摘要

       本研究的主要目的是调查废水 (WW) 中的抗生素抗性 (AR) 水平及其对接收河流的影响。在医院的污水处理厂、两个污水处理厂 (WWTP) 的原始污水处理厂和处理过的污水处理厂，以及污水处理厂污水排放到 Zenne 河的上游和下游（比利时）在一年内每个季节收集一次样本.培养依赖的方法用于量化对阿莫西林、磺胺甲恶唑、萘啶酸和四环素具有抗性的大肠杆菌和异养细菌。在颗粒附着 (PAB) 和自由生活 (FLB) 细菌中量化了六个抗生素抗性基因 (ARG)。我们的结果表明，污水处理厂有效地去除了抗生素抗性细菌 (ARB)，而不管其 AR 特征如何。 ARGs 水平在医院 WW 中最高，并且在两个 WWTP 中都显着降低。然而，ARB 和 ARGs 丰度在污水处理厂排放口下游的 Zenne 河中显着增加。通过 WW 处理的 ARGs 相对丰度的变化取决于所考虑的 WWTP、分数和基因。与两个污水处理厂的进水相比，PAB 部分中的 sul1 和 sul2 基因在出水中显示出显着更高的相对丰度。这项研究表明，污水处理厂可能是 AR 传播的热点，对接收淡水生态系统产生重大影响。这是第一项同时调查抗生素发生率、粪便细菌指标、异养细菌群落和 ARG（区分 PAB 和 FLB）的综合研究，以评估 WW 中的 AR 水平以及对接收河流的影响。

       The main objective of this study was to investigate the antibiotic resistance (AR) levels in wastewater (WW) and the impact on the receiving river. Samples were collected once per season over one year in the WW of a hospital, in the raw and treated WW of two wastewater treatment plants (WWTPs), as well as upstream and downstream from the release of WWTPs effluents into the Zenne River (Belgium). Culture-dependent methods were used to quantify Escherichia coli and heterotrophic bacteria resistant to amoxicillin, sulfamethoxazole, nalidixic acid and tetracycline. Six antibiotic resistance genes (ARGs) were quantified in both particle-attached (PAB) and free-living (FLB) bacteria. Our results showed that WWTPs efficiently removed antibiotic resistant bacteria (ARB) regardless of its AR profile. The ARGs levels were the highest in the hospital WW and were significantly reduced in both WWTPs. However, ARB and ARGs abundances significantly increased into the Zenne River downstream from the WWTPs outfalls. The variation in the relative abundance of ARGs through WW treatment differed depending on the WWTP, fraction, and gene considered. The sul1 and sul2 genes in PAB fraction showed significantly higher relative abundances in the effluent compared to the influent of both WWTPs. This study demonstrated that WWTPs could be hotspots for AR spread with significant impacts on receiving freshwater ecosystems. This was the first comprehensive study investigating at the same time antibiotics occurrence, fecal bacteria indicators, heterotrophic bacterial communities, and ARGs (distinguishing PAB and FLB) to assess AR levels in WW and impacts on the receiving river.

https://www.sciencedirect.com/science/article/abs/pii/S004565351830818X