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Avaliação in vitro de propriedades mecânicas, químicas e antimicrobianas de um selante de fossas e fissuras isento de bisfenol A; In vitro evaluation of mechanical, chemical and antimicrobial properties of a bisphenol A-free pit-and-fissure sealant

Aguiar, Soraia Monique Fiorati
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 21/05/2010 PT
Relevância na Pesquisa
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Tendo em vista o importante papel desempenhado pelos selantes de fossas e fissuras na prevenção da cárie dental, o objetivo do presente estudo foi avaliar in vitro propriedades mecânicas, químicas e ntimicrobianas do selante isento de bisfenol A Embrace Wetbond™. Para os testes de resistência ao cisalhamento e microinfiltração foram selecionados 135 terceiros molares hígidos, extraídos de humanos, divididos aleatoriamente em 6 grupos: (I) selante Fluroshield® sem contaminação; (II) selante Embrace Wetbond™ sem contaminação; (III) selante Fluroshield® contaminado com saliva; (IV) selante Embrace Wetbond™ contaminado com saliva; (V) selante Fluroshield® contaminado com água; e (VI) selante Embrace Wetbond™ contaminado com água. No estudo de resistência ao cisalhamento os dentes foram seccionados no sentido vestíbulo-lingual, a porção radicular removida e as superfícies mesiais e distais foram embebidas em resina de poliéster. Após o condicionamento do esmalte, foi aplicado o selante com o auxílio de uma matriz de Teflon®. Os espécimes foram termociclados e submetidos ao teste de resistência ao cisalhamento com uma velocidade de 0,5mm/min e célula de carga de 50kgf. Os resultados foram comparados empregando a análise de variância (ANOVA) e pós-teste de Tukey. No estudo de microinfiltração...

Análise dos efeitos tóxicos do nonilfenol e do bisfenol A em organismos de água doce; The effects of nonylphenol and bisphenol A on freshwater organisms

Spadoto, Mariângela
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 15/02/2013 PT
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O bisfenol A (BPA) e o nonilfenol (NP), presentes em detergentes, pesticidas, plásticos e resinas, são conhecidos como Endocrine Disrupting-Chemicals (EDCs), Disruptores ou Desreguladores Endócrinos (DE) ou ainda Perturbadores Endócrinos ou Interferentes Endócrinos. O desregulador endócrino pode ser definido como uma substância química exógena ou mistura, que promove alterações em uma ou mais funções do sistema endócrino e na sua estrutura, causando, conseqüentemente, efeitos adversos na saúde de um organismo, ou a sua descendência. Esses compostos estão presentes nas águas de abastecimento, nos efluentes domésticos e industriais. Os desreguladores endócrinos têm ação mimética aos hormônios tanto no sítio de ligação quanto nos efeitos provocados nos seres vivos a eles expostos. Os compostos bisfenol A e nonilfenol foram identificados como desreguladores endócrinos em inúmeros trabalhos em diversos países, porém sendo pouco os efeitos em organismos tropicais. Este estudo teve como objetivo avaliar a toxicidade aguda do bisfenol A e do nonilfenol para Daphnia similis e Ceriodaphnia silvestrii, bem como, a toxicidade crônica para Ceriodaphnia silvestrii e Chironomus xanthus. Nos testes de toxicidade aguda com BPA os valores de CE(I)50; 48h foram de 10...

DETECTION of BISPHENOL A on A SCREEN-PRINTED CARBON ELECTRODE IN CTAB MICELLAR MEDIUM

Brugnera, Michelle Fernanda; Goncalves Trindade, Magno Aparecido; Zanoni, Maria Valnice Boldrin
Fonte: Taylor & Francis Inc Publicador: Taylor & Francis Inc
Tipo: Artigo de Revista Científica Formato: 2823-2836
ENG
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); This work illustrates the effect of cetyltrimethylammonium bromide (CTAB) as an antifouling and pre-concentrating agent for electroanalytical measurement of bisphenol A (BPA) on a screen-printed carbon electrode. The calibration graphs are obtained for BPA from 1.0 x 10(-6) to 1.0 x 10(-5) mol L(-1) in B-R buffer pH 8.0 with addition of CTAB in a ratio of [CTAB]/[BPA] 2: 1 and the limit of detection was 5.1 x 10(-8) mol L(-1). Nonylphenol can be also monitored by SWV at a potential 170mV more positive than bisphenol A in B-R buffer pH 11.0 in the presence of CTAB. The method was successfully applied for BPA determination in river water and sewage without any pretreatment of the samples.

