Dissipation and risk assessment of ready-mix formulation volium flexi (Chlorantraniliprole and thiamethoxam) residues in cowpea

Dissipation of ready-mix combination insecticide Voliumflexi (Chlorantraniliprole 8.8% + thiamethoxam 17.5% SC) @ 150 g a.i ha in cowpea was studied in 2017 at AINP on Pesticide Residues, Vellayani, Kerala Agricultural University. Samples were collected on 0, 1, 3, 5, 7, 10 and 15 days after spraying and residues were extracted by QuEChERS method and estimated by LCMS/MS. The results revealed that chlorantraniliprole was dissipated up to 7 days with an initial concentration of 0.27 mg kg thereafter reached to below detectable level with a half-life of 5.34 days. Whereas, the residues of thiamethoxam were dissipated with initial deposit of 0.64 mg kg and no residues were detected after 10 day of application and half-life was 3.01 days.