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1.
Environ Pollut ; 115(2): 291-301, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11706802

RESUMEN

Nine structurally different phenolic chemicals, which have been reported to mimic estrogen effects, were determined in various aquatic environmental compartments. Twenty-three water samples from five streams and rivers showed levels up to 458 ng/l for 4-nonylphenol (4NP), 189 ng/l for 4-t-octylphenol (4tOP), 272 ng/l for bisphenol A (BPA) and 47 ng/l for 2-hydroxybiphenyl (2OHBiP). Elevated levels of these compounds in a stream with a high load of effluents of sewage treatment plants (STPs), compared to a brook free of sewage, identified STPs as major sources. With a similar order, 4NP (10-259 micrograms/kg dry matter), 4tOP (< 0.5-8 micrograms/kg), BPA (< 0.5-15 micrograms/kg), and 2OHBiP (2-69 micrograms/kg) were also detected regularly in riverine sediment (n = 11). Levels in sewage sludge were one order of magnitude higher than in sediments. 4-Hydroxybiphenyl and 4-chloro-3-methylphenol were found predominantly in sludge and sediment in the lower ppb range.


Asunto(s)
Estrógenos no Esteroides/análisis , Agua Dulce/química , Fenoles/análisis , Aguas del Alcantarillado/química , Contaminantes Químicos del Agua/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Sedimentos Geológicos , Alemania , Reproducibilidad de los Resultados
2.
Chemosphere ; 40(9-11): 929-35, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10739028

RESUMEN

A simple and sensitive GC/MS method for the quantitative determination of the estrogenic phenolic compounds 4-nonylphenol, 4-t-octylphenol, bisphenol A, 3-t-butyl-4-hydroxyanisole, 2-t-butyl-4-methylphenol, 4-hydroxybiphenyl, 2-hydroxybiphenyl, 4-chloro-3-methylphenol, and 4-chloro-2-methylphenol in aquatic samples was developed. The method for assessing their occurrence in sewage, surface and drinking waters consists of solid phase extraction (SPE) using a polystyrene copolymer phase. After methylation of the extract HRGC/LRMS analysis was possible without any clean up, even in raw sewage samples. Limits of detection and determination were between <0.01 and 0.05 ng/l and 0.01 and 0.05 ng/l, respectively. Recoveries were above 70% with exception of 3-t-butyl-4-hydroxyanisole.


Asunto(s)
Estrógenos/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Fenoles/análisis , Agua/química , Xenobióticos/análisis , Sensibilidad y Especificidad , Aguas del Alcantarillado/análisis
3.
Chemosphere ; 40(9-11): 1131-42, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10739055

RESUMEN

24 h samples of untreated and treated wastewater were taken in parallel from a modern municipal sewage plant in southern Germany in March and June 1998. After solid phase extraction, total estrogenic activity was quantitatively measured with a miniaturized E-screen assay and the levels of nine estrogenic phenolic chemicals analyzed by HRGC/LRMS. 17Beta-estradiol equivalent concentrations (EEQ) were 58 and 70 ng/l in the influent and 6 ng/l in the effluent, indicating that the load of estrogenic activity of the wastewater was reduced by about 90% in the sewage plant. Less than 3% of the estrogenic activity was found in the sludge. 4-t-octylphenol, 4-nonylphenol, bisphenol A, 2-hydroxybiphenyl, and 4-chloro-3-methylphenol were detected in the untreated wastewater at levels from 0.13 to 3.6 microg/l. 4-t-octylphenol, 4-nonylphenol, and bisphenol A were present in the effluent at concentrations from 0.16 to 0.36 microg/l, 2-hydroxybiphenyl and 4-chloro-3-methylphenol were not detectable. The contribution of the quantified levels of phenolic xenoestrogens to total estrogenic activity in the sewage was 0.7-4.3%.


Asunto(s)
Estrógenos/análisis , Fenoles/análisis , Aguas del Alcantarillado/análisis , Compuestos de Bencidrilo , Compuestos de Bifenilo/análisis , Neoplasias de la Mama/patología , División Celular/efectos de los fármacos , Estradiol/farmacología , Estrógenos/farmacología , Cromatografía de Gases y Espectrometría de Masas , Alemania , Humanos , Fenoles/farmacología , Células Tumorales Cultivadas
4.
Environ Toxicol Chem ; 20(10): 2142-51, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11596742

