拉萨河全氟化合物的时空分布特征研究

对拉萨河27个采样点、拉萨污水处理厂分别在丰水期和枯水期进行水样的采集，并用双三元二维液相色谱-串联质谱法（DGLC-MS/MS）首次对水样中的17种全氟化合物（PFASs）进行检测分析，结果表明，PFASs在拉萨普遍存在，拉萨河表层水中平均Σ₁₃ PFASs浓度为322pg/L，范围从60到1724pg/L.拉萨河PFASs的浓度水平低于其他大城市流域，但高于南北极表层水体.拉萨河中的主要化合物为全氟丁酸（PFBA）（25%）、全氟戊酸（PFPeA）（22%）、全氟辛酸（PFOA）（14%）、全氟辛烷磺酸（PFOS）（14%）和全氟丁烷磺酸（PFBS）（13%）.空间分布特征表明，拉萨河中全氟化合物的排放还存在一些点排放源，拉萨市产生的污水并未完全汇入到拉萨市污水处理厂中处理.基于PFBA和PFBS的全氟产品使用比较广泛，而基于PFOA和PFOS的全氟产品只在某些区域或行业有相对多的使用量或排量.PFASs在丰水期和枯水期的浓度水平和组成特征有显著的差异，拉萨全氟化合物产品的生产和使用模式受季节影响较大.污水处理厂是PFASs排放到拉萨河中的一个重要点源.污水处理厂每年排放到拉萨河中的全氟化合物约为37mg，拉萨河排放到雅鲁藏布江的物质荷载约为292t/a.在未来，所有的废水都应严格地纳入污水处理厂经达标处理后再排放.尽管PFOA和PFOS在拉萨的生产和使用进行了一定的转型，但是基于全氟化合物的产品的限制应进一步系统地执行和强有力地落实.

Special distribution and seasonal variation of perfluoroalkyls substances in Lhasa River Basin,China

The levels and compositions of 17 Perfluoroalkyls Substances (PFASs) were determined by UltiMate 3000DGLC-MS/MS for the first time in river water, wastewater of Lhasa, one of the highest plateau city (average elevation 3700m), during wet and dry season in 2016. Lhasa was commonly contaminated by PFASs. The average Σ₁₃ PFASs concentration of surface water of Lhasa River was 322pg/L, ranged from 60 to 1724pg/L. The predominant PFASs were short-chain pefluorobutanoate (PFBA) (25%), perfluoropentanoate (PFPeA) (22%), perfluorooctanoic acid (PFOA) (14%), perfluorooctanesulfonate (PFOS) (14%) and perfluorobutanesulfonate (PFBS) (13%). The spatial distribution of PFASs in Lhasa River revealed that the wastewater not totally assimilated into wastewater treatment plant, and Lhasa River basin was mainly polluted by point sources emission. There was a limited transform of production and use from PFOA and PFOS in Tibet. Seasonal variation of profiles and levels of PFASs in both wet and dry seasons suggested that the use and discharge schema of PFASs in Lhasa were influenced by season. The annual discharge load of PFASs from WWTP to Lhasa River was estimated to be 37mg/a, input amount of PFASs from The Lhasa River basin into YarlungZangbo River were estimated to be 292t/a. In the future, all the wastewater should be strictly incorporated into WWTP and PFASs-based product should be restrained.