Three different UV-LED wavelengths (265, 310, and 365 nm) were used in the UV-LED/chlorine reaction to investigate the degradation mechanism of iopromide (IPM) at different wavelengths, a representative iodinated contrast media compound. The degradation rate (k′_IPM) increased from pH 6–8 at 265 nm, but, decreased as the pH increased up to 9 at 310 nm and 365 nm. Radical scavenging experiments showed that reactive chlorine species (RCS) are the dominant radical species at all wavelengths, but a higher contribution of OH• was observed at lower pH and longer wavelengths. The contribution of RCS decreased but the contribution of OH• increased as the wavelength increased. Among RCS, the largest contribution was found to be ClO•. Total nine transformation products (TPs) were identified by LC-QTOF-MS during the UV-LED/chlorine reaction at 265 nm. Based on the identified TPs and their time profiles, we proposed a degradation pathway of IPM during UV-LED/chlorine reaction. The Microtox test using V. fischeri showed that no significant increase in toxicity was observed at all wavelengths. The synergistic effect of UV-LED and chlorine was greater at a higher wavelength by the electrical efficiency per order (EEO) calculation.

在 UV-LED/氯反应中使用三种不同的 UV-LED 波长（265、310 和 365 nm）来研究碘普罗胺 (IPM) 在不同波长下的降解机制，这是一种代表性的碘化造影剂化合物。降解率 (k' _IPM) 在 265 nm 处从 pH 6–8 增加，但随着 pH 在 310 nm 和 365 nm 处增加到 9 而降低。自由基清除实验表明，活性氯物质（RCS）是所有波长的主要自由基物质，但在较低的 pH 值和较长的波长下观察到 OH• 的贡献较高。随着波长的增加，RCS 的贡献减少，但OH• 的贡献增加。在RCS 中，最大的贡献被发现是ClO•。在 265 nm 的 UV-LED/氯反应期间，LC-QTOF-MS 共鉴定了九种转化产物 (TP)。基于已识别的 TP 及其时间分布，我们提出了 IPM 在 UV-LED/氯反应过程中的降解途径。使用V. fischeri的 Microtox 测试表明在所有波长下都没有观察到毒性显着增加。通过每级电效率 (EEO) 计算，UV-LED 和氯的协同效应在更高波长处更大。