
Storing Drinking-Water in Copper Pots Kills Contaminating Bacteria (2012) - Red_Tarsius
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3312355/
======
vram22
Using copper vessels to store water for drinking is somewhat common in parts
of India. Seen it in Maharashtra.

Lead vessels were traditionally used (and may still be) to make certain dishes
(like rasam, a watery lentil-based sour soup) in South India. No idea about
any benefits or the reverse.

Update: Also, I've seen relatives of the previous generation to mine (in
India), sometimes eating from silver plates. Not sure, but I think that may
have been for some supposed health reason too (seeing sibling comment about
silver reminded me of it).

~~~
throwaway5752
Just as a PSA, lead in any quantity is toxic and particularly so for children.
Copper, silver, and gold are in the same family of elements (group 11) and
lead is in the carbon family. Very different characteristics.

edit: I should also note (since bringing up families of elements) that -
supporting your anecdote - silver has known and studied antimicrobial
properties
([https://www.ncbi.nlm.nih.gov/pubmed/16766878](https://www.ncbi.nlm.nih.gov/pubmed/16766878)).
Sadly it has been coopted by quacks, so there's also a lot of misinformation
out there about it, too.

~~~
vram22
Thanks for the info. Yes, I've read about leaded petrol and its effects on the
brain, more so in children. I even read somewhere a while ago (maybe on HN)
that crime had come down somewhat over some decades (in the US?), which was
partly attributed (in the article I read) to reduced use of leaded petrol
(gasoline).

Interesting about the silver study, and agree about quacks.

~~~
askvictor
Interestingly, the guy (Thomas Midgley) who thought to add lead to petrol is
the same guy who thought of using CFCs for refrigerants.

~~~
DougN7
Wow, what a tragic guy:

"J. R. McNeill, an environmental historian, opined that Midgley "had more
impact on the atmosphere than any other single organism in Earth's history."

[https://en.m.wikipedia.org/wiki/Thomas_Midgley_Jr](https://en.m.wikipedia.org/wiki/Thomas_Midgley_Jr).

------
batter
I will just leave it here in case someone will want to employ copper pots:
[https://www.ncbi.nlm.nih.gov/pubmed/10383875](https://www.ncbi.nlm.nih.gov/pubmed/10383875)

~~~
whatupmiked
"Copper content (177±16 ppb) in water stored in copper pots was well within
the permissible limits of the World Health Organization. Copper holds promise
as a point-of-use solution for microbial purification of drinking-water,
especially in developing countries."

~~~
Houshalter
Yeah but they didn't test waters of different ph levels. I'm not sure if that
would be an issue though.

~~~
std_throwaway
It could be an exponential curve and also be influenced by other ions in the
water.

------
ComputerGuru
Silver is also known to have antibacterial/antimicrobial properties and is
used both as a coating on handles, surfaces to prevent bacterial buildup and
also in typical creams as an antibacterial option (however, I do believe a
recent study showed it to be no better than a control when applied topically
to burns, which is/was one of its primary uses).

Both copper and silver oxidize unpleasantly very quickly, though.

~~~
zxv
Silver sulfadiazine 1% cream is a highly effective antibiotic for preventing
infections in deep burns.

In my experience, while while the wound is open, this was the only cream that
had no skin reactions, and that made it far easier keep it on 24/7\. The cream
kept air out, greatly reduced pain. Eliminating infection allowed more rapid
healing.

I don't know whether it's prescribed today, but it was the only cream that was
effective at both reducing pain, and speeding healing.

~~~
Moto7451
Yup, it is still prescribed. They gave it to me after I had surgery on ingrown
toenails on both sides of both big toes [1]. My Podiatrist used acid to burn
away part of the nail matrix to prevent the outer quarter of each toenail from
growing, reducing my toenail to half width. That prevented the problem from
happening again [2]. Silvadine kept my toes from getting infected further and
they healed rather painlessly. All in all good medicine.

[1] Genetics and apparently bad grooming habits for the win! [2] A smashing
success for ten years and counting. About 1/8 of each side grew back but it's
not physically possible for me to get ingrown toenails unless I intentionally
try to induce them.

