de poissons zèbres sont métaboliquement compétents et soulignent leur pertinence dans une approche intégrée in vivo/in vitro pour le criblage de l'activité PE des substances chimiques.

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Cox, Brian Joseph. "Development of an assay for estrogenic endocrine disrupters involving the rat liver estrogen receptor alpha." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ31820.pdf.

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Wu, Fei. "Comparative activation of estrogen receptor alpha (er alpha) by endocrine disruptors." [College Station, Tex. : Texas A&M University, 2007. http://hdl.handle.net/1969.1/ETD-TAMU-2433.

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Zhao, Zunyang. "Removal of Estrogens at Full and Pilot Scale Livestock Manure Treatment Systems." Diss., Virginia Tech, 2008. http://hdl.handle.net/10919/26067.

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Three experiments were conducted to 1) develop appropriate methods for livestock manure estrogen analysis; 2) determine estrogen removal in different manure treatment systems; and 3) determine estrogen removal from dairy manure in pilot scale reactors. In Experiment I, the recoveries of 17Ã -estradiol (E2) and estriol (E3) were evaluated in double distilled water and dairy manure after a base extraction and analysis of estrogens by enzyme-linked immunoassay (ELISA) and yeast estrogen screen (YES) assay. The recoveries of E2 were 104% (ELISA) and 97% (YES) in double distilled water. 112% of E2 and 79% of E3 in flushed dairy manure and 118% of E2 in anaerobic digester effluent were recovered with ELISA. 67% and 140% of E2 in flushed manure and anaerobic digester effluent, respectively, were recovered with YES assay. In Experiment II, samples were collected from a full-scale manure handling system incorporating separation and aeration (Separation/Aeration), an anaerobic digester receiving dairy manure (Anaerobic Digester), and four conventional dairy and swine manure storages. 70% of E2 (230 vs. 769 Î¼g/cow/day) and 86% of E3 (78 vs. 552 Î¼g/cow/day) mass were removed from the Separation/Aeration system when the effluent was compared to the influent; the ratio of E2 to total estrogenicity (E2-eq) averaged 76%. In the Anaerobic Digester, 38% of E2 (592 vs. 954 Î¼g/cow/day) and 30% of E3 (338 vs. 483 Î¼g/cow/day) mass were removed; E2 contributed more to E2-eq in the influent than in the effluent (43 vs. 26%). There was no significant difference for E2-eq (431 vs. 284 ng/g of total solids) and E2 (248 vs. 73 ng/g of total solids) concentrations between barn and pti in conventional dairy manure storages; E2 contributed more to E2-eq in barn manure than in pit manure (54 vs. 30%). In swine manure storages, both E2-eq (2852 vs. 1551 vs. 148 ng/g of total solids) and E2 (1933 vs. 808 vs. 89 ng/g of total solids) concentrations decreased (barn vs. primary lagoon vs. secondary lagoon; no significance analysis); the change of E2 ratio to E2-eq was not consistent between barn and lagoon manures between farms. In Experiment III, samples were collected from six pilot scale reactors: two aerated reactors (60% and 100% aeration; AER60 and AER 100), a nitrifying/denitrifying reactor (NDN), an enhanced biological phosphorus removal reactor (EBPR), an anaerobic digester (AD), and a nitrifying reactor (NI) following AD. The influent had higher mass of E2 and E2-eq than the effluent with all reactors. Estrogen removal efficiencies were expressed in two ways: % and %/aerobic hour (or hour) of the influent mass. Higher ammonia nitrogen removing reactors had higher E2 and E2-eq removal in %, higher E2 removal in %/aerobic hour, and the same E2-eq removal in %/aerobic hour compared to those with lower ammonia nitrogen removal. Estrogen removal efficiencies (both in % and %/aerobic hour) were similar in nitrifying and denitrifying reactors. Reactors with aeration supported greater estrogen removal than those without. Reactors with influent anaerobic digestion pretreatment had the same E2 and E2-eq removal in % but higher E2 and E2-eq removal in %/aerobic hour compared to those without. In conclusion, the aerobic treatment system removed more estrogens than the anaerobic one, which means aerobic conditions support more estrogen degradation than anaerobic conditions. The change of the ratios of E2 to E2-eq varied in different livestock manure treatment systems, which reflected different removal rates of E2 and other estrogenic compounds. The pilot scale reactors significantly removed E2 and E2-eq in dairy manure. Ammonia nitrogen removal rates and aeration are the two main factors influencing E2 and E2-eq removal.
Ph. D.

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Kwekel, Joshua Caleb. "Cross-species comparison of estrogenic endocrine disruptor-induced, uterotrophic gene expression in the rodent." Diss., Connect to online resource - MSU authorized users, 2008.

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Shimada, Kiyoshi, Yonju Ha, Akira Tsukada, Noboru Saito, Shinobu Maekawa, Makoto Nishizuka, and Masayoshi Imagawa. "In vivo and in vitro screening of endocrine disrupting chemicals with estrogenic activity in Japanese quail." Science Reviews 2000 Ltd, 2005. http://hdl.handle.net/2237/9265.

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Chen, Gunilla. "Changes in adipose tissue mRNA expression due to perinatal exposure to bisphenol A in rats." Thesis, Uppsala universitet, Institutionen för kvinnors och barns hälsa, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-235115.

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Bisphenol A (BPA) is an estrogen receptor binding chemical, widely used in the plastics industry, and as such commonly encountered from plastic containers etc. Even at very low doses, BPA is believed to induce obesity and to have various endocrine disruptive effects. The purpose of this study was to determine possible gene expression changes in gonadal and inguinal adipose tissue from rats perinatally exposed to BPA. The method used was quantitative real-time PCR, and genes found to be up-regulated were PLZF, adiponectin, RXRa and Tcf21, while down-regulated genes were PPARγ, Tmem26, EsR1, Resistin, LPL, Chemerin, Serpina6, TFAM and Ahr. This is so far largely unsupported by other studies, and more research is needed.

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Coufal, Kendra. "A profile of oestrogrens and a survey of endocrine disrupters in marine turtles of Australia and Malaysia /." St. Lucia, Qld, 1998. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe16547.pdf.

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Olowu, Rasaq Adewale. "Impedimetric and electrode kinetic dynamics of DNA aptamer nanobiosensors for estrogeneous endocrine disruptors." University of the Western Cape, 2011. http://hdl.handle.net/11394/8455.

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Philosophiae Doctor - PhD
In this work, DNA aptamer biosensor systems were developed for the detection of l7p-estradiol - an estrogeneous endocrine disrupting chemical (EDC). Endocrine disrupting chemicals are group of compounds that impact negatively on the endocrine system of humans and wildlife. High concentrations of l7p-estradiol in water or food chain disrupts the physiology of the endocrine system of various animal species, leading to feminisation in fish and stimulates the proliferation of cancer cells in humans. Aptasensor systems for the determination of l7pestradiol were prepared with three immobilization platforms: (i) poly(3,4- ethylenedioxythiophene) {PEDOT} doped with gold nanoparticles (AuNPs) to form PEDOTIAuNPs polymeric nanocomposite, (ii) generation 1 poly(propylene thiophenoimine)-copoly( 3 ,4-ethy lenedioxythiophene) dendritic star copolymer (G 1PPT -co-PEDOT), and (iii) generation 2 poly (propylene thiophenoimine)-co-poly(3,4-ethylenedioxythiophene) dendritic star copolymer (G2PPT-co-PEDOT). The morphological properties of the sensor platforms were interrogated by scanning emission microscopy (SEM) and atomic force microscopy (AFM), while their spectroscopic characteristics were studied by Fourier transform infra red spectroscopy (FTIR) and fluorescence spectroscopy. The electrochemical behaviour of the platforms and the aptasensors were studied by electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV) and square wave voltammetry (SWV). The DNA aptamer developed for detecting 17~-estradiol and which was used in the fabrication of all aptamer biosensors in this study is a 76-mer biotinylated aptamer (5'-BiotinGCTTCCAGCTTATTGAATTACACGCAGAGG TAGCGGCTCTGCGCATTCAATGCTGCGCGCTGAAGCGCGGAAGC-3'). AulPEDOTIAuNPslAptamer (platform 1) was obtained by covalently attaching streptavidin to the polymeric nanocomposite platform using carbodiimide chemistry and the aptamer immobilized via streptavidin-biotin interaction. The electrochemical signal generated from the aptamer-target molecule interaction was monitored electrochemically using cyclic voltammetry and square wave voltammetry in the presence of [Fe(CN)6J 3-/4- as a redox probe. The signal current observed was inversely proportional to the concentration of 17Bestradiol. The aptasensor demonstrated specificity toward 17~-estradiol. The detectable concentration range of the 17B estradiol was 0.01 nM-O .09 nM with a detection limit of 3.2 pM. The 76-mer biotinylated aptamer for 17~-estradiol was incorporated into a generation 1 poly(propylenethiophenoimine )-co-poly(3 ,4-ethylenedioxythiophene) dendritic star copolymer modified Au electrode via biotin-avidin interaction (platform 2). The Bode plot shows that the charge transfer dynamics of the nanoelectrode can be frequency modulated while the AulG 1PPTco- PEDOT nanoelectrode exhibited greater semi-conductor behavior (higher phase angle value) than AulG 1PPT due to the incorporation of charged functionalized dendrimer at low frequencies (100 mHz). The biosensor response to 17~-estradiol was based on the decrease in the SWV current as the EDC binds to the ssDNA aptamer on the biosensor. The dynamic linear range of the sensor was 0.01-0.07 nM with a detection limit of7.27 pM. Synthesis of electro synthetic generation G2PPT-co-PEDOT (platform 3) was performed by copolymerization of PEDOT with G2PPT dendrimer modified electrode immersed in a solution of 0.1 M LiCI04 containing 0.1 M EDOT monomer and 0.1 M sodium dodecyl sulphate (SDS) for ten (10) cycles. The electrochemical behaviour of the dendritic star copolymer was investigated with CV and EIS in LiCI04 and phosphate buffer solutions. The results show that the electrochemical deposition of G2PPT-co-PEDOT on gold electrode decreased the electrochemical charge transfer resistance when compared to AuiPEDOTILiCI04 and AuiLiCI04 interfaces. Bode impedimetric analysis indicates that G2PPT-co-PEDOT is a semiconductor. The fabrication of two novel aptasensors (based on platforms 2 and 3) simultaneously on a screen printed micro array electrode of 96-well multichannel electrochemical robotic sensor testing system for the detection of endocrine disrupting l7~-estradiol, was also carried out. The aptasensors responses to l7~-estradiol, based on the decrease in the SWV current, were evaluated.

