Direct and indirect photolysis of oxolinic acid in surface waters and its inhibition by antioxidant effects

作者：Luca Carena, Silvia Bertolotti, Viola Minutoli, Mohamed Sarakha, Annabel Fernandes, Ana M. Lopes, Fabrizio Sordello, Marco Minella, Davide Vione · 发表于：Water Research · 年份：2024 · DOI：10.1016/j.watres.2024.122880 · 被引用次数：7 · 研究领域：Pharmaceutical and Antibiotic Environmental Impacts、Water Quality Monitoring and Analysis、Advanced oxidation water treatment

• The photochemistry of the basic form of oxolinic acid (OxA) was investigated. • HO • and CO 3 •− radicals are highly reactive towards OxA. • OxA direct photolysis and reactions with CO 3 •− and 3 CDOM* are inhibited by phenol. • Phenol-induced inhibition of OxA photolysis is likely due to antioxidant effects. • The predicted photochemical lifetime of OxA in fresh- and seawater is of some days. Oxolinic acid is a quinolone antibiotic used in aquaculture to prevent and treat animal diseases. Because of its application and the large expansion of aquaculture in the latest decades, oxolinic acid enters environmental waters through the effluents of aquaculture facilities, posing concerns due to its potential adverse effects on aquatic ecosystems. It is thus important to study the fate of this antibiotic in water bodies. This work investigated the reactivity of the anionic form of oxolinic acid (OxA) by direct and indirect photolysis. The quantum yield of direct photolysis and the bimolecular rate constants of OxA reactions with reactive species photochemically produced in fresh- and seawater ( i.e. , HO • , CO 3 •− , triplet states of dissolved organic matter, 1 O 2 , and Br 2 •− ) were determined through steady-state irradiation experiments and laser flash photolysis measurements. Results showed that OxA photoreactivity is significant, in particular towards HO • and CO 3 •− radicals. However, the direct photolysis and reactions with CO 3 •− and the triplet states of dissolved or...