Abstract:

The Liao River basin and surrounding has many developed tributaries with dense industries and the regional pollution problem of PFASs has attracted widespread attention. In this study, the concentration and composition of PFASs in Xi River in Fuxin, Daling River, Liao River, Liao River estuary and Hun River were analyzed by collecting the concentration data of PFASs reported in recent years, and the quotient value method and safety threshold method were applied to carry out ecological risk assessment. The pollution level of PFASs in Xi River-Daling River was significantly higher than that in other Rivers, and PFOA and PFBS were the main pollutants. The composition and concentration of PFASs in the Xi River and Daling River vary seasonally, and frequent rainwater and surface runoff in summer will bring PFASs from the air and soil into the water body to worsen contaminative degree. The pollutions of PFBS, PFOA and PFOS are the main compounds in the water body of Liao River estuary. In addition to the distribution of local industry, PFASs in the upper water bodies also have a certain contribution to the estuary. The pollution degree of waterbody in Hun River is low relative to other Rivers. The intensive fluorine chemical industry in Fuxin is an important source of PFASs in the water body of surrounding Rivers, but the concentrations of PFOS and PFOA show a decreasing trend, which is mainly related to the widely use of short chain substitutes. The results of quotient value method shows that when HQ=0.3 is taken as the benchmark of potential risk assessment for water body, Xi River has a higher proportion of risk water body (46.15%), followed by Daling River (12.01%). The result of quotient value method is the same with safety threshold method. The ECD curve and the SSD curve has a small area of overlap, indicating that total risk of all studied Rivers and areas is relatively low without the serious ecological risk.

Key words: Liao River basin, perfluorinated compounds, perfluorooctane sulfonate, risk assessment, HQ, MOS₁₀

摘要：

辽河流域及周边拥有众多发达的水系且分布着密集的农业与工业,不同河流水体中全氟化合物（Perfluorinated compounds,PFASs）的污染问题已经引起人们的广泛关注。该研究通过收集近年来相关报道中PFASs的浓度数据,比较分析了包括阜新细河、大凌河、辽河干流、辽河入海口以及浑河等不同区域水体中PFASs的浓度与组成,并应用熵值法与安全阈值法进行生态风险评价。细河-大凌河水体中PFASs的污染水平最严重,以全氟辛烷磺酸盐（Perfluorooctanoate,PFOA）与全氟丁烷磺酸（Perfluorobutane sulfonate,PFBS）污染为主。此外,水体中PFASs的组成与浓度具有季节性变化的趋势且夏季频繁的雨水以及地表径流会将空气和土壤中的PFASs带入水体中,加大水体中PFASs的浓度。辽河入海口附近水体以PFBS、PFOA与全氟辛烷磺酸（Perfluorooctane sulfonate,PFOS）为主,除与当地的工业分布有关外,上游水体中的PFASs也具有一定的贡献作用。浑河水体相对其他水体而言,污染程度相对较低。阜新密集的氟化工产业是周边河流水体中PFASs的重要来源,而水体中PFOS与PFOA的浓度水平呈现下降的趋势,这主要与短链替代品的使用有关。熵值法结果显示,以HQ=0.3作为潜在风险水体基准评估时发现,细河具有较高比例的风险水体（46.15%）,其次是大凌河水体（12.01%）。安全阈值法与熵值法结果基本一致,ECD曲线与SSD曲线具有较小面积的重叠,说明所有研究河流与区域的总体风险值偏低,并不具有严重的生态风险。但随着污染源的排放,水体中的PFOS对水生生物的危害性会逐渐增强甚至干扰当地水生生物的生长发育。

关键词: 辽河流域, 全氟化合物, PFOS, 风险评价, HQ, MOS₁₀