# Why isn't copper used for surfaces in hospitals?

## Summary:

copper kills viruses and mircorobes

## Main Question or Discussion Point

If copper kills corona how come we've not spend money on putting it in hospital's etc ? How effective is it would silver be more effective?Our a combination of the both copper disc and a silver disc ?

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berkeman
Mentor
Summary:: copper kills viruses and mircorobes

If copper kills corona how come we've not spend money on putting it in hospital's etc ? How effective is it would silver be more effective?Our a combination of the both copper disc and a silver disc ?
In hospitals we spend a lot of time and effort to disinfect surfaces (with disinfectant wipedowns and UV robots and other methods). And the staff "foam in and foam out" of all rooms and areas to help to minimize any transmission of virus/bacteria between rooms and areas of the hospital. Changing the surfaces to much more expensive materials probably would have minimal impact on disease transmission in places where folks are so diligent about disinfection already.

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pinball1970 and BillTre
BillTre
Gold Member
Copper will corrode over time unless maintained (costs $and labor). The corroded product will probably not be so active at killing stuff. Stainless steel, the common metal alternative for some surfaces, requires way less maintenance. pinball1970, russ_watters, Klystron and 1 other person Copper will corrode over time unless maintained (costs$ and labor).
The corroded product will probably not be so active at killing stuff.

Stainless steel, the common metal alternative for some surfaces, requires way less maintenance.
How long does it take to corrode and what maintenance does it need?

BillTre
Gold Member
Astronuc and phinds
What about in area's(not hospital's) where there is no or little diligence ?
thank you

In hospitals we spend a lot of time and effort to disinfect surfaces (with disinfectant wipedowns and UV robots and other methods). And the staff "foam in and foam out" of all rooms and areas to help to minimize any transmission of virus/bacteria between rooms and areas of the hospital. Changing the surfaces to much more expensive materials probably would have minimal impact on disease transmission in places where folks are so diligent about disinfection already.
couldn't it used in area's where diligence is low to keep viruses under control ?

berkeman
Mentor
couldn't it used in area's where diligence is low to keep viruses under control ?
Low diligence is not allowed in quality hospitals. That would get the patients very sick and get the medical folks who are responsible fired.

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berkeman
Mentor
What about in area's(not hospital's) where there is no or little diligence ?
couldn't it used in area's where diligence is low to keep viruses under control ?
Maybe you are referring to areas in the third world or other economically disadvantaged areas? Could you please list some of the areas that you are thinking of? Thanks.

One of the main situations that I work and train is in areas of "austere medicine", like in areas that have suffered disasters and do not have their normal medical infrastructure intact. We often run out of supplies and have to innovate and re-use supplies, and normal disinfection protocols are challenged. It's similar to what almost has happened with PPE shortages in Emergency Departments and in EMS in the field with the pandemic.

But the solution that you are proposing is not practical, IMO, since it is expensive to install and maintain (the maintenance protocol needed to keep the copper surfaces clean is probably close to the level of the normal disinfection protocols that we already follow).

It's good to ask questions like this, but it would probably help you to volunteer at some emergency medical facilities where you live so that you start to get an appreciation for the protocols that we have in place, and how sincere and careful we are in following them (even in the rain, in the middle of the night, in a tent, with a bloody patient in your hands)...

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BillTre, hutchphd and Keith_McClary
Maybe you are referring to areas in the third world or other economically disadvantaged areas? Could you please list some of the areas that you are thinking of? Thanks.

One of the main situations that I work and train is in areas of "austere medicine", like in areas that have suffered disasters and do not have their normal medical infrastructure intact. We often run out of supplies and have to innovate and re-use supplies, and normal disinfection protocols are challenged. It's similar to what almost has happened with PPE shortages in Emergency Departments and in EMS in the field with the pandemic.

But the solution that you are proposing is not practical, IMO, since it is expensive to install and maintain (the maintenance protocol needed to keep the copper surfaces clean is probably close to the level of the normal disinfection protocols that we already follow).

It's good to ask questions like this, but it would probably help you to volunteer at some emergency medical facilities where you live so that you start to get an appreciation for the protocols that we have in place, and how sincere and careful we are in following them (even in the rain, in the middle of the night, in a tent, with a bloody patient in your hands)...
I work in an industry where I think this could help just wondered how effect it would be? I completely understand the hospital scenario was wrong. How would it work with cash based business ?

Staff Emeritus
2019 Award
How will this help? If the labor needed to maintain copper in hospitals is comparable to the labor required to disinfect, why do you think it will require less effort in a retail store? And if it's less effort to disinfect, why not do just that - do something more effective than copper?

BillTre
Copper-bearing paint used to be popular for painting the bottom of boats because the copper inhibits growth of marine organisms (barnacles etc.). AFAIK, the copper paint is banned now for environmental reasons.

How about the copper water pipe in domestic plumbing? I don't know if that came to popularity because it keeps the water sanitary or if it was ease of installation. Maybe both?

Cost.

As @BillTre said, Copper alone isn't environmentally stable. So you may need a better alloy, BeCu comes to mind (from my electronics world), but that is way too expensive to cover every surface with. There are hospitals that are experimenting with these solutions for high touch surfaces, like bed rails.