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Holbrook, Richard David Jr. "Fate and Transport of Endocrine Disrupting Compounds during Wastewater Treatment: The Role of Colloidal and Particulate Material." Diss., Virginia Tech, 2003. http://hdl.handle.net/10919/28853.

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The presence of biologically-active estrogenic endocrine disrupting compounds (EDCs) in treated effluents from biological wastewater treatment facilities has prompted wide-spread interest in the behavior of these contaminants during the activated sludge process. The yeast-estrogen screen (YES) was used to quantify the estrogenic activity of samples taken from different areas of three wastewater treatment facilities. An estrogenic mass-balance around these facilities revealed that the majority of influent estrogenic activity was removed in the activated sludge process, but the main route for EDC discharge to the natural environment was via the treated effluent. The estrogenic activity in the effluent from a membrane bioreactor (MBR) was lower compared to a fully aerobic activated sludge process using secondary clarification, suggesting that enhanced removal of particulate and colloidal material may improve EDC removal efficiency. Colloidal material was obtained from settled mixed liquor suspended solids (MLSS) collected from a pilot MBR and a full-scale activated sludge process that included anoxic and aerobic zones. The MLSS was sized fractionated by filtration, and used to quantify the sorption coefficients for pyrene, 17β-estradiol (E2), and 17α-ethinylestradiol (EE2) by fluorescence quenching. The MLSS-derived colloidal organic carbon (COC) sorption coefficient (Kcoc) for pyrene ranged from (< 1 to 80) L/kgcoc, indicating a similar affinity for pyrene compared to natural organic matter. Kcoc coefficients for E2 ranged between (< 1 to 158) L/kgcoc for E2 and (< 1 to 228) L/kgcoc for EE2, and are the highest E2 and EE2 sorption coefficients reported in the literature to date. There was a strong correlation between the Kcoc coefficients and molar extinction coefficient at 280 nm (e280) for pyrene and E2, suggesting that the interaction of the π;-electrons is an important factor in determining overall sorption behavior. There was no such correlation for EE2. Based on the Kcoc coefficients and COC concentrations of the samples, between 1 and 50% of the aqueous E2 and EE2 concentrations were associated with colloidal material. In a novel application of the YES bioassay, the bioavailability of colloid-associated E2 was quantified by comparing the EC50 values of the dose-response curves generated in the presence and absence of size fractionated COC. An increase in EC50 values as a function of COC concentration was attributed to a reduction in bioavailability of E2, suggesting that MLSS-derived COC can reduce, but not eliminate, the biological impact of EDCs. However, there was a high degree of variability in the EC50 values, and estimates of the colloid-associated E2 fraction based on the Kcoc-e280 correlation were unsuccessful in accurately predicting increases in EC50 values. Nevertheless, the YES bioassay may represent a powerful tool in determining the bioavailability of EDCs in complex environmental samples. Results from this research effort suggest that the colloidal phase derived from activated sludge systems represents an important transport vehicle whereby EDCs and other trace organic compounds can enter into the natural environment. Consequently, wastewater treatment plants discharging to sensitive ecosystems or involved with direct water reuse programs should optimize the treatment process to remove colloidal material.
Ph. D.

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Bousoumah, Radia. "Le challenge de l’analyse multi-résidus de perturbateurs endocriniens à activité estrogénique dans les fluides et tissus biologiques humains : Choix de stratégies de préparation des échantillons et de mesure par spectrométrie de masse." Electronic Thesis or Diss., Paris, AgroParisTech, 2015. http://www.theses.fr/2015AGPT0028.

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Depuis plus d’une vingtaine d’années, la problématique des perturbateurs endocriniens (PE) mobilise la communauté scientifique et les pouvoirs publics en raison des effets néfastes, avérés ou suspectés, de ces composés sur la santé de l’Homme. En particulier, la génération de données d’exposition interne (imprégnation) chez certaines sous-populations reconnues ou supposées plus sensibles (femmes enceintes, foetus, nourrissons) est à la fois une priorité et un domaine exigeant associé à une certaine rareté. De par leur diversité au plan structural et en termes de propriétés physico-chimiques, l’analyse simultanée d’un large panel de PE reste de nos jours un véritable challenge analytique. Dans ce contexte, l’objectif de ce travail consistait à développer une méthode multi-résidus permettant l’isolement et la mesure simultanée de PE à effet estrogénique (13 PE au total). En premier lieu, une méthode de mesure par couplage chromatographie en phase liquide-spectrométrie de masse en tandem (UPLC-MS/MS) après dérivation chimique par le chlorure de dansyle a été développée. En second lieu, un support de type polymère à empreinte moléculaire (MIP phénolique) a été mis en oeuvre pour l’extraction simultanée du panel de PE ciblés à partir du milieu aqueux et de matrices biologiques de complexité croissante (urine, sérum, lait maternel). La stratégie développée sur MIP phénolique a été appliquée, après prévalidation, à un ensemble d’échantillons de sérum maternel, sérum du cordon et urine de nouveaux-nés. Enfin, un support de type colonne greffée par du récepteur aux estrogènes α (colonne ERα) a été appliqué pour l’isolement simultané des composés ciblés à partir d’un milieu aqueux
For over twenty years, the issue of endocrine disruptors (EDs) mobilizes the scientific community and public authorities because of the negative effects, actual or suspected, of these compounds on human health. In particular, the generation of internal exposure data (impregnation) in some subpopulations, which are recognized or assumed as being sensitive (pregnant women, fetuses, infants), is both a priority and a demanding field associated with a certain rarity. Considering their structural diversity and with regards to their physicochemical properties, the simultaneous analysis of a large panel of EDs remains a real analytical challenge. In this context, the objective of this work was to develop a multi-residue method for the simultaneous isolation and measurement of estrogenic endocrine disruptors (13 EDs in total). Firstly, an analysis method using liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS) after chemical derivatisation by dansyl chloride was developed. Secondly, a molecularly imprinted polymer (MIP with phenolic imprint) was implemented for the simultaneous extraction of the targeted EDs from aqueous medium and biological matrices of increasing complexity (urine, serum, breast milk). The strategy developed on MIP was applied, after validation, to a set of samples (maternal serum, cord serum and urine of newborns). Finally, a column support grafted with estrogen receptor α (ERα column) was applied for the simultaneous isolation of the targeted compounds from an aqueous medium

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Yiu, Kwok Wing. "Measuring the binding between estrogen receptor alpha and potential endocrine disruptors by fluorescence polarization and total internal reflection fluorescence." HKBU Institutional Repository, 2013. http://repository.hkbu.edu.hk/etd_ra/1503.

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Mehrotra, Mamta. "Characterisation of electrochemical detection of oestrogen by using yeast oestrogen binding protein." Thesis, University of Canterbury. School of Biological Sciences, 2015. http://hdl.handle.net/10092/10223.

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Oestrogens are female sex hormones. Both natural and synthetic oestrogens have been found in many aquatic environments. There are three naturally occurring oestrogens – oestradiol, estriol and estrone. Oestradiol (correctly known as 17β oestradiol or E2) is a naturally occurring steroid hormone and is the most potent of these three. Diethylstilbestrol, dienestrol, quinestrol etc are synthetic oestrogens. These environmental steroidal and nonsteroidal oestrogens act as endocrine disruptors (EDs). Both types of oestrogens in the environmental samples can be quantified using several laboratory methods such as high pressure liquid chromatography (HPLC), gel permeation chromatography (GPC) etc. but they often require extensive training to perform. Arxula adeninivorans is biotechnologically significant dimorphic yeast with unusual characteristics. It can use a wide range of substrates and it is thermotolerant, osmotolerant and halotolerant. It is a non-pathogenic fungus and is therefore ideal for use in industrial settings. It is a source of many enzymes and a wide range of transformation platforms have been developed to enable the production of foreign proteins. In this project, A.adeninivorans was transformed with histidine-tagged synthetic oestrogen binding protein (EBP) gene based on the Candida albicans EBP sequence. The recombinant EBP expressed in the yeast Arxula is separated using HisTrap columns. Linear sweep voltammetry was used for the detection of EBP redox responses to oestrogen in solution. A three-electrode configuration was used for all measurements [auxiliary electrode (platinum wire), reference electrode (Ag/AgCl) and working electrodes (Pt 50μm diameter micro-disc and 2 mm diameter glassy carbon)]. Electron transfer from EBP to electrodes will require the use of a mediator system and TMPD, a lipophilic mediator used in this experiment. Screen printed electrodes (SPEs) were used to detect the interaction between EBP and oestrogen. To perform experiment with SPE, EBP was immobilized on SPE using the crosslinker glutaraldehyde. Differential pulse voltammetry (DPV) was used to detect interactions of EBP and oestrogen on SPE. Immobilion N transfer membrane was impregnated with TMPD solution and electrochemistry (DPV) was performed. The purpose of using membrane is to simulate the immobilization of TMPD on SPE along with EBP for the detection of oestrogen.

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Siegel, Jan. "Matematické modelování systému reverzní osmózy pro detekci estrogenů ve vodě." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2017. http://www.nusl.cz/ntk/nusl-316845.

