Determination of Hexachlorobenzene in Soils by Dispersive Solid-phase Extraction and Gas Chromatography-mass Spectrometry

A quick,easy,cheap,effective,rugged and safe method was improved to analyze hexachlorobenzene (HCB) residues in soils by dispersive solid-phase extraction and gas chromatography-mass spectrometry (GC-MS).HCB residues in soils was extracted with acetone/hexane (1∶ 1,v/v) under ultrasonic extraction,and cleaned up on primary secondary amine (PSA) by removing the polar matrix components or interferences.GC-MS was then used for quantitative and confirmatory analysis of HCB.Linear calibration curves were obtained for HCB with a concentration range of 0.05~5 mg/L (R2=0.999 5).The limit of detection (LOD) of this method is 0.3 μg/kg,LOQ is 0.9 μg/kg.Recoveries of 106.6％,108.2％和108.1％ have been achieved at three concentrations of 0.89,1.78 and 8.90 mg/kg,respectively.Using this method we got the information of HCB residue in the soils from HCB manufacturing factories.The sample sites were below the soil surface from depth of 1 m to 10 m.The results showed the concentration of HCB in the soils at the residue levels from 2.3 mg/kg to 25 912 mg/kg.Most concentrations of these HCB samples exceeded the MRLs of HCB for agricultural soils.