Microwave assisted extraction followed by gas chromatography with tandem mass spectrometry for the determination of triclosan and two related chlorophenols in sludge and sediments.
A procedure for the determination of 2-(2,4-dichlorophenoxy)-5-chlorophenol (Triclosan) and two possible transformation compounds, 2,4-dichlorophenol (2,4-DCP) and 2,4,6-trichlorophenol (2,4,6-TCP), in sludge from sewage treatment plants (STP) and sediments is presented. Extraction was performed using an acetone:methanol (1:1) mixture under the action of a microwave field. The centrifuged supernatant was diluted with a NaOH aqueous solution and twice extracted with n-hexane for removing neutral and basic interferences. The aqueous layer was acidified and processed as a waste water sample. After concentration analytes were silylated and determined by gas chromatography with tandem mass spectrometry (GC-MS/MS). Influence of experimental conditions on the yield of the extraction process and on the efficiency of the further clean-up step was thoroughly evaluated. Performance of MS/MS detection in comparison to single MS is described. Under final working conditions quantification limits between 0.4 and 0.8 ng/g and recoveries from 78% to 106% were obtained. The method was applied to the analysis of several sludge and sediment samples. Only low levels of TCS were detected in some of the sediments; however, all three compounds were found in sludge samples at concentrations ranging from 7 to 316 ng/g, in the case of chlorophenols, and from 420 to 5400 ng/g, for Triclosan.
Morales
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S
Departamento de Química Analítica, Nutrición y Bromatología, Instituto de Investigaciń y Análisis Alimentario, Universidad de Santiago de Compostela, Santiago de Compostela 15782, Spain.
Canosa
P
P
Rodríguez
I
I
Rubí
E
E
Cela
R
R
D005591:Chemical Fractionation; D002733:Chlorophenols / Q000032:analysis*; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D019015:Geologic Sediments / Q000737:chemistry*; D008872:Microwaves; D015203:Reproducibility of Results; D012722:Sewage / Q000737:chemistry*; D014260:Triclosan / Q000032:analysis*
D002733:Chlorophenols; D012722:Sewage; D014260:Triclosan; C024564:2,4,6-trichlorophenol; C004762:2,4-dichlorophenol