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Estrogen compounds are a subgroup of the environmental pollutants named Endocrine Disrupting Chemicals. It is a large group of chemicals which are capable of causing hormonal imbalance of an organism and affecting its reproductive, developmental or behavioral functions. In the environment, they are found in very low concentrations (below ng/l). This makes their detection and elimination highly problematic. The Research Centre for Toxic Compounds in the Environment (RECETOX) has been developing an experimental device which employes reverse osmosis (RO) to concentrate the trace amounts of micropollutants (e.g. estrogens). The aim is to lower the detection limit of subsequent analytical methods. RO seems to be a promising alternative to commonly used methods which are more time consuming and costly. The aim of this thesis is to create a mathematical model of RO, which would describe the process of estrogen concentration and therefore could contribute to the optimization of experimental device. The mathematical model was created in MATLAB-simulink and verified by comparison to thirteen experimental results. The solutions used to test the model were NaCl at 0.002–2 g/l and drinking water with 17-ethinylestradiol of 25 ng/l. In order to concentrate the retentate on a flat-sheet RO membrane the model achieves a mean relative error in the range of 0.9–4.9 % for NaCl and drinking water. For the concentration of estrogens the deflection is 3.6 %. Comparing the model and experimental concentration of NaCl on a spiral wound RO-membrane, the deviation is in the range of 5.9–8.7 %. So far, ratio of retentate volume from the beginning to the end of the process has been used to determine the process recovery. However, due to the results obtained in the thesis, this approach appears inaccurate. A more accurate recovery would likely be achieved by using the theoretical concentration value obtained by the proposed mathematical model. However, to increase reliability, the further measurements with estrogens are needed, and also to determine the causes of deflection of model and experimental retentate volume values at the end of the concentration

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19

Tan, Benjamin L. L. "Chemical and Biological Analyses of Selected Endocrine Disruptors in Wastewater Treatment Plants in South East Queensland, Australia." Thesis, Griffith University, 2007. http://hdl.handle.net/10072/365603.

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Studies in North America, Europe, Japan and Australia have reported the presence of endocrine disrupting compounds (EDCs) in wastewater treatment plants (WWTPs) effluent could affect physiological and reproductive function in exposed fish consistent with exposure to hormonally active chemicals. The occurrence of EDCs in rivers and receiving environments situated near WWTPs raises concern over the removal efficacy of these compounds by conventional treatment processes. The main aim of this study was to utilize chemical analyses to assess concentrations of selected endocrine disruptors as well as a biological assay to measure the potential estrogenic effects of EDCs present in water discharged from wastewater treatment plants in South East Queensland, Australia. Currently, there are few reported studies on the estrogenic effects of EDCs released from WWTPs into receiving environments in Australia. Two field sampling methods were used. Grab sampling with subsequent extraction using a solid-phase extraction (SPE) technique and passive sampling utilizing EmporeTM (styrene-divinylbenzene copolymer) disk were used in this study. A gas chromatography-mass spectrometric (GC-MS) method was successfully developed to simultaneously analyze 15 environmentally ubiquitous EDCs including phthalates, alkylphenols, tamoxifen, androgens and estrogens. Application of these methods for the determination of target EDCs in wastewater samples in this study showed 80 – 99% removal of most EDCs from influent to effluent, despite the wastewater treatment plants having different treatment processes. It was observed that the passive samplers accumulated less EDCs than predicted when compared to the grab samples. This is probably caused by, but may not be limited to, biofouling, low flow rate, biodegradation and temperature which can progressively reduce the uptake of compounds into the sampler. A future challenge would be to improve the reliability of passive samplers by reducing or controlling the environmental conditions that may impact on the passive sampler performance. Stir bar sorptive extraction (SBSE) in combination with thermal desorption coupled to GC-MS was successfully applied to analyze a range of EDCs in wastewater, biosolids and sludge. The technique was shown to be very versatile, shortening extraction time, reducing sample volume needed as well as being sensitive for the analysis of a wide range of EDCs. The results showed that there were high amounts of phthalates, alkylphenols and female hormones present in the raw influent wastewater and biosolids of the WWTP samples. For the complimentary bioassay, a proliferation assay using human breast cancer cell line MCF-7 (E-Screen assay) was used to determine estrogen equivalents (EEqs) in grab and passive samples from five municipal WWTPs. EEq concentrations derived by E-Screen assays for the grab samples were between 108 – 356 ng/L for the influents and <1 – 14.8 ng/L for the effluents with the exception of one effluent sample which was at 67.8 ng/L EEq. In most wastewater samples, the natural estrogens contributed to 60% or more of the EEq value. Based on the chemical and in vitro biological analyses results and coupled with reported no observed effect concentration (NOEC) in vivo studies (mainly based on fish vitellogenin studies), the risk of EDCs found in effluents of the monitored WWTPs having a significant impact on the receiving environment is reasonably low. Furthermore, a fugacity-based analysis was employed to model the fate of selected industrial chemicals with endocrine disrupting properties in a conventional activated sludge WWTP. Using mass balance principles, a fugacity model was developed for correlating and predicting the steady state-phase concentrations, the process stream fluxes, and the fate of four phthalates and four alkylphenols in a WWTP. The relative amounts of chemicals that are likely to be volatilized, sorbed to sludge, biotransformed, and discharged in the effluent water was assessed. Results obtained by applying the model for the eight compounds compared satisfactorily with data from the WWTP. All eight EDCs modelled in this study had high removal efficacy from the WWTP. Apart from benzyl butyl phthalate and bisphenol A, the majority is removed via biotransformation followed by a lesser proportion removed through primary sludge. Fugacity analysis provides useful insight into compound fate in a WWTP and with further calibration and validation the model should be useful for correlative and predictive purposes. In conclusion, the complementary chemical and biological analyses used in this study provided a comprehensive assessment which showed that the EDCs discharged from the monitored WWTPs would be expected to have a low impact on the receiving environments.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Environment
Faculty of Environment and Planning
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Hoffmann, Frauke. "Mating behavior as non-invasive biomarker in Xenopus laevis for the assessment of endocrine disrupting compounds." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2012. http://dx.doi.org/10.18452/16519.

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Hormonell wirksame Chemikalien, wie Pflanzenschutzmittel oder Pharmaka gelangen durch Abwässer in die Umwelt und akkumulieren vor allem in Oberflächengewässern. Ein erhöhtes Augenmerk liegt auf Substanzen, die durch (anti)androgene und (anti)östrogene Wirkungsweise die Reproduktion von Tieren und Menschen beeinträchtigen. Bei den bisherigen Nachweismethoden für diese Stoffe handelt es sich um invasive Methoden, die das Töten der Tiere beinhalten. Diesen Methoden mangelt es jedoch an der nötigen Sensitivität, um umweltrelevante Konzentrationen der endokrinen Disruptoren (EDs) nach Kurzzeitexposition nachweisen zu können, sowie am Vermögen, alle vier Wirkmechanismen (androgen, antiandrogen, östrogen und antiöstrogen) mit einer einzelnen Testmethode feststellen und unterscheiden zu können. In dieser Studie wurde deshalb mit Hilfe männlicher Afrikanischer Krallenfrösche (Xenopus laevis) eine Testmethode entwickelt, bei der die Frösche verschiedenen (anti)androgenen und (anti)östrogenen EDs ausgesetzt wurden und ihr Rufverhalten untersucht wurde. Diese nicht-invasive Methode erwies sich als schnell und höchst sensitiv. Zudem war es erstmals möglich, die vier verschiedenen Wirkmechanismen allein anhand veränderter Ruftypen und Rufparameter zu bestimmen und zu unterscheiden. Darüber hinaus konnte gezeigt werden, dass bei Anwendung dieser Methode die Möglichkeit besteht, die Versuchstiere in weiteren Tests wiederzuverwenden, da die Rufparameter nach einer expositionsfreien Zeit von sechs Wochen wieder Kontrollwerte erreichten. Zusammengefasst kann die hier vorgestellte verhaltensphysiologische und damit nicht-invasive Methode als Biomarker für den Nachweis von (anti)androgenen und (anti)östrogenen EDs verwendet werden. Ferner zeigt die hohe Sensitivität des Tests, sowie die Möglichkeit der vollautomatischen Analyse enormer Datenmengen, dass dieser schnelle Verhaltenstest ein großes Potential hat, ein sensitiver, standardisierter und nicht-invasiver Biomarker zu werden.
Endocrine disrupting compounds (EDCs), such as herbicides, pesticides or pharmaceuticals enter the environment via sewage effluents and especially accumulate in surface waters. Research efforts so far mainly focused on EDCs with (anti)androgenic and (anti)estrogenic modes of action (MOAs), which can interfere with reproductive biology of vertebrates. To date, biomarkers for the assessment of such compounds are invasive techniques, which are not sensitive enough to detect EDCs after short-term exposures and which cannot distinguish between the four MOAs. Hence, in this study a non-invasive method for the assessment of EDCs was developed using male African clawed frogs (Xenopus laevis) as model species. Frogs were exposed to individual (anti)androgenic and (anti)estrogenic EDCs in the surrounding water and their calling behavior was analyzed. This non-invasive method turned out to be a fast and highly sensitive biomarker for the detection of (anti)androgenic and (anti)estrogenic EDCs. Moreover, this method was able to differentiate between the four different MOAs solely by determining affected parameters of the calling behavior. It was also shown that by using this method, it might be possible to reuse already tested experimental animals, because the measured affected parameters were reversed after a period of six weeks under control conditions. Taken together the here established non-invasive behavioral method can be used as biomarker for the detection of (anti)androgenic and (anti)estrogenic EDCs. Furthermore, the high sensitivity of this testing method, as well as the possibility of analyzing vast datasets rapidly in a completely automated fashion indicate the huge potential for this rapid behavior test to become a sensitive, standardized, non-invasive biomarker.

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Guimarães, Tatiane Sant\'Ana. "Detecção e quantificação dos hormônios sexuais 17 \'beta\'-estradiol (E2), estriol (E3), estrona (E1) e 17 \'alfa\'-etinilestradiol (EE2) em água de abastecimento: estudo de caso da cidade de São Carlos, com vistas ao saneamento ambiental." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/18/18138/tde-26022009-100015/.

