A sterilization indicator for oxidative sterilants, comprising a first compartment comprising spores of one or more microorganism species, wherein the spores have been pretreated with and comprises a compound comprising a transition metal ion that is reactive with an oxidative sterilant; a second compartment comprising a growth medium and adapted to combine contents of the first compartment with contents of the second compartment for incubation after the sterilization indicator has been exposed to an oxidative sterilant; and an agent disposed in the growth medium and selected to indicate viability of the spores after the sterilization indicator has been exposed to the oxidative sterilant.