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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Remoção de (oo)cistos de protozoários e de estrogenicidade em sistemas combinados de tratamento de esgoto sanitário / Removal microorganisms, (oo)cysts of protozoa and estrogenicity in combined wastewater treatment systems

Marcos Schaaf Teixeira da Silva 08 August 2014 (has links)
Atualmente há um grande interesse em estudos voltados para sistema de tratamento de esgoto sanitário. Isso se deve principalmente pela presença de microrganismos e substâncias que podem interferir na saúde humana e ambiental. Dentre os microrganismos patogênicos responsáveis por transmissão de doenças estão os protozoários Giardia spp. e Cryptosporidium spp. No que se refere às substâncias nocivas à saúde humana e ambiental podem ser citados os desreguladores endócrinos que agem sobre o sistema endócrino de homens e animais causando efeitos adversos. Baseado na importância destes estudos, o presente trabalho teve por objetivo avaliar a eficiência de remoção de protozoários patogênicos - Giardia spp. e Cryptosporidium spp. e da atividade de estrogenicidade em processos de tratamento de esgoto sanitário constituídos por reator UASB, sistema de lodos ativados e filtro de areia. Também foram avaliados os padrões de qualidade dos efluentes do reator UASB e sistema de lodos ativados utilizando sulfato de alumínio e cloreto férrico. A combinação dos processos biológicos sequenciais apresentou robustez em termos de remoção de matéria orgânica, microrganismos indicadores e (oo)cistos. A desinfecção com cloro mostrou-se eficiente em inativar os microrganismos indicadores: coliformes totais e Escherichia coli. A atividade estrogênica, avaliada pelo teste YES, foi maior no efluente do lodo ativado e do filtro de areia devido à conjugação dos compostos estrogênicos no esgoto bruto. Detectou-se toxicidade à levedura utilizada no teste YES (Saccharomyces cerevisae), principalmente nas menores diluições, a qual interferiu na expressão da estrogenicidade impossibilitando o cálculo em termos de concentração equivalente de 17β-estradiol. / Currently there is great interest in studies related to the wastewater treatment system. This is mainly for the present of microorganisms and substances that can interfere with human and environmental health. Among the pathogens responsible for diDEse transmission are protozoa Giardia spp. and Cryptosporidium spp. With regard to substances harmful to human and environmental health can cite endocrine disrupters that act on the endocrine system of humans and animals causing adverse effects. Based on the importance of these studies, the present study aimed to evaluate the efficiency of removal of pathogenic protozoa - Giardia spp. and Cryptosporidium spp. - Activity and estrogenicity in processes of wastewater treatment consisting of UASB reactor, activated sludge system and sand filter. We also evaluated the quality standards of the effluent of the UASB reactor and activated sludge system using aluminum sulfate and ferric chloride. The combination of hardiness sequential biological processes presented in terms of removal of organic matter, microorganisms and indicators (oo) cysts. The chlorine disinfection proved effective in inactivating microorganisms indicators: total coliforms e Escherichia coli. The estrogenic activity, assessed by the YES assay, was higher in the effluent of the activated sludge and sand filter due to a combination of estrogenic compounds in raw sewage. Was detected toxicity to the yeast used in the YES assay (Saccharomyces cerevisiae), mainly in the lower dilutions, which interfered with the expression of estrogenicity it impossible to calculate in terms of an equivalent concentration of 17β-estradiol.
2

SYNTHESES AND ESTROGENICITY STUDY OF DIETHYLSTILBESTROL AND BISPHENOL-A ANALOGS AS POTENTIAL REPLACEMENT FOR BISPHENOL-A AND INVESTIGATION ON NOVEL REACTIONS INDUCED BY IODANE/QUATERNARY AMMONIUM HALIDES

