title: Monitoring trihalomethanes in chlorinated waters using a dispersive liquid-liquid microextraction method with a non-chlorinated organic solvent and gas chromatography-mass spectrometry.
abstract: The environmental monitoring of trihalomethanes (THMs) has been performed by setting up a dispersive liquid-liquid microextraction method in combination with gas chromatography (GC)-mass spectrometry (MS). The optimized method only requires ∼26 µL of decanol as extractant solvent, dissolved in ∼1 mL of acetone (dispersive solvent) for 5 mL of the environmental water containing THMs. The mixture is then subjected to vortex for 1 min and then centrifuged for 2 min at 3500 rpm. The microdroplet containing the extracted THMs is then sampled with a micro-syringe, and injected (1 µL) in the GC-MS. The method is characterized for being fast (3 min for the entire sample preparation step) and environmentally friendly (low amounts of solvents required, being all non-chlorinated), and also for getting average relative recoveries of 90.2-106% in tap waters; relative standard deviation values always lower than 11%; average enrichment factors of 48-49; and detection limits down to 0.7 µg·L-1. Several waters: tap waters, pool waters, and wastewaters were successfully analyzed with the method proposed. Furthermore, the method was used to monitor the formation of THMs in wastewaters when different chlorination parameters, namely temperature and pH, were varied.
authors.affiliation: a Departamento de Química, Unidad Departamental de Química Analítica , Universidad de La Laguna (ULL) , La Laguna , Tenerife , Spain.
authors.forename: Idaira
authors.initials: I
authors.lastname: Pacheco-Fernández
authors.affiliation: a Departamento de Química, Unidad Departamental de Química Analítica , Universidad de La Laguna (ULL) , La Laguna , Tenerife , Spain.
authors.forename: Ariadna
authors.initials: A
authors.lastname: Herrera-Fuentes
authors.affiliation: a Departamento de Química, Unidad Departamental de Química Analítica , Universidad de La Laguna (ULL) , La Laguna , Tenerife , Spain.
authors.forename: Bárbara
authors.initials: B
authors.lastname: Delgado
authors.affiliation: a Departamento de Química, Unidad Departamental de Química Analítica , Universidad de La Laguna (ULL) , La Laguna , Tenerife , Spain.
authors.forename: Verónica
authors.initials: V
authors.lastname: Pino
authors.affiliation: a Departamento de Química, Unidad Departamental de Química Analítica , Universidad de La Laguna (ULL) , La Laguna , Tenerife , Spain.
authors.forename: Juan H
authors.initials: JH
authors.lastname: Ayala
authors.affiliation: a Departamento de Química, Unidad Departamental de Química Analítica , Universidad de La Laguna (ULL) , La Laguna , Tenerife , Spain.
authors.forename: Ana M
authors.initials: AM
authors.lastname: Afonso
mesh_terms: D004203:Disinfection; D004784:Environmental Monitoring / Q000379:methods*; D008401:Gas Chromatography-Mass Spectrometry; D054879:Halogenation; D059627:Liquid Phase Microextraction; D012997:Solvents / Q000032:analysis; D022882:Trihalomethanes / Q000032:analysis*; D014874:Water Pollutants, Chemical / Q000032:analysis*; D018508:Water Purification
chemical_list: D012997:Solvents; D022882:Trihalomethanes; D014874:Water Pollutants, Chemical
keywords: Trihalomethanes; disinfection byproducts; dispersive liquid–liquid microextraction; drinking waters; gas chromatography