Analysis And Determination Of Pesticide Residues In Import And Export TCM

Pesticide residues are toxic metabolites, degradation products andimpurities remaining in the organism, agricultural and sideline products andenvironment after using the pesticides. Pesticide residues exceeded thestandard are not only harmful to people’s health, damage the interests ofconsumers, but also become the bottleneck of TCM into the internationalmarket. At present, the United States and Europe put forward higherrequirements of TCM pesticide residue limits, and develop maximumresidual levels, pesticide residues in the import and export of TCM must belower than MRLs of all countries. Excessive pesticide residues seriously lagthe pace of TCM modernization and internationalization.Different kinds of pesticide residues accumulated in different parts ofTCMs. Residues of OCPs and PPS are mainly derived from the rootabsorption in the soil, so the OCPs and PPs left more in the rhizome,however, OPPs in the environment are easier to decompose. OPPs residuesmainly remain in the fruits TCM, which was caused by unreasonable andnumerous pesticides spray.The current standards for pesticide residues of TCM only include a few pesticides just as BHC, DDT, and quintozene, which can not apply in varietyof pesticide residues in different TCM. So an accurate, reliable, sensitive,stable method for simultaneous determination many kinds of pesticideresidues in rhizome TCM and fruits TCM established in this study is veryimportant and necessary for the modernization and internationization studyof TCM.Part Ⅰ Determination of27kinds of OCPs and PPs in import andexport rhizome TCMObjective: To establish GC method for determination of27kinds ofOCPs and PPs in rhizome TCM(Common yam rhizomes, Radix PuerariaeLobatae, Radix Ginseng, Ternate Pinellia, Chinese Thorowax Root, PiloseAsiabell Root). Methods: The analytes were separated on a30m×0.25mm×0.25μm film thickness DB-1701capillary column. The carrier gas wasnitrogen at a flow rate of1.0mL/min. The oven temperature was initially at90℃for1min, increased at a rate of40℃/min up to150℃, held for5min;increased at a rate of2℃/min up to210℃; increased at a rate of10℃/minup to280℃and held for20min. The injection volume was1μL. Results:The calibration curve was linear from10to500μg/L with good linearity(γ≥0.9958), limit of detection were between0.09and1.82μg/L. Therecovery of the pesticides spiked in various TCMs at3spiked levels rangedfrom80.1%to98.0%, with RSDs ranged from2.03%to9.17%. Conclusion:The method has high sensitivity and accuracy, good repeatability, which can be used for the determination of the27kinds of OCPs and PPs in rhizomeTCM.Part Ⅱ Determination of20kinds of OPPs in import and exportfruits TCMObjective: To establish GC method for determination of20kinds ofOPPs in fruits TCM (Dried tangerine peel, Foeniculum vulgare, JaveAmonum Fruit, Fructus Arctii, Lycium chinense, Dried red Jujubes).Methods: The analytes were separated on a30m×0.25mm×0.25μm filmthickness DB-1701capillary column. The carrier gas was nitrogen at a flowrate of1.2mL/min. The oven temperature was initially at70℃for1min,increased at a rate of10℃/min up to260℃, held for3min; increased at arate of20℃/min up to275℃held for7min. The injection volume was2μL.Results: the calibration curve was linear from0.01to2.00mg/L with goodlinearity (γ≥0.9966), limit of detection were between0.66and5.78μg/L.The recovery of the pesticides spiked in various TCMs at3spiked levelsranged from84.3%to98.1%, with RSDs ranged from2.32%to9.23%.Conclusion: The method has high sensitivity, high accuracy, goodrepeatability, which is applicable to the determination of the20kinds ofOPPs in fruits TCM.