| The synthetic organic compounds, especially the groups of polychlorinated organic compounds, commenced in the middle of the nineteenth century for agricultural and industrial purposes, have caused and are still causing undesirable effect. Their omnipresent in the environment, their stability, their gross misusage, their severe toxicity, and propagators of chemical sensitivity make the discussion about their properties, their residues in the environment and their effects to wildlife and human extremely important. Thus it is very important to evaluate the pollution levels and characters in the environment for the pollution prevention to these poisonous chemical compounds.According to US EPA method, Using traditional soxhlet extraction and gas-chromatography/electron-capture detection (GC/ECD), this work built up a series of methods of monitoring trace pollutants which were adapted for 7 PCBs and 13 OCPs. This work analyzed the pollution levels of PCBs OCPs in soils and TSP of Qingdao area.60 topsoil samples were collected from arable land, roadside land and vegetable land. The result indicated that the value of PCBs in soils were in a range of 3.06—14.88ng / g, the average value was 8.04ng / g. The residues of OCPs in soils were in a range of 5.07—87.77ng / g, the average value of OCPs was 32.58ng / g. ΣHCHs and ΣDDTs took over 12.31 % and 81.37% of the total OCPs, respectively. DDT and its metabolites were main pollutants in soils of Qingdao area.Compared to the reference data, the pollution burden of PCBs and OCPs in soils of Qingdao area was lower than those in other areas in China. HCHs and DDTs in soils were mainly the residues of past. The main sources of PCBs were the transportation and deposition of the atmosphere. There were no new sources of HCHs, but few of DDTs or other pesticides adulterated DDT were using in Qingdao area.TSP samples were collected in Qingdao University from January to December 2005. The result indicated that the value of total chlorinated organic pollutants in TSP ranged from 28.64 to 53.59 pg/m~3, the average value was 41.40pg/m~3, and the mainly pollutants were DDTs, PCBs, HCB, HCHs and Aldrin, which took over 40.0%,17.6%, 17.2%, 13.9%#1 7.5% of the total chlorinated organic pollutants, respectively. It was found that the concentrations of chlorinated organic pollutants tended to be in the order of winter> spring> summer> autumn.It was found that the values of PCBs of TSP were in a range of 5.22 and 8.58pg/m3, the average value was 7.32pg/m3.The seasonal variations of PCBs were not obvious. There was a tendency for the concentration of PCB homologs in the TSP to decrease with increasing number of Cl.The values of OCPs of TSP were in a range of 20.58 and 46.8pg/m3, the average value was 34.07pg/m3. The mainly contents were DDT and its metabolites, HCB, HCHs and Aldrin, which took over 48.6%, 20.8%, 16.9%*P9.2% of the total OCPs, respectively.Compared to the reference data, the pollution burden of PCBs in TSP of Qingdao urban area was the same magnitude to foreign countries, but it was higher a little than the reginal background of polychlorinated biphenyl in the Pearl River Delta atmosphere, Moreover it was much lower than those pollution areas in China. The pollution burden of OCPs in TSP was moderate level, but it was much higher than that of foreign country, obviously.By analyzing and research the data, it could be concluded that the main sources of PCBs were city waste combustion and vehicle let. Otherwise, the industries of chemical, petroleum and paper making in Qingdao were also important sources. The OCPs were mainly come from the atmosphere transportation and volatilization of the residues in soils and waters in study area. At the same time, there were new souce of DDTs. DDTs or other pesticides adulterated DDT were using in Qingdao rural area. The sequence let of chemical and petroleum industries and waste combustion were mainly sources of HCB.
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