| The determination of organic contaminants in the environment is one of the hot subjects in the environmental research field now. Semi-permeable membrane device (SPMD) is the advanced measure that effectively combines chemical analysis with biological monitoring. In this study, we use SPMD to sample organochlorine pesticides (OCPs) in groundwater and analyze them by gas chromatography (GC).OCPs are a broad spectrum, high performance, low-cost insecticide, and a kind of artificial synthetic toxic organic compound, which threatens the environment seriously. They appear in the blacklist of priority control pollutants announced by the world. OCPs can be released to air, water and soil and have serious effect on environment because of their toxicity.The concentration of organochlorine pollutants in drinking water and waste water is very low .It is difficult to determinate directly .So it is necessary and imperious to develop a new method to sample organic contaminants continuously in the exposed medium in a certain range of time and to concentrate organic contaminants to a detected degree. Generally, we calculate the concentration of persistent organic pollutants (POPs), which is very low in the water by the concentration of organism or sediment under equilibrium condition. There are some obvious disadvantages in biologic sampling: costing so much, the kind and gender of biology, and the individual difference. Furthermore, the processing procedure of biologic samples is complex. Similar to biologic sampling, sediment analysis is affected by sampling sites and character of sediment. Passive sampling technology is similar to collecting contaminants by biology. Triolein-SPMD is the emphases of nowadays research and development in every kind of passive sampling technology.BHC, DDT, heptachlor, hexachlorobenzene, heptachlor epoxide, dieldrin, aldrin, endrin are the target compounds in this study. Combine the conventional pretreatment method with SPMD by studying pretreatment method for groundwater samples and establish a qualitative, quantitative method and quality control, quality assurance system.A viable and credible analytical method should be established applying GC-ECD. In this study, we confirmed optimize condition of temperature programming by attempting some different temperature programming and confirmed other analytical parameters according to correlative literatures. We proved precision and accuracy of analysis result by quality control and quality assurance. The result showed that the determination method meet the requirement of chromatographic analysis. And it can be used to test OCPs in the surface water and ground water. The detection limits of OCPs in this thesis are lower than that are listed in the EPA standard method except for endrin.The uptake rates (Rs) values of OCPs are independent of the concentrations of contaminants and increase with compound hydrophobicity. They can be obtained by simulating experiment in the lab. To reflect the values of the uptake rates in different medium and concentration, we conducted three samples: tap water medium spiked low concentration OCPs, tap water spiked with high concentration OCPs, and pure water spiked with high concentration OCPs respectively. In the three samples, the collection for OCPs by SPMD presented linear relationship along with time and we obtained three groups of Rs values by experiment. In this study, we used Rs values which were obtained by the experiment of tap water with low concentration OCPs to calculate the concentration of water samples because the concentration of OCPs is not very high in the surface water and ground water.After the establishment of analytical method that is viable and credible and the obtainment of a group of Rs values by lab simulate experiment, we verify the method in Liangshui River in Beijing. We compared the in-suit large volume sampling with SPMD at the same time. The determination results show that the concentration range of the target compounds is from 0.6 to 7.0 ng /L in the in-suit large...
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