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Storing Drinking-Water in Copper Pots Kills Contaminating Bacteria (2012)

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Re: Storing Drinking-Water in Copper Pots Kills Contaminating Bacteria (2012)

#131

Post by vram22 »

throwaway5752 wrote: post #107
vram22 wrote: post #90

Earlier quoted context omitted.

> Copper, silver, and gold are in the same family of elements (group 11) and lead is in the carbon family. By that, I'm guessing you mean in the periodic table. Been a while since I looked at that, should check it out again out of interest.

Yup, a lot of chemical properties are dictated by the number of outermost free ("valence") electrons, and atoms in columns in the periodic table all have the same number of valence electrons, hence similar chemical properties. The University of Nottingham's School of Chemistry has some great, brief videos on various elements if you're ever interested: https://www.youtube.com/channel/UCtESv1e7ntJaLJYKIO1FoYw

Interesting, will check them, thanks.

Re: Storing Drinking-Water in Copper Pots Kills Contaminating Bacteria (2012)

#132

Post by gumby »

Tomminn wrote: post #109
JumpCrisscross wrote: post #81

Earlier quoted context omitted.

> 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.

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...

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

Re: Storing Drinking-Water in Copper Pots Kills Contaminating Bacteria (2012)

#133

Post by ska »

justincormack wrote: post #126
ska wrote: post #92

Earlier quoted context omitted.

Copper pots are used for cooking because of the superior heat transfer, but you are not cooking with copper directly. They are "tinned", and this coating needs upkeep. You can't really cook with it directly because it's too reactive with acidic foods.

Modern ones are coated with stainless steel which needs no maintenance

true, modern ones are electroplated - can still be called tinning in practice although that's inaccurate. It doesn't need anything like the same maintenace as old style.

The point was more that nobody really cooks directly with copper, and did not historically.

Re: Storing Drinking-Water in Copper Pots Kills Contaminating Bacteria (2012)

#134

Post by samstave »

peterwwillis wrote: post #115
rblatz wrote: post #83

Earlier quoted context omitted.

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.

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…

only water, and once bourbon.

Re: Storing Drinking-Water in Copper Pots Kills Contaminating Bacteria (2012)

#135

Post by tossaway1 »

vmarquet wrote: post #129
throwaway5752 wrote: post #40

Earlier quoted context omitted.

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 ).…

Little known fact: lead might be one of the reasons of the decline of the Roman Empire, because they used it inside the pipes carrying water. https://en.wikipedia.org/wiki/Lead_poisoning#History

I would have thought that was a well known fact. It's brought up virtually every time lead toxicity comes up...

Re: Storing Drinking-Water in Copper Pots Kills Contaminating Bacteria (2012)

#136

Post by DougN7 »

askvictor wrote: post #97
vram22 wrote: post #71

Earlier quoted context omitted.

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.

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

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.

Re: Storing Drinking-Water in Copper Pots Kills Contaminating Bacteria (2012)

#137

Post by Filligree »

nxc18 wrote: post #108
Filligree wrote: post #17

Earlier quoted context omitted.

I somehow got copper in my fish tank... Don't.

Lots of fish medication is copper based due to antibacterial/anti-parasitic action. Real bad for invertebrates though.

In retrospect, the dead snails should have been a sign. I got a lot more copper in the water than fish could survive.

Fortunately there were no fish in it yet.

Re: Storing Drinking-Water in Copper Pots Kills Contaminating Bacteria (2012)

#138

Post by 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 [††] http://pubs.acs.org/doi/abs/10.1021/am507746m

Re: Storing Drinking-Water in Copper Pots Kills Contaminating Bacteria (2012)

#139

Post by mangamadaiyan »

vram22 wrote: post #73
mirimir wrote: post #45

Earlier quoted context omitted.

For rasam, it's tin, not lead. But lead has sometimes traditionally been used in cooking etc, because many lead salts are sweet :( That's why children chew on flakes of leaded paint. They're like candy :(

>For rasam, it's tin, not lead. Could be, I was going by what I've heard from elders. They could have been wrong.

It is indeed tin, despite the name you heard (eeya-chatti, or eeya-pathiram I'm sure) from your elders.

The Tamil word Eeyam has two overloaded meanings, one is tin/pewter, the other is lead.

Unfortunately, "Eeyam" is almost always translated into "Lead".

Re: Storing Drinking-Water in Copper Pots Kills Contaminating Bacteria (2012)

#140

Post by zxv »

ComputerGuru wrote: post #78
Moto7451 wrote: post #61

Earlier quoted context omitted.

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.…

Yes, that's all I've ever heard. However: http://onlinelibrary.wiley.com/doi/10.1002/14651858.CD002106... http://www.burnsjournal.com/article/S0305-4179(16)30056-0/fu...

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.

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