Breakpoint Chlorination Chemistry in a Chlorine-Cyanurate System and Trade-Offs between Nitrosamine Formation and Micropollutant Removals.

ABSTRACT: Breakpoint chlorination occurs in swimming pools and generates •OH and nitrosating agents. While •OH facilitates micropollutant removal, nitrosating agents promote nitrosamine formation. Cyanuric acid, a common chlorine stabilizer, reacts reversibly with free chlorine to form chlorinated cyanurates, effectively "locking" free chlorine and altering breakpoint chemistry. Accurate estimation of free chlorine is essential for evaluating these impacts and depends on the hydrolytic dissociation constants of chlorinated cyanurates, yet reported values vary widely. This study re-evaluates these constants and examines how cyanuric acid influences breakpoint reactions, focusing on the trade-off between •OH-driven micropollutant degradation and nitrosamine formation. Using phenolic probes, we show th

SUBMITTER: Chuang YH 

PROVIDER: S-EPMC12676743 | biostudies-literature | 2025 Dec

REPOSITORIES: biostudies-literature