Determination of Organochlorine Pesticides in Fish by GC with Dual-Column and Dual-ECD

GC with dual-column and dual-ECD was applied to the determination of 10 organochlorine pesticides in fish, including hexachlorobenzene, α-BHC, β-BHC, γ-BHC, δ-BHC, heptachlor, p,p'-DDE, o,p'-DDT, p,p'-DDD and p,p'-DDT. After the samples were extracted by oscillation with hexane, the extract was cleaned-up with self-made acidic silica gel column and the purified solution was analyzed by GC with dual-column (DB-35MS and DB-5) and dual-ECD system. The linearity ranges of 10 organochlorines were all 5.0-250 μg·L^-1, with detection limits (3.143s) in the range of 0.2-1.2 μg·kg^-1. Recovery rates obtained by standard addition method were in the range of 85.7%-121% and RSDs (n=6) were within 16%.