Bleach versus peracetic acid

With a history dating back beyond the 18th century when scientists discovered the bleaching and disinfecting properties of chlorine and sodium hypochlorite, ‘bleach’ has been synonymous with effective cleaning. In its industrial usage, bleach is made up of sodium hypochlorite of which the active ingredient is chlorine. Its record of killing bacteria is unrivalled. It is the disinfectant of choice for many tasks such as hospital deep cleaning where it is required to kill aggressive bugs like salmonella, e-coli and the common cold.

However, the strong anti-bacterial properties of bleach which make it such a popular choice for many companies, are also the reasons which now make it unsuitable for so many other applications. It has the power to kill 99.9% of germs, but this means it can kill good bacteria too. Micro-organisms in our streams and waterways, and creatures at the very bottom of the food chain in the micro-environment could be wiped out by waste bleach too. Therefore, it’s unsuitable for the treatment of water, food manufacturing, bottling plants, dairy machines and similar functions.  

Consequently, this makes it a less popular product in some industries, particularly within an increasingly environmentally-conscious world where legislation aimed at protecting the ecosystem is growing all the time. Whereas the global peracetic acid market was estimated to be worth a huge £30 million in 2013, and is projected to reach almost £45 million by 2018.

The rise of PAA

Food and beverage cleaning was the largest segment of the global peracetic acid market, accounting for more than a 25% share in 2013. At Airedale Chemical, we have already seen a 32% increase in sales of PAA in the last 24 months. We predict an even greater surge in demand in the near future and consequently plan to grow the product by 20% in 2015. This increase in demand has largely been attributed to suppliers and end-users looking for an alternative to traditional sodium hypochlorite based bleach products.

Lesley Meredith, Airedale Chemical’s R&D chemist, says: "The relative newcomer to the industrial cleaning world, peracetic acid, also has many strengths. It is a strong disinfectant which is effective even at low temperatures and is a versatile product which is commonly used in food packaging and processing areas, circulation cleaning, sanitisation, in breweries, dairy and agrochemical trades. It is a highly effective biocide killing many micro-organisms. Importantly, at low levels it also rinses away completely leaving no chlorine residue."

She adds: "Unlike bleach, it does not linger in the environment, or on surfaces. PAA components are completely biodegradable as its base elements (hydrogen and water) are harmless. It is also a low corrosion risk. In contrast to some disinfectants which can affect metal surfaces, PAA has a much lower rate of corrosion than other similar products. This means it is suitable for cleaning use on many medical and dental instruments without fear of damage. 

"However, PAA can be more harmful when coming into contact with skin. Whereas bleach is generally viewed as a mild irritant, PAA has the potential to burn the skin even at low levels. Therefore, it is only really a viable option in industrial cleaning and is as yet not a possibility for domestic use."

While both bleach and PAA have their own distinct, well-deserved place in the industrial cleaning world, peracetic acid is definitely the cleaning industry’s rising star.