Potturi, Hima 01 August 2011 (has links)
Dynamic isomerization of diethylstilbestrol (DES) makes it difficult to ascertain the active estrogen between its E and Z isomers. An indirect approach has been used in this project to identify the active estrogen. Methoxylated E- and Z-DES (13 and 14) and 9,10-diethylphenanthrene-3,6-diol (15), a closed ring analog of Z-DES, were synthesized and tested for their estrogenicity. The estrogenicity of 13 is higher than that of 14 and 15, which indicates that E-DES is more estrogenic than Z-DES. Dimethylstilbestrol (16), another analog of DES, was also synthesized and tested. Its estrogenicity is lower than that of DES. Non-estrogenic analogs of bisphenol-A were designed based on the observation that (15) is far less estrogenic than DES. Closed ring analogs of bisphenol-A, 3,6-dihydroxy-9,9-dimethylfluorene (34), 2,6-dihydroxy-9,9-dimethylfluorene (35), and 2,7-dhydroxy-9,9-dimethylfluorene (36) were synthesized and they were found to have little or no estrogenicity. An open ring analog of bisphenol-A, 2-(3-hydroxyphenyl)-2-(4-hydroxyphenyl)propane (33) was also synthesized and its estrogenicity is much lower than that of bisphenol-A. Polycarbonate of 36 was also synthesized and its glass transition temperature was measured using differential scanning calorimetry (DSC). Glass transition temperature of polycarbonate of 36 was found to be 199.92 oC, which is about 50o higher than that of bisphenol-A polycarbonate (150 oC). This indicates that polycarbonate of 36 forms a harder plastic than bisphenol-A polycarbonate. Compounds 2,8-dihydroxy-5,5-dioxo-dibenzothiophene (69) and 2,8-dihydroxydibenzothiophene (70) were also synthesized and were tested as non-estrogenic alternatives for bisphenol-S and bisphenol sulfide, respectively. Compound 69 and 70 were found to be less estrogenic than bisphenol-S and bisphenol sulfide respectively agreeing with our hypothesis. Iodane/quaternary ammonium halide in nitromethane was utilized to explore aromatic bromination, N-nitrosation-dealkylation, and benzoate ester formation from benzylamines. Koser's reagent was found to be a suitable iodane for aromatic bromination reaction, whereas for N-nitrosation-dealkylation, IBX gave the best yields. Further, for N-nitrosation-dealkylation reaction, the halides of quaternary ammonium salts play a crucial role. The effectiveness of halides follows F- > Cl- > Br- ~ I-. The lack of N-nitrosation-dealkylation and ester formation in the absence of nitromethane indicates that nitromethane is playing an essential role as well. Yields of benzoate ester from benzyl amines were low (~22%). Optimization experiments will be performed in the future. Plausible reaction mechanisms for these reactions were proposed. Aromatic bromination was thought to be induced either by iodane/halide adduct or by BrOH that was formed from iodane/halide adduct. Ester formation and N-nitrosation-dealkylation were believed to be induced either by alkyl nitrite or by nitrous acid, generated from the reaction of iodane/halide adduct with nitromethane.
3

