A sporicidal composition has a moderately low pH and includes at least one oxidizing acid and the dissociation product of at least one inorganic oxidizing agent. Very high effective solute concentrations can enhance the efficacy of the composition. Embodiments of the composition can be applied to a surface and allowed to absorb into the endospore ultimately killing at least some of those bacteria in mature endospore form. The surface being treated can be an inanimate surface particularly a hard surface or a medical device.