毛细管柱气相色谱法同时测定蔬菜和水果中16种有机磷农药残留量方法的建立与应用

Establishment and Application of Simultaneous Determination of 16 Organophosphorus Pesticide Residues in Vegetables and Fruits by Capillary Column Gas Chromatography

目的建立同时测定16种有机磷农药的毛细管柱气相色谱方法,了解自贡市蔬菜水果等农副产品有机磷农药污染状况,并针对性开展风险监测提供技术保障。方法采用有机溶剂萃取样品中有机磷农药,经毛细管色谱柱分离,气相色谱测定蔬菜和水果中有机磷农药残留量。结果通过试验建立起了样品经过匀浆后,经丙酮提取,提取液经二氯甲烷提取,将提取液经旋转蒸发仪浓缩至约2 ml后,用二氯甲烷定容至10 ml,进样经HP-1石英毛细管柱分离待测成分,溶剂分流,用FPD检测器二阶程序升温气相色谱仪测定蔬菜和水果中有机磷农药残留量的色谱条件测定16种有机磷待测组分在0.01~2.00μg/ml范围内呈良好线性关系(r>0.997)。在萝卜样品中加入0.1μg/ml各组分标准物1.00 ml进行重复性测定(n=6),其RSD为4.57%~9.95%,检出限在0.002~0.008 mg/kg;定量限在0.007~0.028 mg/kg。向样品中加入每组分浓度为0.20μg/ml、0.80μg/ml和1.60μg/ml的16种有机磷混合标准物1.00 ml进行回收率试验,平均回收率在75.2%~95.3%之内。用该色谱分析条件对100件蔬菜和水果进行了应用验证,部分蔬菜检出了一种或多种有机磷农药残留,阳性率在12%~36%。结论本方法对敌敌畏、久效磷、甲拌磷、乐果、二嗪磷、稻瘟净、甲基对硫磷、杀螟松、甲基嘧啶磷、马拉硫磷、倍硫磷、对硫磷、水胺硫磷、喹硫磷、克线磷、乙硫磷共16种农药残留分离效果好,灵敏度高,定量准确,可用于测定蔬菜、水果中的这16种有机磷农残。

Objective To establish simultaneous determination of 16 organophosphorus pesticides by capillary gas chromatography and to understand the pollution status of organophosphorus pesticides in agricultural products such as vegetables and fruits in Zigong,so as to provide technical support for risk monitoring. Method The study extracted the organophosphorus pesticides from samples by using organic solvents, separated them by capillary column, and determinate the organophosphorus pesticide residues in vegetables and fruits by gas chromatography. Results The test sample was established homogenized, extracted with acetone, then extracted with dichloromethane,the extract was evaporated and concentrated to about 2 ml,made up to the volume of 10 ml by using methylene chloride,injected the sample by HP-1 quartz capillary column to test the components,and conducted the solvent diversion,then the second-order temperature-programmed gas chromatograph with FPD detector was used to determinate and indicate the 16 kinds of organic phosphorus fractions in 0.01-2.0 μg/ml was linear within the range(r>0.997) in fruits and vegetables of organophosphorus pesticide residues of the chromatographic conditions. This study made repeatability test(n=6) by adding the 0.1 μg/ml standards of each component to radish samples, the RSD was 4.57%~9.95%, the detection limit was 0.002~0.008 mg/kg, and the quantitation limit was 0.007~0.028 mg/kg. The paper made recovery test by adding 1.00 ml mixture of 16 kinds of standard materials with the concentration of 0.20 μg/ml, 0.80 μg/ml and 1.60 μg/ml to the samples, the average recovery was 75.2% to 95.3%. The application verification was conducted in 100 vegetables and fruits under this chromatographic conditions,some vegetables had been detected with one or more organophosphorus pesticide residues,the positive rate was about 12% to 36% in these samples. Conclusion The method is effective,sensitive,and accurate for 16 kinds of pesticide residues,such as the dichlorvos,monocrotophos,phorate,dimethoate,diazinon,rice blast,methyl parathion,fenitrothion,pirimiphosmethyl,malathion,fenthion,parathion,acesulfame,quetiapine,gram phosphorus,and ethion,and can be used for the determination of 16 kinds of organic phosphorus residues in vegetables and fruits.