Antimicrobial copper alloy touch surfaces are surfaces that are made from copperorcopper alloys. The phrase "touch surfaces" means all the various kinds of surfaces (such as door knobs, railings, tray tables, etc.) that are often touched by people at work or in everyday life, especially (for example) in hospitals and clinics.
Touch surfaces that are in frequent use today and that are not made with copper alloys can easily accumulate a variety of harmful microbes (viruses, bacteria, etc.). These microbes can often survive on touch surfaces for surprisingly long periods of time (e.g., for more than 30 days on some popular materials). However, copper and copper alloys have a natural ability to destroy harmful microbes relatively rapidly - often within two hours or less (i.e. copper alloy surfaces are antimicrobial).
This natural ability of copper alloys to destroy a wide range of microbes deposited on the alloys’ surfaces has been proven by an extensive body of research. The research also suggests that if touch surfaces are made with copper alloys, the reduced or totally destroyed microbial populations on the antimicrobial alloys will ultimately reduce the incidence of transmission of disease-causing organisms.
Two hundred and eighty two different copper alloys were recently granted registrations by the United States Environmental Protection Agency (EPA)’s Office of Pesticide Programs. Product manufacturers are now permitted to make antimicrobial claims with public health benefits on products made with these alloys. A wide variety of EPA-registered copper alloy products are now being introduced in buildings and environments where they have the potential to reduce the spread of diseases due to surfaces contaminated by infectious microbes.
Copper alloy surfaces have intrinsic properties to destroy a wide range of microorganisms. In the interest of protecting public health, especially in heathcare environments with their susceptible patient populations, an abundance of peer-reviewed antimicrobial efficacy studies have been conducted regarding copper’s efficacy to destroy E. coli O157:H7, methicillin-resistant Staphylococcus aureus (MRSA), Staphylococcus, Clostridium difficile, influenza A virus, adenovirus, and fungi.[1]. These studies plus others directed by the United States Environmental Protection Agency, resulted in the registrations of 282 different copper alloys as certified antimicrobial materials that have public health benefits. For further information about the antimicrobial efficacy studies of copper alloys, see: Antimicrobial efficacy of copper alloy touch surfaces.
On February 29, 2008, the United States Environmental Protection Agency (EPA) approved the registrations of five different groups of copper alloys as “antimicrobial materials.” [2] The EPA registrations covered 275 different compositions of copper alloys within these groups. An additional seven copper alloys in a sixth group were approved on July 12, 2009. All of the alloys have minimum nominal copper concentrations of 60%. The results of the EPA-supervised antimicrobial studies, demonstrating copper's strong antimicrobial efficiacies across a wide range of alloys, were recently published.[3]
These copper alloys are the only solid surface materials to be granted “antimicrobial public health claims” status by EPA. Before these registrations were granted, only antimicrobial gases, liquids, sprays, and concentrated powders, including sterilizers, disinfectants and antiseptics, were registered to make antimicrobial public health claims.
The bacteria destroyed by copper alloys in the EPA-supervised antimicrobial efficacy tests include:
The registrations are based on studies supervised by EPA which found that copper alloys kill more than 99.9% of disease-causing bacteria within just two hours when cleaned regularly (i.e., the metals are free of dirt or grime that may impede the bacteria’s contact with the copper surface).
To attain the EPA registrations, the copper alloy groups had to demonstrate strong antimicrobial efficacies according to all of the following rigorous tests:
The alloy groups tested and approved were C11000, C51000, C70600, C26000, C75200, and C28000.
The EPA registration numbers for the six groups of alloys are as follows:[7]
| Group | Copper % | EPA Registration Number |
|---|---|---|
| I | 95.2 to 99.99 | 82012-1 |
| II | 87.3 to 95.0 | 82012-2 |
| III | 78.1 to 87.09 | 82012-3 |
| IV | 68.2 to 77.5 | 82012-4 |
| V | 65.0 to 67.8 | 82012-5 |
| VI | 60.0 to 64.5 | 82012-6 |
The following claims are now legally permitted when marketing EPA-registered antimicrobial copper alloys in the USA:
Laboratory testing has shown that when cleaned regularly:
- Antimicrobial Copper Alloys continuously reduce bacterial contamination, achieving 99.9% reduction within two hours of exposure.
