RESUMEN
The aim of this study was to evaluate the performance of two forms of basic granular activated carbon (GAC), mineral (pH = 10.5) and vegetal (pH = 9), for the removal of three pharmaceuticals, as sulphamethoxazole (SMX), diclofenac (DCF) and 17ß-estradiol (E2), from two different matrices: fortified distilled (2.4-3.0â mgâ L(-1) and pH from 5.5 to 6.5) and natural (â¼1.0â mgâ L(-1) and pH from 7.1 to 7.2) water in a bench scale. The Rapid Small-Scale Column Test used to assess the ability of mineral and vegetal GAC on removal of such pharmaceuticals led to removal capacities varying from 14.9 to 23.5â mgâ g(-1) for E2, from 23.7 to 24.2â mgâ g(-1) for DCF and from 20.5 to 20.6â mgâ g(-1) for SMX. Removal efficiencies of 71%, 88% and 74% for DCF, SMX and E2, respectively, were obtained at breakthrough point when using mineral GAC, whereas for the vegetal GAC the figures were 76%, 77% and 65%, respectively. The carbon usage rate at the breakthrough point varied from 11.9 to 14.5â Lâ g(-1) for mineral GAC and from 8.8 to 14.8â Lâ g(-1) for vegetal GAC. Mineral CAG also exhibited the best performance when treating fortified natural water, since nearly complete removal was observed for all contaminants in the column operated for 22â h at a carbon usage rate of 2.9â Lâ g(-1).
Asunto(s)
Carbón Orgánico/química , Diclofenaco/aislamiento & purificación , Disruptores Endocrinos/aislamiento & purificación , Estradiol/aislamiento & purificación , Sulfametoxazol/aislamiento & purificación , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua/métodos , Adsorción , Diseño de Equipo , Agua/análisis , Purificación del Agua/instrumentación , Abastecimiento de AguaRESUMEN
Endocrine Disrupter Compounds (EDCs) are responsible for alterations in the endocrine system functions. Aquatic organisms are able to accumulate EDCs residues, being the major source of contamination for top predators and human consumers. This study aimed to develop and validate a method for the determination of 40 EDCs in fish fillet using modified QuEChERS and Gas Chromatography coupled with Mass Spectrometry in tandem (GC-MS/MS). A factorial design was used to optimize the extraction procedure. Method validation presented recoveries from 70.1% to 120.0% with RSD<20% and method limit of detection ranged from 0.3 to 7.5 µg kg(-1), showing good accuracy and precision. This method was successfully applied to the analysis of fish fillet from different species and residues of bisphenol A, chlorpyrifos and bifenthrin were detected. The proposed method proved to be effective for the determination of EDCs in fish fillet at very low concentration levels.
Asunto(s)
Compuestos de Bencidrilo/aislamiento & purificación , Cloropirifos/aislamiento & purificación , Disruptores Endocrinos/aislamiento & purificación , Productos Pesqueros/análisis , Fenoles/aislamiento & purificación , Piretrinas/aislamiento & purificación , Espectrometría de Masas en Tándem/métodos , Contaminantes Químicos del Agua/aislamiento & purificación , Animales , Análisis Factorial , Peces , Cromatografía de Gases y Espectrometría de Masas , Humanos , Límite de DetecciónRESUMEN
The synthetic estrogen ethinylestradiol (EE2) is an active component of oral contraceptives (OCs), considered as an endocrine disrupting compound (EDC). It is excreted from humans and released via sewage treatment plant effluents into aquatic environments. EDCs are any environmental pollutant chemical that, once incorporated into an organism, affects the hormonal balance of various species including humans. Its presence in the environment is becoming of great importance in water quality. This paper describes the development of an accurate, sensitive and selective method for capture, preconcentration and determination of EE2 present in water samples using: magnetic particles (MPs) as bioaffinity support for the capture and preconcentration of EE2 and a glassy carbon electrode modified with multi-walled carbon nanotubes (MWCNTs/GCE) as detection system. The capture procedure was based on the principle of immunoaffinity, the EE2 being extracted from the sample using the anti-EE2 antibodies (anti-EE2 Ab) which were previously immobilized on MPs. Subsequently the analyte desorption was done employing a sulfuric acid solution and the determination of the EE2 in the pre-concentrated solution was carried out by square wave voltammetry (SWV). This method can be used to determine EE2 in the range of 0.035-70 ng L(-1) with a detection limit (LOD) of 0.01 ng L(-1) and R.S.D.<4.20%. The proposed method has been successfully applied to the determination of EE2 in water samples and it has promising analytical applications for the direct determination of EE2 at trace levels.