Occurrence of culturable Legionella pneumophila in drinking water distribution systems
Occurrence of culturable Legionella pneumophila in drinking water distribution systems
复制标题
饮用水分配系统中存在可培养的嗜肺军团菌
DOI：
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发表时间：
2019
期刊：
影响因子：
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通讯作者：
M. LeChevallier
中科院分区：
文献类型：
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作者：
M. LeChevallier
先前对12个饮用水分配系统的研究仅在576个样本中的一个（0.17%）中检测到嗜肺军团菌，但该调查是在冬季和春季进行的，当时水温通常低于15°C（LeChevallier，AWWA Water Science 2019，e1122）。10家公用事业公司同意在夏季和初秋月份参加第二轮测试，当时水温平均为23°C（平均温度为14至29°C）。L.使用Legiolert测定对嗜肺菌进行计数。在研究过程中，共分析了669个样品：50个源水样品，46个来自工厂废水，573个来自分配系统。L.在两个水源水样本中检测到嗜肺菌，而在任何经处理的工厂废水样本中均未检测到。L.在14个分配系统样本中检测到嗜肺菌，13个来自游离氯化系统，1个来自氯化系统。所有L的出现。当水温>18°C时，观察到嗜肺菌。L的浓度。除氯残留量小于0.1 mg/L外，嗜肺菌的最大可能数均小于10个/100 mL。根据这项研究的结果，建议自来水公司保持至少0.1 mg/L的余氯，特别是当水温>18°C时。
A prior study of 12 potable water distribution systems detected Legionella pneumophila in only one of 576 samples (0.17%), but the survey was conducted during winter and spring months when water temperatures were generally below 15°C (LeChevallier, AWWA Water Science 2019, e1122). Ten of the utilities agreed to participate in a second round of testing during the summer and early fall months when water temperatures averaged 23°C (average temperatures ranged from 14 to 29°C). L. pneumophila was enumerated using the Legiolert assay. A total of 669 samples were analyzed during the study: 50 source water samples, 46 from the plant effluent, and 573 from the distribution system. L. pneumophila was detected in two source water samples and not detected in any of the treated plant effluent samples. L. pneumophila was detected in 14 distribution system samples, 13 from free chlorinated systems and one from a chloraminated system. All occurrences of L. pneumophila were observed when water temperatures were >18°C. Concentrations of L. pneumophila were <10 most probable number/100 mL except when chlorine residuals were less than 0.1 mg/L. Based on the results of this study, it is recommended that water utilities maintain at least a 0.1 mg/L chlorine residual, particularly when water temperatures are >18°C.