Structure confirmation, reactivity, bacterial mutagenicity and quantification of 2,2,4-tribromo-5-hydroxycyclopent-4-ene-1,3-dione in drinking water

• DOI: 10.1038/s42004-024-01356-3
• Publication Date: 2024-11-14T14:48:14Z
• Authors: Davide Ciccarelli; Ben M. J. Lancaster; D. Christopher Br...; Matteo Calvaresi; Miroslav Mišík; Siegfried Knasmüller; Edoardo Jun Mattioli; Francesco Zerbetto; Andrew J. P. White; Tim Marczylo; Timothy W. Gant; Leon P. Barron
• Keywords: Ene reaction

Abstract The presence of two new disinfectant by-product (DBP) groups in the UK was recently shown using non-target analysis, halogenated-hydroxycyclopentenediones and halogenated-methanesulfonic acids. In this work, we confirmed structure 2,2,4-tribromo-5-hydroxycyclopent-4-ene-1,3-dione (TBHCD), quantified it together with dibromomethanesulfonic acid at 122 ± 34 326 157 ng L −1 on average London’s drinking water, respectively ( n = 21). We found TBHCD to be photolabile unstable tap water alkaline pH. Furthermore, spectral computational data for three other indicated they could act as a source radicals body. Importantly, calculated have 14.5 kcal mol lower C-Br bond dissociation enthalpy than N-Br N -bromosuccinimide, common radical substitution reagent used organic synthesis. mutagenic Salmonella/microsome assays strains TA98, TA100 TA102. This work reveals unique features, activity toxicity trihalogenated hydroxycyclopent-4-ene-1,3-diones, prompting need more comprehensively assess their risks.