Determination of Organochlorines and Organophosphorus in Soil by Accelerated Solvent Extraction-Gas Chromatography

A large number of measurement work on organochlorine and organophosphorus pesticide residue in soil was carried out in China's environmental pollution survey evaluation and test project. The simultaneous measurements of a variety of organic pollutants were a new research hotspot. In this study, the pesticide residues of 9 kinds of organochlorine such as hexachlorobenzene and 13 kinds of organophosphorus such as dichlorvos were simultaneously measured by Gas Chromatography with n-hexane-acetone (volume ratio 1:1) for extracting agent, the accelerated solvent extraction and capillary column. The recoveries were from 79.1% to 107.7%, relative standard deviations were from 3.62% to 9.94% (n=7) and detection limits were from 0.02 to 0.45 μg/kg. This method simultaneously extracted the two kinds of pesticides and completely separated the various components, which extended the application field. Comparing with the traditional ultrasonic extraction and Soxhlet extraction method, extracting time of this method was reduced to 20 min and extraction solvent volume was down to 50 mL, which saved the analytical time and reduced the cost. Meanwhile, the precisions and recoveries met the requirements of the national environmental pollution survey and assessment.