Pesticide residues were extracted with 70% acetone and transferred to dichloromethane. Extracts were applied to open-column chromatography with florisil and alumina-N. The final extract was analyzed by gas chromatography with electron-capture detector(GC/ECD) and nitrogen-phosphorus detector(GC/NPD). Recoveries of the 17 organochlorine pesticides were ranged from 60.8 to 84.9% and those of 15 organophosphate pesticides, from 70.5% to 100.0%(except phosmet and azinphos-methyl). The minimum detectable levels of this analytical method were low(0.021-0.058㎎/㎏).

Organophosphate pesticides were extracted with 70% acetone and then transferred to dichloromethane. Extracts were applied to open-column chromatography with florisil The final extract was analyzed by gas chromatography with nitrogen-phosphorus detector(GC/NPD). Recoveries of the 18 organophosphate pesticides were ranged from 88.7% to 100.0% for the narrow-bore capillary GC(Ultra-2). The minimum detectable level of this analytical method was 0.019 - 0.035 ㎎/㎏. Sample throughput(extraction, open-column chromatography, and GC analysis) was decreased considerably (8h per sample).