摘要
      本研究的目的是探讨家用净水器（HWP）对饮用水中新出现污染物的影响和去除，以及它们的分布特征。使用宏基因组学，在150天的操作后，通过五个步骤的过滤，对污染的过滤器、影响物和HWP废水中的抗生素抗性基因（ARGs）、移动遗传元件（MGE）、毒力因子基因（VFGs）和细菌群落进行了分析。结果表明，聚丙烯1μm（PP1）和纳滤膜（NM）中优势物种的多样性显著高于其他过滤器。后活性炭（AC）用于检测低物种丰富度或多样性，以及最高比例的优势物种，这导致饮用水中HWP废水的微生物风险更大。氯胺消毒过的过滤器中的优势菌属数高于氯消毒过的同一组。HWP的净化降低了水中细菌物种的丰富度或多样性，因为过滤元件有效地捕获了各种微生物。氯化和氯胺HWP废水中抗生素流出的相对丰度分别为5.58×10−3和4.60×10−3.这是主要的耐药机制。HWP废水中发现了高丰度的VFG，攻击性VFG的相对丰度显著高于防御性VFG。根据共现结果，243种ARGs亚型与VFGs共现，多种细菌被认为是ARGs的可能宿主，这表明HWP废水中VFGs的宿主细菌具有更强的攻击能力。仅采用过滤工艺的HWP出水会面临ARGs和VFG的风险。本研究有助于了解HWP的实际净化效果，并为生活饮用水中ARGs污染的管理和控制提供理论参考。
Abstract
The aim of this study was to explore the influence and removal of household water purifiers (HWPs) on emerging contaminants in drinking water, and their distribution characteristics. The antibiotic resistance genes (ARGs), mobile genetic elements (MGEs), virulence factor genes (VFGs) and bacterial communities were profiled in the fouled filters, influents, and effluents from HWPs with five steps of filtration after 150 days operation, using metagenomics. The results showed that the diversity of dominant species in Poly Propylene 1 μm (PP1) and nanofiltration membrane (NM) was significantly higher than that in other filters. Post-activated carbon (AC) was used to detect low species richness or diversity, and the highest proportion of dominant species, which contributes to the greater microbial risk of HWPs effluents in drinking water. The number of dominant bacterial genera in the filters disinfected with chloramine was higher than that in the same group disinfected with chlorine. The bacterial species richness or diversity in water was reduced by the purification of HWPs because the filter elements effectively trapped a variety of microorganisms. The relative abundance of Antibiotic efflux in the effluents of chlorinated and chloraminated HWPs was 5.58 × 10−3 and 4.60 × 10−3, respectively, which was the main resistance mechanism. High abundance of VFGs was found in HWPs effluents and the relative abundance of aggressive VFGs was significantly higher than those of defensive VFGs. Based on the co-occurrence results, 243 subtypes of ARGs co-occurred with VFGs, and a variety of bacteria were thought to be possible ARGs hosts, which indicated that the host bacteria of VFGs in HWP effluents had a stronger attack ability. The effluent of HWPs with only filtration processes is exposed to the risk of ARGs and VFGs. This study helps to understand the actual purification effect of HWPs and provides a theoretical reference for the management and control of ARGs pollution in domestic drinking water.

https://www.sciencedirect.com/science/article/abs/pii/S0048969722056716