Analysis of pyrethroid residues in fishery water by Gas Chromatography

A method for determining tefluthrin,bifenthrin,fenpropathrin,cyhalothrin,permethrin,cyfluthrin,cypermethrin,fenvalerate,tau-fluvalinate,deltamethrin residues in fishery water was developed.The pyrethroids were extracted by petroleum ether,dehydrated by anhydrous sodium sulfate,concentrated and then analyzed by gas chromatography with electron capture detector(GC-ECD).The linear range of tefluthrin was 2.5～100ng/mL and the other nine were 5～200ng/mL(r≥0.9954).When spiked with 0.05μg/L,0.5μg/L,1μg/L,the average recoveries ranged from 73.8% to 100.2% and their relative standard deviations(RSD)were between 2.53% and 10.3%.The limits of detection(LOD) and limits of quantitation(LOQ) for all pyrethroids were in the range from 0.125～2.5ng/L and 0.025～0.05μg/L separately.This method is simple,reliable and can be applied in the detection of pyrethroid in fishery water.