College of the Environment, Liaoning University, Shenyang 110036, China.
Key Laboratory of Environmental Biotechnology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.
J Hazard Mater. 2024 Nov 5;479:135617. doi: 10.1016/j.jhazmat.2024.135617. Epub 2024 Aug 22.
PFOA has garnered heightened scrutiny for its impact on denitrification, especially given its frequent detection in secondary effluent discharged from wastewater treatment plants. However, it is still unclear what potential risk PFOA release poses to a typical advanced treatment process, especially the sulfur-based autotrophic denitrification (SAD) process. In this study, different PFOA concentration were tested to explore their impact on denitrification kinetics and microbial dynamic responses of the SAD process. The results showed that an increase PFOA concentration from 0 to 1000 μg/L resulted in a decrease in nitrate removal rate from 9.52 to 7.73 mg-N/L·h. At the same time, it increased nitrite accumulation and NO emission by 6.11 and 2.03 times, respectively. The inhibitory effect of PFOA on nitrate and nitrite reductase activity in the SAD process was linked to the observed fluctuations in nitrate and nitrite levels. It is noteworthy that nitrite reductase was more vulnerable to the influence of PFOA than nitrate reductase. Furthermore, PFOA showed a significant impact on gene expression and microbial community. Metabolic function prediction revealed a notable decrease in nitrogen metabolism and an increase in sulfur metabolism under PFOA exposure. This study highlights that PFOA has a considerable inhibitory effect on SAD performance.
全氟辛酸（PFOA）因其对脱氮的影响而受到高度关注，尤其是在污水处理厂排放的二级废水中频繁检测到 PFOA。然而，目前尚不清楚 PFOA 释放对典型高级处理过程（特别是基于硫的自养反硝化（SAD）过程）可能带来的潜在风险。在这项研究中，测试了不同的 PFOA 浓度，以探讨其对 SAD 过程脱氮动力学和微生物动态响应的影响。结果表明，PFOA 浓度从 0 增加到 1000μg/L，导致硝酸盐去除率从 9.52 降低到 7.73mg-N/L·h。同时，亚硝酸盐积累和 NO 排放分别增加了 6.11 倍和 2.03 倍。PFOA 对 SAD 过程中硝酸盐和亚硝酸盐还原酶活性的抑制作用与观察到的硝酸盐和亚硝酸盐水平波动有关。值得注意的是，亚硝酸盐还原酶比硝酸盐还原酶更容易受到 PFOA 的影响。此外，PFOA 对基因表达和微生物群落也有显著影响。代谢功能预测显示，在 PFOA 暴露下，氮代谢显著减少，硫代谢增加。本研究表明，PFOA 对 SAD 性能具有相当大的抑制作用。