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Um dos grandes problemas da engenharia ambiental é a contaminação dos corpos hídricos. Os sanitaristas têm se preocupado com os hormônios sexuais, notadamente os estrógenos, compostos extremamente ativos biologicamente, que têm sido referidos como agentes etiológicos de feminilização e de vários tipos de cânceres. Os estrógenos naturais 17 \'beta\'-estradiol (E2), estriol (E3), estrona (E1) e o sintético 17 \'alfa\'-etinilestradiol (EE2), desenvolvidos para uso médico em terapias de reposição hormonal feminina e métodos contraceptivos, são os que despertam maiores preocupações, pela contínua introdução ao ambiente; hormônios que possuem a melhor conformação reconhecida pelos receptores que resultam respostas máximas, por isso são considerados responsáveis pela maioria dos efeitos disruptores desencadeados pela disposição de efluentes. A mudança de padrões quanto à atividade sexual dos jovens e a preocupação com o planejamento familiar, levaram ao grande consumo de contraceptivos que, através da urina, são levados pela rede coletora aos corpos de água. O indiscriminado uso desses hormônios na bovinocultura, suinocultura, avicultura e aqüicultura são responsáveis por parte considerável desse contaminante nos mananciais. Os hormônios excretados através da urina e fezes e agentes provenientes das indústrias de processamento de alimentos preocupam os sanitaristas porque o lançamento de efluentes in natura ou tratados, são as principais vias de contaminação do ambiente aquático, quer pelo déficit de infra-estrutura em saneamento, quer pela ineficiência tecnológica e/ou operacional na remoção desses compostos nas estações de tratamento de água ou de efluentes. Apesar de possuírem meia-vida relativamente curta, quando comparados a outros compostos orgânicos como praguicidas, os estrógenos naturais são continuamente introduzidos no ambiente, o que lhes confere caráter cumulativo. A proposta desta pesquisa foi verificar a presença de estrógenos na água bruta que chega à Estação de Tratamento de Água, após seu tratamento, em água tratada por osmose reversa e por tecnologia Milli Q (marca registrada). Para verificar e quantificar presença desses hormônios estrógenos em água de abastecimento de São Carlos-SP, foram realizadas exames através de imunoensaio quimiluminescente e radioimunoensaios. Os resultados apontaram que a ETA não possui solução eficiente para a remoção dos analitos de interesse dessa pesquisa, uma vez que na água tratada foram encontrados valores semelhantes aos da água bruta.
One of the major problems of environmental engineering is the water contamination. The sanitary persons have been concerned with the gonadal hormones, notably the estrogen, biologically active compounds extremely, which have been referred to as etiologic agents of feminization and several types of cancers. The natural estrogen 17 \'beta\'-estradiol (E2), estriol (E3), estrone (E1) and synthetic 17 \'alpha\'-ethinylestradiol (EE2), developed for medical use of hormone replacement therapy in women and contraceptive methods, are those that attract larger concerns by the continuous introduction into the environment; hormones that have the best conformation recognized by receptors that result answers maximum, so they are considered responsible for most of the effects disruptors triggered by the wastewater disposal. The change in patterns on the sexual activity of young people and the concern with family planning, led to the large consumption of contraceptives that, in the urine, are led by the distribution net to water. The indiscriminate use of these hormones in cattle, pigs, poultry and aquaculture are responsible for part of this contaminant in the source. The hormones excreted in the urine and feces and agents from the food processing industries in the sanitary concern that the launch of effluents in nature or treated, are the main routes of contamination of the aquatic environment, either by lack of infrastructure, sanitation, or by inefficiency technological and/or operating in the removal of these compounds in the treatment plants, water or effluent. Despite having relatively short stocking-lige when compared to other organics such as pesticides, natural estrogens are continuously released into the environment, which gives them character cumulative. The proposal of this research was to verify the presence of estrogen in the gross water that arrives at the water treatment plant, after the treatment, in water treated by reverse osmosis and by Milli Q technology. To verify and quantify presence of these hormones estrogen in water supply of San Carlos-SP, examinations were conducted through immunoassay chemiluminescent and radioimunoassays. The results showed that the ETA has no efficient solution for removal of interest analytes of this research, because in the treated water were found values similar to crude water.

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Gerolin, Eleonilce Rosa Rossi. "Ocorrencia e remoção de disruptores endocrinos em aguas utilizadas para abastecimento publico de Campinas e Sumare - SP." [s.n.], 2008. http://repositorio.unicamp.br/jspui/handle/REPOSIP/257939.

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Orientador: Ricardo de Lima Isaac
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo
Made available in DSpace on 2018-08-12T13:40:20Z (GMT). No. of bitstreams: 1 Gerolin_EleonilceRosaRossi_D.pdf: 4382249 bytes, checksum: 11ae4682864ae425b2aad5ee5844f76c (MD5) Previous issue date: 2008
Resumo: A ocorrência de compostos considerados disruptores endócrinos (DE) em efluente de Estação de Tratamento de Esgoto (ETE) e em águas superficiais em concentrações de risco para animais silvestres constitui campo de pesquisa de elevado interesse devido à probabilidade de que esses micropoluentes não sejam removidos nos processos físico-químicos empregados em Estação de Tratamento de Água (ETA) convencional. O presente trabalho avaliou a ocorrência de estrógenos naturais estrona (E1), 17ß Estradiol (E2), Estriol (E3), o estrógeno sintético 17a Etinilestradiol (EE2) e Nonilfenol (NP) em água de abastecimento público das cidades de Campinas e Sumaré-SP. Para tal, coletou-se água bruta (do rio Atibaia, na entrada da estação) e água tratada nas ETAs 3 e 4 de Campinas e ETA 2 de Sumaré, num período de três semanas. Os procedimentos analíticos empregados foram extração em fase sólida e análise por cromatografia líquida de alta eficiência e espectrometria de massa (CLAE-EM/EM). A média dos resultados obtidos para água tratada de Campinas e Sumaré foram, respectivamente, de 0,10 e 0,08 ng/L de E1, 0,92 e 1,30 ng/L de E2, 0,70 e 0,62 ng/L de E3, 275 e 472 ng/L de EE2 e 6,14 e 4 ng/L de NP. O tratamento utilizado em Campinas remove, em média, acima de 80% dos DE em estudo, com exceção de EE2, cuja remoção foi de 38%. Em Sumaré, a remoção foi da ordem de 80% de E1 e E2, 64% de E3 ; 55% NP e 41% de EE2. Considera-se que a oxidação por cloro tenha sido preponderante na remoção dos DE alertando-se, porém, para a probabilidade da formação de subprodutos potencialmente estrogênicos. Mesmo ante tal eficiência de remoção, a presença de DE, detectados em água tratada, ainda que em pequenas concentrações, pode atribuir atividade estrogênica, haja vista que estrógenos naturais e sintéticos no ambiente podem exercer efeitos mesmo em concentrações muito baixas (1ng/L).
Abstract: The occurrence of potential endocrine disruptor compounds (EDC) in wastewater treatment plant (WWTP) effluent and surface waters at high concentrations harmful for aquatic life has been an interesting research field due to the probability of these micro pollutants to break through water treatment plant (WTP). The present paper evaluated the occurrence of natural estrogens such as estrone (E1), 17ß-estradiol (E2), estriol (E3), as well as the synthetic estrogen 17a ethinylestradiol (EE2) and nonylphenol (NP) at water supply systems of Campinas and Sumaré. Raw water from Atibaia River and treated water samples were collected from Campinas WTP-3-and-4 and Sumaré WTP-2 over a three-week period. The analytic technique used was solid phase extraction and liquid chromatography/ tandem mass spectrometry (LC-MS/MS). The average results obtained for drinking water in Campinas and Sumaré were, respectively, 0.03 and 0.06ng/L for E1, 0.93 and 1.32ng/L for E2, 0.70 and 0.72ng/L for E3, 91.2 and 154ng/L for EE2 and 6.14 and 4ng/L for NP. Campinas WTP obtained an average removal of = 80% of focused EDC, except for EE2, whose efficiency was 38%; Sumaré WTP removal efficiency was 80% for E1 and E2, 60% for E3 and NP and 41% for EE2. Chlorine oxidation was probably the major treatment step for EDC removal, though potentially estrogenic by-products could have been formed as well. The presence of EDC in drinking water, despite the low concentrations, could provide estrogenic activity, since it is well known that natural and synthetic estrogen in the environment can produce effects at very low concentration (1ng/L).
Doutorado
Saneamento e Ambiente
Doutor em Engenharia Civil

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Slater, Heather. "Development of a chemical analysis protocol and application with whole estrogenic and androgenic assays to assess endocrine disruptor activity during wastewater and sludge treatment processes." Thesis, University of British Columbia, 2014. http://hdl.handle.net/2429/48628.

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Wastewater and sludge treatment can decrease or increase estrogenic activity through degradation and transformation processes. Endocrine disrupting chemicals (EDCs) tend to adsorb to solids and partition into sludge during the wastewater treatment process. Analytical procedures to detect EDCs in sludge media can be time / labour intensive and require expensive analytical instrumentation. As a result, little information is available on EDC content or fate in municipal sludge. A gas chromatography-mass spectrometry (GC-MS) chemical analysis procedure to detect estrogens in mixed and digested sludges without freeze-drying prior to extraction could not be located in the literature. Therefore, GC-MS chemical analysis protocols were developed for detection of estrone (E1) and 17β-estradiol (E2) in municipal sludges that was also compatible with bioluminescent yeast assays. This protocol is elucidated and summarised for consideration and use by other researchers and the user community. Municipal trickling filter / solids contact wastewater treatment processes were examined for reduction of E1 and E2; whole estrogenic and androgenic activity; and toxic luminescence inhibition. Conventional heat and combinations of microwave irradiation and oxidation treatments were applied to municipal sludge and evaluated using the same methods. The specified wastewater treatment plant reduced total E1 and E2 by 54%; estrogenic activity by 27%; and androgenic activity by 38%. The most potent estrogen, E2, was reduced by 69% and E1 was reduced by 26%. More importantly, the increased ratio of E1 to E2 from 0.6 (influent) to 1.4 (pre-chlorinated effluent), indicated E2 was biologically degraded to the less estrogenic E1. Mesophilic (35–40 °C) sludge digestion reduced E1 by 12%, E2 by 63%, whole estrogenic activity by 73% and androgenic activity by 81%. The digestion process reduced toxicity to the yeast strain, BLYR, by threefold. Overall, microwave irradiation was more effective than conventional heating in reducing concentrations of E1 and E2 in mixed and digested sludges. Oxidative (H₂O₂) treatments did not reduce E1, E2, estrogenic or androgenic activity. The treatment plant reduced E1, E2, estrogenic activity and androgenic activity in the wastewater stream. The anaerobic mesophilic sludge digestion process reduced E1, E2, BLYR toxicity, and whole estrogenic and androgenic activity.
Applied Science, Faculty of
Civil Engineering, Department of
Graduate

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Verbinnen, Raphael Teixeira. "Avaliação da atividade estrogênica das águas do rio Itapecuru no município de Bacabeira-MA." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/75/75135/tde-26012015-112322/.

