Peer-reviewed research papers discussing the antimicrobial property of copper-based metals with clarifying statements*.
-
Dr. Anton Shufutinsky, Harold Michels, Wilton Moran, Adam Estelle, James Michel, Chris Dreska, Dennis Simon. Poster presented at 2011 US Armed Forces Public Health Conference.
Summary:
Explains the potential application of Antimicrobial Copper
surfaces as a method for preventing surface and airborne microbial
contamination in military healthcare facilities, food handling
operations, and other occupational settings.
Clarification:
The efficacy of Antimicrobial Copper against Influenza A has not
been proven by U.S. EPA-sanctioned testing. No claim of
antimicrobial effectiveness is made, either expressed or implied,
with regard to Influenza A. Clinical trial results are
preliminary and under review; claims related to clinical trials
have not been approved or reviewed by U.S. EPA."
Click below PDF link to view poster in
its entirety.
View [PDF 1323 kB]
-
J. O. Noyce, H. Michels and C.W. Keevil, Applied and Environmental Microbiology, p. 2748 - 2750, Vol. 73, No. 8, April 2007
Summary:
Uses fluorescent microscopy to compare viability of Influenza A
on copper and stainless steel. Copper showed a 4-log reduction
after 6 hours while steel only showed a 1-log reduction after 24
hours.
Clarification:
The efficacy of Antimicrobial Copper against Influenza A has not
been proven by U.S. EPA-sanctioned testing. No claim of
antimicrobial effectiveness is made, either expressed or implied,
with regard to Influenza A.
-
H.T. Michels, D.G. Anderson, J.O. Noyce, S.A. Wilks and C.W. Keevil, Proceedings of the Sixth International Copper-Cobre Conference, p. 121-133, Vol. I, August 2007
Summary:
Describes potential healthcare applications and barriers for
antimicrobial copper alloys. Authors review efficacy data against
various organisms and EPA testing.
Clarification:
The efficacy of Antimicrobial Copper against Listeria
monocytogenes has not been proven by U.S. EPA-sanctioned
testing. No claim of antimicrobial effectiveness is made, either
expressed or implied, with regard to Listeria
monocytogenes. Additionally, Antimicrobial Copper surfaces are
not approved for use in direct food-contact applications.
-
J. O. Noyce, H. Michels and C. W. Keevil, Journal of Hospital Infection, Vol. 63, Issue 3, p. 289-297, July 2006
Summary:
Demonstrates copper's ability to kill epidemic
Methicillin-resistant Staphylococcus aureus under
different conditions in comparison to stainless steel. Illustrates
effects of bacteria concentration, temperature and copper content
on antimicrobial efficacy
Clarification:
Antimicrobial Copper surfaces have been proven to kill 99.9% of
certain bacteria* within two hours. No claim of antimicrobial
effectiveness in less time is made, either expressed or
implied.
-
S. A. Wilks, H. T. Michels and C. W. Keevil, International Journal of Food Microbiology, 111, September (2006), p. 93-98.
Summary:
Compares the viability of Listeria monocytogenes on
various copper alloys and stainless steel. Copper-based alloys
produced a significant reduction in viability compared to stainless
steel. Suggests materials selection could impact bioload in various
environments.
Clarification:
The efficacy of Antimicrobial Copper against Listeria
monocytogenes and Desulfovibrio desulfuricans has not
been proven by U.S. EPA-sanctioned testing. No claim of
antimicrobial effectiveness is made, either expressed or implied,
with regard to Listeria monocytogenes or Desulfovibrio
desulfuricans. Additionally, copper alloy surfaces are not
approved for use in direct food-contact applications.
-
H. T. Michels and D. G. Anderson, pp 185-190, Metal Ions in Biology and Medicine: Vol. 10., Eds Ph. Collery, I. Maymard, T. Theophanides, L. Khassanova, T. Collery. John Libbey Eurotext, Paris © 2008
Summary:
Discusses potential impact of antimicrobial copper alloys on
amount of certain bacteria on frequently touched surfaces in
healthcare settings. Describes the steps required to make public
health claims and summarizes EPA test protocols and results.
