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[目的]建立简便易行的气相色谱分析方法为土壤中666和DDT残留的检测提供可靠的检测手段。[方法]以唐山郊区土壤为研究对象,采用梅花样布点方式采集土壤,将采来的土壤样品风干、磨细、过筛、混匀、装瓶,采用超声波振荡提取技术对样品进行提取,用正己烷-石油醚-丙酮混合液浸泡土壤样品,超声波振荡提取1h,提取两次,于80℃水浴中蒸至10ml左右,浓硫酸磺化,过层析柱,于80℃水浴中蒸干,用1ml正己烷定容,毛细管柱气相色谱-电子捕获检测器检测。[结果]在优化的试验条件下,8种有机氯农药残留组分在25min内能够很好的分离,其质量浓度与色谱峰面积在0.001～0.5μg·ml-1的浓度范围内呈线性关系,检出限小于2.99μg·ml-1,方法的日内精密度0.40%～9.21%,日间精密度0.77%～11.32%,方法加标回收率62.7%～120%。[结论]该方法操作简单,可用于土壤中有机氯的监测。
[Objective] The research aimed to establish a simple and easy method for gas chromatographic analysis to provide a reliable method for the detection of 666 and DDT residues in soil. [Method] With the soil of Tangshan suburb as the research object, the soil was collected by plum blossom pattern. The soil samples were air-dried, ground, sieved, mixed and bottled. The samples were extracted by ultrasonic vibration extraction. Soak the soil samples with n-hexane-petroleum ether-acetone mixture for 1 h under ultrasonic oscillation, extract twice and evaporate to about 10 ml in a water bath at 80 ° C. The mixture is sulfonated with concentrated sulfuric acid and passed through a chromatographic column. With 1ml n-hexane constant volume, capillary gas chromatography - electron capture detector detection. [Result] Under the optimized experimental conditions, the residual components of 8 kinds of organochlorine pesticides could be well separated within 25 min. The mass concentration and the chromatographic peak area showed a linear relationship in the range of 0.001-0.5 μg · ml-1 , The detection limit was less than 2.99μg · ml-1, the method of intra-day precision 0.40% ~ 9.21%, intra-day precision 0.77% ~ 11.32%, the method of spike recovery 62.7% ~ 120%. [Conclusion] The method was simple and could be used for the monitoring of organic chlorine in soil.