Residue Dissolution And Dietary Risk Assessment Of Dinotefuran In Cabbage And Soil

Dinotefuran is the third generation of neonicotinoid insecticides.It has a broad insecticidal spectrum and high activity.It has a significant effect in preventing yellow stripe flea beet on cabbage and has a wide application prospect in agricultural production.At present,the residue detection of dinotefuran and its metabolites DN,UF in cabbage has not been reported.In this paper,QuEChERS extraction and purification methods for dinotefuran and its metabolites DN and UF in cabbage and soil were established.The samples were extracted with 10% acetic acid and acetonitrile,purified by PSA,and detected by LC-MS/MS.The linear correlation coefficients of the calibration curves for the compounds in the two matrices ranged from 0.992 to 1.000 with a linear range of 0.005 to 1 mg/kg,and the LOD was 0.015 ng.The recoveries of the three analytes were between 72.3% and 107.8%,RSD was between 0.5% and 5.1%,and the LOQ was 0.05 mg/kg.This method is suitable for the detection of dinotefuran,DN and UF in cabbage and soil.In order to investigate the effects of different doses and times on the diuretic amine and DN and UF residuals,dinotefuran was field-tested in two years and three regions in cabbage and soil,mainly from digestion dynamics and final residue were compared in several aspects.Digestion dynamic test results showed that the half-life of dinotefuran in cabbage and soil was 4.8 d to 20.4 d,and the correlation coefficient was between 0.515 and 0.937.The degradation rate in soil was relatively slow.Residue test results show that the dose,number of times and the interval between harvests are different,and the residue will be different.When the dose was increased to 1.5 times,the average residue increased by 20.4%;when the application was twice,the average residue increased by 91.5% compared with the application;at the harvest interval of 5 and 7 d,the average residue The amount was 98.6% and 98.1% respectively for 3 days.Combining the residue data of pesticide field trials and the level of food intake,the dietary exposure risk assessment of pesticide residues in cabbage was performed.Dinotefuran has a NEDI value of 0.074 to 2.47 ?g/(kg bw·d),RQc values range from 0.04% to 1.2%,NESTI values between 0.667 to 17.6 ?g/(kg bw·d),and RQa values.For 0.07% to 1.8%,the chronic and acute risks are low and acceptable.