The invention provides a liquid composition containing (a) an acidic oxidant, (b) nitric acid or a salt thereof, and (c) at least one carboxylic acid selected from the group consisting of monocarboxylic acids, dicarboxylic acids, and tricarboxylic acids, or a salt thereof. The liquid composition can be used to disinfect or sterilize a subject that includes a portion made of an aluminum-based metal.