Determination of Multiple Pyrethroid Insecticides in Chrysanthemum Flower

A simplified method for determining four pyrethroid insecticides (fenpropathrin, cypermethrin, fenvalerate, and deltamethrin) in the Chinese herbal medicine (chrysanthemum flower) is described. Standards were fortified into chrysanthemum flower (5g) with three levels, 1, 0.1 and 0.01mg/kg. The pyrethroid insecticides are extracted with petroleum ether and cleaned up with neutral aluminum oxide. The extracts are analyzed by gas chromatography equipped with electron capture detector (ECD). Analysis of fortified chrysanthemum flower ( n =5) shows mean recoveries ranged from 86%～104% at 1 mg/kg level, 87%～95% at 0.1 mg/kg level and 81%～99% at 0.01 mg/kg level. The minimum detector response ranged form 8.3×10-4 ～2.8×10-3 ng and minimum detectable concentration ranged from 0.83～2.82 μg/kg. The method is rapid, simple, sensitive and is applicable to the determination of fenpropathrin, cypermethrin, fenvalerate, and deltamethrin in chrysanthemum flower.