Indole-3-carbinol attenuates the deleterious gestational effects of bisphenol A exposure on the prostate gland of male F1 rats

Brandt, Joyce Zalotti; Silveira, Livia Teresa R.; Grassi, Tony Fernando; Anselmo-Franci, Janete A.; Favaro, Wagner Jose; Felisbino, Sergio Luis; Barbisan, Luis Fernando; Scarano, Wellerson Rodrigo
Fonte: Elsevier B.V. Publicador: Elsevier B.V.
Tipo: Artigo de Revista Científica Formato: 56-66
ENG
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Processo FAPESP: 10/17262-0; Processo FAPESP: 11/01954-2; Processo FAPESP: 10/14110-4; Bisphenol A (BPA) is a chemical that has been investigated for it potential to cause prostate diseases. In this study, pregnant Sprague-Dawley rats were treated with 25 or 250 mu g/kg BPA from gestational day (GD) 10 to GD21 with or without concurrent indole-3-carbinol (I3C) feeding. I3C is a phytochemical, and it affords chemoprotection against many types of neoplasia. Male F1 rats from different litters were euthanized on post-natal day (PND) 21 and PND180. BPA-treated groups showed a significant increase in histopathological lesions, but I3C feeding reversed many of these changes, mainly at PND180. Maternal I3C feeding increased prostate epithelial apoptosis in the BPA-treated groups and across age groups. Furthermore, I3C induced partial normalization of the prostate histoarchitecture. The results pointed to a protective effect of maternal I3C feeding during pregnancy in the BPA-exposed male offspring, thereby indicating reduction in the harmful effects of gestational BPA imprinting on the prostate. (C) 2013 Elsevier Inc. All rights reserved.

Análise comparativa dos padrões de proliferação e morte celular na próstata ventral de gerbilos sob os efeitos do bisfenol A e cádmio em condições androgênicas normais e após a orquiectomia = : Comparative analysis of proliferation and cell death patterns in the ventral prostate of gerbils under the effects of bisphenol A and cadmium in androgenic normal conditions and after orchiectomy; Comparative analysis of proliferation and cell death patterns in the ventral prostate of gerbils under the effects of bisphenol A and cadmium in androgenic normal conditions and after orchiectomy

Simone Jacovaci Colleta
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 26/03/2015 PT
Relevância na Pesquisa
672.6248%
A próstata é uma glândula acessória do sistema reprodutor que apresenta desenvolvimento e manutenção regulados por andrógenos e estrógenos. Interferências na ação desses hormônios podem predispor esta glândula a desenvolver doenças como hiperplasia prostática benigna e câncer. O bisfenol A (BPA) e cádmio (Cd) são poluentes ambientais que possuem atividade estereogênica. O BPA e Cd entram no corpo humano, principalmente através da ingestão oral. Assim, o objetivo deste estudo foi avaliar se a exposição ao BPA e ao Cd durante a puberdade pode causar alterações na morfologia, proliferação e morte celular na próstata ventral de gerbilos normais e castrados. Para cumprir estes propósitos foram realizadas técnicas morfológicas, serológicas e immunocitoquímicas (PCNA para detecção de células proliferativas e TUNEL/ caspase-3 para a detecção de células apoptóticas). Os resultados demonstraram que 7 dias depois da exposição ao BPA e Cd, individualmente ou em combinação sob condições androgênicos normais, houve um aumento na altura do epitélio e na espessura da camada muscular lisa (SML). O BPA e Cd individualmente induziram o aumento expressão celular de PCNA e caspase-3. Em associação, o BPA e Cd causam aumento das células imunomarcados por TUNEL. Nos animais castrados...

