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1.
Food Chem ; 213: 274-283, 2016 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-27451182

RESUMO

Endocrine activity of drinking water is a matter of growing interest for scientists as well as health authorities. A concentration technique for endocrine activity screening was developed, optimized, and transposed from 200mL to 10L water samples. To avoid any contamination during concentration, the method was developed using exclusively glass, Teflon and stainless steel materials. Any potential losses were tracked using three model radiolabeled molecules, namely BPA, DEHP and 4n-NP. The final method allowed 10L water samples to be concentrated 5000-fold, with good recovery and repeatability. After validation, by concentrating spiked and non-spiked 10L samples of EVIAN natural mineral water, 14 different drinking water samples were concentrated and screened for endocrine disrupting activity using bioluminescent assays. Samples consisting of bottled water, conditioned in various materials (glass, PET) and subjected to different storage conditions, had no hormone-like activities whereas estrogenic activity was found in the filtered tap water.


Assuntos
Água Potável/química , Disruptores Endócrinos/análise , Águas Minerais , Estrona , Medições Luminescentes
2.
Sci Total Environ ; 443: 621-32, 2013 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-23220754

RESUMO

The aim of this work was to investigate the potential presence of a broad range of organic compounds, such as hormones, alkylphenols, bisphenol A and phthalates, as well as pharmaceutical substances in two brands of bottled natural mineral waters (Evian and Volvic, Danone). The phthalates were determined by solid-phase microextraction coupled to gas chromatography-mass spectrometry (SPME-GC-MS) and the other compounds by liquid chromatography-tandem mass spectrometry (LC-MS/MS) or gas chromatography-mass spectrometry (GC-MS) after solid-phase extraction. The potential migration of alkylphenols, bisphenol A and phthalates from polyethylene terephthalate (PET) bottles was also investigated under standardized test conditions. Evian and Volvic natural mineral waters contain none of the around 120 targeted organic compounds. Traces of 3 pharmaceuticals (ketoprofen, salicylic acid, and caffeine), 3 alkylphenols (4-nonylphenol, 4-t-octylphenol, and 4-nonylphenol diethoxylate), and some phthalates including di(2-ethylhexyl)phthalate (DEHP) were detected in the samples, but they were also present in the procedural blanks at similar levels. The additional test procedures demonstrated that the few detected compounds originated from the background laboratory contamination. Analytical procedures have been designed both in the bottling factory and in the laboratory in order to investigate the sources of DEHP and to minimize to the maximum this unavoidable laboratory contamination. It was evidenced that no migration of the targeted compounds from bottles occurred under the test conditions. The results obtained in this study underline the complexity of reaching a reliable measure to qualify the contamination of a sample at ultra-trace level, in the field of very pure matrices. The analytical procedures involving glassware, equipment, hoods, and rooms specifically dedicated to trace analysis allowed us to reach reliable procedural limits of quantification at the ng/L level, by lowering the background laboratory contamination.


Assuntos
Hormônios/análise , Águas Minerais/análise , Preparações Farmacêuticas/análise , Fenóis/análise , Ácidos Ftálicos/análise , Cromatografia Líquida , França , Cromatografia Gasosa-Espectrometria de Massas , Controle de Qualidade , Extração em Fase Sólida , Espectrometria de Massas em Tandem
3.
Chemosphere ; 88(1): 131-9, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22475153

RESUMO

We surveyed four different river systems in the Greater Montreal region, upstream and downstream of entry points of contamination, from April 2007 to January 2009. The studied compounds belong to three different groups: PPCPs (caffeine, carbamazepine, naproxen, gemfibrozil, and trimethoprim), hormones (progesterone, estrone, and estradiol), and triazine herbicides and their metabolites (atrazine, deethylatrazine, deisopropylatrazine, simazine, and cyanazine). In the system A, B, and C having low flow rate and high TOC, we observed the highest detection frequencies and mass flows of PPCPs compared to the other compounds, reflecting discharge of urban contaminations through WWTPs and CSOs. However, in River D, having high flow rate and low TOC, comparable frequency of detection of triazine and their by-products and PPCPs, reflecting cumulative loads of these compounds from the Great Lakes as well as persistency against natural attenuation processes. Considering large differences in the removal efficiencies of caffeine and carbamazepine, a high ratio of caffeine/carbamazepine might be an indicative of a greater proportion of raw sewage versus treated wastewater in surface waters. In addition, caffeine appeared to be a promising indicator of recent urban fecal contaminations, as shown by the significant correlation with FC (R(2)=0.45), while carbamazepine is a good indicator of cumulative persistence compounds.


