摘要

       抗生素耐药性正在成为全世界的一个非常大的问题。抗生素抗性细菌 (ARB) 和抗生素抗性基因 (ARG) 在环境中的传播是一个重大的公共卫生问题。水生生态系统是 ARB 和 ARG 的重要来源。饮用水处理系统专为消除饮用水中的细菌和病原体而设计。源水和饮用水中 ARB 和 ARGs 的存在可能会影响公众健康，这是饮用水行业的一个新兴问题。因此，本研究旨在研究路易斯安那州一家农村水处理厂的源水、处理过的饮用水（成品水）和配水管线（自来水）中 ARB 和 ARG 的存在情况。结果显示源水中存在多种 ARB，包括阴沟肠杆菌、肺炎克雷伯菌、大肠杆菌、假单胞菌、肠球菌、葡萄球菌和芽孢杆菌。然而，水处理厂有效地去除了处理水中的这些细菌，因为在自来水和水处理厂的成品水中均未发现这些细菌。在原水中观察到细菌 DNA，包括 16s rRNA 和磺胺类和四环素类抗生素的 ARGs。在每个月的原水、成品水和自来水采样中都一致地发现 16s rRNA 的存在。这表明处理厂的过滤系统在过滤掉细菌 DNA 的小片段方面是无效的。此外，供水管道中可能存在生物膜，由于饮用水中氯化的选择压力，生物膜可能会产生抗生素抗性。

       Antibiotic resistance is becoming a very large problem throughout the world. The spread of antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs) in the environment is a major public health issue. Aquatic ecosystem is a significant source for ARB and ARGs. The drinking water treatment system is designed specifically to eliminate bacteria and pathogens in drinking water. The presence of ARB and ARGs in source water and drinking water may affect public health and it is an emerging issue in drinking water industry. Therefore, this study was conducted to study the presence of ARB and ARGs in a source water, treated drinking water (finished water), and in the distribution line (tap water) in a rural water treatment plant in Louisiana. The results showed the presence of several ARB in the source water including, Enterobacter cloacae, Klebsiella pneumoniae, Escherichia coli, Pseudomonas, Enterococcus, Staphylococcus and Bacillus spp. However, the water treatment plant effectively removed these bacteria in the treated water as none of these bacteria were found in the tap water as well as in the finished water at the water treatment plant. Bacterial DNA including 16s rRNA and ARGs of sulfonamides and tetracycline antibiotics were observed in raw water. The presence of 16s rRNA was found consistently in every month of sampling in raw water, finished water, and tap water. This suggests that the filtration system at the treatment plant was ineffective in filtering out small fragments of bacterial DNA. Also, the possibility of the presence of biofilms in the water pipeline exists, which may develop antibiotic resistance due to the selective pressure of chlorination in drinking water.

https://www.sciencedirect.com/science/article/abs/pii/S0964830515001456