| Persistent Organic Pollutants(POPs)are chemical substances that persist in the environment, bioaccumulate through the food web, and pose a risk of causing adverse effects to human health and the environment. Their persistence in various media facilitates their transport over long distances to remote regions where they have never been used or produced, posing threats to the environment of the whole globe. Consequently, the studies on the fate of POPs in the environment have been the focus of a number of environment field studies. By using isotope dilution/high resolution gas chromatography (HRGC) / high resolution mass spectrum (HRMS) and gas chromatography (GC)/low resolution mass spectrum (LRMS) method, the concentrations, PCDD/Fs, PCBs and OCPs from typical industrial cities and the typical polluted areas were studied. This thesis is mainly concerned with the following aspects:(1) In this study, the levels of PCDD/PCDFs and dl-PCBs in sediments from the rivers of typical thermal industrial city Tangshan and chemical industrial base Tianjin, Tanggu were investigated. The PCDD/Fs concentrations in sediments from Douhe river ranged from 4.14 to 123.7 pg/g, the TEQ concentrations of PCDD/Fs ranged from 0.29~3.55 pg WHO-TEQ/g. Meanwhile, the concentration of PCDD/Fs in sediments from the main rivers of Tanggu ranged as high as 40603.5~1180923.0 pg/g, the TEQ concentration reached 136.0~3272.3 pg WHO-TEQ/g. As to dl-PCBs, the concentration of the sediments from Tangshan and Tanggu were in range of 6.73~173.6 pg/g and 1636.0~5007.0 pg/g respectively, the TEQ concentrations ranged 0.01~0.16 pg WHO-TEQ/g and 2.44~47.28 pg WHO-TEQ/g. Our research demonstrated that Tianjin and Tanggu were heavily polluted by PCDD/Fs and dl-PCBs. Nevertheless, the result that the levels of PCDD/Fs and PCBs in rivers of Tangshan area was lower showed that the chemical industrial contamination in Tangshan was not serious. Moreover, through the PCDD/Fs homologue profiles analysis, the PCDD/Fs pollution in Tanggu area was likely to come from the previous production of PCP and PCP-Na.(2) Occurrence and distribution of organochlorine pesticides (OCPs) in surface sediments of the Ya-Er Lake: HCHs, DDTs and HCB were analyzed by gas chromatograph-mass spectrometery (GC-MS). The concentrations of HCHs, DDTs and HCB were 0.85~19.8, 2.2~34.5 and 0.13~8.8 ng·g-1 respectively. The levels of OCPs in Ya-Er Lake had been greatly decreased compared with previous data in 1990s. Concentrations of OCPs in Ya-Er Lake were at the same magnitude compared with those of surface sediments collected from other polluted lakes in China. The distribution characters of HCHs and DDTs indicated that the OCPs mainly came from early residues. The risk of OCPs in surface sediments is relatively low when comparing with the ERL and ERM value of risk evaluation. The results indicate that there is no serious threat to the ecological environment.(3) In addition to the study of the various types of industrial areas, we also investigated the distribution characteristics and the status of the PCDD/Fs dl-PCBs and OCPs in the sediments of Haihe River Basin ( except Tanggu reach) which is the largest river system in Northern China. The PCDD/Fs and PCBs concentrations in sediments from Haihe River Basin ranged from 11.68~115.1 pg/g and 18.7~759.0 pg/g, respectively; The TEQ concentrations of PCDD/Fs and PCBs in sediments from Haihe River Basin ranged from 0.29~3.05 pg WHO-TEQ/g and 0.030~1.36 pg WHO-TEQ/g, respectively. The concentrations of HCHs, DDTs and HCB were 0.13~1.57 ng/g, 0.45~2.48 ng/g and 0.37~4.18 ng/g, respectively. Compared with the pollution source above, the levels of PCDD/Fs and PCBs were almost with those of Tangshan but quite lower than those of Tianjin Tanggu area and the levels of OCPs was greatly lower than that of Ya-er Lake. Additionally, the comparison with other regions illustrated that the contamination level of POPs in Haihe River Basin was low, but due to the bioaccumulation, the pollution should not be ignored.
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