title: Gas chromatographic determination of fumigant residues in stored grains, using isooctane partitioning and dual column packings.
abstract: A gas chromatographic (GC) procedure for determining fumigants in grains was developed. Fumigants were leached from grain samples with the official AOAC method using acetone-water (5 + 1). They were then partitioned from the leachate with isooctane, yielding a dry, stable extract that was analyzed by GC. Fortified sample recoveries ranged from 90 to 100%. Two GC columns were used, 20% OV-101 and 20% OV-225/20% OV-17 (2 + 1). These columns gave dissimilar retention profiles and baseline resolution for the 7 fumigants investigated: chloroform, ethylene dichloride, carbon tetrachloride, trichloroethylene, chloropicrin, ethylene dibromide, and tetrachloroethylene. Further tests showed that grain samples could be screened for fumigant residues by direct injection of the acetone-water leachates obtained using the AOAC method.
mesh_terms: D002849:Chromatography, Gas; D002523:Edible Grain / Q000032:analysis*; D010573:Pesticide Residues / Q000032:analysis*
chemical_list: D010573:Pesticide Residues