Enhanced Toxicity of Ozone-Hydrogen Peroxide Mixtures

Abstract

Concern over enhanced toxicity of air pollutant mixtures has led to the experimental demonstration that hydrogen peroxide (H₂ O₂ in concentrations of a few ppm killed animals after a brief exposure when inhaled with a nonlethal concentration (1 ppm) of ozone (O₃). It was possible also to demonstrate a moderate degree of protection against otherwise lethal doses of H₂0₂, by a single prior exposure to H₂O₂. Moreover, cross tolerance against the organic peroxide, cumene hydroperoxide was afforded also by a prior exposure to H₂0₂. Particularly noteworthy, was a tolerance produced by a prior exposure to O₃ to mixtures of H₂0₂ and O₃, despite the fact that such mixtures normally show enhanced toxicity.