Method for the Analysis of 22 Organochlorine Pesticides and 8 Polychlorinated Biphenyls in Soils and Sediments Using Gas Chromatography

In recent years, the main focus for improving detection methods for organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in groundwater, soils and sediments has focused mainly on pretreatment and analysis conditions. Comprehensive methods including sampling point design and sample collection were seldom studied. A new method was has been developed for the simultaneous determination of 22 OCPs and 8 PCBs in soils and sediments by Gas Chromatography coupled with electron capture detection. Method detection limits range from 0.09 ng/g to 0.48 ng/g, and the average recoveries are 58.7%-133.7%. This developed method seems to be a relatively integrated and widely applicable method, including sampling point design, sample collection, transportation, preservation, extraction, clean-up, concentration, determination, data analysis and reporting. Alternative technologies were recommended for extraction, clean-up and Gas Chromatographic condition, etc, which improves the flexibility of the method. The results show that the sampling point design for the samples collected from different depths should be considered on the basis of scouting samples and pre-existing data since the representativeness of samples comprehensively depends on selecting procedure, sampling point design, sample collection and preparation. A flexible Gas Chromatographic condition can be used for those samples with rare target compounds, and a corresponding Gas Chromatographic condition can be used further if special target compounds need to be separated. Sequence of the samples should not be oversimplified in order to save cost.