Dissipation kinetics, effect of household processing, and dietary risk assessment of the insecticide chlorantraniliprole residue in bitter gourd and soil

A single quadrupole liquid chromatography-mass spectrometry (LC-MS) method was validated to determine the insecticide chlorantraniliprole residues in bitter gourd fruit, juice, and soil, according to the SANTE guidelines. A linear curve was obtained (R2 > 0.99) with LOD and LOQ at 0.003 mg kg-1 and 0.01 mg kg-1. The accuracy (87–102%) and precision (RSD <5%) of the method was found to be satisfactory. The  dissipation pattern of chlorantraniliprole 18.5% SC was studied by spraying twice at ten days intervals, at the recommended dose (X) (25 g a.i. ha-1), and double the recommended dose (2X) (50 g a.i. ha-1). The initial deposit on bitter gourd was 0.72 and 1.41 mg kg-1 and residues persisted up to 15 and 20 days with a half-life of 2.44 and 2.79 days at X and 2X doses, respectively. Simple decontamination techniques were found to reduce residues to the extent of 30 to 80 per cent. The reduction of chlorantraniliprole residues in bitter gourd juice was 40-50 per cent by different washing techniques. The estimated level of Risk quotient indicated (<1) chlorantraniliprole residues pose no dietary risk to consumers at the level detected.