ABSTRACT
A method for determination of PCDD/Fs, PCBs and PCNs in soil sample was developed by using accelerated solvent extraction (ASE)-silica gel column cleanup-basic alumina column separation coupled with GC-MS/MS.The sample was extracted by ASE with Hexane-methylene chloride (Hex-DCM, 50∶50, V/V) at 120℃.The basic alumina column was used to separate PCDD/Fs, PCBs and PCNs.The extracts were eluted with Hex-DCM (95∶5, V/V) to obtain PCBs and PCNs, followed by Hex-DCM (50∶50, V/V) to obtain PCDD/Fs.The limits of detection (LOD) were in the range of 0.04-0.25 μg/L, 0.10-0.20 μg/L and 0.01-0.05 μg/L for PCDD/Fs, PCBs, PCNs, respectively.The relative standard deviations (RSDs) of average relative response factors (RRF) were below 13%.The recoveries of 13C-labeled internal standards of the three classes of analytes were 50%-95%, 51%-103% and 49%-74%, respectively.Concentrations of ∑PCDD/Fs, ∑PCBs and ∑PCNs in soil samples were 16.1-1148 pg/g, 6.6-152.6 pg/g and 10.9-99.5 pg/g, respectively.The results were consistent with that of high resolution mass spectrometer.