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O rio Itapecuru foi investigado quanto a sua atividade estrogênica por meio das técnicas de ecotoxicologia aquática e de cromatografia líquida. No município de Bacabeira, amostras de água do rio Itapecuru foram coletadas no ponto de captação do sistema de abastecimento público de água que atende cerca da metade da população de São Luís, capital do Maranhão. Elas foram utilizadas na realização de ensaios ecotoxicológicos crônicos de 21 dias com Danio rerio e Oreochromis niloticus. A VTG nestes organismos-teste foi quantificada por meio do ensaio imunoenzimático ELISA, cujos resultados indicaram a indução de VTG em machos de ambas as espécies. Portanto, a água do rio Itapecuru continha substâncias em concentração suficiente para causar alterações endócrinas no sistema sexual reprodutivo de Danio rerio e de Oreochromis niloticus. Para investigação da ocorrência de 17 β-estradiol (E2) e 17 α-etinilestradiol (EE2), foi desenvolvido um método analítico que utilizou a extração em fase sólida seguida da análise cromatográfica líquida de alta eficiência acoplada a um detector de fluorescência. O método foi validado e demonstrou-se ser seletivo, preciso (E2 = 3,08% e EE2 = 2,26%), exato (E2 = 78,05% e EE2 = 92,26%) e com recuperação adequada (E2 = 99,24% e EE2 = 99,71%). Apresentou também LD de 6,96 e 20,78 ng.L-1 e LQ de 10,36 e 29,33 ng.L-1, respectivamente para E2 e EE2. A robustez, avaliada por meio do teste de Youden, mostrou os pontos robustos e os críticos do método de análise. Nas amostras de água do rio Itapecuru coletadas posteriormente aos testes ecotoxicológicos, encontrou-se EE2, sendo 13,48 ng.L-1 em uma e abaixo do LQ na outra. O estrógeno E2 não foi encontrado em quaisquer das amostras.
The Itapecuru river (Maranhão, Brazil) was investigated regarding its estrogenic activity by means of aquatic ecotoxicology and liquid chromatography. At Bacabeira, water samples were collected at the river Itapecuru uptake point of the public water supply system that serves about half the population of Sao Luis, Brazil. Using them, we performed 21 days chronic ecotoxicological tests using Danio rerio and Oreochromis niloticus. In these test organisms, VTG was quantified by means of enzyme-linked immunosorbent assay ELISA, whose results indicated the induction of VTG in males of both species. Therefore, the Itapecuru river water had substances in concentration sufficient to cause endocrine disruption in the reproductive system of Danio rerio and Oreochromis niloticus. To investigate the occurrence of 17β-estradiol (E2) and 17α-ethinylestradiol (EE2) in that same river, we developed an analytical method using solid phase extraction followed by high performance liquid chromatography coupled to a fluorescence detector. The method was validated and shown to be selective, precise (E2 = 3.08% and EE2 = 2.26%), exact (E2 = 78.05% and EE2 = 92.26%) and with suitable recovery (E2 = 99.24% and EE2 = 99.71%). LOD of 6.96 and 20.78 ng.L-1 and LOQ of 10.36 and 29.33 ng.L-1 were found, respectively to E2 and EE2. The robustness was assessed by Youden test and highlighted the robust and the critical points of the chromatographic method. In two of the water samples analyzed from Itapecuru River, EE2 was found, one of it with 13.48 ng.L-1 and the another below the LOQ. E2 was not detected in any of the samples.

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Dell\'Acqua, Marcelo Marques. "Efeito do hormônio 17α-etinilestradiol sobre a biologia de Chironomus sancticaroli (Chironomidae, Diptera)." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/18/18138/tde-09062017-152252/.

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A água constitui um dos compostos de maior distribuição e importância na crosta terrestre. Sua importância para vida está no fato de que nenhum processo metabólico ocorre sem a sua ação direta ou indireta. Entre os vários compostos contaminantes dos ambientes aquáticos, os hormônios, estrógenos naturais e sintéticos, devem ser vistos com uma maior importância, devido a sua persistência no ambiente. O 17α-etinilestradiol (EE2) é um hormônio sintético utilizado na formulação de contraceptivos orais, transdérmico e injetáveis. O presente estudo tem como objetivo analisar o efeito do hormônio sintético 17α-etinilestradiol sobre a biologia do invertebrado aquático Chironomus sancticaroli analisando três gerações do ciclo de vida da espécie. Nos experimentos foram utilizados areia fina comum (lavada em água corrente, seca em estufa a 60ºC e levada a mufla por 4 horas a 560ºC) e água deionizada (condutividade entre 25-55 μS.cm-1, dureza entre 12 e 16 mg.L-1 para CaCO3, pH entre 6,5 a 7,5). Foram realizadas 4 réplicas utilizando-se potes de 2 litros para cada concentração do hormônio e para o controle. Para os testes, foram colocadas 15 larvas, contendo 60 g de areia de cultivo e 240 ml de solução contendo 17α-etinilestradiol (na proporção 1:4, sedimento-solução) nas concentrações de 50; 100; 200; 400; 800 e 1600 μg.L-1, e fotoperíodo de 12h luz/ 12 h escuro e com temperatura de 22 a 26ºC. Os testes agudos foram realizados utilizando-se larvas de IV ínstar sem aeração e os testes crônicos foram realizados utilizando-se larvas de I ínstar com aeração. Os organismos foram alimentados com 5 ml de uma solução contendo 1 litro de água deionizada e 5,0 g de ração para peixe triturada (TetraMin®). O teste realizado foi estático, ou seja, a solução não era trocada do início ao fim do teste de cada geração F1, F2 e F3. Em testes agudos (96h) os resultados mostraram que o composto em estudo não apresenta toxicidade. Nos testes crônicos apenas a terceira geração mostrou uma baixa sobrevivência (43,3 a 56,6%) indicando toxicidade do composto ao organismo-teste, o que foi confirmado pelo teste ANOVA one-way com p ≤ 0,05. O tempo de emergência do organismo na terceira geração foi de 22 dias, havendo um atraso de cinco dias em comparação aos demais tratamentos, indicando que o composto testado pode influenciar no tempo de desenvolvimento do organismo-teste. Na análise da fecundidade potencial, os testes estatísticos indicaram haver uma diferença significativa entre os tratamentos e o controle somente na terceira geração, o que se pode inferir que o composto testado interfere na fecundidade potencial do Chironomus sancticaroli. Não foram encontradas deformidades bucais nas larvas nas três gerações analisadas. Para tanto, faz-se necessários estudos posteriores, visando um número maior de organismos (n ≥ 100) em um número maior de gerações, para que os resultados sejam mais conclusivos no que diz respeito a interferência do composto testado sobre a biologia do Chironomus sancticaroli.
Water is one of the compounds of great distribution and importance in the Earth\'s. Its importance to life lies in the fact that no metabolic process occurs without its direct or indirect action. Among the various contaminating compounds in aquatic environments, hormones, natural and synthetic estrogens, should be viewed with great importance because of their persistence in the environment. 17α-ethinylestradiol (EE2) is a synthetic hormone used in the formulation of oral, transdermal, and injectable contraceptives. The present study aims to analyze the effect of the synthetic hormone 17α-ethinylestradiol on the biology of the aquatic invertebrate Chironomus sancticaroli analyzing three generations of life cycle. In the experiments, common fine sand was used (washed with deionized water, oven dried at 60ºC and muffled for 4 hours at 560ºC) and deionized water (conductivity between 25-55 μS.cm-1, hardness between 12 and 16 mg.L-1 for CaCO3, and pH between 6.5 to 7.5). Four replicates were performed using 2-liter pots for each concentration of the hormone and for the control. For the tests, 15 larvae, containing 60 g of sand and 240 ml of solution containing 17α- ethinylestradiol (1:4, sediment solution) in the concentrations of 50; 100; 200; 400; 800 and 1600 μg.L-1, and photoperiod of 12h light/12h dark and with a temperature of 22 to 26ºC. The acute tests were performed using III larvae instar without aeration and the chronic tests were performed using I instar larvae with aeration. The organisms were fed with 5 ml of a solution containing 1 liter of deionized water and 5.0 g of crushed fish feed (TetraMin®). The test performed was static, were the solution was not changed from the beginning to the end of the test of each F1, F2 and F3 generation. In acute tests (96h) the results showed that the compound under study shows no toxicity. In chronic tests only the third generation showed a low survival (43.3 to 56.6%) indicating toxicity to the test organism, which was confirmed by the one-way ANOVA test with p ≤ 0.05. The adult emergency of the organism in the third generation was of 22 days, with a delay of five days in comparison to the other treatments, indicating that the compound tested influences development. In the analysis of potential fecundity, the statistical tests indicated that there was a significant difference between the treatments and the control only in the third generation, which can be inferred that the tested compound interferes in the potential fecundity of Chironomus sancticaroli. No oral deformities were found in the larvae in the three generations analyzed. In order to do so, further studies are required, aiming at a larger number of organisms (n ≥ 100) in a larger number of generations, so that the results are more conclusive with respect to the interference of the tested compound on the biology of Chironomus sancticaroli.

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26

Ajj, Hussein. "Influence des micropolluants en mélange sur la croissance de tumeurs testiculaires d'origine germinale." Thesis, Université de Lorraine, 2014. http://www.theses.fr/2014LORR0215/document.

