SOLID-PHASE EXTRACTION OF HERBICIDES FROM WELL WATER FOR DETERMINATION BY GAS-CHROMATOGRAPHY MASS-SPECTROMETRY

A simple, rapid method for isolating herbicides from well water was developed using disposable octadecyl (C18) solid-phase extraction columns. Deuterium-labeled internal standards were used to compensate for any losses that may have occurred during sample preparation owing to matrix effects. Detection by capillary gas chromatography-mass spectrometry in the selected ion monitoring mode minimized the frequency of false-positive results. The accuracy of the method was ± 5% at concentrations > 0.20μg l-1 for four of the five herbicides studied. © 1990.