Human health implications of exposure to xenoestrogens from food

Thomson, Barbara Mary January 2005 (has links)
This thesis aims to assess the human health impact of exposure to estrogenic compounds from the diet. A multi-disciplinary approach is taken to address various aspects of this issue. An introduction to xenoestrogens, including international research priorities, wildlife and human health effects, mechanisms of action, structure activity relationships and additivity of estrogenic effects is provided as background information. An assessment of exposure to a range of naturally occurring and synthetic estrogenic compounds found in food is derived in Chapter 2. The assessment combines new and existing data on food concentration, food consumption and serum levels for each xenoestrogen. Exposure is combined with relative estrogenic potency data from published bioassasy data to estimate risk relative to normal circulating levels of estradiol. Assuming additivity of xenoestrogens, for an average New Zealand male and for post-menopausal women, xenoestrogens in the diet contribute an additional 12-90% of estrogenicity above normal circulating levels. For a pre-menopausal female, the contribution from the diet represents in the order of an additional 2%. The level of exposure determined in this thesis would seem to be of pharmacological relevance, especially for men with low levels of estrogen and for post-menopausal women. Bisphenol A (BPA) is an important monomer used in the manufacture of epoxy resins for internal food can linings. A survey of the BPA content of a range of 80 canned foods available to the New Zealand consumer was undertaken and the results used in the exposure and risk assessments. BPA was detected in all foods analysed except soft drinks, at concentrations ranging from <10-29 µg/kg, except for individual samples of tuna, corned beef and coconut cream that were 109, 98 and 191 µg/kg respectively. None, of over 4000 individual exposure scenarios, exceeded the temporary Tolerable Daily Intake (TDI) of 10 µg/kg body weight per day set by the Scientific Committee on Food in 2002. Intestinal microflora influence the bioavailability of the naturally occurring xenoestrogens genistein and daidzein that contribute significantly to total estrogenicity from the diet. The degradation of genistein and daidzein by the faecal microfloral of 5 human subjects was variable and unpredictable between individuals and within an individual. These findings have important implications for the promotion and prescription of soy foods and supplements for disease prevention and health benefits. The "yeast assay" is one of a number of methods available to measure estrogenicity. This assay was established and validated. In utero exposure to estrogenic compounds at critical periods of sexual differentiation and endocrine development may imprint for health effects observed later in life. Placental transfer of estrogenicity, from 17β-estradiol was studied using the human placental perfusion model and the yeast assay. The placenta provides a protective barrier to the transfer of estrogenicity. Experiments with genistein showed that 5-15% placental transfer occurred, suggesting that in utero exposure might be in the order of 10% of maternal exposure. The thesis concludes with consideration of a genomic approach to substantiate, or refute, the mechanistic link between exposure to xenoestrogens and claimed human health effect. Such an approach offers exciting opportunity to clarify the mode of action of the synthetic versus the naturally occurring xenoestrogens, to confirm or dispute additivity of effect that is an important premise of the exposure assessment, to identify key genes involved in the many possible health effects and thence risk to the individual from dietary exposure to xenoestrogens.
4

Degradation of estrogenic endocrine disruptors by laccases: from estrogenicity monitoring methods to reactor design

Blavier, Julie 28 December 2015 (has links)
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
5

Cloração de água com 17\'beta\'-estradiol e utilização do teste YES para avaliação de estrogenicidade / Chlorination of water with 17\'beta\'-estradiol and application of the YES test for estrogenicity assessment

Natália Fischer 02 July 2013 (has links)
Recentemente, a identificação de substâncias consideradas desreguladores endócrinos em meios aquáticos e a associação destas substâncias com alterações nas comunidades aquáticas, como dificuldades de reprodução em populações de peixes, mostra a importância da pesquisa de tratamentos mais eficientes para a remoção destas substância, bem como uma compreensão maior dos mecanismos de sua oxidação. Dentre estas substâncias de interesse, destacam-se alguns fármacos e hormônios naturais e sintéticos, como é o caso do 17\'beta\'-estradiol. A oxidação com cloro é uma alternativa eficiente para a remoção destas substâncias, mas a formação de subprodutos da oxidação gera preocupações quanto ao risco destes compostos continuarem a apresentar atividade estrogênica, e portanto riscos à comunidade aquática. A proposta desta pesquisa é estudar a oxidação com cloro do 17\'beta\'-estradiol em água de abastecimento, com foco na avaliação da remoção da estrogenicidade utilizando o teste YES. A escolha pela cloração foi feita visto que este é o tratamento mais difundido no Brasil, assim as concentrações e tempos de contato estudados também foram definidos de forma a corresponder àqueles utilizados regularmente em Estações de Tratamento de Água. / In the past years, the identification of some substances classified as endocrine disruptors in water environments has been associated with alterations in these environments dynamics, such as reproduction difficulties in fish populations. Such problems show the need for more efficient removal techniques of these substances and a greater understanding of the mechanisms involved in their oxidation. Among these substances are some pharmaceuticals, natural and synthetic hormones, such as 17\'beta\'-estradiol. Chlorination is an eficcient treatment alternative for removing these substances. However the formation of chlorination by-products is a concerning risk of this treatment, since some by-products may still possess estrogenic activity, therefore continuing to offer risks to the water environment. The aim of this research is to study the 17\'beta\'-estradiol chlorination in drinking water, with emphasis on estrogenicity removal using the YES test. Chlorination was chosen since this is the most used oxidation process in Brazil. Likewise the chlorine concentrations and contact times used in this study were chosen to correspond to those usually used in Water Treatment Plants.
6

