A Gas Chromatography Method for Determination of Persistent Organic Pollutants in Sediment and the Research on the Removal of Contaminants

Sediment matrices containing a large amount of sulfocompound are complex. In this paper, the pre-treatment methods for analysis of organic pollutants in sediment are presented. The extraction technology uses the accelerated solvent extraction (ASE) technique and different methods were compared to eliminate sulfocompound. The results indicate that the additional 10 minute step by ultrasonic extraction with copper powder is necessary. Gel permeation chromatography (GPC) combined with solid phase extraction (SPE) was used to clean-up. This pre-treatment method meets the requirements of analysis by Gas Chromatography-Electron Capture Detector (GC-ECD). The method for the determination of persistent organic pollutants including 17 organochlorine pesticides and 8 polychlorinated biphenyls in sediment by gas chromatography was established. The average recoveries of the 25 compounds ranged from 68% to 131%. The relative standard deviation (RSD) for all the compounds was lower than 22.3%. The minimum detection limits (MDL) were between 0.1 and 0.51 μg/kg. This method can remove most of the contaminants in co-extractions, minimize the possibility of releasing false positive results and can be applied in analysis of different types of sediment.