摘要

       抗生素抗性基因 (ARG) 越来越被认为是重要的微污染物。由于人类活动间接产生，它们被释放到环境中，因为它们不是传统废水处理的目标。为了了解城市污水处理厂 (WWTP) 中 ARG 和其他抗性形式（例如，表型适应性）的归宿，我们监测了三个具有不同消毒过程（氯、过氧乙酸 (PAA) 和紫外线 (UV) ))。我们在 24 小时内监测了污水处理厂的流入和消毒前后的流出物，然后进行了持续 96 小时的孵化实验。我们测量了细菌丰度、大小分布和聚集行为、完整（活性）细胞的比例以及四种 ARG 和移动元素整合子的丰度。虽然所有污水处理厂的所有预消毒处理都去除了大部分细菌和相关的 ARG，但在消毒过程中，只有 PAA 有效地去除了细菌细胞。然而，PAA 施加的压力选择细菌聚集体，并且与氯类似，在孵育实验期间刺激了 ARG 的选择。这表明基于对细菌细胞结构的化学侵蚀性破坏的消毒可以促进残留的微生物群落，该微生物群落对抗生素更具抗性，并且鉴于聚集行为的改变，对自然界中的竞争压力具有更强的抵抗力。

       Antibiotic resistance genes (ARGs) are increasingly appreciated to be important as micropollutants. Indirectly produced by human activities, they are released into the environment, as they are untargeted by conventional wastewater treatments. In order to understand the fate of ARGs and of other resistant forms (e.g., phenotypical adaptations) in urban wastewater treatment plants (WWTPs), we monitored three WWTPs with different disinfection processes (chlorine, peracetic acid (PAA), and ultraviolet light (UV)). We monitored WWTPs influx and pre- and postdisinfection effluent over 24 h, followed by incubation experiments lasting for 96 h. We measured bacterial abundance, size distribution and aggregational behavior, the proportion of intact (active) cells, and the abundances of four ARGs and of the mobile element integron1. While all the predisinfection treatments of all WWTPs removed the majority of bacteria and of associated ARGs, of the disinfection processes only PAA efficiently removed bacterial cells. However, the stress imposed by PAA selected for bacterial aggregates and, similarly to chlorine, stimulated the selection of ARGs during the incubation experiment. This suggests disinfections based on chemically aggressive destruction of bacterial cell structures can promote a residual microbial community that is more resistant to antibiotics and, given the altered aggregational behavior, to competitive stress in nature.

https://pubs.acs.org/doi/abs/10.1021/acs.est.6b02268