Human health implications of exposure to xenoestrogens from food

Thomson, Barbara Mary January 2005 (has links)
This thesis aims to assess the human health impact of exposure to estrogenic compounds from the diet. A multi-disciplinary approach is taken to address various aspects of this issue. An introduction to xenoestrogens, including international research priorities, wildlife and human health effects, mechanisms of action, structure activity relationships and additivity of estrogenic effects is provided as background information. An assessment of exposure to a range of naturally occurring and synthetic estrogenic compounds found in food is derived in Chapter 2. The assessment combines new and existing data on food concentration, food consumption and serum levels for each xenoestrogen. Exposure is combined with relative estrogenic potency data from published bioassasy data to estimate risk relative to normal circulating levels of estradiol. Assuming additivity of xenoestrogens, for an average New Zealand male and for post-menopausal women, xenoestrogens in the diet contribute an additional 12-90% of estrogenicity above normal circulating levels. For a pre-menopausal female, the contribution from the diet represents in the order of an additional 2%. The level of exposure determined in this thesis would seem to be of pharmacological relevance, especially for men with low levels of estrogen and for post-menopausal women. Bisphenol A (BPA) is an important monomer used in the manufacture of epoxy resins for internal food can linings. A survey of the BPA content of a range of 80 canned foods available to the New Zealand consumer was undertaken and the results used in the exposure and risk assessments. BPA was detected in all foods analysed except soft drinks, at concentrations ranging from <10-29 µg/kg, except for individual samples of tuna, corned beef and coconut cream that were 109, 98 and 191 µg/kg respectively. None, of over 4000 individual exposure scenarios, exceeded the temporary Tolerable Daily Intake (TDI) of 10 µg/kg body weight per day set by the Scientific Committee on Food in 2002. Intestinal microflora influence the bioavailability of the naturally occurring xenoestrogens genistein and daidzein that contribute significantly to total estrogenicity from the diet. The degradation of genistein and daidzein by the faecal microfloral of 5 human subjects was variable and unpredictable between individuals and within an individual. These findings have important implications for the promotion and prescription of soy foods and supplements for disease prevention and health benefits. The "yeast assay" is one of a number of methods available to measure estrogenicity. This assay was established and validated. In utero exposure to estrogenic compounds at critical periods of sexual differentiation and endocrine development may imprint for health effects observed later in life. Placental transfer of estrogenicity, from 17β-estradiol was studied using the human placental perfusion model and the yeast assay. The placenta provides a protective barrier to the transfer of estrogenicity. Experiments with genistein showed that 5-15% placental transfer occurred, suggesting that in utero exposure might be in the order of 10% of maternal exposure. The thesis concludes with consideration of a genomic approach to substantiate, or refute, the mechanistic link between exposure to xenoestrogens and claimed human health effect. Such an approach offers exciting opportunity to clarify the mode of action of the synthetic versus the naturally occurring xenoestrogens, to confirm or dispute additivity of effect that is an important premise of the exposure assessment, to identify key genes involved in the many possible health effects and thence risk to the individual from dietary exposure to xenoestrogens.
7

Avaliação da atividade estrogênica em esgotos sanitários e águas de reúso na região metropolitana de São Paulo / Evaluation of estrogenic activity on sanitary wastewater and reclaimed reclaimed water of São Paulo metropolitan region

