Determination of multiple organophosphorous pesticide residues in water by dual-column gas chromatography coupled with solid phase extraction

To avoid the case of false positive when analyzing by single column,the dual-column gas chromatography coupled with solid phase extraction was applied to the multi-residue determination of organophosphorous pesticides in environmental water.The organophosphorous pesticides were extracted from water with HLB solid phase extraction cartridges and then eluted.After concentrated,the eluents were detected by GC-FPD with DB-35MS and HP-5 capillary columns.The average recoveries of 5 replicates for analytes ranged from 86.1% to 118%,with relative standard deviations between 3.2% and 6.8%.And the method detection limits were within the range of 20 ng/L to 40 ng/L.The results showed that the proposed method is suitable for the determination of trace amounts of multiple organophosphorous pesticide residues in environmental water.