- Antimicrobial Copper Alloy surfaces kill greater than 99.9% of Gram-negative and Gram-positive bacteria within two hours of exposure.
- Antimicrobial Copper Alloy surfaces deliver continuous and ongoing antibacterial action, remaining effective in killing greater than 99% of bacteria within two hours.
- Antimicrobial Copper Alloys surfaces kill greater than 99.9% of bacteria within two hours, and continue to kill 99% of bacteria even after repeated contamination.
- Antimicrobial Copper Alloys surfaces help inhibit the buildup and growth of bacteria within two hours of exposure between routine cleaning and sanitizing steps.
- Testing demonstrates effective antibacterial activity against Staphylococcus aureus, Enterobacter aerogenes, Methicillin-resistant Staphylococcus aureus (MRSA), Escherichia coli O157:H7, and Pseudomonas aeruginosa
The registrations state that “antimicrobial copper alloys may be used in hospitals, other healthcare facilities, and various public, commercial and residential buildings.”
The EPA copper alloy registrations were granted “with public health claims,” meaning that they permit manufacturers of copper-based products sold in the U.S. to claim on their labels the ability of copper, brass, and bronze to kill harmful, potentially deadly bacteria.
As a condition of registration established by EPA, the Copper Development Association (CDA) in the USA is responsible for the product stewardship of antimicrobial copper alloy products. CDA must ensure that manufacturers promote these products in an appropriate manner. Manufacturers must only promote the proper use and care of these products and must specifically emphasize that the use of these products is a supplement and not a substitute to routine hygienic practices.
EPA mandated that all advertising and marketing materials for antimicrobial copper products contain the following statement:
The use of a Copper Alloy surface is a supplement to and not a substitute for standard infection control practices; users must continue to follow all current infection control practices, including those practices related to cleaning and disinfection of environmental surfaces. The Copper Alloy surface material has been shown to reduce microbial contamination, but it does not necessarily prevent cross-contamination.
Antimicrobial copper alloys are intended to provide supplemental antimicrobial action in between routine cleaning of environmental or touch surfaces in healthcare settings, as well as in public buildings and the home. Users must also understand that in order for antimicrobial copper alloys to remain effective, they cannot be coated in any way.
CDA is currently implementing an outreach program through written communications, a product stewardship website [8], and through a Working Group which meets periodically to expand educational efforts.
More than 100 different potential product applications were cited in the registrations for their potential public health benefits.
The following products have been approved for EPA-Registrered antimicrobial copper alloy touch surfaces.
The following copper alloy surface products have been granted antimicrobial registration status with public health claims by EPA for healthcare facilities:
The following copper alloy surface products have been granted antimicrobial registration status with public health claims by EPA for public community facilities:
Residential buildings include homes, apartments, apartment buildings and other kinds of residences. The following copper alloy surface products have been granted antimicrobial registration status with public health claims by EPA for residential buildings:
The following copper alloy surface products have been granted antimicrobial registration status with public health claims by EPA for mass transit facilities:
The following copper alloy surface products have been granted antimicrobial registration status with public health claims by EPA for various products:
The EPA warranty statement is worded as follows:
If used as intended, ANTIMICROBIAL COPPER ALLOYS are wear-resistant and the durable antibacterial properties will remain effective for as long as the product remains in place and is used as directed.
Note: With the exception of the product name and the percentage of active ingredient, the EPA-approved Master Labels for the six groups of registered alloys are identical.
Microorganisms are known to survive on inanimate ‘touch’ surfaces for extended periods of time.[9] This can be especially troublesome in hospital environments where patients with immunodeficiencies are at enhanced risk for contracting nosocomial infections (hospital-borne infections), often with fatal consequences.
Touch surfaces commonly found in hospital intensive care unit (ICU) rooms, such as bed rails, call buttons, touch plates, and chairs, are known to be contaminated with high levels of potentially dangerous bacteria, including Staphylococcus, Methicillin-resistant Staphylococcus aureus (MRSA), one of the most virulent strains of antibiotic-resistant bacteria) and the Vancomycin-resistant Enterococcus (VRE) [10]. Objects in closest proximity to patients have the highest levels of staphylococcus, MRSA, and VRE. This is why touch surfaces in ICU rooms can serve as abundant sources, or reservoirs, for the spread of bacteria from the hands of healthcare workers and visitors to patients.
