采用CP-8ms毛细管色谱柱、直接加热—静态顶空—气相色谱/质谱联用法测定土壤中苯系物，并对顶空条件进行了优化。结果表明，装有10 g土壤样品的20 ml顶空瓶在95℃加热阱中以500 r min-1振摇20 s，停90 s，并平衡15 min，即可达到最佳脱附效果；并以不含待测苯系物的新鲜土壤制作校准样，外标法定量。该方法的精密度为2.35％～7.27％，检出限为0.23～1.35µg kg-1，各目标物的标准曲线线性相关系数r为0.9933～0.9980，加标样品回收率为74.2%～123%，可满足有机分析的要求。%BTEXs(Benzene,Toluene,Ethylbenzene & Xylene)as a kind of pollutants in the hunman living environment,like soil,could cause serious harm to human health. In this study an analytical method of BTEXs in soil samples was developed to determine these pollutants in the soil in a simple,convenient and environment friendly way. Soil samples contaminated with BTEXs were determined with CP-8 ms capillary column by Static Headspace-Gas Chromatography/Mass spectrometer(HS-GC/MS)under modified conditions. The optimal procedure goes:put fresh soil samples in 20 ml flasks,10 g each,and have them heated at 95 ℃ in the hot shakable incubator,agitated at rate of 500 r min-1 for 20 s,kept still for 90 s subsequently, and after 15 mins incubation the whole system reaches equilibrium. The BTEXs detection limit of the method varied in the range of 0.23~1.35 µg kg-1;and the standard curve correlation coefficient(r)of each BTEXs target ranged at 0.993 3~0.998 0. The sample recovery rate lingered in the scope of 74.2%~123% with the method precision varying in the range of 2.35%~7.27%(n=7). All demonstrate that the method meets the requirements of organic analysis.
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