Kinetic Modeling of Chlorantraniliprole and Lambda-Cyhalothrin in Non-Flooded Soil Systems Using GC-MS/MS

A pot culture experiment evaluated the dissipation kinetics and ecological risk of a ready-mix formulation of chlorantraniliprole (9.30%) + lambda-cyhalothrin (4.60%) ZC in sandy loam soil under controlled non flooded conditions. Soil residues (0-10 cm) were monitored up to 90 days using GC-MS/ MS. QuEChERS outperformed MSPD, giving >85% recoveries. Both pesticides dissipated via first-order kinetics (R2 >0.97), with half-lives of 1.65-2.84 days (chlorantraniliprole) and 2.47-4.52 days (lambda-cyhalothrin). Residues persisted up to 60 and 45 days, respectively, depending on dose levels. Initial RQ values for Eisenia fetida (>1) indicated high risk but decreased to <0.1 as residues degraded. Overall, the study reveals rapid dissipation, short-lived ecological risk, and provides essential data for environmental safety evaluation and optimized pesticide application strategies.