Cervantes-Díaz, Á., Nieto-Carmona, J.C., Sevilla-Morán, B. et al. Kinetic study, byproducts characterization and photodegradation pathway of profoxydim in a biocharBiochar is a carbon-rich material created from biomass decomposition in low-oxygen conditions. It has important applications in environmental remediation, soil improvement, agriculture, carbon sequestration, energy storage, and sustainable materials, promoting efficiency and reducing waste in various contexts while addressing climate change challenges. More water soil system. Sci Rep 14, 27117 (2024). https://doi.org/10.1038/s41598-024-78621-x

This study investigates how profoxydim, a herbicide used to control weeds in rice paddies, breaks down under sunlight in water and soil settings. The research focused on how biochar—an organic soil amendment—affects this photodegradation process. Using simulated sunlight, the scientists analyzed profoxydim’s half-life in both water and soil. In typical paddy water, the herbicide degraded in about 2.4 hours, and in paddy soil, it broke down even faster, with a half-life of 1.03 hours. When biochar was added, degradation slowed: profoxydim’s half-life extended to 3.1 hours in water and 3.07 hours in soil. This suggests biochar influences degradation by absorbing sunlight or interacting chemically, which may reduce profoxydim’s breakdown rate.

The study identified five degradation products (DPs) and proposed a new breakdown pathway for profoxydim, with transformations including photoisomerization and oxidative reactions. Two of these DPs were more stable than profoxydim, raising environmental concerns since persistent DPs can accumulate in paddy ecosystems. The findings underline the need for further research to fully understand how biochar impacts herbicide breakdown and potential risks associated with profoxydim residues. This research provides insights useful for developing sustainable rice farming practices that minimize environmental impact.