Simplified Extraction and Cleanup for Multiresidue Determination of Pyrethroid Insecticides in Chrysanthemi

A simplified method for determining 4 pyrethroid insecticides (Fenpropathrin, Cypermethrin, Fenvalirate, and Deltamethrin) in Chrysanthemi is described. Standards were fortified in to Chrysanthemi (5g) with two levels, 0.1-1 pp m the pyrethroid pesticides are extracted with petroleum ether and cleaned up by natural aluminum oxide. The extracts are analyzed by gas chromatography equipped with electron capture detector (ECD). Analysis of fortified Chrysanthemi (n = 3) shows recovery range from 99-102 % at 1 pp m level and 93-104 % at 0.1 pp m level. The coefficient of variation of the method at 1 st level was 0.12 and 0.14 for 2 ed level. The detection limits of the method ranged from 0.04pp b to 28 pp b. The method is rapid, sample, and sensitive and is applicable to the determination of Fenpropathrin, Cypermethrin, Fenvalirate, and Deltamethrin in Chrysanthemi.