State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.
College of Biological Science and Engineering, Fuzhou University, Fuzhou 350108, China.
Sci Total Environ. 2014 Sep 15;493:626-31. doi: 10.1016/j.scitotenv.2014.06.035. Epub 2014 Jun 29.
The occurrence and distribution of antibiotic resistance genes (ARGs) in drinking water treatment plants (DWTPs) and finished water are not well understood, and even less is known about the contribution of each treatment process to resistance gene reduction. The prevalence of ten commonly detected sulfonamide and tetracycline resistance genes, namely, sul I, sul II, tet(C), tet(G), tet(X), tet(A), tet(B), tet(O), tet(M) and tet(W) as well as 16S-rRNA genes, were surveyed in seven DWTPs in the Yangtze River Delta, China, with SYBR Green I-based real-time quantitative polymerase chain reaction. All of the investigated ARGs were detected in the source waters of the seven DWTPs, and sul I, sul II, tet(C) and tet(G) were the four most abundant ARGs. Total concentrations of ARGs belonging to either the sulfonamide or tetracycline resistance gene class were above 10(5) copies/mL. The effects of a treatment process on ARG removal varied depending on the overall treatment scheme of the DWTP. With combinations of the treatment procedures, however, the copy numbers of resistance genes were reduced effectively, but the proportions of ARGs to bacteria numbers increased in several cases. Among the treatment processes, the biological treatment tanks might serve as reservoirs of ARGs. ARGs were found in finished water of two plants, imposing a potential risk to human health. The results presented in this study not only provide information for the management of antibiotics and ARGs but also facilitate improvement of drinking water quality.
抗生素耐药基因（ARGs）在饮用水处理厂（DWTP）和饮用水中的出现和分布情况尚未得到充分了解，甚至对每个处理过程对抗生素耐药基因减少的贡献也知之甚少。本研究采用基于 SYBR Green I 的实时定量聚合酶链反应（qPCR）方法，调查了中国长江三角洲地区 7 个 DWTP 中十种常见的磺胺类和四环素类耐药基因（sul I、sul II、tet(C)、tet(G)、tet(X)、tet(A)、tet(B)、tet(O)、tet(M)和 tet(W)）和 16S-rRNA 基因的流行情况。在所调查的七个 DWTP 的水源水中均检测到了所有的抗生素耐药基因，而 sul I、sul II、tet(C)和 tet(G)是最丰富的四个抗生素耐药基因。磺胺类或四环素类抗生素耐药基因的总浓度均超过 10(5)拷贝/mL。处理过程对抗生素耐药基因去除的影响因 DWTP 的整体处理方案而异。然而，通过处理程序的组合，可以有效地降低耐药基因的数量，但在某些情况下，抗生素耐药基因与细菌数量的比例增加。在处理过程中，生物处理池可能是抗生素耐药基因的储存库。在两个水厂的饮用水中也发现了抗生素耐药基因，对人类健康构成潜在威胁。本研究的结果不仅为抗生素和抗生素耐药基因的管理提供了信息，还有助于提高饮用水质量。
