Simple solutions of hydrogen peroxide; peroxide activators such as carbonate, bicarbonate, and molybdate; and organic cosolvents afford rapid, broad-spectrum decontamination of chemical warfare agents, even at low temperatures (-30 degreesC). Such solutions are nontoxic, noncorrosive, and environmentally friendly. With bicarbonate activator, the decon solution can be comprised solely using food-grade materials. In situ generation of peroxy anion OOH- effects perhydrolysis of the nerve agents O-ethyl-S-[2-(diisopropylamino)ethyl]-methylphosphonothioate (VX) and pinacolyl methylphosphonofluoridate (GD or Soman) to yield nontoxic products. For the blister agent bis(2-chloroethyl) sulfide (HD or mustard), peroxo species HCO4- and Mo(OO)(4) (2-) afford oxidation, initially, to the nonvesicant sulfoxide.