摘要

       在饮用水源中广泛检测到抗生素耐药性，威胁其安全和人类健康，因此在饮用水系统中去除抗生素抗性基因（ARGs）值得进一步关注。在这项研究中，整合酶基因 intI1 和 41 个 ARG 亚型的发生和减少研究了饮用水处理中对六种抗生素类别（β-内酰胺、氨基糖苷类、大环内酯、四环素、磺胺和喹诺酮）的抗性工厂 (DWTP)。在原水中检测到17个绝对浓度范围为1.4×100至7.3×105和3.9×104基因/mL（intI1）的ARG亚型； sul1 和 sul2 是两种主要的 ARG 亚型。总体而言，与原水中的 ARG 相比，整个 DWTP 实现了 0.03-2.4 个对数减少的 ARG。在传统工艺和先进工艺中，sul1、strA 和 intI1 的还原效率最高（1.0-2.4 log）。然而，成品水中 sul1、sul2 和 ermC 的水平仍然很高（1.3×100–1.9×104 个基因/mL）。处理单元包括预絮凝/沉淀/砂滤和臭氧处理单元，有利于减少 ARGs，这主要归因于生物量的下降和臭氧的强氧化性。然而，颗粒活性炭和氯化装置随后抵消了还原效果。这项研究提供了饮用水系统中 ARG 污染的基础数据，并表明 ARGs 仍然存在于饮用水中，即使经过传统的氯化或高级处理工艺，这凸显了对新型高效水净化技术的需求。

       Antibiotic resistance is extensively detected in drinking water sources, threatening its safety and human health, which deserves further attention to the removal of antibiotic resistance genes (ARGs) in the drinking water system. In this study, the occurrence and reduction of integrase gene intI1 and forty-one ARG subtypes, which confers resistance to six antibiotic classes (β-lactam, aminoglycoside, macrolide, tetracycline, sulfonamide, and quinolone), were investigated in a drinking water treatment plant (DWTP). Seventeen ARG subtypes with absolute concentrations ranging from 1.4 × 100 to 7.3 × 105 and 3.9 × 104 genes/mL (intI1) were detected in the raw water; and sul1 and sul2 were the two dominant ARG subtypes. Overall, the whole DWTPs achieved 0.03–2.4 log reduction of ARGs compared with those presented in raw water. The reduction efficiencies of sul1, strA, and intI1 were the highest (1.0–2.4 log) in both conventional and advanced processes. However, the levels of sul1, sul2, and ermC still remained high (1.3 × 100–1.9 × 104 genes/mL) in finished water. The treatment units, including pre-flocculation/sedimentation/sand filtration, and ozonation units, were beneficial for the reduction of ARGs, which was mostly ascribed to the decline in biomass and the strong oxidizing properties of ozone. However, the reduction effect was subsequently counteracted by the granular activated carbon and chlorination units. This study provides basic data for ARG pollution in the drinking water system, and suggests that ARGs persist in drinking water, even after conventional chlorination or advanced treatment processes, highlighting the need for new and efficient water purification technologies.

https://www.sciencedirect.com/science/article/abs/pii/S0048969719311258