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1.
J Chromatogr A ; 1466: 136-47, 2016 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-27623063

RESUMEN

Fatty acid esters of 3-monochloro-1,2-propanediol (3-MCPDEs), of 2-monochloro-1,3-propanediol (2-MCPDEs) and of 2,3-epoxy-1-propanol or glycidol (GEs), which are considered to be deleterious to human health, may occur in a broad variety of food samples. A proper risk assessment of those substances requires the availability of robust occurrence data; in this respect concerns have been raised regarding the reliability of results obtained with the currently available methods to determine those substances in processed food. This article presents an indirect analytical procedure for the simultaneous determination of 3-MCPDEs, 2-MCPDEs and GEs in a wide variety of food products after extraction by pressurised liquid extraction (PLE) and determination by gas chromatography mass-spectrometry (GC-MS). For the differentiation of MCPDEs and GEs, the latter were first converted to monobromopropanediol esters (MBPDEs) in acid aqueous solution of sodium bromide. MCPDEs and MBPDEs were then hydrolysed under acidic conditions followed by derivatisation of the released free (non-esterified) form in ethyl acetate with phenyl boronic acid (PBA). Quantification of the analytes was carried out using the isotopic labelled analogues of both MCPDEs and GEs. Limits of detection (LODs) and limits of quantitation (LOQs) were in the range of 7-17mgkg(-1) and 13-31mgkg(-1) respectively, while the working range of the method was between LOQ and 1850mgkg(-1) expressed on fat basis. The developed method was successfully applied for the analysis of the target compounds in more than 650 different food samples covering the following commodities: bread and rolls, fine bakery wares, smoked fish products, fried and roasted meat, potato based snacks and fried potato products, cereal-based snacks and margarines.


Asunto(s)
Ésteres/análisis , Análisis de los Alimentos/métodos , Contaminación de Alimentos/análisis , Glicerol/análogos & derivados , Animales , Ácidos Grasos/análisis , Productos Pesqueros/análisis , Cromatografía de Gases y Espectrometría de Masas , Glicerol/análisis , Límite de Detección , Carne/análisis , Reproducibilidad de los Resultados
2.
Bioresour Technol ; 162: 365-72, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24768891

RESUMEN

The removal of endocrine disrupting compounds (EDCs) and non-steroidal anti-inflammatory drugs (NSAIDs) was studied in three lab-scale anaerobic digestion (AD) systems; a single-stage mesophilic, a single-stage thermophilic and a two-stage thermophilic/mesophilic. All micropollutants underwent microbial degradation. High removal efficiency (>80%) was calculated for diclofenac, ibuprofen, naproxen and ketoprofen; whereas triclosan, bisphenol A and the sum of nonylphenol (NP), nonylphenol monoethoxylate (NP1EO) and nonylphenol diethoxylate were moderately removed (40-80%). NSAIDs removal was not affected by the type of AD system used; whereas slightly higher EDCs removal was observed in two-stage system. In this system, most microcontaminants were removed in thermophilic digester. Biotransformation of NP1EO and NP was affected by the temperature applied to bioreactors. Under mesophilic conditions, higher removal of NP1EO and accumulation of NP was noticed; whereas the opposite was observed under thermophilic conditions. For most analytes, higher specific removal rates were calculated under thermophilic conditions and 20 days SRT.


Asunto(s)
Aguas del Alcantarillado/microbiología , Temperatura , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua/métodos , Anaerobiosis , Antiinflamatorios no Esteroideos/aislamiento & purificación , Biodegradación Ambiental , Biocombustibles , Reactores Biológicos/microbiología , Disruptores Endocrinos/aislamiento & purificación , Fenoles/aislamiento & purificación , Purificación del Agua/instrumentación
3.
Sci Total Environ ; 463-464: 1067-75, 2013 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-23891999

RESUMEN

The occurrence and fate of 36 emerging contaminants, belonging to five different classes, (benzotriazoles, BTRs; benzothiazoles, BTHs; perfluorinated compounds, PFCs; non-steroidal anti-inflammatory drugs, NSAIDs and endocrine disruptors, EDCs) were investigated in raw, treated wastewater (both particulate and dissolved phases), and in sludge from a sewage treatment plant (STP) in Athens, Greece. The average concentrations of BTRs, BTHs, NSAIDs and EDCs in raw wastewater ranged between 11 ng L(-1) and 7.27 µg L(-1), while PFCs did not exceed 100 ng L(-1). In dewatered sludge, the average concentrations ranged between 0.8 ng g(-1) dw (perfluorohexanoic acid, PFHxA) and 3895 ng g(-1) dw (nonylphenol, NP). The distribution of emerging contaminants between particulate and dissolved phase was different among the compounds. BTRs and BTHs showed lower solid-liquid distribution coefficients (Kd) than all other compounds. For 9 over the 27 compounds detected in influents, the removal efficiency was higher than 70%, while the others either were removed to a lesser extent or detected at higher concentrations in effluents. Based on this, advanced treatment processes should be applied in the future for achieving adequate emerging contaminants removal in STPs. Regarding removal mechanisms, almost 60% of BTRs and 30 to 75% of BTHs were removed in bioreactors, while the contribution of primary and secondary clarifiers was of minor importance. Sorption to primary sludge was a significant mechanism affecting EDCs fate in STP.


