Determination of Acidic Herbicides and Related Compounds in Water and Soil by Capillary Gas Chromatography Using a Nitrogen-Phosphorus Detector
Abstract Methods are described for the determination of acidic herbicides and related compounds in water and soil. Eight acidic herbicides and related compounds were extracted from water using either dichloromethane or an XAD-2 resin column. The acidic moieties were derivatized with 2-cyanoethyldimethyl(diethyl)aminosilane. The derivatized compounds were separated using capillary gas chromatography and quantitated using a nitrogen-phosphorus detector. Extraction from water using dichloromethane or an XAD-2 resin column resulted in recoveries > 90% at 0.1 ppb with an average coefficient of variation (CV) of 6%. In soils extracted with aqueous acetonitrileacetic acid and partitioned into dichloromethane, recoveries at 500 ppb were > 75% with an average CV of 3.3%. The methods are rapid and there are few interferences.