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L’incidence des cancers testiculaires a fortement augmenté au cours des 50 dernières années. Des études épidémiologiques in vitro et in vivo, ont montré que l’exposition des hommes aux perturbateurs endocriniens est impliquée dans l’initiation et la progression du cancer du testicule (Beiki et al., 2010). L’exposition fœtale à ces produits pourrait provoquer des altérations de la différenciation des cellules germinales (CGs) au cours leur développement pendant la vie fœtale. Au cours de cette thèse, nous nous sommes intéressés à déterminer le rôle des perturbateurs endocriniens œstrogéno-mimétiques en mélange sur la prolifération des cellules séminomateuses TCam-2. Nous avons identifié les voies de signalisation impliquées dans la réponse à ces produits. Nous nous sommes focalisés sur les effets d’un mélange d’alkylphénols appelé M4 (4-tert-octylphénol et le 4-nonylphénol), in vitro sur la prolifération des cellules séminomateuses TCam-2, et in vivo sur la croissance de tumeurs obtenues à partir des cellules de carcinome embryonnaire NT2/D1 xénogreffées chez la souris Nude. Dans notre étude, nous avons mis en évidence l’implication d’ERα36, une isoforme tronquée du récepteur ERα, dans la réponse au mélange d’alkylphénols, M4. Ce mélange stimule la prolifération des cellules du cancer testiculaire et l’expression du récepteur ERα36. Ces effets sont médiés par la phosphorylation de CREB via la voie PI3K-ERα36-dépendante, et aboutissent à la diminution de l’expression des gènes de la famille Dnmt3, limitant le niveau de méthylation de l’ADN. ERα36 pourrait donc constituer une cible thérapeutique dans le traitement des cancers testiculaires
In vitro and in vivo epidemiological studies showed that the exposure of men to endocrine disruptors triggers the initiation and the progression of the testis cancer (Beiki et al., 2010). The fetal exposure to these products is able to alter the differentiation of germ cells in the timing of their development during the fetal life. The aim of our study was to determine the role of an endocrine disruptor mix on the proliferation of seminoma cells TCam-2. We also identified the pathways involved. In this study, we focused on the estrogen-like effects of an alkylphenol mixture called M4 (4-tert-octylphenol and 4-nonylphenol): in vitro we measured the proliferation of TCam-2 seminoma cells after M4 exposure and in vivo, we measured the tumor growth of NT2/D1 cells xenografted into Nude mice. The results highlighted the implication of ERα36 receptor, a truncated isoform of ERα, in the response to the alkylphenol mixture M4. This mixture stimulates the cell proliferation of testicular cancer cells and the expression of the ERα36 receptor. These effects are mediated by CREB phosphorylation via the PI3K-ERα36-dependant pathway, and end by downregulation of Dnmt3 genes, thus limiting the level of DNA methylation. Therefore ERα36 appears to be a promising therapeutic target for testis cancer treatment

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27

Essandoh, Helen M. K. "Efficiency of soil aquifer treatment in the removal of wastewater contaminants and endocrine disruptors. A study on the removal of triclocarban and estrogens and the effect of chemical oxygen demand and hydraulic loading rates on the reduction of organics and nutrients in the unsaturated and saturated zones of the aquifer." Thesis, University of Bradford, 2011. http://hdl.handle.net/10454/5710.

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This study was carried out to evaluate the performance of Soil Aquifer Treatment (SAT) under different loading regimes, using wastewater of much higher strength than usually encountered in SAT systems, and also to investigate the removal of the endocrine disruptors triclocarban (TCC), estrone (E1), 17¿-estradiol (E2) and 17¿- ethinylestradiol (EE2). SAT was simulated in the laboratory using a series of soil columns under saturated and unsaturated conditions. Investigation of the removal of Chemical Oxygen Demand (COD), Biochemical Oxygen Demand (BOD), Dissolved Organic Carbon (DOC), nitrogen and phosphate in a 2 meter long saturated soil column under a combination of constant hydraulic loading rates (HLRs) and variable COD concentrations as well as variable HLR under constant COD showed that at fixed HLR, a decrease in the influent concentrations of DOC, BOD, total nitrogen and phosphate improved their removal efficiencies. It was found that COD mass loading applied as low COD wastewater infiltrated over short residence times would provide better effluent quality than the same mass applied as a COD with higher concentration at long residence times. On the other hand relatively high concentrations coupled with long residence time gave better removal efficiency for organic nitrogen. Phosphate removal though poor under all experimental conditions, was better at low HLRs. In 1 meter saturated and unsaturated soil columns, E2 was the most easily removed estrogen, while EE2 was the least removed. Reducing the thickness of the unsaturated zone had a negative impact on removal efficiencies of the estrogens whereas increased DOC improved the removal in the saturated columns. Better removal efficiencies were also obtained at lower HLRs and in the presence of silt and clay. Sorption and biodegradation were found to be responsible for TCC removal in a 300 mm long saturated soil column, the latter mechanism however being unsustainable. TCC removal efficiency was dependent on the applied concentration and decreased over time and increased with column depth. Within the duration of the experimental run, TCC negatively impacted on treatment performance, possibly due to its antibacterial property, as evidenced by a reduction in COD removals in the column. COD in the 2 meter column under saturated conditions was modelled successfully with the advection dispersion equation with coupled Monod kinetics. Empirical models were also developed for the removal of TCC and EE2 under saturated and unsaturated conditions respectively. The empirical models predicted the TCC and EE2 removal profiles well. There is however the need for validation of the models developed
Netherlands Organisation for International Cooperation in Higher Education (Nuffic)
The Appendix files for this thesis are unavailable online via Bradford Scholars.

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28

Julien, Benoit. "Caractérisation des effets métaboliques d’un mélange de polluants à faibles doses dans un modèle de souris déficientes en oestrogènes." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSE1092.

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La ménopause est un facteur de risques associé au développement des maladies métaboliques. Du fait de ce déficit hormonal, les femmes ménopausées pourraient présenter des risques particuliers une fois exposées à des agents chimiques capables de perturber le système endocrinien. Pour en savoir plus, nous avons mis au point un modèle de souris ovariectomisées supplémentées ou non en œstradiol (E2), et exposées de manière chronique à un mélange de polluants (TCDD, PCB153, DEHP et BPA) ajoutés à une alimentation obésogène. Chaque polluant est utilisé à une dose équivalente à la Dose Journalière Tolérable, et l’exposition recouvre différents stades de développement, incluant ou non la période maternelle (gestation + lactation). Nos résultats indiquent qu’en condition d’obésité induite par le régime, l’ovariectomie accentue la prise de poids, l’intolérance au glucose et l’insulino-résistance chez les souris femelles adultes. Ce phénotype est associé à une diminution de la signalisation œstrogénique dans le foie et une dérégulation de l’adipogenèse et de l’inflammation dans le tissu adipeux. De manière intéressante, le mélange de polluants réduit l’impact délétère de l’ovariectomie sur le phénotype métabolique, possiblement par une amélioration de la signalisation œstrogénique dans le foie et le tissu adipeux. Nos résultats suggèrent fortement que ces effets dépendent d’une exposition maternelle. En conclusion, nous montrons que notre mélange de polluants possède une activité œstrogéno-mimétique. Ceci pourrait avoir une implication dans la compréhension du rôle des polluants environnementaux dans le développement des maladies métaboliques chez la femme en transition ménopausique
Menopause is a risk factor associated with the development of metabolic diseases. Because of estrogen deficiency, postmenopausal women may be at particular risk when exposed to chemical agents that can disrupt the endocrine system. To get more insight, we have developed a model of ovariectomized mice supplemented or not with estradiol (E2), and chronically exposed to a mixture of pollutants (TCDD, PCB153, DEHP and BPA) added to an obesogenic diet. Each pollutant was used at a dose close to the Tolerable Daily Intake dose, and the exposure had covered different stages of development, including or not the maternal period (gestation + lactation). Our results indicate that in diet-induced obesity, ovariectomy triggered weight gain, increase glucose intolerance and insulin resistance. This phenotype was associated with decreased estrogenic signaling in liver and deregulation of adipogenesis and inflammation in adipose tissues. Interestingly, the mixture of pollutants reduced the deleterious impact of ovariectomy on the metabolic phenotype, possibly through an alleviation of estrogenic signaling in both liver and adipose tissues. These data were not reproduced in mice not exposed to pollutants during the maternal life. In conclusion, the mixture of pollutants displayed some estrogeno-mimetic activity. This could have implications in understanding the role of environmental pollutants in the development of metabolic diseases in women in menopausal transition

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29

Essandoh, Helen Michelle Korkor. "Efficiency of soil aquifer treatment in the removal of wastewater contaminants and endocrine disruptors : a study on the removal of triclocarban and estrogens and the effect of chemical oxygen demand and hydraulic loading rates on the reduction of organics and nutrients in the unsaturated and saturated zones of the aquifer." Thesis, University of Bradford, 2011. http://hdl.handle.net/10454/5710.

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Abstract:

This study was carried out to evaluate the performance of Soil Aquifer Treatment (SAT) under different loading regimes, using wastewater of much higher strength than usually encountered in SAT systems, and also to investigate the removal of the endocrine disruptors triclocarban (TCC), estrone (E1), 17β-estradiol (E2) and 17α-ethinylestradiol (EE2). SAT was simulated in the laboratory using a series of soil columns under saturated and unsaturated conditions. Investigation of the removal of Chemical Oxygen Demand (COD), Biochemical Oxygen Demand (BOD), Dissolved Organic Carbon (DOC), nitrogen and phosphate in a 2 meter long saturated soil column under a combination of constant hydraulic loading rates (HLRs) and variable COD concentrations as well as variable HLR under constant COD showed that at fixed HLR, a decrease in the influent concentrations of DOC, BOD, total nitrogen and phosphate improved their removal efficiencies. It was found that COD mass loading applied as low COD wastewater infiltrated over short residence times would provide better effluent quality than the same mass applied as a COD with higher concentration at long residence times. On the other hand relatively high concentrations coupled with long residence time gave better removal efficiency for organic nitrogen. Phosphate removal though poor under all experimental conditions, was better at low HLRs. In 1 meter saturated and unsaturated soil columns, E2 was the most easily removed estrogen, while EE2 was the least removed. Reducing the thickness of the unsaturated zone had a negative impact on removal efficiencies of the estrogens whereas increased DOC improved the removal in the saturated columns. Better removal efficiencies were also obtained at lower HLRs and in the presence of silt and clay. Sorption and biodegradation were found to be responsible for TCC removal in a 300 mm long saturated soil column, the latter mechanism however being unsustainable. TCC removal efficiency was dependent on the applied concentration and decreased over time and increased with column depth. Within the duration of the experimental run, TCC negatively impacted on treatment performance, possibly due to its antibacterial property, as evidenced by a reduction in COD removals in the column. COD in the 2 meter column under saturated conditions was modelled successfully with the advection dispersion equation with coupled Monod kinetics. Empirical models were also developed for the removal of TCC and EE2 under saturated and unsaturated conditions respectively. The empirical models predicted the TCC and EE2 removal profiles well. There is however the need for validation of the models developed

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30

Silva, Mariana Aguilera Alencar da. "Avaliação da neurotoxicidade do Bisfenol A em cultura primária de hipocampo." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/9/9141/tde-04102016-152552/.