Assuntos
Cafeína/análise , Água Potável/química , Monitoramento Ambiental , Fezes/química , Preparações Farmacêuticas/análise , Poluentes Químicos da Água/análise , Canadá , Disruptores Endócrinos/análise , Herbicidas/análise , Herbicidas/metabolismo , Lagos , Rios/química
4.
J Mass Spectrom ; 46(4): 383-90, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21438088

RESUMO

The applicability of three different ionization techniques: atmospheric pressure photoionization (APPI), atmospheric pressure chemical ionization (APCI) and electrospray ionization (ESI) was tested for the liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis of five target pharmaceuticals (cyclophosphamide, methotrexate, bezafibrate, enalapril and orlistat) in wastewater samples. Performance was compared both by flow injection analysis (FIA) and on-column analysis in deionized water and wastewater samples. A column switching technique for the on-line extraction and analysis of water samples was used. For both FIA and on-column analysis, signal intensity and signal-to-noise (S/N) ratio of the target analytes in the three sources were studied. Limits of detection and matrix effects during the analysis of wastewater samples were also investigated. ESI generated significantly larger peak areas and higher S/N ratios than APCI and APPI in FIA and in on-column analysis. ESI was proved to be the most suitable ionization method as it enabled the detection of the five target compounds, whereas APCI and APPI ionized only four compounds.


Assuntos
Bezafibrato/análise , Ciclofosfamida/análise , Enalapril/análise , Lactonas/análise , Espectrometria de Massas/métodos , Metotrexato/análise , Poluentes Químicos da Água/análise , Bezafibrato/química , Cromatografia Líquida/métodos , Ciclofosfamida/química , Enalapril/química , Análise de Injeção de Fluxo , Lactonas/química , Metotrexato/química , Orlistate , Esgotos/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos , Água/química , Poluentes Químicos da Água/química
5.
J Environ Monit ; 13(3): 583-90, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21206945

RESUMO

The development of a high-throughput method for the analysis of 14 endocrine-disrupting substances in environmental solid matrices has been investigated. Selected compounds were: hormones (estrogens and progestogens), parabens and triclocarban. The ultrafast method (15 s per sample) is based on the laser diode thermal desorption-atmospheric pressure chemical ionization (LDTD-APCI) coupled to tandem mass spectrometry (MS/MS). This novel approach was tested and validated in three different solid matrices (municipal sludge cakes, aquatic sediments and agricultural soils) and its performance was evaluated by estimation of extraction recovery, linearity, precision, and detection limits. In contrast to other methods based on LC-MS/MS, a cleanup step is not necessary or minimal for the municipal sludge cake matrix. Extraction recoveries ranged from 80 to 109% for all compounds in all matrix types except for estriol which was 60-75%. The intra- and inter-day precisions, as indicated by % RSD, were ≤ 14% and ≤ 16%, respectively. The method detection limits ranged from 0.7 to 4.0 ng g⁻¹ in sediments and soil matrices and 2.8 to 16.8 ng g⁻¹ for municipal sludge cake samples. The results for real environmental samples collected in different areas of Quebec (Canada) are illustrated.


Assuntos
Disruptores Endócrinos/análise , Monitoramento Ambiental/métodos , Sedimentos Geológicos/análise , Lasers Semicondutores , Esgotos/análise , Solo/análise , Espectrometria de Massas em Tandem
6.
J Chromatogr A ; 1216(48): 8518-27, 2009 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-19875124

RESUMO

We describe the development and validation of an on-line solid-phase extraction of large-volume injections coupled to liquid chromatography-tandem mass spectrometry method for the simultaneous quantitation and confirmation of 14 selected trace organic contaminants in drinking and surface water. Selected compounds were: anti-infectives (clarithromycin, sulfamethoxazole and trimethoprim), an anticonvulsant (carbamazepine) and its transformation product 10,11-dihydrocarbamazepine, an antihypertensive (enalapril), antineoplastics (cyclophosphamide and methotrexate), herbicides (atrazine, cyanazine, and simazine) and two of their transformation products (deethylatrazine and deisopropylatrazine) and an antiseptic (triclocarban). The breakthrough volume determinations showed that out of all the investigated sorbents, the Strata-X on-line solid-phase extraction column showed the best performance. The method used a load volume of 10.0 mL and was validated using the corresponding matrices, yielding for most compounds, R(2)>0.99. Extraction recoveries ranged from 60 to 109%. The intra- and inter-day precision were <14 and <16%, respectively. The method detection limits ranged from 0.6 to 6 ng L(-1). Matrix effects were in general low. The performance of the on-line method was demonstrated with the analysis of real water samples. The application of alternative techniques of confirmation was also explored using accurate mass measurements on a time-of-flight mass spectrometer and the data-dependent reverse energy ramp scan on a triple quadrupole.


