Determination of Organochlorine Pesticide Residues in Sesame Seeds by GC-ECD

A method for the multiresidue analysis of 12 organochlorine pesticides in sesame seeds has been developed. The organochlorine residues in the seeds were first extracted by accelerated solvent extraction and the extract subjected to gel permeation chromatography to remove larger molecular weight materials such as proteins and waxes. The purified extract after gel permeation chromatography was analyzed by GC-ECD. Recoveries were higher than 75% for all compounds with relative standard deviations <20%. The limit of detection and limit of quantification were 1.6–3.3 and 5–10 ng g^?1, respectively.