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O Bisfenol A (BPA) é usado na fabricação de plásticos de policarbonato e resinas epóxi. A exposição pré-natal a esse agente pode causar diversos efeitos, tais como: antecipação da puberdade, hiperplasia de próstata, diminuição do número de espermatozoides, diminuição dos níveis de testosterona, alteração do desenvolvimento e organização tecidual da glândula mamária, diminuição da resposta celular induzida por hormônios, câncer de mama, diabetes, doenças cardiovasculares, alterações das funções de enzimas hepáticas, além de efeitos sobre o desenvolvimento cognitivo. Poucos estudos avaliam os efeitos do BPA sobre as células neuronais, porém existem evidências de que este agente induza a apoptose. O presente trabalho tem como objetivo estudar a neurotoxicidade do BPA, avaliando vias de sinalização que levam a indução da apoptose em cultura primária de hipocampo. As células foram expostas ao BPA nas concentrações de 50, 100, 150, 200, e 250 µM (0,1% DMSO v/v) pelos períodos de 6, 12, 24, e 48 horas para a realização dos ensaios da atividade mitocondrial (MTT) e citotoxicidade pela liberação da enzima Lactato Desidrogenase (LDH). A partir dos resultados de MTT e LDH, foram adotados novos horários de exposição (3, 6 e 9 horas) utilizando somente as concentrações de 200 e 250 µM. Neste novo desenho experimental, foi realizada a quantificação da concentração de BPA na cultura primária por HPLC-PDA, determinação da concentração de Ca2+ intracelular pela quantificação da fluorescência do Fluo-4 AM, caracterização dos mecanismos envolvidos na morte celular por citometria de fluxo e Western Blotting, e avaliação dos receptores de estrógeno ER-α e ER-β por Western Blotting. Nossos resultados apontam que aproximadamente 20% de BPA na concentração de 250 µM após 6 horas de exposição e 18% para a concentração de 200 µM com 9 horas de exposição foram absorvidos pela cultura celular. O ensaio do MTT mostrou que as células expostas a 200 e 250 µM de BPA, por 12, 24 e 48 horas, apresentaram diminuição significativa da função mitocondrial em relação ao controle. Porém, não houve liberação de LDH para o meio de cultura para nenhuma das concentrações de BPA em nenhum dos períodos de incubação, o que sugere que não houve rompimento da membrana plasmática. Foi observada atividade apoptótica somente com a concentração de 250 µM no período de exposição de 6 horas por citometria de fluxo. Não foram encontradas células em necrose, nem alteração na concentração de cálcio intracelular em nenhuma das condições estudadas. Na avaliação dos marcadores de morte celular, observamos aumento da razão de Bax/Bcl-2 para a concentração de 250 µM em todos os períodos de exposição e aumento das caspases 8, 9 e 3 para a concentração de 250 µM no período de exposição de 6 horas, indicando que o BPA deve ativar tanto a via intrínseca como a extrínseca no processo de apoptose. Verificamos ainda, por Western Blotting, que a cultura primária de hipocampo apresenta os receptores de estrógeno ER-α e ER-β. A exposição ao BPA aumentou os ER-α e ER-β avaliados por Western Blotting para as duas concentrações estudadas no período de 6 horas de exposição e, para o período de exposição de 9 horas, houve um aumento do ER-α para a concentração de 250 µM e do ER-β para a concentração de 200 µM. É possível concluir que o BPA pode levar a morte das células neuronais hipocampais por apoptose por ambas as vias intrínseca e extrínseca, sendo o processo de morte celular mais evidente para a concentração de 250 µM no período de 6 horas de exposição. Sugerimos ainda que o aumento observado em ambos os receptores de estrógeno possa representar uma tentativa de interrupção ou reversão do processo de morte celular.
Bisphenol A (BPA) is used in the manufacture of polycarbonate plastics and epoxy resins. The prenatal exposure to this agent may cause several effects, such as anticipation of puberty, prostate hyperplasia, reduced number of sperm, reduced testosterone levels, alteration in the development and tissue organization of the mammary gland, decreased cellular response induced by hormones, breast cancer, diabetes, cardiovascular disease, changes in the functions of liver enzymes, and effects on cognitive development. Few studies have evaluated the effects of BPA in neuronal cells, however there are evidences that this agent may induce apoptosis. This work aims to study the neurotoxicity of BPA, by analyzing the signaling pathways of apoptosis in hippocampus primary culture. Cells were exposed to BPA at 50, 100, 150, 200, and 250 µM (0.1% DMSO v/v) for 6, 12, 24, and 48 hours for the assay of mitochondrial activity (MTT) and the release of the enzyme lactate dehydrogenase (LDH). From the results of MTT and LDH, new exposure times (3, 6 and 9 hours) and only 200 and 250 µM were used. In this new experimental design we performed the quantification of the BPA concentration in the primary culture by HPLC-PDA, intracellular Ca2+ quantification by Fluo-4 AM assay and the characterization of the mechanisms involved in cell death by flow cytometry and Western Blotting assays. Furthermore, evaluation of the estrogen receptor ER-α and ER-β was done by Western Blotting. Our results demonstrate that about 20% of the BPA concentration of 250 µM after 6 hours of exposure and 18% for the concentration of 200 µM with 9 hours of exposure were absorbed by the cell culture. Cells exposed to 200 and 250 µM of BPA for 12, 24 and 48 hours, showed a significant decrease in mitochondrial function, by the MTT assay, compared to control. However, there was no release of LDH into the culture medium for any of the BPA concentrations in any of incubation times studied, which suggests no rupture of the plasma membrane by BPA. Apoptotic activity was observed after 6 hours of exposure to 250µM BPA by flow cytometry. It was not observed cell necrosis and changes in intracellular calcium concentration in any of the studied conditions. Regarding the cell death markers, exposure to 250 µM BPA in all periods of exposure resulted in an increased Bax/Bcl-2 ratio; moreover, an increase in caspase 8, 9 and 3 was detected after exposure to 250 µM BPA for 6 hours. Taken together, these findings indicate that BPA activates both the intrinsic and the extrinsic pathway during the apoptotic process. We also verified by Western Blotting the presence of the estrogen receptors ER-α and ER-β at the primary culture of hippocampus, and that they can be modulated by BPA. The exposure to 200 and 250 µM BPA for 6 hours caused an increase of ER-α and ER-β, however, 9 hours of exposure to 200 µM and 250 µM BPA increased the expression of ER-α and ER-β, respectively. In conclusion, BPA can lead hippocampal neuronal cells to death by both, intrinsic and extrinsic, apoptotic pathways and this process is more evident at 250 µM BPA after 6 hours of exposure. Furthermore, we suggest that the increase of both estrogen receptors might represent an attempt to interrupt or reverse the cell death process.

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31

Mercado-Feliciano, Minerva. "Estrogenic Activity of the Polybrominated Diphenyl Ether Flame Retardant Mixture DE-71." Thesis, 2008. http://hdl.handle.net/1805/1603.

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Indiana University-Purdue University Indianapolis (IUPUI)
Polybrominated diphenyl ethers (PBDEs) are widely used flame retardants suspected to act as endocrine disruptors. We tested the commercial PBDE mixture DE-71 and its in vivo metabolites for estrogenic activity. MCF-7 breast cancer cells culture, ERE-luciferase gene expression, 3H-β-estradiol displacement from recombinant ERα, and ovariectomized (OVX) mice served as bioassays. Although DE-71 did not bind ERα, it was able to increase MCF-7 cell proliferation and this was prevented by the antiestrogen fulvestrant. DE-71 co-treatment reduced the effect of estradiol in MCF-7 cells. In the OVX mouse (BALB/c) 3-day assay, DE-71 administered alone had no effect on uterine or vaginal tissues but when administered subcutaneously potentiated estradiol’s effect on uterine weight in a dose-dependent manner. DE-71 administered SQ to BALB/c mice for 34 days slightly increased uterine epithelial height (UEH), vaginal epithelial thickness (VET) and mammary ductal lumen area, and attenuated the estradiol-induced increase in UEH; these effects were not seen in C57BL/6 mice. DE-71 increased liver weight in BALB/c, C57BL/6 and estrogen receptor-alpha knockout (ERαKO) mice. Liver cytochrome P450 1A (CYP1A) and CYP2B activities increased 2.5-fold and 7-fold respectively when DE-71 was administered PO, but only CYP2B increased (5-fold) after SQ treatment. Six OH-PBDE metabolites were found in mice after 34-day DE-71 treatment and all were able to bind recombinant ERα. Para-hydroxylated metabolites displayed a 10- to 30-fold higher affinity for ERα compared to ortho-hydroxylated PBDEs. Para-OH-PBDEs induced ERE-luciferase and produced an additive effect when coadministered with β-estradiol. DE-71 was also additive with β-estradiol. At high concentrations (≥ 5x10-5 M), ortho-OH-PBDEs were antiestrogenic in the ERE-luciferase assay. In conclusion, DE-71 behaves as a weak estrogen in both MCF-7 breast cancer cells and ovariectomized adult mice. Mice strain, treatment route and duration determined if DE-71 was estrogenic. BALB/c mice are more susceptible to DE-71 effects in estrogen target tissues than C57BL/6 mice. DE-71 increased liver weight, 5%-51% depending on mouse strain and treatment regime, independently of ERα. The observations that the DE-71 mixture does not displace 3H-β-estradiol from ERα while the hydroxylated metabolites do, suggest that the cellular and tissue effects were due to a metabolic activation of individual congeners.

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32

"Effect of dietary and environmental endocrine disruptors on estrogen metabolic enzyme expression." Thesis, 2009. http://library.cuhk.edu.hk/record=b6074976.

