Abstract: A first embodiment of the present invention is directed to an aqueous disinfectant solution comprising an alkali metal or alkaline earth metal hypochlorite, an amount of base sufficient to raise the pH of the solution to at least 12, and water. A second embodiment of the present invention is directed to a method for sterilizing medical and dental instruments and hard surfaces which comprises contacting the medical or dental instruments or hard surfaces with an aqueous disinfecting solution comprising an alkali metal or alkaline earth metal hypochlorite, an amount of a base sufficient to raise the pH of the solution to at least 12, and water, for a time sufficient to disinfect the medical or dental instruments or hard surface.