Reactive oxygen species formulations as well as methods for making and using such formulations. Reactive oxygen species formulations comprising one or more parent oxidants, such as peroxides, or peroxyacids, and one or more reactive oxygen species (ROS). The formulations optionally contain in addition one or more reactive species other than ROS. The reactive oxygen species and other reactive species when present provide chemical reactivity, oxidative activity and/or antimicrobial activity not provided otherwise by the parent oxidant. The invention provides methods for making such formulation and applications of such formulations. In certain formulations, ROS and other reactive species are generated in situ in the formulation by an activation event, such as a change in pH to an activation pH, a change in temperature, irradiation with electromagnetic radiation or by the addition of one or more precursors or a combination of precursors. In certain formulations, peracid containing precursors are activated by adjusting the pH of the formulation to be within an activation pH range for generation of singlet oxygen. In other formulations, formulations containing peracid and superoxide also evolve singlet oxygen. Formulations containing different combinations of ROS exhibit differences in oxidation activity and antimicrobial activity.
