摘要

    全世界都使用家庭净水系统（HWPS）来获得干净的饮用水。但是，HWPS在提供安全水方面的可靠性未知或未经充分证明。在这项研究中，在26个房屋和一个实验室中研究了自来水，废水和HWPS过滤器中抗生素和抗生素抗性基因（ARG）的发生情况。在自来水中，抗生素和ARGs的水平分别低于检出限（LOD）和7.9 ng / L，以及低于LOD和3.45×105拷贝/ L。带有新鲜过滤器的HWPS去除抗生素和ARG的效率很高，去除率分别为91–92％和0.46–2.43 log。但是，经过长期手术（例如，超过三个月），一些HWPS的抗生素和ARG去除率较低（分别为3-79％和0.03-0.15 log），并且某些HWPS释放出的抗生素和ARGs进入了废水中。废水中的抗生素和ARGs含量要高于废水中的抗生素和ARGs水平。在研究的HWPS的许多过滤器上观察到生物膜。在过滤器上检测到的ARG的相对丰度（ARG的丰度与16S rRNA的丰度之比）为2.56×10-8–2.89×10-2。高通量测序分析表明，变形杆菌，酸性杆菌，绿弯曲菌和拟杆菌是最主要的菌种，而丙酸杆菌和丙酸杆菌是最主要的菌种。蓝细菌，杆状杆菌，拟杆菌和变形杆菌的丰度与ARGs的丰度显着正相关。通常在HWPS中观察到的微生物生长和富集会加速抗生素和ARG对这些设备的用水用户造成的暴露风险。

    Home water purification systems (HWPSs) are utilized worldwide to obtain clean drinking water. However, the reliability of HWPSs in providing safe water is unknown or not well-proven. In this study, the occurrences of antibiotics and antibiotic resistance genes (ARGs) in tap water, effluents, and filters of HWPSs were investigated in twenty-six houses and one laboratory. The levels of antibiotics and ARGs were between less than the limit of detection (LOD) and 7.9 ng/L and between less than LOD and 3.45 × 105 copies/L, respectively, in tap water. HWPSs with fresh filters had a high efficiency in removing antibiotics and ARGs, with removal rates of 91–92% and 0.46–2.43 log, respectively. However, after long-term operation (e.g., more than three months), some HWPSs had low removal rates of antibiotics and ARGs (3–79% and 0.03–0.15 log, respectively) and some HWPSs released antibiotics and ARGs into the effluents leading to higher levels of antibiotics and ARGs in the effluents than those in the influents. Biofilms were observed on many filters of the investigated HWPSs. ARGs were detected on the filters with relative abundances (the ratio of the abundance of ARGs to the abundance of 16S rRNA) of 2.56 × 10−8–2.89 × 10−2. High-throughput sequencing analysis showed that Proteobacteria, Acidobacteria, Chloroflexi, and Bacteroidetes were the dominant phyla, and Alphaproteobacteria and Gammaproteobacteria were the dominant classes. The abundances of Cyanobacteria, Patescibacteria, Bacteroidetes, and Proteobacteria were significantly positively correlated with the abundances of ARGs. Microbial growth and enrichment commonly observed in HWPSs can accelerate the exposure risk posed by antibiotics and ARGs to the consumers of water from these appliances.

    https://www.sciencedirect.com/science/article/abs/pii/S0043135420312951