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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)

#101

Post by bykovich2 »

vram22 wrote: post #96
colechristensen wrote: post #93

Earlier quoted context omitted.

Copper, silver, and gold are also toxic in high doses but not in the same extreme way as lead, which should be kept as close to zero as possible.

Yes, empirically, I guess at least gold cannot be too or immediately toxic, since thin gold leaf is sometimes put on sweets as a decoration in India - usually on peda kind of sweets: https://en.wikipedia.org/wiki/Peda https://en.wikipedia.org/wiki/Vark Silver too, according to the above page.

If I recall correctly, gold is extremely unreactive as far as metals go -- I'd imagine that it may just be more-or-less biochemically neutral.

Edit: I may be dead wrong. https://en.wikipedia.org/wiki/Organogold_chemistry

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

#102

Post by wnevets »

jacobush wrote: post #95
colechristensen wrote: post #93

Earlier quoted context omitted.

Copper, silver, and gold are also toxic in high doses but not in the same extreme way as lead, which should be kept as close to zero as possible.

Gold... toxic?

there was even an episode of house where the cause was gold poisoning.

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

#103

Post by other_herbert »

kpil wrote: post #69
m45t3r wrote: post #26

Earlier quoted context omitted.

Just remember the authors are suggesting copper pots for water storage in developing countries, where people have more chance of dying from diarrhea than from prolonged exposure to copper.

My water is delivered in copper tubes... It can't be that bad, can it?

It probably spends most of it's time in cast iron though and only the last hundred or so feet in copper... I'm in the same boat though

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

#104

Post by notadoc »

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…

Silver has some antimicrobial properties, as well as several other metals.

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

#106

Post by Spooky23 »

jessaustin wrote: post #70
jessaustin wrote: post #34

Earlier quoted context omitted.

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 .

'icantdrive55 the thread is about water supply lines, not boilers or HVAC evaporator coils. I've dealt with a number of plumbers over the last several years, and not one wanted to use anything but PEX for supply lines. Actually a different preference would be a strike against any plumber I'd consider hiring for new work. Also you appear to be hellbanned.

That's a pretty wacky position.

The only meaningful strike against copper is commodity cost.

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

#107

Post by throwaway5752 »

vram22 wrote: post #90
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 ).…

> 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

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

#108

Post by nxc18 »

Filligree wrote: post #17
userbinator wrote: post #8

Earlier quoted context omitted.

Not surprising, there is no contradiction. Copper is toxic to many forms of life.

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.

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

#109

Post by Tomminn »

JumpCrisscross wrote: post #81
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.

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...

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

#110

Post by 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

[1] http://www.npr.org/2011/03/02/134196209/study-most-plastics-...

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