Determination and risk assessment of tetraniliprole and spirotetramat residues in okra using LC-MS/MS

Abstract

A suitable and efficient multi-residue methodology was validated for the determination of tetraniliprole and spirotetramat along with their metabolites in okra. The dissipation of tetraniliprole, BCS-CQ 63359, spirotetramat, spirotetramat mono-hydroxy, spirotetramat keto-hydroxy, spirotetramat cis-enol, and spirotetramat-enol glucoside was assessed in okra whole fruit and soil after three foliar sprays of combination formulation of tetraniliprole 120 G/L and spirotetramat 240 G/L SC at 375 and 469 mL ha⁻¹. The recoveries obtained for analytes were within the acceptable range of 70–120 per cent. No significant effect of okra matrix was observed for all the analytes. The estimation of the residues was carried out on LC-MS/MS with LOQ of 0.01 mg kg⁻¹ for all analytes. Total average initial deposits of tetraniliprole at 375 and 469 mL ha⁻¹ doses in okra were 0.04 and 0.08 mg kg⁻¹, whereas BCS-CQ 63359 was detected below LOQ (0.01 mg kg⁻¹). Total mean initial deposit of spirotetramat were found to be 0.08 and 0.13 mg kg^-¹ , respectively. Residues of tetraniliprole, spirotetramat and spirotetramat-enol dissipated below LOQ at 5, 1 and 3 days of last foliar application, respectively. Dietary risk was worked out by comparing TMRC with MPI and TMRC values were observed to be less than MPI.