Identificación y cuantificación de contaminantes emergentes en aguas residuales por microextracción en fase sólida-cromatografía de gases-espectrometría de masas (MEFS-CG-EM)

Abstract

A methodology by SPME-GC-MS was developed and optimized for the simultaneous determination of pharmaceutical and personal care products (PPCP's) in wastewater: ibuprofen, naproxen, chlorofen, triclosan and bisphenol A. The extraction of analytes was performed by SPME using a fiber of PEG (Polietylenglycol), stirring of 1,200 rpm, 30 min extraction time at ambient temperature, 50% NaCl, pH=3 and derivatization on fiber with MTBSTFA (N-methyl-N-tert-butyl-dimethylsilil-trifluoroacetamide). The identification of the analytes was done by comparison of the retention times and the mass spectrum of standards. The quantification was done by selective ion monitoring (SIM) mode. The developed method shown acceptable linearity in the range of 1.0-118.90 pg/mL for ibuprofen, 48.0-1488 pg/mL for naproxen, 4.40-140.8 pg/mL for triclosan, 1.0-58.32 pg/mL for chlorofen, and 1.0-59.16 pg/mL for bisphenol A, all of them with correlation coefficients > 0.99. Several water samples from influents and effluents were analyzed from three wastewater treatment plants in the south of the Mexico City: “University”, “Coyoacan” and “Cerro de la Estrella” all of them belong to the water system of Mexico City. It was shown in this work that SPME is a sample preparation technique that is simple, reproducible, sensitive and fast because it reduces the steps by extracting and simultaneously concentrating the analytes without the use of organic solvents.