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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)

#81

Post by JumpCrisscross »

gumby wrote: post #67

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 leve…

> 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.

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

#82

Post by mirimir »

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.

I hope that they were wrong. Tin looks a lot like lead. It's harder, but melts at a lower temperature. I doubt that one could coat cookware with pure lead, because it oxidizes too quickly, but alloys (e.g. solder) might be used.

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

#83

Post by rblatz »

samstave wrote: post #47

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

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.

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

#84

Post by deeth_starr »

vram22 wrote: post #71
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 ).…

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.

Worldwide probably...

http://www.motherjones.com/kevin-drum/2015/01/yep-gasoline-l...

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

#85

Post by std_throwaway »

Houshalter wrote: post #36
whatupmiked wrote: post #19

Earlier quoted context omitted.

"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."

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

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

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

#86

Post by std_throwaway »

whatupmiked wrote: post #19
batter wrote: post #2

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

"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."

Safety standards aren't as black-and-white as the law. Some people will suffer way earlier than other people. Some people can tolerate some substances in way higher concentrations than the average person.

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

#87

Post by std_throwaway »

thatcat wrote: post #12
maxxxxx wrote: post #4

Earlier quoted context omitted.

One study is abut storing water in copper pots and the other is about copper in drinking water. Does storing water in pots automatically mean that the copper goes into the water and if yes, how high is the concentration?

>Does storing water in pots mean that Cu goes into water It's not automatic, but depends on pH. Acidic conditions will be favorable to metals leaching into water. The paper cites an initial pH of 7.84, and final pH of 7.94 - so the pH increased slightly as a result of the copper entering the solution. This pH change correlated with 177 ppb Cu concentration in these pots after 16 hours. If initial pH was lower this co…

A quick google says: Drinking water in the US of A must have at least a pH of 6.5. They should have tested with that.

I assume, the copper concentration would increase over 10-fold in that case versus the tested case.

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

#88

Post by sbov »

jessaustin wrote: post #34
LgWoodenBadger wrote: post #27

Earlier quoted context omitted.

How is storing it in copper pots significantly different than "storing" it in the copper pipes prevalent in a majority of houses in the USA?

That's true for houses of a particular age and value. New stuff is all PEX, and has been for some time. Old enough houses would have been cast iron. Cheaper houses (mobile homes, for example) were all PVC for a long time. I had to dig up and repair a sewer pipe yesterday, and was somewhat surprised to find that it was made of clay tile .

Our main sewer line is Orangeburg. I look forward to replacing it soon.

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

#89

Post by semi-extrinsic »

vram22 wrote: post #75
pmoriarty wrote: post #57

Earlier quoted context omitted.

I store filtered drinking water in various plastic containers (often used juice bottles or the bottles that I boght store-bought water in). I wonder how health effects from the chemicals leeching in to my water from these plastic containers compare with the health effects from using copper containers, or perhaps ceramic/porcelain containers as those are supposed to be non-reactive.

I do that too, sometimes, particularly when on trips in rural / forest areas / resorts (refill the plastic bottle at the camp place or resort's restaurant with filtered water from a water purifier) but as a heuristic, to mitigate any possible effects of the plastic chemicals, I throw away the bottle after a week or two.

Doesn't that do the opposite of what you intend? I imagine plastic stuff obviously leaching at a decaying rate.

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

#90

Post by vram22 »

throwaway5752 wrote: post #40
vram22 wrote: post #37

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 sur…

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 ).…

> 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.

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