Occurrence of nonylphenol and bisphenol-A in surface waters from Portugal

Azevedo,Débora de A.; Lacorte,Silvia; Viana,Paula; Barceló,Damià
Fonte: Sociedade Brasileira de Química Publicador: Sociedade Brasileira de Química
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2001 EN
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The occurrence of the endocrine disruptor compounds, such as 4-nonylphenol isomers and bisphenol A was determined in surface water samples from Portugal. The analytical method used involved the preconcentration of 200 mL of water sample by solid phase extraction (SPE) using a OASIS (Waters) cartridge, followed by Gas Chromatography-Mass Spectrometry (GC/MS) determination. Recoveries and limits of detection of 4-nonylphenol isomers and bisphenol-A were 73 % and 119 %, respectively, 0.01 mug L-1 and 0.002 mug L-1. The method was applied to the determination of these estrogenic pollutants in river and coastal waters during three months (August-October/1999). The total samples analyzed were 135. Concentrations of 4-nonylphenol isomers and bisphenol-A ranged from 0.03-30 mug L-1 and 0.07-4.0 mug L-1, respectively. Only in two river samples, concentrations of 4-nonylphenol isomers were above 10 mug L-1 and bisphenol-A were above 2 mug L-1. These values can cause estrogenic effects in fish and these sampling points require further investigation in order to verify the maintenance of these levels.

Within-person reproducibility of urinary bisphenol A and phthalate metabolites over a 1 to 3 year period among women in the Nurses’ Health Studies: a prospective cohort study

Townsend, Mary K; Franke, Adrian A; Li, Xingnan; Hu, Frank B; Eliassen, A Heather
Fonte: BioMed Central Publicador: BioMed Central
Tipo: Artigo de Revista Científica
EN_US
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Background: Associations of bisphenol A and phthalates with chronic disease health outcomes are increasingly being investigated in epidemiologic studies. The majority of previous studies of within-person variability in urinary bisphenol A and phthalate metabolite concentrations have focused on reproducibility over short time periods. Long-term reproducibility data are needed to assess the potential usefulness of these biomarkers for prospective studies, particularly those examining risk of diseases with long latency periods. Low within-person reproducibility may attenuate relative risk estimates and reduce statistical power to detect associations with disease. Therefore, we assessed within-person reproducibility of bisphenol A, eight phthalate metabolites, and phthalic acid in spot urine samples over 1 to 3 years among women enrolled in two large cohort studies. Methods: Women in the Nurses’ Health Study and Nurses’ Health Study II provided two spot urine samples, 1 to 3 years apart (n = 80 women for analyses of bisphenol A; n = 40 women for analyses of phthalate metabolites; n = 34 women for analyses of phthalic acid). To measure within-person reproducibility, we calculated Spearman rank correlation coefficients and intraclass correlation coefficients for creatinine-adjusted concentrations of bisphenol A...

Degradation of 4-nonylphenol, 4-t-octylphenol, bisphenol A and triclosan following biosolids addition to soil under laboratory conditions

Langdon, K.; Warne, M.; Smernik, R.; Shareef, A.; Kookana, R.
Fonte: Pergamon-Elsevier Science Ltd Publicador: Pergamon-Elsevier Science Ltd
Tipo: Artigo de Revista Científica
Publicado em //2011 EN
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Land application of biosolids is common practice in many countries, however, there are some potential risks associated with the presence of contaminants within the biosolids. This laboratory study examined the degradation of four commonly found organic compounds, 4-nonylphenol, 4-t-octylphenol, bisphenol A, and triclosan, in soil following the addition of two biosolids over 32 weeks. The pattern of degradation was assessed to determine if it followed a standard first-order decay model or if a biphasic model with a degrading and a recalcitrant fraction better described the data. The time taken for the initial concentrations to decrease by 50% (DT50), based on a first-order model, was 12-25 d for 4-nonylphenol, 10-14 d for 4-t-octylphenol, 18-102 d for bisphenol A, and 73-301 d for triclosan. For 4-nonylphenol, bisphenol A and triclosan, the biphasic model fitted the degradation data better than the first-order model, indicating the presence of a degrading fraction and a non-degrading recalcitrant fraction. The recalcitrant fraction for these three compounds at the completion of the 32 week experiment was 17-21%, 24-42%, and 30-51% of the initial concentrations, respectively. For 4-t-octylphenol, the first-order model was sufficient in explaining the degradation data...

