Simultaneous determination of residues of pyrethroid pesticides in aquatic products by gas chromatograohy

Gas chromatography with electron capture detection method was developed for the determination of 6pyrethroids residues in aquatic products.The sample was extracted with cyclohexane:ethyl acetate(1:1,V:V),separated with liquid-liquid partition and cleaned up with Florisil solid-phase extraction cartridges using acetone:n-hexane(1:9,V:V)as eluent.The eluent was blown to dryness under a stream of nitrogen,was then injected into the GC system to quantitative analysis.Under the optimal conditions,the detection limits of this method for 6pyrethroids residues were 1.1～2.4μg/kg,with the relative standard deviations ranging from 1.1% ～5.2%(n=5) and the recovery rates were from 85.7%～108.1%.