Clarification:
The efficacy of Antimicrobial Copper against Influenza A has not
been proven by U.S. EPA-sanctioned testing. No claim of
antimicrobial effectiveness is made, either expressed or implied,
with regard to Influenza A. Additionally, Antimicrobial Copper
surfaces are not approved for use in direct food-contact
applications.
-
H. T. Michels, J. O. Noyce, and C. W. Keevil, Letters in Applied Microbiology, 49 (2009) 191-195
Summary:
Demonstrates that commercially available silver ion-containing
coatings marketed as antimicrobial do not exhibit any meaningful
reduction of MRSA under typical indoor conditions. Copper alloys
exhibited antimicrobial efficacy under all tested conditions. Download the full
redacted text here.
Clarification:
This article has been redacted to be consistent with the U.S.
EPA-approved antimicrobial product registration for Antimicrobial
Copper alloys. U.S. EPA-approved testing demonstrates that
Antimicrobial Copper alloys, when cleaned regularly, kill 99.9% of
certain bacteria* (*see article) within two hours. Copper alloys
have been shown to reduce microbial contamination, but not to
prevent cross contamination, and are a supplement to, not a
substitute for, good hygienic practices. Users must follow routine
cleaning and disinfection practices.
-
L. Weaver, H. T. Michels, and C. W. Keevil, Journal of Hospital Infection, Vol. 68, Issue 2, p. 145-151, February 2008
Summary:
Compares the viability of Clostridium difficile on
copper and stainless steel. Reports a significant reduction of
Clostridium difficile was observed on alloys with >70%
copper content while no reduction is observed on steel. Suggests
use of copper alloys in hospitals may reduce the levels of
Clostridium difficile on frequently touched surfaces.
Clarification:
The efficacy of Antimicrobial Copper against Clostridium
difficile has not been proven by U.S. EPA-sanctioned testing.
No claim of antimicrobial effectiveness is made, either expressed
or implied, with regard to Clostridium difficile.
-
H. Michels, W. Moran and J. Michel, International Journal of Metalcasting, Summer 08, pp 47-56, 2008
Summary:
Discusses the antimicrobial properties of copper alloys and
their potential to reduce the amount of certain bacteria on
frequently touched surfaces. Efficacy data address other materials
and the effects of tarnishing, bacteria concentration and repeated
contamination. EPA testing, results and registration are
highlighted.
Clarification:
The efficacy of Antimicrobial Copper against Influenza A has not
been proven by U.S. EPA-sanctioned testing. No claim of
antimicrobial effectiveness is made, either express or implied,
with regard to Influenza A. Additionally, Antimicrobial Copper
surfaces are not approved for use in direct food-contact
applications. Antimicrobial copper alloy surfaces have been shown
to reduce microbial contamination, but not necessarily prevent
cross contamination.
-
S. Mehtar, I. Wiid, and S.D. Todorov
Journal of Hospital Infection, Vol. 68, Issue 1, p 45-51, January 2008
Summary:
Compares the viability of MRSA, Klebsiella pneumonia,
Pseudomonas aeruginosa, Acinetobacter baumannii,
Candida albicans and Mycobacterium tuberculosis on copper
alloys, stainless steel and PVC. Results illustrate copper's
ability to kill pathogens most commonly associated with
hospital-acquired infections. No effect was observed on PVC and
stainless steel.
Clarification:
The efficacy of Antimicrobial Copper against Klebsiella
pneumonia, Acinetobacter baumanii, Candida albicans,
Mycobacterium tuberculosis, and Campylobacter jejuni has
not been proven by U.S. EPA-approved testing. No claim of
antimicrobial effectiveness is made, either expressed or implied,
with regard to Klebsiella pneumonia, Acinetobacter baumanii,
Candida albicans, Mycobacterium tuberculosis, and
Campylobacter jejuni. Copper materials have been proven to
kill 99.9% of certain bacteria* within two hours. No claim of
antimicrobial effectiveness in less time is made, either expressed
or implied.
-
H. T. Michels, S. A. Wilks and C. W. Keevil, Proceedings of Copper 2003 - Cobre 2003, The 5th International Conference, November 30-December 2, 2003, Santiago, Chile, Vol. 1 - Plenary Lectures, Economics and Applications of Copper, pp. 439-450, A Publication of The Canadian Institute of Mining, Metallurgy and Petroleum, Montreal, Quebec, Canada, 2003
Summary:
Investigates the viability of E. coli O157:H7 on 25
copper alloy surfaces at 20C and 4C (refrigeration temperature).
