Effect of pH on the degradation of imidadoprid and fipronil in paddy water

This study investigated the degradation of imidadoprid and fipronil in paddy water at pH 7 and pH 10. Both imidadoprid and fipronil degraded faster at pH 10, and fipronil degraded faster than imidacloprid at pH 10. The half-life estimates of imidacloprid were 182 and 44.7 days at pH 7 and pH 10, respectively, and those values of fipronil were 87.9 and 13.2 days, respectively. Fipronil sulfone was found in the degradation process of fipronil. (C) Pesticide Science Society of Japan