title: Further research on the photo-SPME of triclosan.
abstract: In this study the photoinduced degradation of triclosan has been investigated by photo-solid-phase microextraction (photo-SPME). In photo-SPME, photodegradation is carried out on the SPME fibre containing the target compound. Triclosan was extracted from aqueous solutions by use of polydimethylsiloxane SPME fibres and these were subsequently exposed to UV irradiation (power 8 W, wavelength 254 nm) for different times (from 2 to 60 min). The photodegradation kinetics of triclosan were investigated, the photoproducts generated were tentatively identified, and the photochemical behaviour of these products was studied by use of this on-fibre approach followed by gas chromatographic-mass spectrometric analysis. Eight photoproducts were tentatively identified, including chlorinated phenols, chlorohydroxydiphenyl ethers, 2,8-dichlorodibenzo-p-dioxin, and a possible dichlorodibenzodioxin isomer or dichlorohydroxydibenzofuran. The main photodegradation mechanisms were postulated and photodegradation pathways proposed. The effect of pH on triclosan degradation and on triclosan-to-dioxin conversion was also investigated. Triclosan degradation occurred, and generation of 2,8-dichlorodibenzo-p-dioxin was confirmed, throughout the pH range studied (from 3 to 9).
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.
authors.forename: Lucia
authors.initials: L
authors.lastname: Sánchez-Prado
authors.forename: Maria
authors.initials: M
authors.lastname: Llompart
authors.forename: Marta
authors.initials: M
authors.lastname: Lores
authors.forename: Maria
authors.initials: M
authors.lastname: Fernández-Alvarez
authors.forename: Carmen
authors.initials: C
authors.lastname: García-Jares
authors.forename: Rafael
authors.initials: R
authors.lastname: Cela
mesh_terms: D000891:Anti-Infective Agents, Local / Q000032:analysis*; D001557:Benzenesulfonates / Q000032:analysis*; D002733:Chlorophenols / Q000737:chemistry; D002849:Chromatography, Gas / Q000379:methods*; D002852:Chromatography, Ion Exchange / Q000379:methods; D004147:Dioxins / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008027:Light; D013058:Mass Spectrometry / Q000379:methods*; D008956:Models, Chemical; D010777:Photochemistry / Q000379:methods; D013997:Time Factors; D014260:Triclosan / Q000032:analysis* / Q000737:chemistry; D014466:Ultraviolet Rays
chemical_list: D000891:Anti-Infective Agents, Local; D001557:Benzenesulfonates; D002733:Chlorophenols; D004147:Dioxins; C056082:4-sulfophenylmethallyl ether; D014260:Triclosan