title: Degradation Products of Benzophenone-3 in Chlorinated Seawater Swimming Pools.
abstract: Oxybenzone (2-hydroxy-4-methoxyphenone, benzophenone-3) is one of the UV filters commonly found in sunscreens. Its presence in swimming pools and its reactivity with chlorine has already been demonstrated but never in seawater swimming pools. In these pools, chlorine added for disinfection results in the formation of bromine, due to the high levels of bromide in seawater, and leads to the formation of brominated disinfection byproducts, known to be more toxic than chlorinated ones. Therefore, it seems important to determine the transformation products of oxybenzone in chlorinated seawater swimming pools; especially that users of seawater swimming pools may apply sunscreens and other personal-care products containing oxybenzone before going to pools. This leads to the introduction of oxybenzone to pools, where it reacts with bromine. For this purpose, the reactivity of oxybenzone has been examined as a function of chlorine dose and temperature in artificial seawater to assess its potential to produce trihalomethanes and to determine the byproducts generated following chlorination. Increasing doses of chlorine and increasing temperatures enhanced the formation of bromoform. Experiments carried out with excess doses of chlorine resulted in the degradation of oxybenzone and allowed the determination of the degradation mechanisms leading to the formation of bromoform. In total, ten transformation products were identified, based on which the transformation pathway was proposed.
authors.affiliation: Aix Marseille Université, CNRS, LCE FRE 3416, 13331 Marseille, France.
authors.forename: Tarek
authors.initials: T
authors.lastname: Manasfi
authors.affiliation: Aix Marseille Université, CNRS, LCE FRE 3416, 13331 Marseille, France.
authors.forename: Veronika
authors.initials: V
authors.lastname: Storck
authors.affiliation: Aix Marseille Université, CNRS, LCE FRE 3416, 13331 Marseille, France.
authors.forename: Sylvain
authors.initials: S
authors.lastname: Ravier
authors.affiliation: Aix Marseille Université, CNRS, LCE FRE 3416, 13331 Marseille, France.
authors.forename: Carine
authors.initials: C
authors.lastname: Demelas
authors.affiliation: Aix Marseille Université, CNRS, LCE FRE 3416, 13331 Marseille, France.
authors.forename: Bruno
authors.initials: B
authors.lastname: Coulomb
authors.affiliation: Aix Marseille Université, CNRS, LCE FRE 3416, 13331 Marseille, France.
authors.forename: Jean-Luc
authors.initials: JL
authors.lastname: Boudenne
mesh_terms: D001577:Benzophenones / Q000737:chemistry*; D002713:Chlorine / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid; D004203:Disinfection; D008401:Gas Chromatography-Mass Spectrometry; D054879:Halogenation; D007700:Kinetics; D012623:Seawater / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization; D013551:Swimming Pools; D022882:Trihalomethanes / Q000737:chemistry
chemical_list: D001577:Benzophenones; D022882:Trihalomethanes; D002713:Chlorine; C005290:oxybenzone; C015044:bromoform