Concentration Distribution And Source Analysis Of Phthalates And Perfluorinated Compounds In The Chongqing Section Of The Yangtze Rive

Phthalates esters(PAEs)and perfluorinated compounds(PFCs)are typical Emerging organic contaminants and they have attracted significant social concerns due to their persistence,bioaccumulation,potential toxicity and long-distance transport.The Chongqing section of the Yangtze River is a major component of the Three Gorges Reservoir Region.It is also the main water source of industrial and agricultural production,as well as the domestic water supply in Chongqing.Therefore,the water quality has direct impact on the production and living conditions,and the health issues of residents around and downstream.In order to understand the distribution characteristics and risk levels of phthalate esters and perfluorinated compounds in the Chongqing section of the Yangtze River Basin and the emission characteristics of phthalates and perfluorinated compounds from typical pollution sources along the Yangtze River coastal.In this study,the mainstream of the Yangtze River and its two tributaries(Jialing River and Wujiang River)and typical pollution discharge sources along the coastal were selected as research objects in Chongqing.Based on the establishment of two types of pollutant analysis methods,the residual levels,pollution characteristics and ecological risks in the river,as well as emission characteristics of typical pollution sources are discussed,and the following conclusions are drawn:(1)The concentrations of PAEs detected in the water and sediments of Chongqing section of the Yangtze River are 6.18～81.8 μg/L and 2.24～12.26 μg/g,respectively and the main pollutants are DBP and DEHP.The concentrations of PAEs in the middle reaches of Yangtze river was significantly higher than those in the upper and lower reaches,which is related to the distribution of coastal industrial enterprises.No obviously regularity was found in the distribution of PAEs in sediments,which was relatively less affected by industrial wastewater discharge.(2)The concentrations of PFCs detected in the water and sediments of Chongqing section of the Yangtze River are 1.54～61.94 ng/L and 1.31～60.17 ng/g,respectively.The short-chain substances have a dominate position in water and the long-chain substances have a position dominate in sediments.The spatial distribution of PFCs generally showed a trend of decrease along with the water flow,and No obviously regularity was found in the distribution of PAEs in sediments,indicating that the human activities impact that the PFCs pollution level.(3)The ecological risk assessment results of PAEs and PFCs in the Chong Qing section of the Yangtze River show that DBP is the main PAEs risk pollutant in the water,and there is a high probability of potential ecological risk of DEHP in sediments;The concentration level of PFCs has not reached a level that is dangerous to the ecological environment in the water and sediments.(4)The concentration ranges of PAEs and PFCs in industrial enterprises,domestic sewage treatment plants and garbage treatment plants are 1.11～21.71 μg/L and 0.021～1031.74 μg/L,1.37～6.42 μg/L and 0.043～21.31 μg/L,1.72～11.74 μg/L and 0.051～417.49μg/L,respectively;the main monomers detected in the three pollution sources are the same.In general,the detection concentration of PAEs is higher in waste treatment plants,and the detection concentration of PFCs is higher in industrial enterprises.PAEs have a dominate position in the majority of pollution sources,which is related to the nature of the industry,production processes,and the quality of the water being treated.This study explores the content characteristics,spatial distribution,source analysis and ecological risk assessments of PAEs and PFCs in Chongqing Section of the Yangtze River.It also understands the emission characteristics of PAEs and PFCs in typical local pollution sources.The results of this study supplement data of PAEs and PFCs from environmental investigations in Chongqing Section of the Yangtze River,and provide basic data and related information for the protection and improvement of the ecological environment of Chongqing.