Study On The Water Quality Characterization And Screening Of Toxic Organic Pollutants Of Fu River In Baoding

The water quality of Baiyangdian Lake has attracted broad public attention in recent years.Fu River,a tributary of Baiyangdian Lake,constantly receives municipal sewage and industrial wastewater.There are many toxic refractory pollutants in the Fu River water,thereby posing a threat to the ecological environment of Baiyangdian area.Therefore,it is essential to investigate the water quality characterization of Fu River and screen for toxic organic pollutants in water body,so as to identify the key toxic pollutants which can provide reference for the follow-up water environmental governance.In this study,six representative sampling sites of Fu River in Baoding were selected as the research objects,water samples were collected in different seasons.Through physicochemical indicators analysis and water quality assessment,we studied the water pollution status of Fu River and identify the key pollution indicators which laid the foundation for the study of water biotoxicity.The acute toxicity of Fu River water was evaluated by combining the Vibrio Qinghaiensis SP.Q67 toxicity test with zebrafish toxicity test,and then,based on physicochemical indicators,analyzed toxic factors systematically and laid the foundation for screening of toxic organic pollutants.The representative toxic pollutants in Fu River were screened out by component separation,biological toxicity test,gas chromatography-mass spectrometry（GC-MS）identification analysis and comprehensive evaluation method.The main conclusions of this study are as follows:（1）The results of physic-chemical analysis and water quality assessment show that TN,COD and NH₃-N are the main excessive pollutants and restrictive factors of water quality level in Fu River and the metal pollution level is low.Water quality in July is the worst,and better water quality in October than in other months.When TN participates in the assessment,all sampling sites belong to inferior V,which failed to meet the requirements of III or IV function planning area.The annual comprehensive pollution index and Nemerow index of each sampling site in Fu River ranged from 0.96 to 1.48 and 3.51 to 4.89,respectively.The comprehensive water quality of Baiyangdian Bridge was the worst.（2）The water of Fu River had certain acute toxic effects on Vibrio Qinghaiensis SP.Q67as well as zebrafish and the toxicity level was low.The statistical analysis on toxicity indices and physicochemical indicators,COD,NH₃-N,Zn,and Cu were the pollution factors that gave rise to the acute toxicity of Fu River water and thus should be put under special control.Furthermore,the tests performed on Vibrio Qinghaiensis SP.Q67 are more suitable for evaluating the acute toxicity of Fu River water due to high sensitivity and efficiency.（3）Through the screening system which established by sample component separation,biological toxicity test and GC-MS analysis,42 kinds of organic pollutants were identified as the primary list of toxic organic pollutants.Through the comprehensive evaluation method,The organic pollutants in the primary list are ranked and identified 14 kinds of toxic typical organic pollutants in Fu River water,such as dibutyl phthalate,diethyl phthalate,heptadecane,anthracene and naphthalene etc.