Recently developed GC/MS and LC/MS methods for determining NSAIDs in water samples

Pharmaceuticals have become major targets in environmental chemistry due to their presence in aquatic environments (following incomplete removal in wastewater treatment or point-source contaminations), threat to drinking water sources and concern about their possible effects to wildlife and humans. Recently several methods have been developed for the determination of drugs and their metabolites in the lower nanogram per litre range, most of them using solid-phase extraction (SPE) or solid-phase microextraction (SPME), derivatisation and finally gas chromatography mass spectrometry (GC-MS), gas chromatography tandem mass spectrometry (GC-MS/MS) and liquid chromatography electrospray tandem mass spectrometry (LC-ES/MS/MS). Due to the elevated polarity of non-steroidal anti-inflamatory drugs (NSAIDs), analytical techniques based on either liquid chromatography coupled to mass spectrometry (LC-MS) and gas chromatography coupled to mass spectrometry (GC-MS) after a previous derivatisation step are essential. The most advanced aspects of current GC-MS, GC-MS/MS and LC-MS/MS methodologies for NSAID analysis are presented.     

Development and application of methods using SPE,HPLC-DAD,LC-ESI-MS/MS and GFAAS for the determination of herbicides and metals in surface and drinking water

A preliminary study of the pollution in surface and drinking waters caused by herbicides and metals in the Municipal Water Supply System (CORSAN) in Rio Grande city, RS, Brazil, is reported. The occurrence of 5 herbicides and 9 metals was studied in surface and drinking water through the analysis of 2 sampling spots at CORSAN. The analytical determination was performed by solid-phase extraction (SPE), high performance liquid chromatography-photodiode array detection (HPLC-DAD) and liquid chromatography coupled to electrospray ionisation tandem mass spectrometry (LC-ESI-MS/MS) for herbicides, and graphite furnace atomic absorption spectrometry (GFAAS) for metals. The concentrations of herbicides in the surface water were very low; however, the herbicide clomazone was detected in more than 50% of the samples analysed in concentration exceeding 1.0?µg L^?1. The concentration of metals was below the Maximum Contaminant Level (MCL) set by the Brazilian regulation.     

液相色谱-串联质谱法测定污水处理厂水样中双酚A、四溴双酚A及烷基酚类化合物

近年来,双酚A、四溴双酚A及烷基酚类化合物由于其对水生生物的内分泌干扰作用受到越来越广泛的关注。污水处理厂是处理这类化合物的重要途径,研究目标物在其中的浓度分布对于探明此类物质在环境中的暴露水平具有重要意义,而建立相应的分析测定方法则是开展上述研究的基础。本研究建立了同时测定污水处理厂水样中双酚A、四溴双酚A及6种烷基酚类化合物的反相液相色谱-电喷雾串联质谱分析方法。结果发现,以ZORBAX Eclipse Plus C18色谱柱（150 mm×2.1 mm,3.5 μm）为分离柱,乙腈和0.02%（v/v）氨水溶液为梯度洗脱的流动相,电喷雾质谱负离子模式下目标化合物在11 min内分离;在1~100 μg/L范围内,双酚A、四溴双酚A及6种烷基酚类化合物的峰面积与质量浓度的线性关系良好（R²≥0.998）,方法定量限为2.0~20 ng/L;添加水平分别为0.2、2、20 μg/L时,目标化合物的平均回收率分别为64.3%~118.0%、65.9%~100.5%、70.3%~102.7%,相对标准偏差均小于7.1%。基于上述方法,对江苏省某工业园区污水处理厂水样中相关物质进行检测,出水中检出5种目标化合物,质量浓度范围为11.9~3015.3 ng/L。结果表明,该方法准确可靠、灵敏度高,适用于污水处理厂水样中相关烷基酚类化合物的检测。     

A fast and accurate isotope dilution GC‐IT‐MS/MS method for determination of eugenol in different tissues of fish: Application to a depletion study in mandarin fish

An accurate, rapid and effective method was established for determination of eugenol in plasma, muscle, skin, liver, kidney and gill of fish using gas chromatography–ion trap tandem mass spectrometry. Samples of muscle, skin, liver, kidney and gill were prepared using the modified QuEChERS (quick, easy, cheap, effective, rugged and safe) procedure, and a plasma sample was prepared by a liquid–liquid extraction procedure. Eugenol was monitored in <7 min using an electron‐ionization source in MS/MS mode and quantified by an internal standard of eugenol‐d₃. The limit of detection was 5.0 μg/kg, and the limit of quantification was 10.0 μg/kg. The calibration curve was linear in the range of 5–1000 μg/L (R² = 0.9996). Intra‐ and inter‐day precisions of eugenol expressed as relative standard deviation were within 9.74%, and the accuracy exhibited a relative error ranging from −2.20 to 8.89%. The developed method was successfully used to study the elimination regularity of eugenol in mandarin fish.     

Analysis of 32 priority substances from EU water framework directive in wastewaters,surface and drinking waters with a fast sample treatment methodology

A simple, fast, and sensitive method is proposed for the analysis of 32 priority substances (PS) from EU Water Framework Directive (WFD) and the first Watch List in effluents of wastewater treatment plants (EWW), surface waters (SW) and drinking waters (DW). Dispersive liquid-liquid microextraction (DLLME) and gas chromatography coupled to tandem mass spectrometry (GC-MS/MS) is used. For DLLME, a mixture of 1,1,2-trichloroethane as extraction solvent (75 µL) and acetonitrile as disperser solvent (3.2 mL) is proposed. The method was validated in EWW, SW and DW, showing satisfactory accuracy values ranging from 90% to 104%, good precision (relative standard deviation, RSD%, lower than 13%) and uncertainty values between 7% and 34%. Regarding sensitivity, method limits of quantification (MLOQs) of 4.8, 5.2 and 8.8 ng L^?1 for DW, SW and EWW, respectively, were obtained. The developed method was applied to analyze PS in water from effluents of waste water treatment plants (WWTPs), surface water of the Llobregat River and its main tributaries (Catalonia, NE Spain) and drinking water from a Drinking Water Treatment Plant (DWTP). Moreover, the efficiency of treatment plants (DWTP, WWTP) on the elimination of PS was evaluated. Only 3 PS (lindane, terbutryn and dicofol) were detected, being terbutryn the compound found at the highest levels (up to 493 ng L^?1 in EWW samples). Regarding environmental quality standard (WFD) for terbutryn in surface waters, only one sample, the Rubí stream (431 ng L^?1), showed levels of terbutryn higher than maximum allowable concentration (340 ng L^?1).