RESUMEN

The proliferation test with human estrogen receptor-positive MCF-7 breast cancer cells (E-Screen assay) was applied for quantitative determination of total estrogenic activity in 24-h composite effluent samples from 16 municipal and two industrial sewage treatment plants (STPs) in the state of Baden-Württemberg, southwestern Germany. The estrogenic efficacy relative to the positive control, 17beta-estradiol, was between 26 and 74% (median, 48%) for the 16 municipal STPs. Estradiol equivalent concentrations (EEQs) were between 0.2 and 7.8 ng/L (median, 1.6 ng/L) and, thereby, were lower than those found in a pilot study, which revealed EEQs of greater than 10 ng/L in the effluents of two other STPs. The EEQs in 14 of the 16 effluent samples were very similar (0.9-3.3 ng/L), indicating a rather constant input of estrogenic substances via STPs into rivers. Additional activated charcoal filtration turned out to be very efficient in further eliminating estrogenic activity from effluents. The EEQs of the E-Screen assay and those calculated from the results of extensive chemical analysis using the estradiol equivalency factors determined for 13 natural and synthetic estrogenic substances were comparable for most of the effluent samples. 17beta-Estradiol, 17alpha-ethinylestradiol, and, to a lesser extent, estrone contributed to 90% or more of the EEQ value.


Asunto(s)
Estrógenos/análisis , Estrógenos/farmacología , Receptores de Estrógenos/fisiología , Aguas del Alcantarillado/química , Carbón Orgánico , Femenino , Filtración , Humanos , Industrias , Células Tumorales Cultivadas , Eliminación de Residuos Líquidos , Purificación del Agua
5.
Dtsch Zahnarztl Z ; 33(9): 594-8, 1978 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-100304

RESUMEN

The operative procedure for partially replacing the root with A12O3 ceramic represents a good possibility for preserving teeth in which the pulpa is devitalized. The method used in connection with the well known autoplastic reimplantation not only presents an alternative to the traditional apicoectomy but also provides additional stabilization of the tooth by lengthing the root with cocotostabile and biocompatible A1203 ceramic. The method was tested in humans and monkeys. Argumentation was based on histological examination via light microscopy.


Asunto(s)
Reimplante Dental/métodos , Óxido de Aluminio , Animales , Materiales Biocompatibles , Desvitalización de la Pulpa Dental , Haplorrinos , Humanos , Raíz del Diente
6.
Chem Res Toxicol ; 13(12): 1214-22, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11123961

RESUMEN

The use of recycled paper for the manufacture of food contact materials is widespread, but very little is known about the presence of potential contaminants in the paper. The purpose of this study was to assess the worst-case migration of estrogenic active compounds using extracts of paper for household use. Twenty different brands of kitchen rolls, nine of which were made from recycled paper and the remainder from virgin paper, were obtained from retail shops. Paper extracts were subjected to (a) determination of the total estrogenic activity by using an in vitro estrogen screen based on yeast cells stably transfected with the human estrogen receptor alpha and (b) chemical analysis and quantification by GC/MS, GC/FTIR/MS, and GC/FID for detection of a variety of estrogenic compounds. A marked estrogenic response was observed in nine of the extracts, seven of which were made from recycled paper and two from virgin paper. The chemical analysis revealed that extracts made from recycled paper contained levels of bisphenol A ranging from 0.6 to 24 mg/kg of kitchen roll, whereas extracts from virgin paper contained no bisphenol A or only negligible amounts. In contrast, 4-tert-octylphenol, 4-nonylphenols, and di-n-butyl and diisobutyl phthalate were present to a varying degree in both recycled and virgin paper with no apparent preferable distribution between the two paper types. The estrogenic response of the two extracts made from virgin paper appeared to be due partly to the presence of the preservative propyl paraben. Diisopropylnaphthalene, which turned out to be weakly estrogenic active in vitro (EC(50) = 53 microM), was detected in minor amounts in most of the extracts with the major part, ranging from 0.3 to 4.7 mg/kg of paper, found in recycled paper. Our findings that recycled kitchen rolls contain bisphenol A and other xenoestrogens may apply to other types of recycled paper used for food packaging and emphasize the importance of identifying this and other contaminants in recycled paper in general. These data indicate that bisphenol A may be useful as a purity indicator for recycled paper.


Asunto(s)
Equipo Reutilizado , Estrógenos no Esteroides/análisis , Productos Domésticos , Papel , Compuestos de Bencidrilo , Antagonistas de Estrógenos/análisis , Antagonistas de Estrógenos/farmacología , Estrógenos no Esteroides/farmacología , Cromatografía de Gases y Espectrometría de Masas , Técnicas In Vitro , Parabenos/análisis , Fenoles/análisis , Receptores de Estrógenos/efectos de los fármacos , Receptores de Estrógenos/genética , Saccharomyces cerevisiae/efectos de los fármacos , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Transfección
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