Assuntos
Cromatografia Líquida/métodos , Sistemas On-Line/instrumentação , Compostos Orgânicos/análise , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos , Poluentes Químicos da Água/análise , Abastecimento de Água/análise , Canadá , Limite de Detecção , Praguicidas/análise , Preparações Farmacêuticas/análise , Reprodutibilidade dos Testes , Rios/química , Propriedades de Superfície
7.
J Environ Monit ; 10(4): 482-9, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18385869

RESUMO

A simple on-line method was developed for the analysis of pharmaceuticals, pesticides and some metabolites in drinking, surface and wastewater samples. The technique is based on the use of on-line solid-phase extraction combined with liquid chromatography electrospray tandem mass spectrometry with positive electrospray ionization (LC-ESI(PI)-MS/MS). The injection of only 1 mL of filtered water sample is used with a total analysis time of 20 min, including the period required to flush the SPE cartridge with organic solvent and reconditioning the LC column. Method detection limits were in the range of 2 to 24 ng L(-1) for the compounds of interest, with recoveries from 87 to 110% in surface as well as wastewater samples. Matrix effects were observed for some compounds without exceeding more than 25%. All results displayed a good degree of reproducibility, with relative standard deviations (RSD) of less than 12% for all compounds. Moreover, at least 200 samples were analyzed without altering the performance of the pre-concentration column. This method was preferred over traditional off-line procedures because it minimizes tedious sample preparation, increases productivity and sample throughput. The analysis of various water and wastewater samples showed that caffeine, carbamazepine and atrazine could be detected in all the samples analysed and the selected compounds are always present in at least one of the sample types.


Assuntos
Água Doce/análise , Praguicidas/análise , Preparações Farmacêuticas/análise , Esgotos/análise , Poluentes Químicos da Água/análise , Abastecimento de Água , Canadá , Cromatografia Líquida , Estrutura Molecular , Extração em Fase Sólida , Espectrometria de Massas em Tandem , Abastecimento de Água/normas
8.
Environ Toxicol Chem ; 23(11): 2673-81, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15559283

RESUMO

An exhaustive study of the distribution of butyltin species was conducted in the sediment of the Saguenay Fjord (Canada), a semi-enclosed marine system with sediment permanently submitted to sub-Arctic cold conditions. Concentrations of total butyltins (tributyltin [TBT], dibutyltin, and monobutyltin) ranged from 6 to 288 ng Sn/g dry weight and were typical of those reported for contaminated coastal areas despite limited seasonal traffic of commercial vessels in the fjord. The distribution profiles of butyltin species in four sediment cores clearly indicated the high persistence of TBT that was dominating other species. The particular oceanographic conditions of the Saguenay Fjord (low seawater temperature, anoxic sediments, and low exchange rate of deep waters) combined with a high sediment/pore-water partition coefficient (Kdobs = 1.0 x 10(4) to 1.2 x 10(4) L/kg) and a low sediment/ water diffusive flux of TBT (J1 = 13 x 10(-8) mol/m2/year) are responsible for the burial and preservation of TBT in this marine ecosystem. The half-life of TBT in deep sediment was estimated to be approximately 87+/-17 years (+/-SEM), which implies a much slower degradation rate than any previously reported. Finally, a flood event that occurred five years before the sampling enabled us to calculate a very slow diffusive flux from the preflood to the postflood layer (J2 = 2 x 10(-8) mol/m2/year), indicating an almost permanent sequestration of TBT in the buried layers.


Assuntos
Sedimentos Geológicos/análise , Compostos Orgânicos de Estanho/análise , Compostos de Trialquitina/análise , Poluentes Químicos da Água/análise , Canadá , Ecossistema , Monitoramento Ambiental/legislação & jurisprudência , Meia-Vida , Compostos Orgânicos de Estanho/química , Pintura/análise , Solubilidade , Compostos de Trialquitina/química , Água/análise
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