DETERMINING 10 SYNTHETIC PYRETHROIDS IN LETTUCE AND GROUND MEAT BY USING ION-TRAP MASS-SPECTROMETRY AND ELECTRON-CAPTURE GAS-CHROMATOGRAPHY

Conventional extraction procedures with acetonitrile were compared wit h supercritical fluid extraction (SFE) with CO2 for determining 10 pyr ethroids in fortified lettuce and meat samples. Because SFE utilized a minimal cleanup procedure, nonvolatiles may accumulate on the capilla ry column in both the gas chromatography-ion trap mass spectrometry (G C-ITMS) and electron capture (EC) detection modes shortening the lifet ime of the columns after multiple injections. The GC-ITMS method prove d satisfactory for analysis of lettuce whereas EC-GC proved more suita ble for residue analysis of meat samples. Improvements in multiresidue methods for monitoring of synthetic pyrethroids in raw agricultural c ommodities should aid in registration and reregistration activities.