Separation and Determination of Chlorinated Paraffin and Polychlorinated Biphenyls in Sediment by GC-MS

KeyWord:GC-MS  short-chain chlorinated paraffin£¨SCCPs£©  medium-chain chlorinated paraffin£¨MCCPs£©  polychlorinated biphenyls£¨PCBs£©  sediment

Abstract:

      A method was established for the separation and determination of chlorinated paraffin£¨CPs£© and polychlorinated biphenyls£¨PCBs£© in sediment.CPs and PCBs were firstly extracted with dichloromethane from sediment£¬then CPs were separated from PCB via a cleanup procedure with complex Florisil/Silica column.The fraction containing PCBs was eluted with 80 mL hexane£¬followed by the elution of fraction containing CPs with 60 mL dichloromethane.CPs were determined by GC-ECNCI-LRMS under selective ion monitoring mode and PCBs were analyzed by GC-EI-MS£¬and quantified by the internal standard method.The procedure of sample pretreatment£¬amount of dispersant and instrument conditions were also optimized.The result indicated that recoveries of technical mixture of CP52 and 22 PCB standards in spiked matrix ranged from 86% to 99%£¬with RSDs less than 10%.The method detection limits for short-chain chlorinated paraffin£¨SCCPs£© and medium-chain chlorinated paraffin£¨MCCPs£© were in the ranges of 0.144-3.47 ng/g and 0.530-2.24 ng/g£¬respectively.The method was applied in the determination of CPs and PCBs in six sediments from Dongjiang River.The concentrations of SCCPs£¬MCCPs and PCBs were in the ranges of 0.245-1.58 ¦Ìg/g£¬0.538-1.83 ¦Ìg/g and 1-100 ng/g£¬respectively.Therefore,the method was rapid£¬sensitive and accurate£¬and was suitable for the reliable investigation of CPs and PCBs in sediment as well as in soil samples.