~~~
ComputerGuru
Yes, that's all I've ever heard. However:
[http://onlinelibrary.wiley.com/doi/10.1002/14651858.CD002106...](http://onlinelibrary.wiley.com/doi/10.1002/14651858.CD002106.pub4/abstract;jsessionid=2C8558BCF7F744704A845EE42ACF309B.f03t03)

[http://www.burnsjournal.com/article/S0305-4179(16)30056-0/fu...](http://www.burnsjournal.com/article/S0305-4179\(16\)30056-0/fulltext)

~~~
zxv
Wow, thanks for the references. My experience was 10 and 15 years ago, and the
newer dressings sound great.

Conclusions the first link: "silver sulphadiazine (SSD) was consistently
associated with poorer healing outcomes than biosynthetic (skin substitute)
dressings, silver-containing dressings and silicon-coated dressings".

Results in the second link: "Many dressings showed superior healing properties
compared to SSD, but no dressing was able to show a clear benefit over SSD
regarding infection. The number of dressing changes, pain and patient's
satisfaction are more favourable in the newer dressings, especially with solid
and biological dressings."

These were certainly the critical factors for me -- reducing pain made it
easier to keep applied. Reducing number of changes is icing on the cake.

For deep burns, debriding the wound is an extremely painful process. If the
biosynthetic or silica materials reduce that, it'd be a huge advantage.

------
emptybits
"We had also reported the benefit of using a copper-based device, contrived by
us, which was as effective as the pot but at a fraction of the cost." [12]

[12]
[https://www.ncbi.nlm.nih.gov/pubmed/19230946/](https://www.ncbi.nlm.nih.gov/pubmed/19230946/)

(Device spoiler: Water in glass bottles with copper coils.)

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samstave
I have a copper water bottle that I bought online from India:

[https://i.imgur.com/3k2QBQI.jpg](https://i.imgur.com/3k2QBQI.jpg)

I love the thing, and I was drinking water out of it...

But one time I put alcohol in it... and I took a few sips from it and I almost
immediately started feeling nauseous and weird... now I'm scared to use it,
even for water.

~~~
rblatz
A Moscow Mule is typically served in a copper mug, and I'd think the negative
effects from the alcohol would be the primary thing to worry about.

~~~
peterwwillis
The thing to worry about would be poisoning from copper toxicity (by misuse
above, or by overuse of copper sulfate), or if made with beryllium, beryllium
poisoning. If somehow 30mg/kg of copper were swallowed, it is potentially
lethal. And if any food residue is left stuck to a piece of copper cookware,
it should be thrown out immediately so it doesn't leech copper out.

If all he ever did was serve a cold moscow mule using his "copper water
bottle", maybe the alcohol is the problem. But we only know he used it to
drink water and alcohol. We don't know if it's lined, or if the lining was
damaged, or if he used a hot or acidic liquid inside it at some point, or
whether it has a corrosive residue.

~~~
samstave
only water, and once bourbon.

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Overtonwindow
The antibacterial properties of copper are well known, and were proven long
ago. I think this is just someone looking for something to research and write
a paper on.

~~~
ashwinpp
> and were proven long ago.

Can you back up your claim?

~~~
sndean
Not sure about copper pots specifically, but Wikipedia has a reference
suggesting 1893 [0].

[0]
[https://en.wikipedia.org/wiki/Antimicrobial_properties_of_co...](https://en.wikipedia.org/wiki/Antimicrobial_properties_of_copper#Mechanisms_of_antibacterial_action_of_copper)

~~~
ashwinpp
Thanks. Should have googled.

However, upon closer inspection, it seems like there was a wave of research
during 1960s which looked at Copper ion concentration between 0.02 - 10g/L

In the 2000s there was another wave of research looking at antimicrobial
properties, however sampling a few of them, it does seem like they were seen
as growing surfaces rather than containers for water purification.

So, I guess it was observed for a long time, scientifically studied fairly
recently, and not in particular whether it was viable in a practical setting?

~~~
sndean
> it does seem like they were seen as growing surfaces rather than containers
> for water purification.

> So, I guess it was observed for a long time, scientifically studied fairly
> recently, and not in particular whether it was viable in a practical
> setting?

It's pretty likely that no one really looked into the antimicrobial properties
of copper surfaces until the advent of biofilm research (essentially Bill
Costerton's paper(s) [0][1]). Without that idea, there wasn't a way to talk
about or study what was happening, and there was no funding.

So, yeah, the better studies would've come out around ~2000.

I don't see a very practical use for suspensions of copper compounds as
antimicrobials (maybe topical treatments only), but lots of uses for copper
surfaces.

