There are stainless steel soap products for washing hands.

For example, Blomus Stainless Steel Soap:

Simply rub on hands under running water to neutralize odors [...] Negatively-charged stainless steel soap combines with positive charge of cool water to neutralize germs

I used one recently, and it seemed to work to remove meat odor from my hands. I was dumbfounded and didn't want to admit it, but it really seemed to work, and I can't see why. Is this just some sort of placebo effect or some science at play?

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    Just to clarify, is the claim here that stainless steel soap neutralizes odors (a common claim, for which there seems to be at least some supportive evidence), or that it neutralizes germs (a claim I've never heard before, and which seems extremely unlikely)? – tim Sep 4 '16 at 19:56
  • @tim: Both have been claimed, so ideally both. However, if there is evidence that stainless steel soap has a real effect on odors (a big "if), it would be a shame if some nonsense about negative charges were to prevent an answer from explaining that. I'd go ahead an answer the first claim, and acknowledge that you haven't addressed the second one. – Oddthinking Sep 5 '16 at 3:05
  • @tim the way I read it was that it eliminates odors by using the different charges to kill germs. – Aequitas Sep 5 '16 at 3:18
  • Afaik some odors are neutralised by catalytic reaction with the iron, but i can't find the paper I read about it. Does not work for all odors. And the germ things I doubt, even silver would not work that way – PlasmaHH Sep 5 '16 at 20:35
  • Note that a whole bunch of "disinfectant soap" ingredients have just been ruled unacceptable because there is no evidence they disinfect any better than normal soap and water. I would strongly suspect that steel,,-containing soaps do no better and probably worse. – keshlam Sep 6 '16 at 4:19

According to Google an patent for this has been granted to Dirk Zielonka (proprietor of the eponymous "Zielonka Wohnen und Leben GmbH").

According to the patent description the invention doubles as a toilet block, a priest (an implement to clean gutted fish) and is also used in a fishermans knife so you can remove the fish odour from your hands right as you kill the fish.

A German patent application does not mean the thing actually works (personally I still think this is BS), but at least it means the invention has beed inspected by a "Patentassessor" (often an engineer of some description) who decided that it has merits.

It seems nobody else has done an any actual research on this. Wikipedia says that there are no scientific merits to the idea. This seems to be based on linked articles in the NY Times and Wired (that may be have been written by the same stringer from a news agency, since both tell the same anecdote of a chemistry professor who concluded that this doesn't work after washing his hands with it).

As much as it pains me to say, what little evidence there is (i.e. the patent has been granted and the "rebuttals" limit themselves to jokes without research) seems to indicate that there is some merit to the idea that metal bar soap works.

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    A patent does not need to work to be granted. Many pseudo science devices use patents to seem more credible. This is poor evidence that should be removed from the answer. – Oddthinking Sep 6 '16 at 12:24
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    @Oddthinking, in Germany a "patent" is much more narrowly defined than in the US or, apparently, Australia. A German patent is at least examined by somebody who has studied, and successfully worked in, the natural sciences (also there are a lot less things where patent is even applicable). The evidence against the metal bar is not tested at all. I do not believe the thing works, but if I apply the standards of this page I have to weigh the word of a working scientist/engineer against that of a few badly researched articles, and so I tend to fall on the side of science. – Eike Pierstorff Sep 6 '16 at 12:38

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