Photochemical Formation of Long-Lived Oxidative Organic Radicals from Algal-Derived Dissolved Organic Matter under Solar Irradiation

for UV), owing to the stronger light absorption in the visible range. The formation of LLRSs was classified into dissolved oxygen (DO)-inhibited and DO-promoted pathways, with DO-inhibited processes accounting for 98% and 87% of the total LLRSs formation in SRDOM and ADOM, respectively. The degradation of 27 emerging organic contaminants demonstrated greater LLRSs involvement in ADOM, especially under visible light. These results underscore the key role of LLRSs in contaminant attenuation in bloom-impacted waters and highlight the importance of visible-light-driven photochemistry in enhancing the self-purification potential of ADOM-affected waters.