多组分QSAR研究及其在废水毒物鉴别程序中的应用

本项目采用C18 Empore 盘模拟生物萃取，用奥斯摩蒸汽压分析仪测定多组分有机物总分子姆椒ǎ扑慊旌嫌谢锏腅mpore/水分配系数；以此研究多组分有机物的联合毒性效应与其结构性质之间的关系。本项目拟将多组分QSAR模型应用到废水有机毒物鉴别程序中，为废水毒物的鉴别提供依据。该项目研究将弥补单组分QSAR的不足，扩大多组分QSAR模型在实际环境中的应用价值。

The physicochemical properties of individual compounds have been investigated greatly. However, polluants almost exist in complex mixtures. In order to assess the potential hazard of mixtures, a novel parameter is urged to be proposed for mixtures. Since the fate of mixtures in environment is primarily affected by both the amount and the physicochemical properties of individual compounds. In 1995, Verhaar. et al. presented a physicochemical parameter, the partition coefficient for a mixture (KMD), which is related to the lipophilicity and the amount of the individual compounds in the mixture. According to the good linear relationship between C18-reverse-phase HPLC capacity factor k'i and Kow , Verhaar also extend C18-containing EmporeTM disks to simulate the equilibrium partioning of organic compounds and set up a experimental method for determining the partition coefficient (KSD) of single compounds. Although Verhaar and Van Loon mentioned the concep of KMD, they never studied the partitioning regularity of mixtures. In this project, firstly, C18 disk/water partition coefficients (lgKSD) for anilines, nitrobenzens, phenols, biphenylamines and benzoic acids in the different pH solutions were respectively determined. The results indicated the lgKSD values decreaded with pH increasing for the acid organic pollutants and increased with pH increasing for the basic compounds. Then C18 disk/water partition coefficients (lgKMD) for complex mixtures were determined. The results revealed the observed lgKMD values were different from calculated theoretical lgKMD values. We guess there are different accumulation processes for different compounds. .In order to set up a quantitative structure-activity model, combined toxicity tests for complex mixtures were firstly conducted. The results showed the combined toxic action is addictive not only for non-polar organic pollutants but also for these polar organic pollutants. The models of combined toxicity prediction were also set up for the complex mixtures of anilines, nitrobenzenes and biphenylamines. There were good relationships between the calculated KMD and the combined toxicity：A complex mixture for halegonated benzenes.Daphnia magna：pEC50M = 0.831lgKMD + 0.187.Photobacterium：pEC50M = 0.915lgKMD + 0.275 A complex mixture for biphenylamines.Daphnia magna：pEC50 = 0.621lgKMD + 0.496.A complex mixture for nitrobenzenes and anilines Daphnia magna：pEC50 = 1.334lgKMD - 2.017 This kind of study is helpful for assessing the combined toxicity behavior of such kinds of complex mixtures..In addition, based on the Toxicity Identification Evaluation (TIE) procedures of U.S.A. EPA, the primary toxic pollutants in effluents were identified. A QSAR model for mixtures was used to predict combined toxicity of effluents.