title: Photochemical transformation of sunscreen agent benzophenone-3 and its metabolite in surface freshwater and seawater.
abstract: The occurrence of sunscreen agents and their metabolites in surface waters gives rise to public concerns. However, little is known about the environmental fate of these pollutants at present, especially for their metabolites. In this study, we investigated the photochemical of sunscreen agents and their metabolites in natural waters, adopting benzophenone-3 (BP-3) and its human metabolite 4-hydroxybenzophenone (4-OH-BP3) as examples. Results show that only anionic forms of both BP-3 and 4-OH-BP3 can undergo direct photodegradation. The photolytic rates of both compounds in natural waters are faster as compared to those in pure water. Radical scavenging experiments revealed that triplet-excited dissolved organic matter ((3)DOM(∗)) was responsible for the indirect photodegradation of BP-3 and 4-OH-BP3 in seawater, whereas in freshwater, the indirect photodegradation of these two compounds was attributed to (3)DOM(∗) and ·OH. (1)O2 plays a negligible role in their photodegradation because of the weak (1)O2 reactivity. Furthermore, we probed the contribution of ·OH and (3)DOM(∗) to the photodegradation of both compounds in freshwater, and the results revealed that ·OH accounted for 56% and 59% of the observed photodegradation for BP-3 and 4-OH-BP3, respectively, whereas (3)DOM(∗) accounted for 43% and 12% of the observed photodegradation for BP-3 and 4-OH-BP3, respectively. These results are helpful in assessing the ecological risk of BP-3 and its metabolite in the aquatic environment.
authors.affiliation: Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China.
authors.forename: Yingjie
authors.initials: Y
authors.lastname: Li
authors.affiliation: Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China. Electronic address: xlqiao@dlut.edu.cn.
authors.forename: Xianliang
authors.initials: X
authors.lastname: Qiao
authors.affiliation: Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China.
authors.forename: Chengzhi
authors.initials: C
authors.lastname: Zhou
authors.affiliation: Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China.
authors.forename: Ya-Nan
authors.initials: YN
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China.
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Fu
authors.affiliation: Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China.
authors.forename: Jingwen
authors.initials: J
authors.lastname: Chen
mesh_terms: D001577:Benzophenones / Q000737:chemistry*; D005618:Fresh Water / Q000737:chemistry; D010782:Photolysis; D012623:Seawater / Q000737:chemistry; D013473:Sunscreening Agents / Q000737:chemistry*; D014867:Water / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D001577:Benzophenones; D013473:Sunscreening Agents; D014874:Water Pollutants, Chemical; C024292:4-hydroxybenzophenone; D014867:Water; C005290:oxybenzone
keywords: Benzophenone-3; Hydroxyl radical; Metabolites; Photodegradation; Triplet-excited dissolved organic matter