Rohr U, Senger M, Selenka F, Turley R, Wilhelm M
Institut für Hygiene und Mikrobiologie, Abteilung für Hygiene, Sozial- und Umweltmedizin, RuhrUniversität Bochum, Universitätsstr. 44801 Bochum, Germany.
Clin Infect Dis. 1999 Dec;29(6):1507-11. doi: 10.1086/313512.
Silver-copper ionization was used for controlling Legionella distribution in a German university hospital hot water plumbing system for 4 years. In the beginning, silver concentrations were not allowed to exceed 10 microg/L because of drinking water regulation limits in Germany. Water samples were monitored for Legionella counts, temperature, and silver and copper concentrations. A significant (P<.001) 3.8-log reduction of Legionella counts, from 40, 000 cfu/L to 7 cfu/L, was found during the first year with silver-copper ionization. Nevertheless, the long-term efficacy of silver concentrations <10 ,++microg/L was not sufficient. Legionella counts increased to 10,000 cfu/L during the third year. During the fourth year, we studied the influence of higher silver concentrations on Legionella distribution. With an average silver level of 30 microg/L, only a 1.3-log reduction in Legionella, to 500 cfu/L, was achieved. The effect was not significant (P=.071); therefore, it must be considered that Legionella developed a tolerance to silver ions.
银铜离子化技术被用于德国一家大学医院的热水管道系统中控制军团菌分布，为期4年。起初，由于德国饮用水规定限制，银浓度不得超过10微克/升。对水样进行军团菌计数、温度以及银和铜浓度的监测。在使用银铜离子化技术的第一年，军团菌计数显著（P<0.001）下降了3.8个对数级，从40,000 cfu/升降至7 cfu/升。然而，银浓度<10微克/升的长期效果并不充分。在第三年，军团菌计数增加到10,000 cfu/升。在第四年，我们研究了较高银浓度对军团菌分布的影响。银平均水平为30微克/升时，仅使军团菌减少了1.3个对数级，降至500 cfu/升。该效果不显著（P = 0.071）；因此，必须考虑军团菌已对银离子产生了耐受性。
