Dissipation Kinetics and Safety Evaluation of Mixed Formulation of Emamectin Benzoate 1.5% + Fipronil 3.5% w/v EC on Chilli

Dissipation kinetics of a mixed formulation (emamectin benzoate 1.5 per cent and fipronil 3.5 per cent w/v EC) applied @ 750 and 1500 mL ha⁻¹ in a multi-location field study on chilli during 2011–2013 is reported. Residues of both the insecticides were quantified with the help of modified QuEChERS extraction method using LC-MS/MS in MRM mode and GC-ECD respectively. The method was sensitive to set the limit of quantification at 20 and 50 ng g⁻¹ in chilli for emamectin benzoate and fipronil respectively. The residue of emmamectin benzoate at both the doses dissipated completely after 1^st day. Kinetic studies revealed that the dissipation of fipronil followed the first-order kinetics with half-life of 0.74–0.98 d. Its pre-harvest interval was calculated as 7 d (for standard recommended dose) considering the EU MRL and the chilli fruits harvested after that time were found safe for human consumption.