A rapid prediction method for estimating ozone reaction with anthropogenic organic compounds in the pollutant release and transfer register (PRTR) system.

Measuring the absolute rate constants for ozone (O3) reactivity with organic compounds in water is challenging and time-consuming due to O3 instability and complex procedures. To simplify this process, this study introduces a single-point method that determines the apparent second-order rate constants ( [Formula: see text] ) using residual O3 concentrations from a single sampling time, providing a simple and time-efficient approach for handling large databases comprising many compounds. The method was validated against literature data, and it was found to be sufficient for practical applications, with an upper limit of [Formula: see text] = 600 M-1s-1 representing highly O3 reactive-compounds. The single-point method was applied to 69 target compounds containing electron-rich moieties (ERMs) listed in the Japanese Pollutant Release and Transfer Register (PRTR) system. The results agreed well with those of previous studies, confirming the ability of the method to distinguish between fast- and slow-reacting compounds. Moreover, new data were obtained for compounds lacking literature data, helping to fill key data gaps. Based on these findings and previous research, a flowchart was developed to rapidly screen the treatability of organic compounds by ozonation. The flowchart successfully predicted the reactivity of > 98% of the target PRTR compounds, as confirmed by both internal and external validation.