| Abstract
| - The applicability of supercritical fluid extraction (SFE) in pesticide multiresidue analysis (organohalogen,organonitrogen, organophosphorus, and pyrethroid) in soil samples was investigated. Fortificationexperiments were conducted to test the conventional extraction (solid−liquid) and to optimize theextraction procedure in SFE by varying the CO2 modifier, temperature, extraction time, and pressure.The best efficiency was achieved at 400 bar using methanol as modifier at 60 °C. For the SFE method,C-18 cartridges were used for the cleanup. The analytical screening was performed by gaschromatography equipped with electron-capture detection (ECD). Recoveries for the majority ofpesticides from spiked samples of soil at different residence times were 1, 20, and 40 days at thefortification level of 0.04−0.10 mg/kg ranging from 70 to 97% for both methods. The detection limitsfound were <0.01 mg/kg for ECD, and the confirmation of pesticide identity was performed by gaschromatography−mass spectrometry in a selected-ion monitoring mode. Multiresidue methods wereapplied in real soil samples, and the results of the methods developed were compared. Keywords: Pesticide multiresidue analysis; supercritical fluid extraction; capillary gas chromatography−mass spectrometric detection with selective ion monitoring; soil
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