Safe Handling of Peroxyacetic Acid

Peroxyacetic acid, abbreviated as PAA or POAA, is used by food processors as a post-rinse sanitizer for food contact surfaces. It is also used as an antimicrobial added to process water or applied directly to food products to kill pathogenic bacteria. PAA is a stabilized blend of hydrogen peroxide and acetic acid that is highly effective as a sanitizer or antimicrobial intervention. It is environmentally friendly and rapidly breaks down after use to water, acetic acid (vinegar) and oxygen. As such, it is suitable for use as a sanitizer in facilities that produce USDA organic products.

In its concentrated form, PAA is considered a hazardous material and must be treated with respect; it is both an oxidizer, and corrosive. It causes instant skin and eye burns on contact and may cause fires if the concentrate is allowed to soak into organic materials such as wood, rags or oily material. Despite these concerns it is an effective, economical product that is safe to use when handled properly. PPE or personal protective equipment is essential when handling or dispensing the concentrate. At a minimum, chemical-resistant gloves (Neoprene) and splash-proof eye protection should be worn. Adding a face shield is appropriate if working with larger quantities.  Concentrated PAA has a pungent odor (acetic acid) and should only be handled in a well-ventilated area. Prolonged exposure may require the use of a suitable respirator.

PAA decomposes slowly during storage, giving off oxygen, and should be stored in appropriately vented containers. It is also important to use appropriate materials when sourcing dosing or transferring equipment for concentrated PAA. Glass, polyethylene (HDPE/LLDPE) and Teflon (PTFE) are all suitable for handling concentrated solutions. Stainless steel and other polymers should only be used where exposure is short term. Once diluted to the “at use” concentration (usually 100 ppm – 200ppm), most materials except Tygon and rubber are suitable.

PAA products such as Birko’s Birk-Ox™ sanitizer or the Birkoside MP-2™ antimicrobial intervention can be effective tools in your food safety program provided they are handled with appropriate precautions. As with any chemical product make sure that you read and understand the MSDS completely before handling or use.

Elis Owens, Ph.D., Director, Technical Services, Birko, can be reached at [email protected], 303-289-1090.