Vania Rodrigues Lopes 03 December 2015 (has links)
Os esgotos sanitários concentram compostos que são interferentes endócrinos. Os tratamentos de esgotos convencionais por sistema de lodos ativados podem não remover totalmente estes compostos, os quais atingem os ecossistemas aquáticos e oferecem riscos ecológicos e à saúde humana. Neste trabalho, mediu-se a atividade estrogênica de compostos presentes em esgotos brutos, tratados e águas de reúso de duas estações de tratamento de esgotos (ETE) da região metropolitana de São Paulo, que operam por sistema de tratamento por lodos ativados e produzem águas de reúso para fins não potáveis por tratamento físico-químico. Nesse procedimento, as amostras foram preparadas por extração de fase sólida e utilizou-se o bioensaio BLYES (Bioluminescence Yeast Estrogen Screen) para a quantificação de efeito de atividade estrogênica em nanogramas de 17-estradiol equivalente (ng-EEQ/L). A estrogenicidade da amostra foi calculada por meio da EC50 (concentração efetiva em 50%), para isto foram utilizadas diluições seriadas para curva padrão com 17-estradiol e para cada amostra analisada. A toxicidade nos ensaios foi medida e monitorada pela levedura controle BLYR. A atividade estrogênica no esgoto bruto variou de 14,7 a 52,6 ng-EEQ/L Os resultados em esgotos tratados por sistema de lodos ativados variaram de abaixo o limite de quantificação do bioensaio de < 0,10 ng-EEQ/L a 11ng-EEQ/L, indicando eficiência de remoção entre 50% a 100%. As águas de reúso foram produzidas por filtração e cloração e na maioria dos resultados apresentaram atividade estrogênica de <0,10 ng-EEQ/L. Os resultados obtidos neste estudo foram comparáveis aos encontrados na literatura medidos pelo bioensaio YES. Os resultados demonstraram que o bioensaio BLYES foi viável para quantificar a estrogenicidade em todas as amostras testadas. As evidências acerca da atividade estrogênica das águas estudadas podem subsidiar ações integradas na gestão da qualidade das águas, o aprimoramento de condições operacionais e tecnológicas das ETEs / The wastewater concentrates compounds with endocrine disruptors. The conventional wastewater treatment by activated sludge are not able to completely remove these compounds, whose achieve aquatic ecosystems and offer ecologic risks and to human health. In this study we measured estrogenic activity on raw and treated wastewater and reclaimed water from two wastewater treatment plants (WWTPs) in the metropolitan region of São Paulo. These WWTPs treat wastewater by activated sludge process and produce reclaimed water for non potable purposes by physical chemical processes. By this procedure, the samples were collected on both WWTPs before and after described treatments and they were prepared by solid phase extraction (SPE). The samples after SPE were analyzed by the BLYES (Bioluminescence Yeast Estrogen Screen) bioassay for quantifying estrogenic activity measured by nanograms 17-estradiol equivalent per litre (ng-EEQ/L). The estrogenicity of sample was calculated by EC50 (half maximal effective concentration), for that were applied serial dilutions to 17-estradiol standard curve and for each sample. They were implemented serial dilutions for monitoring samples toxicity by BLYR yeast control. The estrogenic activity on raw wastewater ranged by 14,7 to 52,6 ng-EEQ/L. The treated wastewater by activated sludge presented results below the quantification of assay limit of < 0,10 ng-EEQ/L to 11ng-EEQ/L, indicating removal efficiency between 50% to 100%. The reclaimed water was produced by chlorination and filtration and presented results of estrogenic activity of < 0,10 ng-EEQ/L on majority analyzed samples. The results showed that BLYES bioassay was viable to quantify estrogenicity in all tested samples. The evidences on estrogenic activity in studied waters may offer subsidies for integrated actions on water quality management, improvements on operational conditions and technologies of WWTPs
8

Avaliação da atividade estrogênica em esgotos sanitários e águas de reúso na região metropolitana de São Paulo / Evaluation of estrogenic activity on sanitary wastewater and reclaimed reclaimed water of São Paulo metropolitan region