Field dissipation of 4-nonylphenol, 4-t-octylphenol, triclosan and bisphenol A following land application of biosolids

Langdon, K.; Warne, M.; Smernik, R.; Shareef, A.; Kookana, R.
Fonte: Pergamon-Elsevier Science Ltd Publicador: Pergamon-Elsevier Science Ltd
Tipo: Artigo de Revista Científica
Publicado em //2012 EN
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780.1722%
The persistence of contaminants entering the environment through land application of biosolids needs to be understood to assess the potential risks associated. This study used two biosolids treatments to examine the dissipation of four organic compounds: 4-nonylphenol, 4-t-octylphenol, bisphenol A and triclosan, under field conditions in South Australia. The pattern of dissipation was assessed to determine if a first-order or a biphasic model better described the data. The field dissipation data was compared to previously obtained laboratory degradation data. The concentrations of 4-nonylphenol, 4-t-octylphenol and bisphenol A decreased during the field study, whereas the concentration of triclosan showed no marked decrease. The time taken for 50% of the initial concentration of the compounds in the two biosolids to dissipate (DT50), based on a first-order model, was 257 and 248 d for 4-nonylphenol, 231 and 75 d for 4-t-octylphenol and 289 and 43 d for bisphenol A. These field DT50 values were 10- to 20-times longer for 4-nonylphenol and 4-t-octylphenol and 2.5-times longer for bisphenol A than DT50 values determined in the laboratory. A DT50 value could not be determined for triclosan as this compound showed no marked decrease in concentration. The biphasic model provided a significantly improved fit to the 4-t-octylphenol data in both biosolids treatments...

Comparison of degradation between indigenous and spiked bisphenol A and triclosan in a biosolids amended soil

Langdon, K.; Warne, M.; Smernik, R.; Shareef, A.; Kookana, R.
Fonte: Elsevier Science BV Publicador: Elsevier Science BV
Tipo: Artigo de Revista Científica
Publicado em //2013 EN
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767.5313%
This study compared the degradation of indigenous bisphenol A (BPA) and triclosan (TCS) in a biosolids-amended soil, to the degradation of spiked labelled surrogates of the same compounds (BPA-d16 and TCS-(13)C12). The aim was to determine if spiking experiments accurately predict the degradation of compounds in biosolids-amended soils using two different types of biosolids, a centrifuge dried biosolids (CDB) and a lagoon dried biosolids (LDB). The rate of degradation of the compounds was examined and the results indicated that there were considerable differences between the indigenous and spiked compounds. These differences were more marked for BPA, for which the indigenous compound was detectable throughout the study, whereas the spiked compound decreased to below the detection limit prior to the study completion. The rate of degradation for the indigenous BPA was approximately 5-times slower than that of the spiked BPA-d16. The indigenous and spiked TCS were both detectable throughout the study, however, the shape of the degradation curves varied considerably, particularly in the CDB treatment. These findings show that spiking experiments may not be suitable to predict the degradation and persistence of organic compounds following land application of biosolids.; Kate A. Langdon...

