摘要

    抗生素和抗生素抗性基因（ARG）是地表水（特别是饮用水水源）中正在出现的污染物，它们可能对人体健康和水生生态构成威胁。饮用水水库中建造的生态净化设施旨在保护水质。但是，它们从水中去除抗生素和ARG的能力以及此类河流水库系统中ARG的存在尚未得到全面表征。在中国上海一个典型的河流—水库系统中，研究了抗生素，ARG和流动遗传元素（MGE）的发生，分布和时空变化。使用高通量定量PCR分析，水中总共检测到283个ARG和12个MGE。当河流中的水经过水库的生态净化过程后，水库流入水中的抗生素残留量和总ARGs和MGEs的绝对含量会大大降低。该河流水库系统中的抗生素对水生生态系统和人类健康的危害有限。在ARGs的分布模式和时空因素之间没有观察到显着的相关性。占优势的ARGs与整合素密切相关。通过冗余分析和变异分区分析，我们确定MGEs是改变ARGs分布的主要驱动力，环境因素和抗生素残留的影响反映在与MGEs的联合作用中。小型生态水库被证实是减轻饮用水源中生态风险的有效工程。

    Antibiotics and antibiotic resistance genes (ARGs) are emerging contaminants in surface waters, especially drinking water sources, where they can pose a risk to human health and aquatic ecology. The ecological purification facilities constructed in the drinking water reservoirs are intended to safeguard water quality. However, their ability to remove antibiotics and ARGs from the water and the presence of ARGs in such river-reservoir systems have not been comprehensively characterized yet. The occurrence, distribution and spatiotemporal variations in antibiotics, ARGs, and mobile genetic elements (MGEs) were investigated in a representative river-reservoir system in Shanghai, China. A total of 283 ARGs and 12 MGEs were detected in the water using high- throughput quantitative PCR analysis. Antibiotic residues and the absolute abundance of total ARGs and MGEs in reservoir inflow were significantly reduced when water from the river passed through the ecological purification processes in the reservoir. Antibiotics in this river-reservoir system posed only limited risks to the aquatic ecosystem and human health. No significant correlation was observed between the distribution pattern of ARGs and spatiotemporal factors. The dominant ARGs were strongly and significantly correlated with integrons. Through redundancy analysis and variation partitioning analysis, we determined that MGEs were the major driver shifting the distribution of ARGs, and the effects of environmental factors and antibiotic residues were reflected in the joint effects with MGEs. The small ecological reservoir was verified as an effective engineering to mitigate ecological risk in the drinking water source.

    https://www.sciencedirect.com/science/article/abs/pii/S0048969719352684