| Polychlorinated biphenyls (PCBs) are typical Persistent organic Pollutants. The pollution of PCBs presents regional and multi-edium charaeteristies, which poses latent threats to human health and the ecological security. PCBs have been used in China area and the surrounding areas for a long time, especially in 70s and 80s. At present, although the business has ceased making PCBs, but in the world, there are lots of PCBs in some the electrical system and ecological system. As PCBs are quite stable and is not easy to break down, in the future many years, many of PCBs will be long existed in the environment. But the research about PCBs pollution in environmental is little. Therefore, the research about components and source of PCBs in the environmental media in jinan area have important significance to evaluate PCBs effect to jinan areas of ecological environment safe and explore management methods and develop the environmental policies.In 209 polychlorinated biphenyl ongeners, the coplanar PCBs which has mono-ortho-substituted or no-ortho-substituted chlorine atoms were named Dioxin-Like Polychlorinated biphenyls (DL-PCBs). They include 12 types and have the highest toxicity.We collected the 10 samples of road dust from the main cross road (freeway, primary road, branch) in Jinan, and collected 12 soil samples from zhangqiu, jiyang, shanghe, changqing, licheng, and huaiyin areas. Using the method of gas chromatography with electron capture detection (GC-ECD), the residues of 12 types of Dioxin-Like Poly-chlorinated biphenyls (DL-PCBs) with higher toxicity were analyzed. The residual concentration and distribution of DL-PCBs were given in details. The results indicated that:(1) The detection and analysis results indicated that except PCB189, the others 11 DL-PCBs were detected in all samples.The average road dust concentration of DL-PCBs in Jinan area was 5.069 ng/g dry weight.∑DL-PCBs are distribution in 0.20～22.84 ng/g dry weight. Compared with other areas, the average concentration of∑PCBs in the area atmosphere was in the middle level. The detectable amount is ortho-position substituted PCB77. in order PCB123>PCB167>PCB156>PCB157>PCB118, The detection ratio of PCB81 is the highest. By the TEQ calculating, the total TEQ of 12 species of DL-PCBs is 0.050～117.100 pg/g dry weight.(2) The detection and analysis results of soil samples indicated that except PCB169 and PCB189, the others 10 DL-PCBs were detected in all samples. The average soil concentration of DL-PCBs in Jinan area was O.lOng/g dry weight.L-PCBs are distribution in 0.02-0.63 ng/g dry wight. The highest concentration was in Changqing Guide town. DL-PCBs was detected in Zhangqi, Jinyang, Pingyin, Changqing, Licheng and Huaiyin area.The three high species of DL-PCBs is PCB114>PCB77> PCB167. The total TEQ of 12 species DL-PCBs is 0.0020～0.111 pg/g dry weight. (3) In addiation, from the inspection results of atropisomeric PCBs which have hand-type structure, we find that:except PCB174, other 3 species of atropisomeric PCBs and their hand-type structures was detected. The average concentration was 0.49 ng/g, and the total concentration was distribution in 0.192～1.253 ng/g dry weight. The highest content is PCB95-2, and then are PCB132-2, PCB149-1. As some hand-type structure isomers of atropisomeric PCBs in the samples was different, the content of isomers in soil are not inequality.(4) By analyzing the characteristics of the relative distributions of DL-PCBs and the characteristies of the relative distributions of PCBs with different Cl atom, it comes to the conclusion that the type of PCBs Pollution was Aroelor 1242, and it was known that the source of PCBs was the Insulating oil in the Power Equipments that had the similar composition with Aroclor 1242. A large number of the Power Equipments ever be used, and may be the main source of PCBs contamination in this area.(5) In this paper, we apply the method of quantum chemistry to research the Reaction mechanism of Dicofol and OH free radical, in order to find practicable Reaction Pathway and point. The analytic results of frontier electron density and bond dissociation energy show that we can use these two methods to predict the initiation sites of initiation sites by OH induced, and the results are agreed with the experimental results. At the same time, we find two reaction pathways between Dicofol and OH free radical. The Rotational Barrier for OH substitude of CCl3 is lower. The product DCBP is the major determination product.
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