Distributions, Compositions, And Ecological Risk Assessment Of Typical Pollutants In Surface Sediment Of Xihe River, China

: Distributions and compositions of six phthalic acid esters (PAEs), eight 6 phenol compounds and seven heavy metals in riverbed sediments of the Xihe River in 7 Shenyang, China. The ecological risks of these typical pollutants were investigated 8 and evaluated based on the risk quotient (RQ) and potential ecological risk index 9 (PERI) methods. The concentrations of total ∑ 6 PAEs, ∑ 8 phenols and ∑ 7 heavy metals 10 in sediments varied from 92.83 to 293.66 μg/g dw, 8.87 to 83.73 μg/g dw and 0.46 to 11 419μg/g dw. The main pollutants in Xihe River sediments are DEHP, DIBP, phenol, 12 P - methylphenol and Cd. More than half target PAEs and phenol compounds in 13 sediment of the Xihe River exhibited medium or high ecological risk. Cd poses a very 14 high ecological risk to the Xihe River Basin. It is imperative to take some effective 15 measures to reduce the pollution of those contaminants.


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Due to Chinese rapid urbanization and industrialization, rivers are increasingly 20 threatened by all kinds of pollutants (Zhao et al., 2018). Riverbed sediments as 21 important sinks and sources for pollutants, the concentration of pollutants in it has a 22 great impact on aquatic organisms and the water environment, even influence the 23 entire ecosystem (Mi et al., 2019;Hu et al., 2020). can inhibit the central nervous system and have strong toxic, persistent and 34 bio-accumulative effects (Li et al., 2015). Due to the potential biological toxicity of 35 heavy metals, they may cause further adverse effects on human beings through 36 bioaccumulation (Xu et al., 2017). Because of potential risks to humans and the 37 environment of these typical pollutants, the comprehensive evaluations of ecological risks are required. 39 The Xihe River is 78 kilometers long and flows through the Tiexi District, the 40 most important industrial estate in Shenyang (Liu., 2016) . Due to the complete variety 41 and large number of factories around the basin, various types of wastewater are one of 42 the main sources of water for the Xihe River. A variety of pollutants in the basin such 43 as ammonia nitrogen, PCDD and dibenzofurans have been investigated and studied by 44 many people (Ke et al., 2018;Lin et al., 2013;Ke et al., 2019). It is still lack of 45 information on the pollution level of common PAEs, phenol compounds and heavy 46 metals in the river sediment, limited work has reported on the potential risk of these 47 pollutants in the Xihe River.

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In this study, we selected some representative sites as the study area to conduct a 49 risk assessment of heavy metals, PAEs and phenol compounds in Xihe River. The 50 purpose of this study is： (1) to study the distribution and compositions of heavy metals,

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PAEs，phenols and heavy metals in surface sediments of Xihe River; (2) To evaluate 52 the ecological risk of heavy metals, PAEs and phenol compounds in sediments.   The risk quotient (RQ) method was used to assess the potential environmental the predicted no effect concentration (PNEC), which is described as follows ; where MEC is the measured environmental concentration and PNEC is the 81 predicted no effect on centration. where PNECwater values were calculated from the 82 lowest acute toxicity data ,RHOsusp is the density of wet suspended matter, which is

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Quality assurance and quality control were assessed in duplicates, with method 104 blanks and standard reference materials. The content of pollutants was determined by 105 three replicates. No target pollutants were detected in the blank control groups.

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Quantitative analysis of all target compounds was corrected by data of blank test and

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The concentration of ∑6PAEs was shown in Table. 2. In the Xihe River, the mean The concentrations of phenol compounds (∑8phenols) in sediment from the 135 Xihe River were given in Table. 3. The concentration of ∑8phenols in sediments

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The concentration of ∑7heavy metals was shown in