Chapel Hill bisphenol A expert panel consensus statement: Integration of mechanisms, effects in animals and potential to impact human health at current levels of exposure

Saal, Frederick S. vom; Akingbemi, Benson T.; Belcher, Scott; Birnbaun, Linda S.; Crain, D. Andrew; Eriksen, Marcus; Farabollini, Francesca; Guillette, Louis J.; Hauser, Russ; Heindel, Jerrold J.; Ho, Shuk-Mei; Hunt, Patricia A.; Iguchi, Taisen; Jobling,
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
ENG
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This document is a summary statement of the outcome from the meeting: ???Bisphenol A: An Examination of the Relevance of Ecological, In vitro and Laboratory Animal Studies for Assessing Risks to Human Health??? sponsored by both the NIEHS and NIDCR at NIH/DHHS, as well as the US-EPA and Commonweal on the estrogenic environmental chemical bisphenol A (BPA, 2,2-bis(4-hydroxyphenyl)propane; CAS# 80-05-7). The meeting was held in Chapel Hill, NC, 28???30 November 2006 due to concerns about the potential for a relationship between BPA and negative trends in human health that have occurred in recent decades. Examples include increases in abnormal penile/urethra development in males, early sexual maturation in females, an increase in neurobehavioral problems such as attention deficit hyperactivity disorder (ADHD) and autism, an increase in childhood and adult obesity and type 2 diabetes, a regional decrease in sperm count, and an increase in hormonally mediated cancers, such as prostate and breast cancers. Concern has been elevated by published studies reporting a relationship between treatment with ???low doses??? of BPA and many of theses negative health outcomes in experimental studies in laboratory animals as well as in vitro studies identifying plausible molecular mechanisms that could mediate such effects. Importantly...

The estrogenicity of bisphenol A-related diphenylalkanes with various substituents at the central carbon and the hydroxy groups

P??rez, Pilar; Pulgar Encinas, Rosa Mar??a; Olea Serrano, F??tima; Villalobos Torres, Mercedes; Rivas, A.; Metzler, Manfred; Pedraza Muriel, Vicente; Olea, Nicol??s
Fonte: National Institute of Environmental Health Publicador: National Institute of Environmental Health
Tipo: Artigo de Revista Científica
ENG
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This work was reported in part at the meeting Estrogens in the Environment IV: Linking Fundamental Knowledge, Risk Assessment, and Public Policy held in Washington, DC, 19-21 July 1997.; The chemical structure of hydroxylated diphenylalkanes or bisphenols consists of two phenolic rings joined together through a bridging carbon. This class of endocrine disruptors that mimic estrogens is widely used in industry, particularly in plastics. Bisphenol F, bisphenol A, fluorine-containing bisphenol A (bisphenol AF), and other diphenylalkanes were found to be estrogenic in a bioassay with MCF7 human breast cancer cells in culture (E-SCREEN assay). Bisphenols promoted cell proliferation and increased the synthesis and secretion of cell type-specific proteins. When ranked by proliferative potency, the longer the alkyl substituent at the bridging carbon, the lower the concentration needed for maximal cell yield; the most active compound contained two propyl chains at the bridging carbon. Bisphenols with two hydroxyl groups in the para position and an angular configuration are suitable for appropriate hydrogen bonding to the acceptor site of the estrogen receptor. Our data suggest that estrogenicity is influenced not only by the length of the substituents at the bridging carbon but also by their nature. Because diphenylalkane derivatives are widespread and their production and use are increasing...

Effect of estradiol and bisphenol A on human hepatoblastoma cell viability and telomerase activity