Plus, prior to now, lack of knowledge. Big institutions and complex facilities are hard to change quickly.

If you want to know more, I would highly recommend listening to this podcast:

https://www.microbe.tv/twim/55-in-the-copper-room/

They also have links to some good papers on the subject.

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BillTre, berkeman and Lnewqban
DaveC426913
Gold Member
BTW, copper is also malleable and easily marked. It would not take long before it got so many scratches in it that it couldn't effectively be cleaned - and then it would become a liability rather than an asset.

Laroxe, berkeman and Lnewqban
BillTre
Gold Member
Where I live (in Eugene, Oregon) copper pipes are preferred over galvanized because their insides don't rust out (which the pipes in my house are doing). The inside of the copper pipes get a thin layer of chemicals, but then don't seem to be much more effected.

Summary:: copper kills viruses and mircorobes

How effective is it would silver be more effective?
Copper and silver both has very 'mild' anti-bacterial (anti-viral) properties: compared to any real disinfectants, they are just not effective and fast enough. The reason why they got their fame is that they looks nice and are so weak that they could be used without much restrain => doorknobs an cutlery.

At the beginning of XX. century silver was still considered a possibly useful antibiotics in medicine, but it could not hold a candle to real antibiotics invented not much later so it just vanished (later it was re-invented in alternative medicine).

By the way, copper is poisonous. In theory, silver is poisonous too - it is just silver poisoning is actually more stupid than dangerous.

256bits
Gold Member
The corroded product will probably not be so active at killing stuff.
Copper and silver both has very 'mild' anti-bacterial (anti-viral) properties: compared to any real disinfectants,
A study on metal surfaces - stainless steel, pure copper, and a few alloys
https://aem.asm.org/content/81/3/1085 ( 2014 )
A previous study in our laboratory observed that dry copper and copper alloy surfaces rapidly inactivated MNV-1 and destroyed the viral genome. In this new study, we have observed that a relatively small change in the percentage of copper, between 70 and 80% in copper nickels and 60 and 70% in brasses, had a significant influence on the ability of the alloy to inactivate norovirus ..... We have previously shown with a small range of copper alloys the rapid destruction of murine norovirus (MNV), a close surrogate for the human norovirus causing gastrointestinal disease, which is necessary because of the lack of a suitable infectivity assay for the human norovirus
Norovirus had the ability such that most cleaning agents are ineffective against it, and can be viable for up to weeks a wide range of common surfaces.

Depending upon the copper alloy it would seem, and the corrosive species.
After 30 minute contact, a surface of pure copper was effective in destruction , with "efficacy of these brasses in inactivating norovirus is directly proportional to the copper content".

FIG 4
Persistence of MNV infectivity on brasses. Approximately 5 × 105 PFU of infectious virus was applied to 1-cm2 samples of test surfaces and incubated at room temperature. At various time points, virus was removed from the surfaces and assessed for infectious virus by plaque assay as described in the text. The efficacy of these brasses in inactivating norovirus is directly proportional to the copper content; 100% Zn appeared to have some antiviral activity, similar to that of Muntz metal (C28000). The possible antiviral effect of zinc is discussed in the text.
The appearances of these alloys are very different: C72500 is very shiny and polished compared to the dull alloy C70600. This may be due to a passivating oxide layer, which may contribute to efficacy (this alloy is employed in marine engineering because of excellent antifouling properties). Hans et al. (24) reported that a layer of cuprous oxide (Cu2O) was as effective at killing Enterococcus hirae as pure copper but found that copper II oxide, CuO, is inhibitory by forming a protective layer that reduces the rate of corrosion (passivation layer). We observed that if the surfaces of alloys C70600 and C72500 were abraded by rubbing with coarse sandpaper (Fig. 3A), the efficacy of the former to inactivate MNV-1 was reduced following 30 min of contact at room temperature (Fig. 3B). This suggests that the presence of an oxide layer on this alloy contributes to its antiviral efficacy.
Note: I find it difficult to correlate this prose with the suggested figure 3B, regarding ally C72500. ie CuO and Cu2O corrosion, abrasion of the surface, and efficacy of the metal surface.

Although the reference 24 Abstract does suggest that the oxide Cu2O, that forms under normal conditions is as effective as a pure copper surface, with a CuO surface not as effective as either.
CuO was found to significantly inhibit contact killing, compared to pure copper. In contrast, thermally generated Cu2O was essentially as effective in contact killing as pure copper. Copper ion release from the different surfaces roughly correlated with their antibacterial efficacy and was highest for pure copper, followed by Cu2O and CuO. Tris-Cl induced a 10-50-fold faster copper ion release compared to PBS. Since the Cu2O that primarily forms on copper under ambient conditions is as active in contact killing as pure copper, antimicrobial objects will retain their antimicrobial properties even after oxide formation

jackwhirl
After 30 minute contact...
As far as I know for hospital grade disinfectants the required 'kill time' typically measured in seconds, but at (very) few minutes at most and any surface where the stuff is applicable included.

30 minutes to kill, and you can touch it with bare hands? That's what 'mild' means.