Identification of Transformation Products of Organic UV Filters by Photooxidation and Their Differential Estrogenicity Assessment

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review

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Detail(s)

Original languageEnglish
Pages (from-to)17110−17122
Journal / PublicationEnvironmental Science & Technology
Volume57
Issue number44
Online published18 Oct 2023
Publication statusPublished - 7 Nov 2023

Abstract

Organic ultraviolet filters (OUVFs) are extensively released into aquatic environments, where they undergo complex phototransformation. However, there is little knowledge regarding their transformation products (TPs) and associated endocrine disruption potentials. In the present study, we characterized the chemical and toxicological profiles of TPs for two common OUVFs, oxybenzone (BP3) and ethylhexyl methoxycinnamate (EHMC), by photooxidation under environmentally relevant conditions. It is hypothesized that TPs of the tested OUVFs will show varied estrogenicity at different reaction times. High-resolution liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) identified 17 TPs of 7 m/z for BP-3 and 13 TPs of 8 m/z for EHMC at confidence levels ≤2. Five novel TPs of 2 m/z were reported for the first time with structure-diagnostic MS/MS spectra. Estrogenicity assessment using the MCF-7-luc cell line showed discrepant estrogenic activities exhibited by OUVF-TPs over time. Specifically, BP3-TPs exhibited significantly greater estrogenicity than the parent at several reaction times, whereas EHMC-TPs displayed fluctuating estrogenicity with a declining trend. Correlation analysis coupled with molecular docking simulations further suggested several TPs of BP3 as potential endocrine disruptive compounds. These findings underscore the necessity of considering mixtures during chemical testing and risk assessment and highlight the potentially greater risks associated with post-transformation cocktails. © 2023 American Chemical Society.

Research Area(s)

  • organic UV filter, transformation product (TP), oxybenzone (BP3), ethylhexyl methoxycinnamate (EHMC), estrogenicity

Citation Format(s)

Identification of Transformation Products of Organic UV Filters by Photooxidation and Their Differential Estrogenicity Assessment. / Lu, Yichun; Chow, Man Kwan; Sun, Jiaji et al.
In: Environmental Science & Technology, Vol. 57, No. 44, 07.11.2023, p. 17110−17122.

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review