Bactericidal Effect of Low Concentrations of Silver

THE effect of oligodynamic silver on organisms was first described in 1869.1 Since then it has frequentlybeen reported that silver added to water as a colloidal suspension, by filter beds or electrolytic devices, has greater bactericidal efficiency than an equivalent amount of silver added as silver nitrate. The results of most of the work have been unsatisfactory. There has been a need to: (1) improve the methods for determining silver in low concentrations; (2) recognize, and compensate for, the silver adsorbed by surfaces ; (3) devise a method for removing toxic silver residuals from equipment; (4) find neutralizers of proved capacity to arrest not only bactericidal but also bacteriostatic action; and (5) provide satisfactory controls.