[0]
[http://www.nature.com/nrmicro/journal/v12/n11/full/nrmicro33...](http://www.nature.com/nrmicro/journal/v12/n11/full/nrmicro3343.html)

[1]
[http://jb.asm.org/content/194/24/6706.full](http://jb.asm.org/content/194/24/6706.full)

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gumby
Copper pots have interesting properties. For a long time I had read (and
scoffed) that eggs should be whipped in a copper pot for best results. But it
turns out that when you do that, striking the side of the pot liberates
electrons that bond with the albumin and make the protein stiffer.

As for the comment about silver: it does have some antimicrobial properties.
I'm amazed the effect is noticeable at the macro level of eating utensils.

~~~
JumpCrisscross
> _striking the side of the pot liberates electrons that bond with the albumin
> and make the protein stiffer_

Have a source? I'm curious if one can "cook" an egg by submersing it in cold
water through which a current is run.

~~~
Tomminn
I think it's the whole copper atoms[1] that get liberated and bind the
proteins.

[1]
[https://www.nature.com/nature/journal/v308/n5960/abs/308667a...](https://www.nature.com/nature/journal/v308/n5960/abs/308667a0.html)

~~~
gumby
Thanks for digging this up. I should have guessed it was McGee who figured
this out. He's an amazing scientist (and cook).

------
newyankee
Many families in rural India use copper pots for this reason

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epmaybe
Makes me wonder, is there a way to make sure that no copper is still present
after the microbes are all dead? Like throw some penicillamine in there to
chelate the exact quantity of copper dissolved?

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CalChris
Copper has been used as a _biocide_ in antifouling paints on boat bottoms for
decades. The _USS Constitution_ was copper bottomed in 1797.

[https://ussconstitutionmuseum.org/2015/08/12/copperbottomed/](https://ussconstitutionmuseum.org/2015/08/12/copperbottomed/)

------
redm
Because of copper's antibacterial properties, I investigated putting copper
sink faucets in my house remodel. While it's true that it works well
initially, over item film builds up on the surface preventing the benefits.
You have to clean them constantly to get the benefit.

~~~
kwillets
Uh, copper tube is a common supply piping.

~~~
redm
You aren't touching the inside of your copper pipes, you are touching your
faucets.

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nashashmi
Anyone wanna theorize why? Seeing some of the comments here about silver and
gold tells me it might have something to with the high conductivity of these
metals.

As electrons flow through them, the germs are dying.

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theprop
Probably a good idea thus to use all copper pipes in your home!! Using copper
vessels would've been great in an era where there weren't industrial
pollutants like lead or PFOAs or other things...nowadays in India just a
copper vessel wouldn't be sufficient.

In the US as well there are various contaminants in water supplies all over
the country from PFOAs to lead so it's a good idea to use a water filter or
such. I don't think there's much danger of bacteria in US drinking water.

~~~
Tyr42
There was a problem with scurvy when people stored the lime as juice in copper
containers and completely removed the vitamin C in the process.

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ethn
A few years ago GeorgiaTech† created a special anti-bacterial copper alloy
(Cu-PANI††), which is now significantly used in the Atlanta Airport drinking
water pipings.

[†] [https://www.truepani.com](https://www.truepani.com) [††]
[http://pubs.acs.org/doi/abs/10.1021/am507746m](http://pubs.acs.org/doi/abs/10.1021/am507746m)

------
tokenadult
What follow-up has there been on this since the 2012 publication in a rather
obscure journal? Most importantly, is there a source of copper vessels in most
countries that is as inexpensive as other means of reducing bacterial load in
drinking water?

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jschwartzi
So could we also make door handles out of copper, or does it only work for
water storage?

~~~
blacksmith_tb
Yes, some hospitals use copper plated surfaces with good results:
[http://mobile.reuters.com/article/idUSTRE76031820110701](http://mobile.reuters.com/article/idUSTRE76031820110701)

------
freeflight
Sounds like a way more expensive version of SoDis [0] Why use expensive copper
when you could instead recycle, otherwise useless, PET bottles to do a similar
job?

The only potential drawback I can think off is that some PET bottles seem to
leak "hormone-like chemicals" [1]. Tho, reading trough the comments copper
pots also seem to have some toxic effect on the water.

[0]
[https://en.wikipedia.org/wiki/Solar_water_disinfection](https://en.wikipedia.org/wiki/Solar_water_disinfection)

[1] [http://www.npr.org/2011/03/02/134196209/study-most-
plastics-...](http://www.npr.org/2011/03/02/134196209/study-most-plastics-
leach-hormone-like-chemicals)