Independent laboratory studies conducted on behalf of the United States Environmental Protection Agency [11] (EPA) have shown that copper, brass, and bronze are more than 99.9% effective in killing specific disease-causing bacteria, including MRSA. The efficacy of copper alloys to destroy bacteria prompted EPA to register copper, brass, and bronze as antimicrobial materials. Manufacturers of registered antimicrobial copper alloy hospital products are now permitted to make public health claims regarding the germicidal properties and benefits of their products.
Clinical trials are now being conducted at one of the world’s most prestigious cancer facilities, the Memorial Sloan-Kettering Cancer Center in New York City, as well as at the Medical University of South Carolina in Charleston, and the Ralph H. Johnson VA Medical Center in Charleston, South Carolina to compare bio-loads found on stainless steel, plastic, aluminum, and copper alloy objects in hospital intensive care units. This study is being undertaken to determine whether copper alloys can reduce the incidence of cross contamination and whether copper alloys can lower rates of hospital-borne infections. The trials are being funded by the United States Department of Defense (DOD) under the aegis of the Telemedicine and Advanced Technologies Research Center (TATRC), a section of the United States Army Medical Research and Materiel Command (USAMRMC).[12]
DOD has extraordinary interests in the potential for antimicrobial copper surfaces to reduce hospital-acquired infections because it wants to prevent hospital-acquired infections among thousands of its enlisted armed forces servicemen and servicewomen who have been injured in recent conflicts. TATRC, which funds a Military Infectious Disease Program [13], has been granted funds by the United States Congress to evaluate the antimicrobial effectiveness of copper, brass and bronze alloys. The studies are coordinated through the Advanced Technology Institute in Charleston, South Carolina. Two five-year federal research programs were launched in 2006.
The first pilot study to assess the efficacy of copper to reduce microbial burden associated with objects in the patient care environment was recently completed at the Medical University of South Carolina;[14] The study found that continuous antimicrobial activities of copper alloys are very effective in reducing total microbial burdens in patient rooms at the hospital’s intensive care unit (ICU) and on individual objects within those rooms. Microbial activity on these surfaces was reduced by an average of 87.4%. Extraordinary microbial burden reductions were observed on copper bed rails (99% microbial burden reduction) and on call buttons (90% microbial burden reduction). Surfaces of these two products are very important vehicles for microbial loading: they account for 85.3% of the total microbial burden of rooms that were not retrofitted with copper touch surfaces.
Copper was also found to reduce the microbial burden of IV poles by 67%. Loadings in chair arms retrofitted with copper surfaces were reduced by 38%.
Staphylococcus was the predominant organism isolated from each of the objects in the study. MRSA and VRE were frequently isolated from non-copper objects but they were never isolated from copper alloy objects. The copper alloys completely destroyed MRSA and VRE, microorganisms that are frequently responsible for potentially fatal patient infections.
A similar clinical trial is currently underway at Selly Oak Hospital, University Hospital Birmingham, in the United Kingdom. Results from this trial indicate a 90-95% reduction in contamination on copper alloy surfaces at a ward retrofitted with copper alloy materials when compared to a control ward without touch surfaces made from antimicrobial copper alloys.[15]
In 2005, antimicrobial studies in healthcare environments were conducted at the Dermatology Ward and in the Neonatal Intensive Care Unit (NICU) at Kitasato University Hospital in Japan. Researchers evaluated the antimicrobial efficacy of copper on floors, sinks, push plates, showerheads and doorknobs by comparing bacterial loads on these surfaces and on their non-copper counterparts. The results demonstrated that copper and copper alloys have a strong antimicrobial effect while non-copper materials currently used for these surfaces do not.[16]
Other hospital trials evaluating the antimicrobial efficacy of copper and copper alloys are underway in Germany, Chile and South Africa.[17] It is anticipated that these trials will continue to demonstrate that using copper alloy touch surfaces is an effective supplement to infection control programs in healthcare facilities. Updates from these clinical trials will be presented here as published results become available.
