| Polycyclic aromatic hydrocarbons (PAHs) are well know persistent organic pollutants (POPs) and widely investigated by researchers around the world due to their notable carcinogenic, mutagenecity properties and persistency. The basic and key element of all these research work is their physical-chemical properties. So a set of recommended physical-chemical properties, with accurate and themodynamic consistency, is necessary. The thesis began with this topic and the following works were carried out as described below.A complete set of thermodynamically consistent property data (vapor pressure, aqueous solubility, octanol solubility, octanol-water partition coefficient, octanol-air partition coefficient, and air-water partition coefficient) for sixteen PAHs (naphthalene, acenaphthylene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, chrysene, benzo[a]anthracene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, indeno[1,2,3-c,d]pyrene, dibenzo(a,h)anthracene and benzo[g,h,i]perylene) was derived from measured data reported in the literature. First, literature derived values (LDVs) at 25°C for each property of 16 PAHs were obtained by averaging, regressing and extrapolating after changed to standard units and liquid state. Then the LDVs were adjusted to conform the thermodynamic relationships by a least square adjustment procedure. The influence of the mutual solubility of octanol and water on phase partitioning is taken into account in the adjustment of the KOW. Compared to other semi-volatile organic compounds, the LDVs for the PAHs display a high degree of thermodynamic consistency and require only minor adjustments. The LDVs and the adjusted values for all properties show highly linear regressions with molecular mass (R2 > 0.9). The final adjusted values (FAVs) were recommended for further research work related to PAHs.In order to compare and assess the accuracy of result calculated by models, four popular quantitative structure-property relationship (QSPR) models were employed: SPARC online, EPIWIN, COSMOtherm and pp-LFER. There has none relative report about the accuracy of each model for predicting the properties of PAHs before though it is essential for further use. We defined the FAVs as criteria to judge the accurate of results from models. Discrepancy was found for every model despite of their precision and thermo-consistency. The comparison showed that the experimental data, adjustment procedure and thermodynamic consistency are all valuable factors in evaluating a QSPR method. The results showed that good precision and thermo-consistency cannot represent the accuracy of a model. The accuracy of xperimental data and result from model can test each other.In order to verify the influence of properties on behavior and fate of 16 PAHs, environmental sample and a fugacity model were employed. The environmental fate of 16 PAHs were investigated by selecting air, soil and leaves samples in several typical function districts in Shanghai and in Level III model. The results showed that the average concentration of 16 PAHs in PM10 were 132±83 ng/m3 in two years. Samples from Cocking Chemical Plant had the highest PM10 concentration than others while samples from Dianshan lake are far lower than that from the industrial area. And 2,3,4-ring PAHs took predominant level in PM10 while 2,6-ring PAHs were seldom detected. In spit of the environmental factors, physical-chemical properties of compounds are the key point in determining their environmental fate. PAHs are obvious influenced by the change of temperature. Usually the higher PAHs concentrations in PM10 appeared in autumn to winter while the lower ones in spring to summer. This character also had intimate relationship with local weather as while as their physical chemical properties. And risk assessment of PM10 showed that BaPE were much higher in industrial district than rural area. Results from soil samples also showed that 16 PAHs in soil from industrial area (Cocking Chemical Plant,Chloro-alkaline Chemical Plant,Thermo Power Plant were 3258 ng/g, 1873 ng/g and 994 ng/g respectively) were higher than that from others, and the sample from Dianshan lake was still the lowest one (10.7 ng/g). At the same time, PAHs detected in winter were always higher than in summer. And the 2,3,4-ring PAHs took prevalent level in winter samples while 3,4,5-ring PAHs in summer samples. Six-ring PAHs had only less detected in soil samples. This distribution pattern was mainly determined by the vapor pressure of PAHs except for environmental factors.Diagnositic ratio analysis showed that PAHs in PM10 mainly came from the industrial waste gas, followed by traffic discharge and dustfall of road. Diagnositic ratio result for soil samples illustrated that the coal burning and traffic were their mainly source. Analysis of PM10 sampled just aroud the funnel of CCP had almost identical results as the reported data in literatures.Leaf samples from three evergreen species (southern magnolia, camphor tree, boxtree) and one deciduous species (phoenix tree) in Shanghai were sampled during 2005 to 2006. The results showed that there has big difference in accumulating capacity and tendency among these species. For the phoenix tree, the accumulation of PAHs increased with the growth of leaves till the leaves mature. PAHs in evergreen trees were variable with the change of temperature. Their accumulating capacities and tendencies were different among three evergreen species. Leaves from phoenix tree had higher capacity in intercepting and accumulating PAHs from air than evergreen species due to the character of leaf and properties of PAHs. Two passive sampler devices, SPMD and XAD, were employed to investigate their accumulating pattern and tendency of PAHs. The results showed that concentration of total 16 PAHs in XAD were 2 to 8 times than that in SPMD. This should be attributed to the character of SPMD and XAD and properties of PAHs.A fugacity model– Level III model, invented by Prof. D. Mackay from Trent University, was employed to illustrate the fate of PAHs in environment and the function of their physical-chemical properties (FAVs). The results showed that the PAHs tended to be accumulated fast in organic phase with the increasing of molecular mass and benzene rings while decreased in gas phase. And the exchange between phases also increased or decreased regularly. Results from Level III model were lower than the experimental results in Shanghai. This discrepancy decreased after adjusted two input parameters of Beyer Environment. The comparison verified that Level III model can be used in predicating the fate of PAHs in some certain typical area. It can also be used in predicting the fate and tendency in environment for compounds with similar structure and molecular mass without related property data.
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