Determination of spinetoram residues in rice field environment by HPLC combined with QuEChERS method, residue elimination and final residues

Spinetoram, a novel insecticide developed by Dow AgroSciences, USA, was the focus of this study. The aim of this study was to establish a methodology for determining the digestion dynamics and final residue concentrations of spinetoram in rice soil, brown rice, rice hulls, and rice plants. This was achieved through the utilization of high-performance liquid chromatography(HPLC) in combination with QuEChERS residue analysis. The results showed that the concentrations and peak areas of spinetoram showed a good linear correlation(R2>0.99) in a certain concentration range, and the LOD and LOQ values ranged from 0.0026 to 0.0066 mg/kg and 0.0103–0.0256 mg/kg, respectively.The average intraday recoveries ranged from 88.34 % to 100.64 % with relative standard deviations ranging from 0.93 % to 6.77 %, while interday recoveries ranged from 89.45 % to 98.34 % with relative standard deviations ranging from 1.32 % to 6.18 %. Dissolution kinetics in paddy soil and rice plants followed one-stage kinetics with half-lives ranging from 6.65 days to 6.92 days and from 3.91 days to 5.49 days respectively. The developed simple and sensitive analytical method facilitates the safe application of spinetoram in rice field environments while minimizing potential environmental risks.