title: Photo-Fenton-like treatment of BPA: effect of UV light source and water matrix on toxicity and transformation products.
abstract: UV-A (near-UV), UV-C (short-UV) and visible-light assisted Fenton-like treatment of Bisphenol A (BPA) was investigated in pure water and raw freshwater samples spiked with BPA. Treatment performances were evaluated in terms of BPA degradation, dissolved organic carbon (DOC) removal and H2O2 consumption rates. Complete BPA degradation accompanied with significant DOC removal was achieved for all studied processes. Increasing the initial solution pH only exhibited a negative effect on treatment efficiencies when bicarbonate alkalinity was used for pH adjustment, whereas the raw freshwater matrix and irradiation type also influenced oxidation rates appreciably. Acute toxicity analysis employing Vibrio fischeri revealed that the inhibitory effect of BPA decreased significantly during the course of Photo-Fenton-like treatment. Several transformation products could be identified via HPLC and GC-MS analyses including hydroxylated phenolic compounds (hydroquinone; 2-methoxy, 1-4-benzenediol; 4-isopropenylphenol; 4'-hydroxy-acetophenone; 1-(4-cyclohexylphenyl) ethanone; 4-isopropylenecatechol; 4-4'-dihydroxybenzophenone; 4-ethyl,1,3-benzenediol), as well as the ring opening products hexanoic acid methyl ester, fumaric, succinic and oxalic acids. A reaction pathway featuring hydroxylation, dimerization and ring opening steps is proposed.
authors.affiliation: Berlin University of Technology, Department of Water Quality and Control, Strasse des 17. Juni 135, 10623 Berlin, Germany.
authors.forename: Merle
authors.initials: M
authors.lastname: Molkenthin
authors.forename: Tugba
authors.initials: T
authors.lastname: Olmez-Hanci
authors.forename: Martin R
authors.initials: MR
authors.lastname: Jekel
authors.forename: Idil
authors.initials: I
authors.lastname: Arslan-Alaton
mesh_terms: D048908:Aliivibrio fischeri / Q000187:drug effects; D001559:Benzhydryl Compounds / Q000737:chemistry* / Q000633:toxicity*; D002851:Chromatography, High Pressure Liquid; D005618:Fresh Water / Q000737:chemistry; D008401:Gas Chromatography-Mass Spectrometry; D006861:Hydrogen Peroxide / Q000737:chemistry; D010636:Phenols / Q000032:analysis / Q000737:chemistry* / Q000633:toxicity*; D010777:Photochemistry / Q000379:methods; D018675:Toxicity Tests / Q000379:methods; D014466:Ultraviolet Rays; D014867:Water; D000098826:Bisphenol A Compounds
chemical_list: D001559:Benzhydryl Compounds; D006861:Hydrogen Peroxide; D010636:Phenols; D014867:Water; C006780:bisphenol A; D000098826:Bisphenol A Compounds
keywords: Acute toxicity; Bisphenol A; Irradiation type; Photo-Fenton-like treatment; Reaction pathway; Transformation products