Dissipation of fipronil in water under laboratory conditions.

Fipronil belongs to phenyl-pyrazole class of chemical compounds. Its dissipation in water has been studied for 90 days under laboratory conditions at two dose 0.028 (T1) and 0.056 (T2) μg mL−1. Residues were extracted with 15% dichloromethane in hexane by liquid-liquid partitioning and were estimated by GC-ECD system equipped with capillary column. Fipronil was found to persist up to 30 days after application and 100% dissipation was observed after 60 days of application. Dissipation followed a biphasic first order kinetics with half-life values of 19.13 and 20.63 days in water at (T1) and (T2) treatments, respectively.