Simultaneous Derivatization and Trapping of Volatile Products from Aqueous Photolysis of Thiamethoxam Insecticide

An aqueous photolysis study was conducted with radiolabeled thiamethoxam, 4H-1,3,5-oxadiazin-2-imine, 3-[(2-chloro-5-thiazolyl)methyl]tetrahydro-5-methyl-N-nitro, to establish the relevance of aqueous photolysis as a transformation process for 14 C-[thiazolyl]-thiamethoxam. 14 C-[thiazolyl]-thiamethoxam was applied to sterile sodium acetate pH 5 buffer solution at a dose rate of approximately 10 ppm. The resulting samples were incubated for up to 30 days at 25 °C under irradiated and nonirradiated conditions. The irradiated samples were exposed to a 12-hour-on and 12-hour-off light cycle. Volatile fractions accounted for up to an average of 56.76% of the total dose for the irradiated incubations and