With acetone and n-hexane as a solvent,under the condition of 100℃ of the temperature and pressure of 1 500 psi, extracted organochlorine pesticides from the soil with a rapid solvent extraction instrument,dehydrated and purified with molecular sieves,using retention time and selected ion qualitative mode,using the external standard method,organochlorine pesticides in the soil was measured by GC-MS. The detection limits were between 0. 000 4~0. 000 7 mg/kg and the correlation coefficient were more than 0. 998. Standard import soil were measured with high recoveries between 77. 1% to 105. 2% and the relative error were between -22. 9% to 5. 2%. The measurement results were in a certificate tolerance range. Using diatomaceous earth was spiked to high,medium and low concentration,and the spiked recoveries were between 84. 3% to 101. 5%,the relative standard deviation were of 0. 6% to 11. 4%. The result showed that The method is accurate and reliable method for the determination of the actual soil.%用丙酮和正己烷(体积比为1∶1)作溶剂,在100℃和1500 psi的压力下,用快速溶剂萃取仪从土壤中萃取出有机氯农药,用分子筛进行脱水和净化, GC-MS进行分析,对土壤中有机氯农药进行测定。方法的检出限为0.0004~0.0007 mg/kg,曲线的相关系数在0.998以上。对进口标准土进行测定,回收率为77.1％~105.2％,相对误差为-22.9％~5.2％,测定结果在证书允许误差范围内。用硅藻土制成高、中、低3个浓度级别的加标回收和精密度实验,加标回收率为84.3％~101.5％,相对标准偏差为0.6％~11.4％,表明方法准确可靠,方法用于实际土壤测定时发现土壤有不同程度的有机氯农药污染。
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