| As a kind of persistent organic pollutants (POPs), polycyclic aromatic hydrocarbons (PAHs) can cause cancer, monstrosity, and mutation. Being one of the important limnetic reservoirs to Tianjin City, Haihe River has been severely polluted. For the first time, the distribution, Sources of pollution, and sorption-desorption process of PAHs in sediments of Haihe River were studied in this paper.Sediments were collected from 13 random sites along Haihe River and PAHs were analyzed by a set of analysis programs mainly including freeze drying, accelerated solvent extraction, silica gel cleanup and GC-MS quantitation. The result showed that in this area the total concentrations of PAHs ranged from 774.81 to 255371.91 ng/g dw. At the same time for the sake of public health, a health risk-based assessment is developed, which indicated PAHs in Haihe River could severely damaged the public health. In addition, the distribution of PAHs in this area was analyzed and the result showed that the levels of PAHs in the urban and industrial regions were far beyond the values in other regions in Haihe River.Moreover, in this study some molecular ratios such as phenanthrene/anthracene (Ph/An), fluoranthene/pyrene(Fla/Py), Chrysene/Benz[a]anthracene(Chr/BaA) and low- molecular-weight PAH/high-molecular-weight PAH(LPAH/HPAH) were used to find out the possible sources of pollution, which indicated a mixed pattern of parolytic and petrogenic inputs of PAHs in sediments in Haihe River.Based on the microprocessed of sorption-desorption equilibriums, the factor temperature in the dynamic desorption was studied and a first-order desorption kinetics model was established. In this model PAHs had the larger obvious desorption quantity when the temperature became higher. Besides, the predicted results of this model and its experimental values were close to each other. This model can display the relation between temperature and the sorption-desorption process in high quality.
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