Bacteria reduction occurred with all alloys and was faster at the
higher temperature and on alloys containing higher levels of
copper. Further research is recommended to determine copper's
effect on molds and other organisms that cause respiratory
infections.
Clarification:
The efficacy of Antimicrobial Copper against Listeria
monocytogenes, or molds has not been proven by U.S.
EPA-approved testing. No claim of antimicrobial effectiveness is
made, either expressed or implied, with regard to Listeria
monocytogenes or molds. Additionally, Antimicrobial Copper
surfaces are not approved for use in direct food-contact
applications.
-
P. J. Kuhn, Diagnostic Medicine, 1983.
Summary:
Discusses the unique bactericidal properties of copper and brass
compared to stainless steel and aluminum against various organisms.
Results suggest that hospitals should utilize brass (copper alloy)
hardware to minimize bacterial growth on these surfaces.
Clarification:
References to effectiveness against Streptococcus have
not been proven by U.S. EPA-sanctioned testing. No claim of
antimicrobial effectiveness is made, either expressed or implied,
with regard to this organism. Antimicrobial Copper surfaces have
been proven to kill 99.9% of certain bacteria* within two hours. No
claim of antimicrobial effectiveness in less time is made, either
expressed or implied.
-
H. T. Michels, ASTM Standardization News, October 2006.
Summary:
Article provides an overview on the antimicrobial characteristic
of copper. Describes the research performed to date and the
potential applications of antimicrobial copper products. Includes a
letter from the editor which highlights the article.
Clarification:
References to effectiveness against Streptococcus,
Influenza A, and Listeria monocytogenes have not been
proven by U.S. EPA-sanctioned testing. No claim of antimicrobial
effectiveness is made, either expressed or implied, with regard to
these organisms. Additionally, Antimicrobial Copper surfaces are
not approved for use in direct food-contact applications.
Antimicrobial Copper surfaces have been proven to kill 99.9% of
certain bacteria* within two hours. No claim of antimicrobial
effectiveness in less time is made, either expressed or implied.
Antimicrobial Copper surfaces have been shown to reduce microbial
contamination, but they do not necessarily prevent cross
contamination.
-
H. T. Michels, S. A. Wilks and C. W. Keevil. The Second Global Congress Dedicated to Hygienic Coatings & Surfaces, Orlando, Florida, USA, 26-28 January, 2004, Paper 16, Published by Paint Research Association, Middlesex, UK, ISBN 0-9543164-5-2, 2004.
Summary:
Tests the viability of E. coli O157:H7 on a variety of
copper alloy surfaces. All tested copper alloys rendered the
bacteria nonviable after several hours. E. coli O157:H7 has been
responsible for a number of food recalls and can survive on
stainless steel for days. Results suggest copper alloys will be
useful beyond food processing applications.
Clarification:
The efficacy of Antimicrobial Copper against Listeria
monocytogenes has not been proven by U.S. EPA-approved
testing. No claim of antimicrobial effectiveness is made, either
expressed or implied, with regard to Listeria
monocytogenes. Additionally, copper alloy surfaces are not
approved for use in direct food-contact applications.
-
S. A. Wilks, H. Michels and C. W. Keevil, International Journal of Food Microbiology, 105 (2005), p. 445-454.
Summary:
Compares the survivability of an infectious strain of
Escherichia coli on copper alloys and stainless steel.
Copper alloys exhibited a large reduction within several hours
while stainless steel did not. Addresses the advantages of alloying
and suggests using antimicrobial surfaces in environments where
bacterial contamination is a concern.
Clarification:
The efficacy of Antimicrobial Copper against Legionella
pneumophilia has not been proven by U.S. EPA-sanctioned
testing. No claim of antimicrobial effectiveness is made, either
expressed or implied, with regard to Legionella
pneumophilia. Additionally, Antimicrobial Copper surfaces are
not approved for use in direct food-contact applications.
