We live in the passive age – passive income, passive aggression, passive cleaning. Wait? Passive cleaning? How’s that possible? A cursory glance along the aisles of any grocery store will reveal the bewildering array of cleaning products – sprays, anti-microbial cloths, scrubs, crèmes, rinses, and more – targeting the not-so-passive germophobe shopper. And this is a big industry. Based on the 2013 United States census(1), there are approximately 242 million adult residents of the US and, with the average consumer spending $504 per annum on cleaning supplies, that equates to an approximate upper limit of $122 billion per annum. And that assumes consumers are actively acquiring, using, and re-purchasing products to maintain cleanliness and safety in their homes.(2) But what if all of this spritzing, scrubbing, and rinsing could be replaced by something a little less strenuous, not to mention prone to human failure. In a recent piece, we reported on the rising use of UV-based cleaner robots in hospital settings but what if we could also leverage tools that work passively in the constant war on germs?
It has long been a tradition that hospital linens – bed sheets, pillowcases, towels, washcloths, and the like – are crisply-laundered, bleached white linens that positively exude an air of comfort. Of being in a safe and trusted place, cared for by professionals. In short, their laundered sterility is a code for ‘You’re in good hands.’ But with the advent of a new technology, the look and feel of hospital bed linens might be about to change. In medical facilities both here in the Unites States and as far afield as the United Kingdom, France and Finland, hospital managers are moving away from cotton and linen and embracing a brand new technology – copper-oxide infused fleece – for their in-patient beds. Following a 2016 healthcare study, one hospital, Sentara CarePlex Hosptial based in Hampton, VA, replaced its linens with a soft, taupe-colored set of sheets, blankets, and pillow cases that not only offer the comforting look of home to patients but also fight off bacteria and dramatically reduce the incidents of hospital-borne infections. And how significant is this passive germ resistance? Let’s take a look at the statistics…
Hospital-acquired infections (HAIs) claim the lives of approximately 75,000 people and cost the country an estimated $9.8 billion per annum. In a ground-breaking meta-analysis published in the JAMA Internal Medicine in 2013, researcher Eyal Zimlichman of Brigham and Women’s Hospital and the Harvard Medical School, Massachusetts, reviewed 26 HAI studies published between 1998 and 2013. Analyzing the top five procedures that resulted in complications – from surgical site infections in the number one spot to catheter-associated urinary tract infections in fifth place – Zimlichman and his colleagues uncovered some phenomenal statistics. Even adjusted for contemporary costs, they found that these A-list HAIs added an average of $45,814 (for CLABIs) and $896 (for CAUTIs – the most inexpensive HAI of the group) per patient, per visit. And in concluding that ‘health care-associated infections represent a major threat to patient safety,’ their report proposed investing in on-going prevention of contamination, as opposed to treating preventable infections.(4)
And this is good news for hospitals, patients, and for the insurance carriers that are assumed to bear the cost. With ‘copper-infused products [contributing] to an 83 percent reduction in some infections and a 78 percent drop in a host of multi-drug resistant strands of bacteria,’ the costs of HAIs drops steeply.(5) In France, for example, one Parisian facility, Rambouillet Hospital, ‘reported a reduction in the acquisition of multi-drug resistant bacteria in intensive care unit patients after the introduction of antimicrobial copper surfaces.’(6) And if the facility is not spending money on post-infection treatments to cure entirely preventable issues, it can – theoretically – allocate the savings to other areas.
And it’s not only bed sheets and towels that benefit from the inherent anti-microbial characteristics of copper. Part of the Helsinki University Hospital in Finland, the Jorvi Hospital claims to be the first to have outfitted all desks and keyboards in its emergency wards, and toilet seats, grab rails, and door handles in the cardiology wards. In a 2014 article published by Cleanroom Technology, Kirsi Skogberg, Hygiene Doctor at HUS Jorvi Hospital, is quoted as saying “We identified the most frequently touched surfaces in our hospital’s emergency unit and bathroom and replaced them with copper surfaces, which seem promising new tools for augmenting existing infection control measures.”(7) Furthermore, a study published in 2016 in the online edition of the American Journal of Infection Control (lead author Shannon Hinsa-Leasure) demonstrated that even when thoroughly cleaned and left unoccupied surfaces in patient rooms quickly re-contaminate with bacterial loads.(8) In the same study at the Grinnell Regional Medical Center in Grinnell, Iowa, it was found that 93% of patient rooms with copper high touch surfaces remained ‘at or near the recommended threshold for terminal cleaning (250 CFU/100 cm2). [Whereas only] 49 percent of rooms without copper surfaces met that same threshold.’(9)
All of which is exciting new technology for hospitals and critical care units but how does this relate to cleanrooms? It’s simple. In addition to the linens and copper-alloy surfaces, the same technology could be made to produce copper-infused gowns for use in contamination-controlled environments, offering a powerful new weapon in the arsenal of those tasked with ensuring sterility within the workplace.
