A method was developed for simultaneous determination of 18 pesticide residues in soils, including hexachlorocyclohexanes (HCHs), dichlorodiphenyltrichloroethanes (DDTs) and other 10 kinds of pyrethroid. The soil samples were distilled with Accelerated Solvent Extraction (ASE) and extracted by hexane-acetone-H3PO4 at extraction temperature of 100℃ and pressure of 10.3 Mpa. The distilled solutions were purified by solid phase extraction (SPE). The purified solutions were injected into Gas Chromatography-Mass Spectrometry (GC-MS) by using programmed temperature vaporization (PTV) and large volume injector (LVI). If the spiked level was 10-20 μg/kg, the recoveries of target compounds were 80.55% -96.33% and the relative standard deviations (RSDs, n =6) were 3.21% -7.34%. If the spiked level was 20-40 μg/kg, the recoveries were 80.55% -103.76% and RSDs (n=6) were 2.56% -5.78%. If the spiked level was 40 -80 μg/kg, the recoveries were 81.56% -95.38% , RSDs(n =6) were 2.19% -5.88%. The method detection limits were 0.11 -2.38 μg/kg, RSDs (n =3) were 4.94% -8.74% for real samples. The method is simple and rapid with high sensitivity making it suitable for simultaneous determination of residues of benzex and DDTs and pyrethroid in soils.%采用正己烷-丙酮-磷酸混合溶剂为提取剂,在萃取温度100℃、压力10.3 MPa条件下,用快速溶剂萃取仪提取土壤样品,石墨碳黑氨基固相萃取柱净化,PTV大体积进样,气相色谱-质谱联法同时检测六六六(HCHs)、滴滴涕(DDTs)和10种拟除虫菊酯类农药(联苯菊酯、甲氰菊酯、氯氟氰菊酯、氯菊酯、氯氰菊酯、氟氯氰菊酯、氟氨氰菊酯、氰戊菊酯、氟氰戊菊酯、溴氰菊酯)共18种农药残留.在10～20μg/kg的添加浓度下,目标化合物平均回收率为82.84％ ～96.33％,相对标准偏差(RSD,n=6)为3.21％～7.34％；在20～40 μg/kg的添加浓度下,目标化合物平均回收率为80.55％～103.76％,RSD(n =6)为2.56％～5.78％；在40 ～80 μg/kg的添加浓度下,目标化合物平均回收率81.56％ ～95.38％,RSD(n=6)为2.19％～5.88％.方法检出限为0.11～3.40 μg/kg,实际样品检测的RSD(n=3)为4.94％～8.74％.方法简单快速、灵敏度高、准确度好,可以满足土壤中HCHs、DDTs和拟除虫菊酯类农药残留的实际检测需要.
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