Lopes, Vania Rodrigues 03 December 2015 (has links)
Os esgotos sanitários concentram compostos que são interferentes endócrinos. Os tratamentos de esgotos convencionais por sistema de lodos ativados podem não remover totalmente estes compostos, os quais atingem os ecossistemas aquáticos e oferecem riscos ecológicos e à saúde humana. Neste trabalho, mediu-se a atividade estrogênica de compostos presentes em esgotos brutos, tratados e águas de reúso de duas estações de tratamento de esgotos (ETE) da região metropolitana de São Paulo, que operam por sistema de tratamento por lodos ativados e produzem águas de reúso para fins não potáveis por tratamento físico-químico. Nesse procedimento, as amostras foram preparadas por extração de fase sólida e utilizou-se o bioensaio BLYES (Bioluminescence Yeast Estrogen Screen) para a quantificação de efeito de atividade estrogênica em nanogramas de 17-estradiol equivalente (ng-EEQ/L). A estrogenicidade da amostra foi calculada por meio da EC50 (concentração efetiva em 50%), para isto foram utilizadas diluições seriadas para curva padrão com 17-estradiol e para cada amostra analisada. A toxicidade nos ensaios foi medida e monitorada pela levedura controle BLYR. A atividade estrogênica no esgoto bruto variou de 14,7 a 52,6 ng-EEQ/L Os resultados em esgotos tratados por sistema de lodos ativados variaram de abaixo o limite de quantificação do bioensaio de < 0,10 ng-EEQ/L a 11ng-EEQ/L, indicando eficiência de remoção entre 50% a 100%. As águas de reúso foram produzidas por filtração e cloração e na maioria dos resultados apresentaram atividade estrogênica de <0,10 ng-EEQ/L. Os resultados obtidos neste estudo foram comparáveis aos encontrados na literatura medidos pelo bioensaio YES. Os resultados demonstraram que o bioensaio BLYES foi viável para quantificar a estrogenicidade em todas as amostras testadas. As evidências acerca da atividade estrogênica das águas estudadas podem subsidiar ações integradas na gestão da qualidade das águas, o aprimoramento de condições operacionais e tecnológicas das ETEs / The wastewater concentrates compounds with endocrine disruptors. The conventional wastewater treatment by activated sludge are not able to completely remove these compounds, whose achieve aquatic ecosystems and offer ecologic risks and to human health. In this study we measured estrogenic activity on raw and treated wastewater and reclaimed water from two wastewater treatment plants (WWTPs) in the metropolitan region of São Paulo. These WWTPs treat wastewater by activated sludge process and produce reclaimed water for non potable purposes by physical chemical processes. By this procedure, the samples were collected on both WWTPs before and after described treatments and they were prepared by solid phase extraction (SPE). The samples after SPE were analyzed by the BLYES (Bioluminescence Yeast Estrogen Screen) bioassay for quantifying estrogenic activity measured by nanograms 17-estradiol equivalent per litre (ng-EEQ/L). The estrogenicity of sample was calculated by EC50 (half maximal effective concentration), for that were applied serial dilutions to 17-estradiol standard curve and for each sample. They were implemented serial dilutions for monitoring samples toxicity by BLYR yeast control. The estrogenic activity on raw wastewater ranged by 14,7 to 52,6 ng-EEQ/L. The treated wastewater by activated sludge presented results below the quantification of assay limit of < 0,10 ng-EEQ/L to 11ng-EEQ/L, indicating removal efficiency between 50% to 100%. The reclaimed water was produced by chlorination and filtration and presented results of estrogenic activity of < 0,10 ng-EEQ/L on majority analyzed samples. The results showed that BLYES bioassay was viable to quantify estrogenicity in all tested samples. The evidences on estrogenic activity in studied waters may offer subsidies for integrated actions on water quality management, improvements on operational conditions and technologies of WWTPs

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