海洋环境中全氟化合物新型替代品—全氟/多氟醚类物质的赋存、来源和生物富集/放大效应研究

Nowdays part of PFASs has already been or will be phased out within and outside of China and fluorinated alternatives are being used in increasing quantities which result in their emerging into the environment. It was reported that one of the alternatives for PFOS (6:2 Cl-polyfluoroalkyl ether sulfonate, with the trade name of F-53B), which was firstly reported in 2013, was detected in Greenland marine mammals while China is the only country with a documented usage of this compound. Another novel alternative for PFOA (HFPO-TA) was firstly reported in 2017. However, to the best of our knowledge, fundamental research on environmental occurrence, emissions and behaviors of these novel fluorinated alternatives, especially in marine environment, are poor. In this study, two classes of alternatives (PFAESs and HFPOs) are selected. Their levels and compositions in rivers and drain outlets which are directly into the sea, surface seawater and marine species from the Bohai Sea of China were systematically measured. These measurements, together with the spatial and temporal distribution of the alternatives will facilitate an evaluation of emission estimates and the main emission sources of the target pollutants, which is a prerequisite for determining the impact of Chinese emissions on global novel fluorinated alternatives transport and fate. Atmospheric deposition is also included to vestigate its contribution to the novel fluorinated alternatives in the sea and also their total emissions into the environment. Moreover, bioaccumation factors of the alternatives in marine species and their biomagnification potential in the marine food web, as well as their influencing factors will be quantitatively examined. These results will be helpful for the ecological risk assement and pollution control of this class of pollutants.

为替代当前受控的传统全氟化合物（PFASs），PFASs新型替代品大量进入环境且未来有急剧增长趋势，但环境中此类化合物的污染、来源及其环境行为等基础研究目前十分有限。为此，本项目选择两类PFASs新型替代品（多氟烷基醚类磺酸化合物，PFAESs；全氟醚类羧酸物质，HFPOs），以渤海为研究区域，定量研究各入海污染源（入海河流、排污口和大气干/湿沉降）中目标化合物的浓度水平、组成状况和时空分布特征，估算各污染源的入海通量，并在此基础上评估海洋环境中此类新型污染物的主要来源。同时，考察海水和海洋生物体中此类物质的赋存特征，探讨污染源和海水污染的对应关系，并基于相关浓度水平的分析数据，定量研究PFASs新型替代品在海洋生物体上的富集能力及其在海洋食物链间的放大效应，进一步探讨其影响因素和影响规律，为PFASs新型替代品的生态风险评估和污染控制等提供基础数据和理论依据。

本项目重点开展我国辽东湾入海河流和排污口中传统和新型全氟化合物(PFASs)的赋存和输入通量、渤海油气区周边海域PFASs的赋存特征与来源研究，以及浒苔黑炭对PFASs的吸附作用等方面的系统研究。.辽东湾上游存在我国较大的氟工业园区，通过辽东湾沿岸河流和排污口的93个水样分析结果认为，河水样品总PFASs的含量范围为7.75 ng/L至750 ng/L；城市污水和工业废水样品的含量范围分别为13.9至360 ng/L和30.6至73.1 ng/L。PFOA是辽东湾沿岸水体中最主要的PFASs。对于新型PFAS替代品，6:2 Cl-PFESA和HFPO-DA也常被检出。与排污口相比，河流输入量占总输入量的98.6%，河流输入是辽东湾PFAS污染的主要来源。.渤海油气区周边海水中调查结果表明，总PFASs浓度范围为9.33~113 ng/L。与中国其他海域相比，渤海油田区周边海水中总PFASs含量较高。传统PFASs中，PFOA是大部分样品中的主要PFASs。新型替代品中，HFPO-DA的浓度相对较高，浓度中位数为1.82 ng/L，而在所有样品中6:2 Cl-PFESA均未检出。从区域分布来看，总PFASs浓度较高的油田位于渤海西部。总PFASs含量与离岸距离等影响因素相关性分析表明，陆源是渤海油气区中PFASs污染的主要来源。.浒苔生物炭对PFASs吸附研究结果表明，经过酸化改性后的生物炭比原样生物炭对PFOS、PFOA有更强的吸附作用。溶液pH值和离子强度对于生物炭的吸附具有明显的影响，因此对影响作用进行了定量研究。相关的定量数据研究结果对于未来处理废水中PFASs并充分利用生物资源等具有重要的指导作用。