-
J. O. Noyce, H. Michels, and C. W. Keevil, Applied and Environmental Microbiology, p. 4239-4244, June 2006.
Summary:
Investigates ability of copper to kill Escherichia coli
O157:H7 which is responsible for diseases caused by food
contamination. Incorporates beef juice with bacteria to simulate
food cross contamination scenario. High copper containing alloys
greatly reduced the amount of E. coli O157:H7 at room
(22C) and low temperatures (4C). Stainless steel, the control, had
no effect.
Clarification:
Antimicrobial Copper surfaces are not approved for use in direct
food-contact applications. Antimicrobial Copper surface materials
have been shown to reduce microbial contamination, but they do not
necessarily prevent cross contamination.
-
H. T. Michels. Plumbing Standards-An Official Publication of the American Society of Sanitary Engineers, October-December, 2004
Summary:
Reviews numerous studies and papers that illustrate copper's
ability to kill a variety of organisms known to cause infection.
Emphasis is placed on Legionella pneumophila which is
transferred through piping systems (i.e. HVAC, water delivery) and
has caused a number of pneumonia outbreaks. Results suggest copper
can reduce the levels of harmful pathogens in plumbing
networks.
Clarification:
The efficacy of Antimicrobial Copper against Legionella
pneumophilia has not been proven by U.S. EPA-approved testing.
No claim of antimicrobial effectiveness is made, either expressed
or implied, with regard to Legionella pneumophilia.
Additionally, copper alloy surfaces are not approved for
applications in direct contact with stagnant water or for water
transport.
-
H. T. Michels, J. P. Noyce, S. A. Wilks and C. W. Keevil. Copper for the 21st Century, Materials Science & Technology 2005 (MS&T’05) Conference, Pittsburgh, PA, September 25-28, 2005, ASM, ACerS, AIST, AWS, TMS, ISSN: 1546-2498
Summary:
Illustrates the ability of copper alloys to kill several food
borne pathogens known to cause infection. Also demonstrates
efficacy against Methicillin-resistant Staphylococcus
aureus which is largely responsible for hospital acquired
infections. Stainless steel, the control, had no effect on any of
the pathogens. Results suggest copper alloys may reduce the levels
of infectious pathogens on surfaces in contact with food and
touched by humans.
Clarification:
Any references in this article that state or imply effectiveness
in controlling disease or the transmission of bacteria that can
cause disease in humans have not been approved by the U.S. EPA or
FDA. The conclusions reached in this article are solely the
opinions of the researchers and authors. Antimicrobial Copper
alloys cannot make "disease control" claims and U.S. EPA-approved
testing only supports claims of antimicrobial effectiveness against
specific bacteria that are associated with disease. The
antimicrobial effectiveness of Antimicrobial Copper against
Listeria monocytogenes, Influenza A, and Aspergillus
niger has not been proven by U.S. EPA-sanctioned testing. No
claim of antimicrobial effectiveness is made, either expressed or
implied, with regard to Listeria monocytogenes, Influenza
A, or Aspergillus niger. Additionally, Antimicrobial
Copper surfaces are not approved for use in direct food-contact
applications.
-
The articles above include conclusions about Antimicrobial Copper that do not reflect EPA product registration approvals. The conclusions reached in these articles are the opinions of the researchers and authors.
The below legal disclaimer is applicable to all above published
articles and publications
*U.S. EPA-approved testing demonstrates efficacy of Antimicrobial Copper surfaces against only the following organisms: Staphylococcus aureus, Enterobacter aerogenes, Escherichia coli O157:H7, Pseudomonas aeruginosa, Methicillin-resistant Staphylococcus aureus (MRSA), and Vancomycin-Resistant Enterococcus faecalis (VRE). Any reference to effectiveness against other organisms has not been proven by U.S. EPA-approved testing. No claim of antimicrobial effectiveness is made, either express or implied, with regard to organisms other than those identified above. Further, any references that state or imply effectiveness in controlling disease or the transmission of bacteria that can cause disease in humans have not been approved by the U.S. EPA or FDA. Antimicrobial Copper surfaces cannot make “infectious disease control” claims. Antimicrobial Copper surfaces have been shown to reduce microbial contamination, but they do not necessarily prevent cross contamination.