As all cleanroom managers know, it can be a full-time job to ensure that even the most fastidious of employees are conforming perfectly to SOPs and cGMPs in their work environments. With the greatest percentage of contamination being accidentally imported into the cleanroom by personnel, anything that assists in minimizing contamination is helpful. And even when protocol is strictly enforced and followed, sterile environments still face particularly daunting challenges where microbes are concerned. Woven, non-woven, and composite fabrics – that is, exactly the type of fabrics used in clothing and in personal protective equipment – all have the potential to act as contamination vectors, harboring agents that can cause problems in an aseptic environment.
But why are surface treatments insufficient in stemming the tide of microbial infestation? Let’s look a little closer…
Although anti-microbials are very different from one another in terms of their chemical make-up, impact on people and on the environment, durability across a variety of substrates, cost, and the ways in which they interact with other chemicals, they basically all function in one of two ways. Using a combat analogy, when applied to textiles – as in our example – the conventional leaching type of antimicrobial compound engages the enemy – the microbe – as it is transferred from the surface of the treated material. It enters its target and, acting as a toxin, kills it. However, the transfer from substrate to microbe means that it is effectively removed from the battlefield. The second type of anti-microbial is the bound compound – a foot soldier that remains within a cordoned zone – the treated fabric – stabbing and electrocuting the microbe on a molecular level.(10) Repeated use, wear, and laundering of textiles that are treated with leaching-style anti-microbials will result in the deterioration of the compound’s efficacy. And this deterioration – with its weakened payload – brings in its wake the potential to allow the targeted organisms to adapt and resist. Just as with bacteria, microbes that are repeatedly exposed to sub-lethal doses of toxins can become resistant and develop into ‘superstrains.’
So why should the use of copper-infused textiles provide an answer? Copper is an enduring element that will remain perpetually active throughout the fabric’s lifetime and, unlike other anti-microbial compounds, its potency and efficacy remain constant. By its very nature, copper does not allow for hot zones (‘zones of inhibition’) nor for their opposite – areas in which sub-lethal doses could enable microbial growth. It neither leaches nor degrades and, alongside its alloys (brass, bronze, cupronickel, and so on) copper is a natural anti-microbial material that has been utilized – even in the earliest times – to promote public health. From its use by ancient civilizations to store and transport drinking water to its contemporary applications in our 21st century health system, copper is leveraged because of its oligodynamic effect, the biocidal effect some metals exhibit even in low concentrations. First noted in 1893 by Swiss botanist Karl Wilhelm von Nägeli, oligodynamic metals react with certain groups of enzymes and proteins and are thought to work in microbes by rupturing membrane walls, disrupting osmotic pressure, facilitating inappropriate protein-binding, causing oxidative stress, and stealing electrons from lipids which results in cell death.(11) In testing by the Environmental Protection Agency (EPA), bactericidal copper products killed 99.9% of bacteria – including Methicillin-Resistant Staphylococcus aureus (MRSA), E. coli, Enterobacter aerogenes, and Vancomycin-Resistant Enterococcus faecalis (VRE) – within a 2-hour exposure window, even after repeated contamination.
All of which is excellent news for hospitals and medical facilities, but let’s also imagine what it could do for cleanrooms. Within the cleanroom environment, microbial build-up is strictly controlled, but what about when personnel are entering the gowning room? Using an ungloved hand to open the gowning room door enables cross contamination from hand to door handle to clothes and, once within the gowning area, this contamination can be passed on as a technician handles personal protective garments before entering the controlled environment. So what if – in addition to rethinking the composition of personal protective equipment such as gowns, gloves, or hairnets -cleanrooms were to take a leaf out of the hospitals’ playbook? Could an additional step in contamination control be the installation of copper door handles, push plates, locker doors, and dispensers in areas through which an employee must pass on their way to a sterile environment? Granted, there are industries that may shy away from the presence of copper – the semi-conductor industry being a clear example. But for the pharmaceutical industry, biomedical device manufacturers, compounding pharmacies, food and beverage producers, and the automotive industry, the use of copper would present additional benefits that outweigh any adverse effects.
But if copper is in contact with the skin both through routine touch and use in outerwear, is this exposure safe? According to a public health statement issued by the Department of Health and Human Services (Agency for Toxic Substances and Disease Registry), exposure to copper is a concern mainly if it is absorbed into the body by ingestion or inhalation.(12) Those who work in the copper mining industry, for example, may be exposed to copper-containing dust or those whose jobs bring them into contact with soluble copper compounds – electroplating and waste water treatment plants, for instance. But for most cleanroom personnel, daily skin contact with copper door latches or keyboard covers would offer no detrimental effect and might even be healthier than continual exposure to chemically-based anti-microbials. And given the ultra-efficient 99.9% kill rate and low re-colonization rate of this passive contamination control technology it could very well be time our industry embraced copper as the new – and natural – partner in the fight against the microbes.
Would you like to see more copper in your workplace? Do you already use copper-alloys for anti-microbial protection? We’d love to hear your thoughts.