武汉地区水环境中全氟化合物污染水平及其分布特征

Occurrence and Distribution of Per-and Polufluoroalkyl Substances in Waste Water and Surface Water Samples in Wuhan

武汉作为中国氟化工行业的主要生产基地之一,其水环境中全氟及多氟类化合物(PFASs)污染情况对评估该地区水环境生态安全至关重要。采集了武汉城区10个污水处理厂进、出口污水和19个地表水样品,利用HPLC-ESI-MS/MS技术分析研究该区域水环境中PFASs污染水平及其分布特征。结果发现,武汉地区的污水和地表水样品中,PFASs污染均以短链同系物全氟丁酸(PFBA)和全氟丁基磺酸(PFBS)为主。污水处理厂进、出口污水中PFASs总浓度分别为11.8~12 700 ng·L^(-1)和19.1~9 970 ng·L^(-1)。在城区15个湖水样品中,PFASs总浓度为21.0~10 900 ng·L^(-1);在流经城区的4个江水样品中,PFASs总浓度为4.11~4.77 ng·L^(-1),比湖水样品中PFASs浓度水平低1~2个数量级。与污水中PFASs空间分布趋势一致,各湖泊水样中PFASs总体水平呈现汉口<汉阳<武昌的趋势,表明城市工业布局与人口密度程度直接影响城市PFASs污染空间分布。值得注意的是,与以往水环境中PFASs污染以全氟辛酸(PFOA)和全氟辛基磺酸(PFOS)为主不同,武汉地区水环境中PFASs污染以短链同系物为主,表明短链替代效应已经渐渐在中国化工领域出现,中国全氟行业在响应国际组织规范和建议的基础上做出了实质性进展。然而,对于短链PFASs的污染特征、迁移运输以及生态风险等科学问题,还需要更进一步的研究。

Wuhan was one of the production bases of the fluorochemical industry in China. Occurrence and distribution of per- and polufluoroalkyl substances （PFASs） in ten major wastewater treatment plants （WWTPs） and nineteen surface water samples from lakes and river were investigated in Wuhan using a high performance liquid chromatograph equipped with an electrospray ionization tandem mass spectrometer （HPLC-ESI-MS/MS）. Short-chain homologs, such as perfluorobutanoic acid （PFBA） and perfluorobutane sulfonate （PFBS）, were the dominant PFASs in wastewater and surface water samples. The total PFASs concentrations in influents and effluents collected from WWTPs were in a range of 11.8-12 700 ng ·L^-1 and 19.1-9 970 ng ·L^-1, respectively. The total PFASs concentrations in lake water samples ranged from 21.0 to 10 900 ng ·L^-1, while the total PFASs levels in river water samples were 1-2 order of magnitudes lower than those in lake water samples, in a range of 4.11-4.77 ng· L^-1. Consistent with the trend of spatial distribution in waste water samples, the total PFASs levels in Hankou were lower than those in Hanyang, and the highest levels of PFASs were observed in samples from Wuchang where was covered with factories and dense population, indicating that industrialization and population density were the primary factors affecting the PFASs levels. It’s worth noting that short-chain homologs were the dominant PFASs in water samples, which was different from those in previous studies. These results corroborated with the premise that short-chain PFASs are emerging in China as replacements. However, further research should be performed to determine the levels, transport, and ecological effect of short-chain PFASs.