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ashwinpp

> and were proven long ago.

Can you back up your claim?

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First discovered in 1893. https://en.m.wikipedia.org/wiki/Oligodynamic_effect

There are a whole class of heavy metals that act as germicides.

Silver is used (in a cream) to prevent infection in wounds, particularly burns.

I've been making a deodorant created from connecting a few 9v batteries to two copper electrodes in distilled water, followed by the same with two silver electrodes, then blending the results with a bit of alcohol and essential oils. I put it in a spray-bottle and hit the pits with it. Seems significantly more effective than the essential oils alone or conventional products.

For discovery.. (though not 'scientific').. Try 1500-2000 BC

https://www.copper.org/publications/newsletters/innovations/...

Wikipedia would be a good starting point: https://en.wikipedia.org/wiki/Antimicrobial_properties_of_co...

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

[0] https://en.wikipedia.org/wiki/Antimicrobial_properties_of_co...

and while at the time probably based more on observation than a proven mechanism https://en.wikipedia.org/wiki/Copper_sheathing dates to 1700's

And the wiki article has another reference [0] stating, "The first recorded medical use of copper is found in the Smith Papyrus, one of the oldest books known. The Papyrus is an Egyptian medical text, written between 2600 and 2200 B.C., which records the use of copper to sterilize chest wounds and to sterilize drinking water."

[0] https://www.copper.org/publications/newsletters/innovations/...

From [0]

Interestingly, silver may be ineffective against MRSA, while copper is fatal.

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?

> 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...

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

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