RAPID, DIRECT DETERMINATION OF IMIDAZOLINONE HERBICIDES IN WATER AT THE 1 PPB LEVEL BY LIQUID-CHROMATOGRAPHY ELECTROSPRAY-IONIZATION MASS-SPECTROMETRY AND TANDEM MASS-SPECTROMETRY

The imidazolinones are a significant new class of low-use-rate, reduce d-environmental-risk herbicides for protection of a wide variety of ag ricultural crops. Current analytical methodologies for the determinati ons of individual imidazolinones in water at the 1 ppb level involve p rocessing several hundred milliliters of water through a series of sol id-phase extraction cartridges and solvent-partitioning steps. By comb ining liquid chromatography with electrospray ionization mass spectrom etry or electrospray ionization tandem mass spectrometry, all imidazol inones can be monitored simultaneously at the 1 ppb level with only a simple filtration prior to analysis. Recoveries from tap, lake, and we ll waters were essentially quantitative for each imidazolinone in both modes of analysis.