Pollution Level And Ecological Security Assessment Of Phthalic Acid Esters Organic Pollutantsin The River Basins Of Main Districts Of Chongqing

Chongqing is China's fourth municipality City and special economic zone of rural and urban orchestrates, is an important port city and economic center, located in the center of the western region, also in the upper reaches of the Three Gorges in the upper reaches of the Yangtze River, Chongqing play a decisive role in western china. With the development of the plastics industry and phthalate plasticizers use, PAEs pollution is also widespread concerned more and more. So, it is great significance to the study of the distribution and ecological risk assessment of the environment of phthalate esters in Chongqing for providing basic data and future prevention and treatment.This study relying on the international Sino-German cooperation project of science and technology ministry(2007DFA90660) and science and technology tackling plan projects of Chongqing (CSTC,2006AA7003-1), taking the river basins of main districts of Chongqing as the study area, setting up 12 sampling points, respectively, collectting a water sample, pretreating and detecting and analysising at the June-November mid-month sampling period at each sampling point, analyzed the concentration distribution characteristics and environmental risk assessment of Phthalic Acid Esters by the quotient method in sampling period. The main theses of this research are as follows:①Selection and optimization of pretreatment of PAEs waters sampling.Pretreatment of PAEs waters sampling was set up. 1) the leaching of water samples; 2) Liquid - liquid extraction of water samples by dichloromethane; 3) concentration of water samples by rotary evaporation; 4) leaching purification of concentrated liquid by aluminum oxide column; 5) Re- concentration of eluant; 6) constant volume and analysis.②Selection and optimization of gas chromatography analysis condition of PAEs.Gas chromatography analysis condition of PAEs was selected and optimized: Agilent gas chromatograph 6890N, FID detector, chromatographic column: HP-5ms (30.0m×320μm×0.25μm), carrier gas: N2, flow: 0.8mL/min, air: flow: 400mL/min, hydrogen: flow: 40mL/min; injection mode: splitless, injection volume: 5μL; injection port temperature: 300℃; detector temperature: 300℃; temperature raising procedure of column boxes: 150℃(3min) 15℃/min 300℃(6min).③Temporal and spatial distribution characteristics of the river basins of main districts of Chongqing.This study analyzed temporal distribution characteristics of the river basins of main districts of Chongqing and reached the time-varying concentrations of the PAEs in the water sampling has nothing to do with the water level of Yangtze River. Also analyzed spatial distribution characteristics of the river basins of main districts of Chongqing, and come to a regular: from Chaotianmen to Jingkou of Jialing River, it is show that the concentrations of PAEs increase at first and lower finally along the Jialing River; from Yudong to Cuntan, also show that the concentrations of PAEs increase at first and lower finally along the YangZi River.④Pollution level of phthalate esters of the river basins of main districts of Chongqing.The main pollutants is DBP and DEHP, According to the DBP and DEHP of criterion value of Environmental Quality Standards of China for Surface Water (GB 3838-2002), DBP and DEHP limit of the standard are 3μg / L and 8μg / L 72 water samples sampling during the testing process, DBP concentration detected of 19 water samples comply with a standard only, DEHP concentration detected of 59 water samples comply with a standard; the over standard rate of DBP and DEHP were 73.61% and 18.06%, respectively.⑤Ecological risk assessment of the river basins of main districts of Chongqing.For the zebra fish embryo and algae during sampling at 12 sampling points, DMP has no ecological risk; some of the Q values of DEP lie in the range of low potential ecological risk; main pollutants DBP and DEHP did not have a direct ecological risk However, almost all of Q value lie in the potential range of low ecological risk, the relevant departments should attach importance to.