A copper-based additive at a concentration of 2.0 wt% (≤0.24 wt.% copper) has been shown to be antibacterial, antifungal and antiviral. Additive-modified surfaces show defense against Escherichia coli, MRSA, Klebsiella pneumonia, coronavirus 229E and toxic black mold. The micro-particle additives are not yet EPA approved. E-mail djvachon@iasismolecular.com.