Asunto(s)
Benzotiazoles/análisis , Disruptores Endocrinos/análisis , Preparaciones Farmacéuticas/análisis , Aguas del Alcantarillado/química , Triazoles/análisis , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos , Eliminación de Residuos Líquidos/métodos , Aguas Residuales/química
4.
J Hazard Mater ; 244-245: 259-67, 2013 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-23257325

RESUMEN

The concentrations of nine emerging contaminants, including pharmaceutically active compounds (PhACs) (ibuprofen, IBF; naproxen, NPX; diclofenac, DCF; ketoprofen, KFN) and endocrine disrupting chemicals (triclosan, TCS; bisphenol, BPA; nonylphenol, NP; nonylphenol monoethoxylate, NP1EO; nonylphenol diethoxylate, NP2EO), were determined in wastewater and sludge samples of two wastewater treatment plants (WWTPs) in Greece. Average concentrations in raw and treated wastewater ranged from 0.39 (KFN) to 12.52 µg L(-1) (NP) and from 80%) during anaerobic digestion, whereas removal of EDCs was lower, ranging up to 55% for NP1EO.


Asunto(s)
Antiinflamatorios no Esteroideos/análisis , Disruptores Endocrinos/análisis , Eliminación de Residuos Líquidos , Aguas Residuales/análisis , Contaminantes Químicos del Agua/análisis , Anaerobiosis , Antiinflamatorios no Esteroideos/metabolismo , Disruptores Endocrinos/metabolismo , Aguas del Alcantarillado/análisis , Aguas del Alcantarillado/microbiología , Contaminantes Químicos del Agua/metabolismo
5.
Environ Sci Pollut Res Int ; 19(5): 1574-83, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22116734

RESUMEN

PURPOSE: The presence of four phenolic endocrine disrupting compounds (EDCs: nonylphenol [NP], NP monoethoxylate[NP1EO], bisphenol A [BPA], triclosan, [TCS]) and four nonsteroidal anti-inflammatory drugs (NSAIDs: ibuprofen[IBF], ketoprofen [KFN], naproxen [NPX], diclofenac [DCF]) in a Greek river receiving treated municipal wastewater was investigated in this study. METHODS: Samples were taken from four different points of the river and from the outlet of a sewage treatment plant (STP) during six sampling campaigns, and they were analyzed using gas chromatography-mass spectrometry. RESULTS: According to the results, EDCs were detected in almost all samples, whereas NSAIDs were detected mainly in wastewater and in the part of the river that receives wastewater from the STP. Among the target compounds, the highest mean concentrations in the river were detected for NP (1,345 ng L(-1)) and DCF (432 ng L(-1)). Calculation of daily loads of the target compounds showed that STP seems to be the major source of NSAIDs to the river, whereas other sources contribute significantly to the occurrence of EDCs. The environmental risk due to the presence of target compounds in river water was estimated, calculating risk quotients for different aquatic organisms (algae, daphnids, and fish). Results denoted the possible threat for the aquatic environment due to the presence of NP and TCS in the river.


Asunto(s)
Disruptores Endocrinos/análisis , Medición de Riesgo/métodos , Ríos/química , Contaminantes Químicos del Agua/análisis , Animales , Antiinflamatorios no Esteroideos/análisis , Organismos Acuáticos , Compuestos de Bencidrilo , Ecotoxicología/métodos , Monitoreo del Ambiente/métodos , Glicoles de Etileno/análisis , Peces , Cromatografía de Gases y Espectrometría de Masas , Grecia , Fenoles/análisis , Triclosán/análisis , Eliminación de Residuos Líquidos
6.
Anal Bioanal Chem ; 399(7): 2549-61, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21197532

RESUMEN

This article presents an analytical method based on solid-phase extraction (SPE) and gas chromatography coupled with mass spectrometry for the simultaneous determination of the most frequently used acidic pharmaceutical residues, ibuprofen, diclofenac, naproxen and ketoprofen (KFN), and phenolic endocrine disruptors, bisphenol (BPA), triclosan (TCS), nonylphenol, nonylphenol monoethoxylate and nonylphenol diethoxylate, in wastewater and sewage sludge samples. In the first phase of the study, each compound has been characterized individually and afterwards in mixture as a trimethylsilyl derivative in order to identify the characteristic ions (m/z ratio) constituting the mass spectrum and to choose the ions for quantification and confirmation. Subsequently, derivatization was evaluated by testing different variables such as the volume of the derivatization solvent bis(trimethylsilyl)trifluoroacetamide and the effect of each catalyst, pyridine and 1% trimethyl chlorosilane, in the derivatized solution. For the analysis of wastewater samples, two commercial SPE cartridges, C18 and Oasis HLB, were compared for their extraction efficiency of the target compounds. The key parameter of extraction procedure included the effect of pH (2.5, 5.3 and 7) of the loading solution. For solid samples, parameters such as the extracted biomass, the volume of the extraction organic solvent and the effect of matrix interferences in chromatographic analysis were evaluated. By using C18 cartridges as purification procedure and ultrasound sonication, satisfactory mean relative recoveries with BPA-d16 and meclofenamic acid as surrogates were obtained ranging from 91% to 117% for wastewater and 84% to 107% for sewage sludge samples. Nine-point calibration of the standard mixture was performed by linear regression analysis with a correlation coefficient >0.99 for all the tested compounds. Limits of detection for the developed methods were established between 0.3 (KFN) and 14.8 (BPA) ng L(-1), and 15.0 (TCS) and 32.9 (BPA) ng g(-1) for wastewater and sewage sludge, respectively. Application to real samples of the wastewater treatment plant in Athens, the capital of Greece, demonstrated the presence of all tested compounds in most of the samples.


Asunto(s)
Disruptores Endocrinos/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Preparaciones Farmacéuticas/análisis , Fenoles/análisis , Ácidos/análisis , Aguas del Alcantarillado/análisis , Extracción en Fase Sólida , Contaminantes Químicos del Agua/análisis
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