Photolysis of model emerging contaminants in ultra-pure water: Kinetics, by-products formation and degradation pathways

► Photolysis of five emerging contaminants (EC) was investigated. ► First-order rate constants and quantum yields were determined for each EC. ► The combined UV/H2O2 process provided a significant increase in the reaction rates. ► Intermediates were identified and the degradation pathways were proposed. ► Toxicity measurements showed an initial increase, followed by a decrease.