Evaluation of electrolytic conductivity detection for gas-liquid chromatographic screening of some organonitrogen herbicides and fungicides in foods.

Electrolytic conductivity detection for the gas-liquid chromatographic (GLC) screening of 15 organonitrogen herbicides and fungicides was investigated. Spiked samples of crop material was extracted with acetone and the filtered sample extracts were partitioned with methylene chloride-petroleum ether (1+1) followed by second and third extractions with methylene chloride. The combined organic extracts were evaporated to dryness and the residues were dissolved in hexane for cleanup on a 2% deactivated Florisil column. The pesticide fractions were determined directly by GLC. All pesticides could be detected at 0.1 ppm in the foods studied.