Determination of Pesticides in Soils by Gas Chromatography-Ion Trap Mass Spectrometry

Abstract

Abstract A multiresidue method is reported for determination of a variety of chemical classes of pesticides (organochlorines, organophosphates, triazines, phenylureas, acetanilides, pyrethroids, carbamates, and miscellaneous others) in soils. Soil samples are extracted with an acetonitrile-water mixture, and the pesticides are partitioned into petroleum ether-diethyl ether for direct analysis by gas chromatography-ion trap mass spectrometry (GC-ITMS) with the mass spectrometer operated in the electron ionization mode. Recovery values determined for a fortification range of 20–1000 ppb were >80% for most of the pesticides. Detection limits determined in the full-scan mass spectrum mode were in the 1–10 ppb range for most analytes. This simple and rapid multiresidue method for determination of pesticides at trace levels in soils is appropriate for environmental behavior and pollution monitoring studies.