The Method Development Of Pesticide Residue Detection In The Tomato And Pesticide Residue Monitoring Of Tomato In Tianyang County Of Guangxi

Tomato is the pillar industry of vegetables in guangxi province. In this paper, several effective methods were developed for the determination of pesticide residue in tomato, and these developed methods were applied to determine the analytes in real market samples of Tianyang county, which was the largest tomato production base in guangxi province. This work could provide basic data for the quality and safety assessment of tomato industry in Guangxi.Developed the motheds for the determination of pesticide residue in tomato. Several effective methods were established for analysis of 39 pesticide (21 insecticides,8 fungicides, 9 herbicides,1 plant growth regulators) residues in tomato by liquid chromatography or gas chromatography. The samples were extracted with acetonitrile, and cleanup were performed by using SPE, PSA or MWCNTs, then the analytes were determined. The mothed for determination of 39 pesticides in tomato was confirmed by spiked and recovery test, and quantified by the method of matrix-matched external standard. The recoveries for all the pesticides studied were from 63.2%to 110.2%at the spiked concentration levels of low, medium and high (this setting took the MRL value as the center), with relative standard deviations (RSDs)<11.5%. The limit of quantitation (LOQ) was from 0.001 mg/kg to 0.05 mg/kg. The method could meet the requirements for pesticide residue analysis in each aspect of recovery, LOD and precision.Analysis of real samples. The analytical methodology developed were finally applied to analyse 480 tomato samples collected from baiyu town, tianzhou town, toutang town and nama town in tianyang county in October 2014-2015 March and October 2015-2016 March in harvest period. The target pesticides were detected in samples mainly for insecticides and fungicides, herbicides were not detected. The detected insecticides were mainly from collected samples in October and the detected in each month collected samples. The detected pesticides were chlorpyrifos, permethrin, deltamethrin, bifenthrin, procymidone, pyrimethanil, tebuconazole, cymoxanil, carbendazim and fludioxonil. The residues of these pesticides were detected in 0.005-0.06mg/kg, and they were not exceeded their maximum residue limits (MRL) in tomato.