title: Confirmation of the formation of dichlorodibenzo-p-dioxin in the photodegradation of triclosan by photo-SPME.
abstract: Photodegradation is a possible way to eliminate organic pollutants from the environment but, at the same time, can be a source of toxic byproducts. The photochemical conversion of triclosan, a common pollutant in continental waters, into dichlorodibenzo-p-dioxin (DCDD) has been confirmed in our preliminary experiments employing photo-SPME (photo-solid-phase microextraction) using 18-W UV irradiation at 254-nm wavelength. Under these conditions, triclosan is rapidly photodegraded (70% of triclosan was degraded in 2 min); the most important novel aspect of this work is the conversion of triclosan to DCDD directly on the polydimethylsiloxane coating of the SPME fiber. Moreover, this conversion is also confirmed in non-buffered aqueous photodegradation experiments using SPME as the extraction technique. In all the experiments of this study, analysis was carried out by gas chromatography-electronic impact mass spectrometry (GC-EI/MS).
authors.affiliation: Departamento de Quimica Analitica, Nutricion y Bromatologia, Facultad de Quimica' Instituto de Investigacion y Analisis Alimentario, Universidad de Santiago de Compostela, Avda. das Ciencias s/n, 15782, Santiago de Compostela, Spain. qnmlores@usc.es
authors.forename: Marta
authors.initials: M
authors.lastname: Lores
authors.forename: Maria
authors.initials: M
authors.lastname: Llompart
authors.forename: Lucia
authors.initials: L
authors.lastname: Sanchez-Prado
authors.forename: Carmen
authors.initials: C
authors.lastname: Garcia-Jares
authors.forename: Rafael
authors.initials: R
authors.lastname: Cela
mesh_terms: D004147:Dioxins / Q000302:isolation & purification* / Q000633:toxicity; D004785:Environmental Pollutants / Q000302:isolation & purification* / Q000633:toxicity; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D010777:Photochemistry; D012680:Sensitivity and Specificity; D014260:Triclosan / Q000737:chemistry / Q000378:metabolism*
chemical_list: D004147:Dioxins; D004785:Environmental Pollutants; D014260:Triclosan; C503656:dichlorodibenzo-p-dioxin