Xu,B.L.; Zhao,Q.Z.; Gao,X.Y.; Hou,G.J.
Fonte: Associação Brasileira de Divulgação Científica Publicador: Associação Brasileira de Divulgação Científica
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/11/2015 EN
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Sex hormones from environmental and physiological sources might play a major role in the pathogenesis of hepatoblastoma in children. This study investigated the effects of estradiol and bisphenol A on the proliferation and telomerase activity of human hepatoblastoma HepG2 cells. The cells were divided into 6 treatment groups: control, bisphenol A, estradiol, anti-estrogen ICI 182,780 (hereinafter ICI), bisphenol A+ICI, and estradiol+ICI. Cell proliferation was measured based on average absorbance using the Cell Counting-8 assay. The cell cycle distribution and apoptotic index were determined by flow cytometry. Telomerase activity was detected by polymerase chain reaction and a telomeric repeat amplification protocol assay. A higher cell density was observed in bisphenol A (P<0.01) and estradiol (P<0.05) groups compared with the control group. Cell numbers in S and G2/M phases after treatment for 48 h were higher (P<0.05), while the apoptotic index was lower (P<0.05) and telomerase activities at 48 and 72 h (P<0.05) were higher in these groups than in the control group. The cell density was also higher in bisphenol A+ICI (P<0.01) and estradiol+ICI (P<0.05) groups compared with the ICI group. Furthermore, cell numbers were increased in S and G2/M phases (P<0.05)...

Why Public Health Agencies cannot depend on good laboratory practices as a criterion for selecting data: the case of bisphenol A

Myers, John Peterson; Saal, Frederick S. vom; Akingbemi, Benson T.; Arizono, Koji; Belcher, Scott; Colborn, Theo; Chahoud, Ibrahim; Crain, D. Andrew; Farabollini, Francesca; Guillette, Louis J.; Hassold, Terry; Ho, Shuk-Mei; Hunt, Patricia A.; Iguchi, Tai
Fonte: National Institute of Environmental Health Sciences Publicador: National Institute of Environmental Health Sciences
Tipo: Artigo de Revista Científica
ENG
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This is an Open Access article: verbatim copying and redistribution of this article are permitted in all media for any purpose, provided this notice is preserved along with the article's original DOI.; BACKGROUND In their safety evaluations of bisphenol A (BPA), the U.S. Food and Drug Administration (FDA) and a counterpart in Europe, the European Food Safety Authority (EFSA), have given special prominence to two industry-funded studies that adhered to standards defined by Good Laboratory Practices (GLP). These same agencies have given much less weight in risk assessments to a large number of independently replicated non-GLP studies conducted with government funding by the leading experts in various fields of science from around the world. OBJECTIVES We reviewed differences between industry-funded GLP studies of BPA conducted by commercial laboratories for regulatory purposes and non-GLP studies conducted in academic and government laboratories to identify hazards and molecular mechanisms mediating adverse effects. We examined the methods and results in the GLP studies that were pivotal in the draft decision of the U.S. FDA declaring BPA safe in relation to findings from studies that were competitive for U.S. National Institutes of Health (NIH) funding...

Determination of bisphenol A and related aromatic compounds released from bis-GMA-based composites and sealants by high performance liquid chromatography

Pulgar Encinas, Rosa Mar??a; Olea Serrano, F??tima; Novillo-Fertrell, Arancha; Rivas, A.; Pazos, Patricia; Pedraza Muriel, Vicente; Navajas, Jos?? M.; Olea, Nicol??s
Fonte: National Institute of Environmental Health Sciences Publicador: National Institute of Environmental Health Sciences
Tipo: Artigo de Revista Científica
ENG
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'Reproduced with permission from Environmental Health Perspectives'; Most of the composites and sealants used in dentistry are based on bisphenol A diglycidylether methacrylate (Bis-GMA). Reports revealed that in situ polymerization is not complete and that free monomers can be detected by different analytic methods. Concerns about the estrogenicity of bisphenol A (BPA) and other aromatic components leached from commercial products have been expressed. We studied biphenolic components eluted from seven composites and one sealant before and after in vitro polymerization using HPLC and gas chromatography/mass spectrometry and we investigated how pH modifications affect the leaching of these components. We found BPA (maximal amount 1.8 microg/mg dental material), its dimethacrylate derivative (Bis-DMA, 1.15 microg/mg), bisphenol A diglycidylether (6. 1 microg/mg), Bis-GMA (2.0 microg/mg), and ethoxylate and propoxylate of bisphenol A in media in which samples of different commercial products were maintained under controlled pH and temperature conditions. Our results confirm the leaching of estrogenic monomers into the environment by Bis-GMA-based composites and sealants in concentrations at which biologic effects have been demonstrated in in vivo experimental models. The main issue with implications for patient care and dentist responsibility is to further determine the clinical relevance of this estrogenic exposure.