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Because of the structural resemblance to the female hormone, phytoestrogen is another important class of endocrine disruptor. In the present project, we evaluated the effects of phytoestrogens isoliquiritigenin (ILN), hesperetin (HES), genistein, (GEN) and naringenin (NAR) on estrogen metabolism and also their effects on MCF-7 tumor growth in ovariectomized nude mice. We found that these phytoestrogens had differential effect on MCF-7 xenografts. NAR and GEN had totally different responses in the tumor growth. In contrast, ILN and HES only deterred MCF-7 xenograft growth when CYP19 was overexpressed in the graft.
Breast cancer is one of the most prevalent female cancers in Hong Kong and western countries. Prolonged exposure to estrogen has been associated with increased risk of breast cancer. Many enzymes are responsible for estrogen metabolism, for instance, aromatase (CYP19) is responsible for biosynthesis; CYP1 family enzymes hydroxylate estrogen; COMT (catechol-O-methyltransferase) inactivates the hydroxyestrogen; and UDP-glucuronosyltransferase 1A1 (UGT1A1) eliminates the estrogen metabolites. In this project, we employed cell and animal models to address estrogen metabolism-related questions under the influence of endocrine disruptors.
TCDD is a prototype compound of a whole class of halogenated aromatic hydrocarbons termed dioxin-like contaminants, which are also known to be endocrine disruptors. Because of their persistence in the environment dioxins are one of the most concerned classes of carcinogens. Humans can be exposed to this pollutant through contaminated food, air, drinking water, etc. We found that pre-ovariectomy administration of TCDD could significantly reduce aromatase expression in the brain but increase the expression in the adipose tissue. Our results suggested that the timing of exposure to the toxicant could determine the estrogenicity of TCDD.
The present project indicated that endocrine disruptors can alter the metabolism of estrogen; however, the significance of this alteration may be specific to tissues' phenotype and the timing of exposure.
Ye Lan.
Source: Dissertation Abstracts International, Volume: 73-01, Section: B, page: .
Thesis (Ph.D.)--Chinese University of Hong Kong, 2009.
Includes bibliographical references (leaves 169-192).
Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
Abstract also in Chinese.

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33

Medková, Jaroslava. "Optimalizace stanovení endokrinních disruptorů v čistírenských kalech a aplikace metody v reálných vzorcích." Master's thesis, 2012. http://www.nusl.cz/ntk/nusl-307047.

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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 endocrine disruptors on the synthesis of estrogen and corticotrophin-releasing hormone in vitro and in vivo." Thesis, 2011. http://library.cuhk.edu.hk/record=b6075154.

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Huang, Hui.
Thesis (Ph.D.)--Chinese University of Hong Kong, 2011.
Includes bibliographical references (leaves 141-154).
Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
Abstract also in Chinese.

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Cotter, Kellie Anne. "Alternative splicing of estrogen receptor alpha: potential mechanism for endocrine disruption and adaptation in teleost fishes." Thesis, 2014. https://hdl.handle.net/2144/15399.

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Accumulating evidence from epidemiological, wildlife, and laboratory studies indicates that abnormalities of reproduction, development and physiology can be ascribed to environmental contaminants with biological activities. Many such contaminants disrupt essential hormone-regulated processes by virtue of their ability to interact with nuclear hormone receptors (endocrine disrupting chemicals, EDC). Of particular concern are chemicals that mimic or block estrogen signaling (xenoestrogens, XE) through their direct interaction with estrogen receptors (ER). The current model of XE action focuses on disrupted transcriptional activity, as measured by changes in the expression of ER-regulated genes. However, transcription is tightly coupled to splicing, by which a single target gene transcript is processed to multiple structurally and functionally different mRNAs. In theory, any XE that interacts with ER to regulate transcription has the potential to disrupt splicing, thereby affecting not only mRNA quantity but also quality. To address this hypothesis, alternative splicing of the gene encoding ER alpha (esr1), itself an estrogen responsive gene, was investigated. In these studies, killifish (Fundulus heteroclitus), an environmentally relevant species, and zebrafish (Danio rerio), an advantageous laboratory fish model, were used. First, the occurrence of ER alpha splice variants in adult tissues, in developing embryos and in response to estrogens in the two species was documented. Additionally, the effects of long-term, multigenerational XE exposure on ER alpha splicing were examined in two killifish populations, one from an estrogenic (polluted) site and a second population from a reference (unpolluted) site. A subset of ER alpha variants from killifish was expressed in cell culture to document their transcriptional activities. To determine the in vivo relationship between estrogen responsiveness and an ER alpha splice variant of interest, esr1 splicing was experimentally altered in living embryos by microinjecting morpholino oligonucleotides, and changes in induction of a panel of estrogen responsive gene targets were measured as markers of effect. These results provide evidence that dysregulation of mRNA processing is also a mechanism of XE action, and suggest that resultant ER alpha splice variants mediate the short-term effects of estrogen disruption and are also part of the adaptive response to long-term, multigenerational XE exposures in the natural environment.

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Dytczak, Magdalena Anna. "Using ozonation and alternating redox potential to increase nitrogen and estrogen removal while decreasing waste activated sludge production." 2008. http://hdl.handle.net/1993/3062.

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The effectiveness of partial ozonation of return activated sludge for enhancing denitrification and waste sludge minimization were examined. A pair of nitrifying sequencing batch reactors was operated in either aerobic or alternating anoxic/aerobic conditions, with one control and one ozonated reactor in each set. The amount of solids decreased with the ozone dose. Biomass in the anoxic/aerobic reactor was easier to destroy than in the aerobic one, generating approximately twice as much soluble chemical oxygen demand (COD) by cell lysis. Increased COD favoured production of extracellular polymers in ozonated reactors, enhancing flocculation and improving settling. Floc stability was also strengthened in prolonged operation in alternating treatment, resulting in declined solids destruction. Dewaterability was better in alternating reactors than in aerobic ones indicating that incorporation of an anoxic zone for biological nutrient removal leads to improvement in sludge dewatering. The negative impact of ozonation on dewaterability was minimal in terms of the long-term operation. Ozone successively destroyed indicator estrogenic compounds, contributing to total estrogen removal from wastewater. Denitrification rate improved up to 60% due to additional carbon released by ozonation. Nitrification rates deteriorated much more in the aerobic than in the alternating reactor, possibly as a result of competition created by growth of heterotrophs receiving the additional COD. Overall, ozonation provided the expected benefits and had less negative impacts on processes in the alternating treatment, although after prolonged operation, benefits could become less significant. The alternating anoxic/aerobic reactor achieved twice the nitrification rates of its aerobic counterpart. Higher removal rates of estrogens were associated with higher nitrification rates, supporting the contention that the nitrifying biomass was responsible for their removal. The alternating treatment offered the better estrogen biodegradation. Microbial populations in both reactors were examined with fluorescent in situ hybridization. Dominance of rapid nitrifiers like Nitrosomonas and Nitrobacter (79.5%) in the alternating reactor, compared to a dominance of slower nitrifiers like Nitrosospira and Nitrospira (78.2%) in the aerobic reactor were found. The findings are important to design engineers, as reactors are typically designed based on nitrifiers’ growth rate determined in strictly aerobic conditions.
October 2008

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Hill, Corinne E. "Effects of Developmental Exposures of Two Emerging Environmental Toxicants on Estrogen-Sensitive Endpoints." 2015. https://scholarworks.umass.edu/masters_theses_2/200.

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Thousands of synthetic chemicals have been released into the environment, causing widespread exposures of wildlife and humans alike. Some of these chemicals are known to disrupt aspects of hormone action thus inducing abnormalities in endocrine tissues and organs. Bisphenol S (BPS) and tetrabromobisphenol A (TBBPA), two largely unstudied chemicals commonly used in consumer products, are suspected to have endocrine disrupting properties based on their similar chemical structures to known endocrine disrupting chemicals (EDCs). To determine whether developmental exposure to BPS or TBBPA induced abnormalities in the ovary, mice were administered oil, BPS or TBBPA during pregnancy and lactation. The ovaries of female offspring were examined for gross morphological, immunohistological and gene expression differences at postnatal day (PND) 22 and week 16. To determine whether these exposures alter responses to hormones, two females from each litter were administered either oil or ethinyl estradiol (EE2) from PND 19-21. Our study identified significant differences in ovarian follicular formation and gene expression after developmental TBBPA and BPS exposures. Most effects were observed at PND22 (pre-puberty), and were apparent after the EE2 challenge, suggesting that changes induced by BPS and TBBPA are age- and hormone- dependent. Our results are consistent with the hypothesis that TBBPA and BPS are EDCs; that these compounds can disrupt development of the ovary; and that the observed effects of TBBPA and BPS exposure are similar to risk factors for ovarian diseases including cancer. These findings may indicate that widespread exposures to BPS and TBBPA could have implications for public health.

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Klammer, Holger. "Pharmakologische Untersuchungen zu endokrinen Effekten des UV-Filters Ethylhexyl-methoxycinnamat." Doctoral thesis, 2006. http://hdl.handle.net/11858/00-1735-0000-0006-ABC4-2.

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Adamusová, Hana. "Využití vysokoúčinných separačních metod pro analýzy biologicky aktivních látek." Doctoral thesis, 2017. http://www.nusl.cz/ntk/nusl-369437.

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In the first part of this doctoral thesis, a new analytical HPLC-MS/MS method for monitoring of concentration changes of 17β-estradiol (βE2) during in vitro mouse sperm capacitation was developed. Capacitation was performed for three initial concentrations of βE2 (200, 20 and 2 μg/L). For all the concentrations a similar trend for the total unbound βE2 was observed. In general, the βE2 concentration decreased to reach its minimum and then increased again. The position of the minimum differed for the individual tested βE2 concentrations. Experimentally obtained results were subjected to the kinetic analysis. The curves fitted through the experimentally determined points displayed an autocatalytic character. For the agreement between the curves obtained by fitting through the experimental points and the theoretical calculated curves, it is necessary to assume that the first step is adsorption of βE2 onto the surface of the sperm controlled by Langmuir isotherm. The kinetic study was also used to study the effects of fluorides and aluminium fluoride complexes on the capacitation of mouse sperm. The experimental points were in very good agreement with the shape of the theoretical curves and this fact verifies the mechanism of the mouse sperm capacitation kinetics. In the second part of this work, two...

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