The bactericidal, fungicidal and sporicidal properties of hydrogen peroxide and peracetic acid

The antimicrobial properties of aqueous solutions of peracetic acid and hydrogen peroxide have been compared. Peracetic acid exhibited excellent antimicrobial properties, especially under acidic conditions. Reductions by a factor of 10(6) in the numbers of vegetative bacteria are obtained within 1 min at 25 degrees C using a solution containing 1.3 mmol/l of peracetic acid. Rapid activity against bacterial spores and yeasts also occurs. Hydrogen peroxide is more effective as a sporicide than as a bactericide, with sporicidal action being obtained using a solution containing 0.88 mol/l. Bactericidal action is poor but hydrogen peroxide was bacteriostatic at concentrations above 0.15 mmol/l.