气相色谱法测定土壤中14种有机氯农药

目的:采用气相色谱法建立土壤样品中有机氯农药的检测方法。方法:土壤样品干燥过筛后,对比了旋涡振荡、超声、匀浆三种样品提取方式,采用固相萃取小柱净化,经气相色谱(ECD)检测。结果:超声提取效果优于其他两种提取方式,14种有机氯农药在0.005μg/ml～1.0μg/ml的浓度范围内线性良好(R>0.99);添加浓度在5.0μg/kg、50μg/kg水平下,14种OCPs的平均回收率范围分别为80.2%～112%、80.6%～110%,相对标准偏差范围分别为4.77%～11.3%、1.41%～8.12%,方法检出限为0.80μg/kg～1.51μg/kg。结论:该方法操作简便,灵敏度高,能够满足土壤中有机氯农药残留的检测。

Study on determination of organochlorine pesticides in soil by gas chromatography

Objective:To establish a method for the determination of organochlorine pesticides in soil by GC.Methods: Soil sample was extracted by using three different ways(ultrasonic extraction,vortex extraction and homogenate) after drying,then purified by solid-phase extraction(SPE) cartridges,finally determined by GC(ECD).Results: Ultrasonic extraction provided better recovery than the other two ways.The method showed good linearity in a range from 0.005 μg/ml to 1.0 μg/ml(R>0.99),and the detection limit of fourteen OCPs was 0.80 μg/kg～1.51 μg/kg.The recoveries at 5.0 μg/kg and 50 μg/kg in soil sample were 80.2%～112% and 80.6%～110%,the relative standard deviation were 4.77%～11.3% and 1.41%～8.12% respectively.Conclusion: This study provided a simple,accurate and sensitive method for determining the organochlorine pesticides in soil.