Analysis of bisphenol A in natural waters by means of an optical immunosensor

Rodríguez-Mozaz, Sara; López de Alda, Miren; Barceló, Damià
Fonte: Elsevier Publicador: Elsevier
Tipo: Artículo Formato: 22195 bytes; application/pdf
ENG
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9 pages, 3 figures.-- PMID: 16337256 [PubMed].-- Printed version published Dec 2005.; This work describes a very simple, fast and sensitive method based on the use of the optical immunosensor “RIver ANAlyser” (RIANA) to the determination of bisphenol A in a waters. RIANA is based on a rapid solid-phase indirect inhibition immunoassay that takes place at an optical transducer chip chemically modified with an analyte derivative. Fluorescence produced by labelled antibodies bound to the transducer is detected by photodiodes and can be correlated with the analyte concentration. The sensor surface can be regenerated thus allowing the performance of several measurements (around 300) with the same transducer. Each test cycle, including one regeneration step, is accomplished in 15 min. The detection limit achieved in the direct determination of bisphenol A in water with this system was 0.014 μg/L. Satisfactory repeatability, with relative standard deviations (RSD) ranging between 1.48% and 6.93% were obtained. The immunosensor method developed was applied to the monitoring of bisphenol A in various types of water collected in a waterworks (from the river water source to the finished drinking water) and validated against the results obtained in the same approach by a more traditional method...

Monitoring of estrogens, pesticides and bisphenol A in natural waters and drinking water treatment plants by solid-phase extraction–liquid chromatography–mass spectrometry

Rodríguez-Mozaz, Sara; López de Alda, Miren; Barceló, Damià
Fonte: Elsevier Publicador: Elsevier
Tipo: Artículo Formato: 22195 bytes; application/pdf
ENG
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8 pages, 6 tables.-- PMID: 15378882 [PubMed].-- Printed version published Aug 6, 2004.-- Presented at the 3rd Meeting of the Spanish Association of Chromatography and Related Techniques and the European Workshop: 3rd Waste Water Cluster, Aguadulce (Almeria), Spain, Nov 19–21, 2003.; A multi-residue analytical method has been developed for the determination of various classes of selected endocrine disruptors. This method allows the simultaneous extraction and quantification of different estrogens (estradiol, estrone, estriol, estradiol-17-glucuronide, estradiol diacetate, estrone-3-sulfate, ethynyl estradiol and diethylstilbestrol), pesticides (atrazine, simazine, desethylatrazine, isoproturon and diuron), and bisphenol A in natural waters. In the method developed, 500 ml of water are preconcentrated on LiChrolut RP-18 cartridges. Further analysis is carried out by liquid chromatography–mass spectrometry (LC–MS) using atmospheric pressure chemical ionisation (APCI) in the positive ion mode for determination of pesticides and electrospray in the negative ionisation mode for determination of estrogens and bisphenol A. Recoveries for most compounds were between 90 and 119%, except for bisphenol A (81%) and diethylstilbestrol (70%)...

