ECJ EUROPEAN Cleaning Journal

There have been many products tried and tested in the realm of hospital and healthcare in the quest to discover the most effective cleaner in an industry where hygiene is paramount.

Adam Duxbury, new product development chemist at specialist chemical company, Airedale Chemical, explains why there is a new hero product emerging that is ticking all the boxes for hospital buyers: peracetic acid (PAA).

The healthcare profession’s search to find the most effective cleaning products and methods is an ongoing pursuit with no clear ‘winner’ as yet, with several chemicals and solutions each with their own strengths and weaknesses. However, in recent years, peracetic acid (PAA) has emerged as the disinfectant of choice over other traditional methods of disinfection in healthcare environments.

Unlike bleach (sodium hypochlorite), it does not linger on surfaces. PAA components are completely biodegradable to its base elements of hydrogen peroxide and acetic acid.  In comparison to bleach, which requires rinsing after use, PAA does not need to be rinsed off surfaces. When used correctly, it can be used to sanitise surfaces, vessels, closed systems and equipment safely, ensuring surfaces remain sanitised until required.

This effective bactericide disinfectant, which also acts as a fungicide and sporicide is a broad spectrum product, generally considered a more powerful alternative to hydrogen peroxide. It breaks down the permeability of cell walls and oxidises enzymes, metabolites and proteins.
PAA rinses away completely, leaving no residue but is still able to kill many micro-organisms. It is often used as a destainer in laundry applications and is highly effective at low temperatures.

The low corrosion risk, which is in contrast to some disinfectants that can affect metal surfaces, means it can be safely used for the cleaning of many medical and dental instruments without having to worry about damage occurring.

It is now one of the most frequently used disinfectants for the sterilisation of medical devices such as endoscopy equipment as it has such potent disinfecting qualities but doesn’t leave behind any toxic deposits which could jeopardise patients’ health.

With efficiency being so high on the agendas of health authorities, the fact that PAA has such a long shelf life, coupled with its environmental credentials mean it is increasingly becoming the product which gives buyers value for money.

Only very low concentrations are required to achieve effective disinfection, particularly in comparison to bleach and hydrogen peroxide, where overdosing is a common mistake - making PAA not only a cost effective, efficient disinfecting choice but also a safer alternative for hospitals and end users.

Despite the many advantages of using PAA, there are still other products which have proven popular in the past and still hold a place in certain areas of healthcare hygiene.

Back to basics: bleach

Sodium hypochlorite is still used extensively in hospitals as a disinfection agent because the CRAs (chlorine release agents) it contains are highly effective for disinfection purposes although it is generally classed as an intermediate level disinfectant.

Its stain removal properties make it an ideal choice for cotton fabrics such as towels and bed linen which are prone to staining and tend to mark most easily, but can be recovered with bleach.

Unfortunately over-bleaching of this type of fabric item can compromise the fibre structure, diminishing the lifespan of sheets and other textiles. Neither are coloured fabrics suitable for sodium hypochlorite bleaching because of the effect it can have on the dye.

Bleach is still commonly used to disinfect blood spillages on hard surfaces and has been proven to remove the HIV and Hepatitis B virus when in the form of CRAs. These CRAs are so effective because they destroy the cellular activity of proteins and are highly active oxidising agents.

Sodium hypochlorite displays significant levels of sporicidal and virucidal eradication and has generally been accepted as the most effective defence against the digestive system infection clostridium difficile (C.Diff).

It is easy to see why it has played such a large part in the cleaning routines of hospitals and healthcare institutions. Its price point and low toxicity value mean it is still an essential part of the process today and is likely to be around for many years to come.

However it is not without disadvantages. It must be rinsed well from all surfaces due to its corrosive nature and while it is effective at killing microorganisms, the breakdown products from chlorine bleach can be harmful by-products and can be detrimental to aquatic animals and other creatures found in our waterways.

Bleach also contains products that are not compatible with certain types of materials and can have adverse reactions. Anyone handling sodium hypochlorite needs to wear appropriate PPE to avoid harm caused by exposure to the liquid or its vapours, which can be an additional cost and risk to health authorities and healthcare businesses.

The best of the rest

Hydrogen peroxide makes a great alternative to some other sterilisers which can be toxic which is why it is still used to disinfect some equipment such as endoscopy tools.

It is an effective bactericidal, virucidal, fungicidal and sporicidal making it a long-standing and popular option for high-level disinfection and sterilisation in the healthcare industry. It can also be used in a vapour form to clean rooms (HPV).

Ultra-violet light (UV) uses no chemicals so has been a popular alternative to traditional cleaning products in hospital cleaning and has been found to be effective against pathogens which are resistant to drugs and in particular to antibiotics.

It is used in sealed cabinets in which high energy UV light is emitted and disturbs the DNA of microorganisms, bacteria and other viruses by breaking bonds and inhibiting cellular functions.
UV is mutagenic to bacteria, viruses and other microorganisms. It kills or disables microorganisms which have little or no UV protection.

UV can be highly effective, however the capital investment of equipment associated with this type of disinfection is high and users would need specialist training to operate it safely. This is potentially prohibitive and means the safety of the user of UV disinfection equipment remains a continual concern. Therefore its use and practicality in hospital cleaning remains limited.

At the other end of the technology spectrum, the easy-to-use disinfectant trigger spray cleaning products are still used widely in the healthcare sector. Often found in the forms of chlorine releasing agents such as chlorides, isothiaolinones, alkonium and dimethylammonium, trigger sprays are at risk of leaving behind residue as they need to be in contact with surfaces for at least five minutes to be fully effective.

This residue could have serious implications in hospitals and healthcare establishments as it could affect food preparation and medication handling areas. So despite their simplicity it is easy for these products to be used incorrectly - which would be dangerous to human health in a healthcare environment.

What next for hospital cleaning?

There is still a place for many of these products in the healthcare sector and likely to be so for many years to come. Healthcare authorities are under increasing pressure to cut costs and stay safe, whilst still being mindful of the wider environment. Therefore we predict peracetic acid is destined to be the staple disinfectant for at least the near future in hospital cleaning and we are certainly expecting strong growth in the sector.

www.airedalechemical.com