Brass can really disinfect itself--certain metals have been found to inactivate bacteria, including staphylococcus and E.Coli, that can cause disease. For example, brass doorknobs have been found to automatically disinfect themselves within eight hours and are often selected as a sanitary option for healthcare facilities. Brass has also been found to destroy fungi by 99% within six hours, according to a University of Southampton study. This disinfecting property is due to what is referred as the oligodynamic effect, in which ions from metals denature proteins in bacteria cells. Brass and other metals, such as copper or silver, tend to be most effective at destroying bacteria rather than viruses.
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