摘要

       人工湿地 (CW) 在去除药物活性化合物 (PhAC) 方面的性能通常基于化学分析进行评估。在这项工作中，我们结合化学、毒理学和分子分析来评估 PhAC、毒性效力和抗生素抗性基因 (ARG) 的衰减，这是对用作废水处理厂三级处理的三个 CW 的实地研究。首先，对 17 种 PhAC 进行了化学分析，其中 14 种被检测到，7 种浓度 >0.1 μg/l。尽管在所调查的 CW 中一些单独的 PhAC 被中等或高度去除，但在垂直地下流 CW (VSF-CW) 中，整体 PhAC 的去除中值约为 50%，具有较低的水力加载速率，而其他两个去除自由水面流动 CWs (SF-CWs) 可以忽略不计。其次，在一系列生物测定中评估了废水提取物的毒性效力。雌激素在 CW 中总体减弱，而废水提取物的神经毒性效力在通过所研究的两个 CW 后没有降低。第三，VSF-CW 和其中一个 SF-CW 显示整合酶基因的阳性去除和测试的三个 ARG。其他 SF-CW 中 ARGs 浓度的增加，以及所有 CW 中总细菌的增加，可能与携带抗药性细菌的再生有关。最后，多变量分析表明，大多数 PhAC 与观察到的毒性呈正相关。此外，有机物和营养物的低去除率似乎与 PhAC 的低去除率相似。 ARGs 与有机物、营养素和一些 PhACs 以及整合酶基因呈正相关，但与相应的抗生素无关。 PhACs、毒性效力和 ARGs 的去除不足表明需要优化设计 CWs 作为三级处理设施。

       The performance of constructed wetlands (CWs) in the removal of pharmaceutically active compounds (PhACs) is generally evaluated on the basis of chemical analysis. In this work, we used a combination of chemical, toxicological, and molecular analyses to assess the attenuation of PhACs, toxic potency and antibiotic resistance genes (ARGs) in a field study of three CWs serving as tertiary treatment of wastewater treatment plants. First, 17 PhACs were analysed chemically, of which 14 were detected and seven at concentrations >0.1 μg/l. Even though some of the individual PhACs were moderately or highly removed in the CWs investigated, median removal of overall PhACs was approximately 50% in the vertical subsurface flow CW (VSF-CW) with a lower hydraulic loading rate while the removal in the other two free water surface flow CWs (SF-CWs) was negligible. Second, toxic potency of wastewater extracts was assessed in a range of bioassays. Estrogenicity was overall attenuated in CWs, while the neurotoxic potency of wastewater extracts did not decrease after passage through the two CWs investigated. Third, the VSF-CW and one of the SF-CW showed a positive removal of an integrase gene and three ARGs tested. The increased concentrations of ARGs in the other SF-CW, as well as the increase of total bacteria in all CWs, may relate to regrowth of resistance-carrying bacteria. Finally, multivariate analysis shows that most PhACs are positively correlated to the observed toxic potency. Additionally, low removal of organics and nutrients seems to parallel with low removal of PhACs. ARGs positively correlated with organics, nutrients and some PhACs, and the integrase gene but not to the respective antibiotics. The insufficient removal of PhACs, toxic potency, and ARGs indicates the need of an optimal design of CWs as tertiary treatment facilities.

https://www.sciencedirect.com/science/article/abs/pii/S0048969718308374