Occurrence of Nonylphenol and Bisphenol-A in Surface Waters from Portugal

Azevedo, Débora de A.; Lacorte Bruguera, Silvia; Viana, Paula; Barceló, Damià
Fonte: Sociedade Brasileira de Química Publicador: Sociedade Brasileira de Química
Tipo: Artículo
ENG
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The occurrence of the endocrine disruptor compounds, such as 4-nonylphenol isomers and bisphenol A was determined in surface water samples from Portugal. The analytical method used involved the preconcentration of 200 mL of water sample by solid phase extraction (SPE) using a OASIS (Waters) cartridge, followed by Gas Chromatography-Mass Spectrometry (GC/MS) determination. Recoveries and limits of detection of 4-nonylphenol isomers and bisphenol-A were 73 % and 119 %, respectively, 0.01 mg L-1 and 0.002 mg L-1. The method was applied to the determination of these estrogenic pollutants in river and coastal waters during three months (August-October/1999). The total samples analyzed were 135. Concentrations of 4-nonylphenol isomers and bisphenol-A ranged from 0.03-30 mg L-1 and 0.07-4.0 mg L-1, respectively. Only in two river samples, concentrations of 4-nonylphenol isomers were above 10 mg L-1 and bisphenol-A were above 2 mg L-1. These values can cause estrogenic effects in fish and these sampling points require further investigation in order to verify the maintenance of these levels.; D. A. A. acknowledges a grant from CNPq. Direção Geral do Ambiente, Ministério do Ambiente (Portugal), the EU project of the waste water cluster SANDRINE (ENV4-CT98-0801) and CICYT (AMB/999-1705-CE) are acknowledged for financial support to this project. Rosa Alonso and Roser Chaler are acknowledged for technical assistance.; Peer reviewed

Simultaneous Determination of Bisphenol A and Bisphenol S in Environmental Water using Ratio Derivative Ultraviolet Spectrometry

Cao,Guiping; Zhuang,Yafeng; Liu,Baoliang
Fonte: South African Journal of Chemistry Publicador: South African Journal of Chemistry
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2014 EN
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677.8572%
A simplified method based on ratio derivative ultraviolet spectrometry for simultaneous determination of bisphenol A (BPA) and bisphenol S (BPS) in environmental water is presented. The method provides a direct analysis of the samples without tedious sample preparation. In this method, the overlapping spectra of BPA and BPS were well resolved using the first derivative (Δλ = 1 nm) of the ratio of their absorption spectra. Measurements of absorbance were performed at wavelengths of 229.5 nm and 245.5 nm for BPA and BPS, respectively, using the ratio derivative spectrum method. Beer's law was followed in the concentration range of 8.8 X 10-7-2.2 X 10-4 mol dm-3 for BPA and 1.4 X 10-6-1.0 X 10-4 mol dm-3 for BPS. The limits of detection were 3.5 X -7 mol dm-3 for BPA and 4.4 X 10 7 mol dm ³ for BPS. Their 5:1 to 1:5 mixtures were resolved with recoveries between 90.5 % and 100.9 % for BPA and between 93.8 % and 101.1 % for BPS. The method was satisfactorily applied to the simultaneous determination of BPA and BPS in environmental water samples.

Evaluation of blood Bisphenol A contents: a case study

Taskeen,A; Naeem,I; Atif,M
Fonte: West Indian Medical Journal Publicador: West Indian Medical Journal
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2012 EN
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OBJECTIVE: It has been recently reported that Bisphenol A (BPA) may leach out into food, beverages and water samples from the plastic ware in which it is stored. Serious health hazards have been reported from BPA. The purpose of this study is to assess the BPA contents in blood and to assess the risk of cancer. METHOD: A total of 100 individuals were selected for study according to the following five age groups: 5-10, 11-20, 21-30, 31-40 and 41-50 years. They were then further divided into normal and diseased. Age, gender, education, source of drinking water, type of food, smoking habit, any exposure to chemicals and history of cancer were elicited during interview. Blood samples were collected and processed for analysis using reversed phase-high performance liquid chromatography (rp-HPLC) in isocratic mode. The mobile phase consisted of acetonitrile and water (1:1) at a flow-rate of 1 ml min-1. RESULTS: Bisphenol A contents found in blood samples of all age groups ranged from 1.53-3.98 (mean = 2.94, SD = 0.9). P-values, for the exposed people and those having a history of cancer, were < 0.05 showing a significant relationship between BPA and cancer. The United States Environmental Protection Agency (US EPA) has established a reference dose of 50 µg/L. Odd ratios and relative risk for smoking habit were < 1 while for all others they were > 1. CONCLUSION: It was concluded from the study that people using bottled water...