I believe the difference is that mercury can be absorbed by the skin, copper does not, or at least not by a measurable amount.

I also hate those adds.

'into the blood stream' I've certainly had oxidation tint my skin, but would think if it were a potential threat, like lead for example, electricians and electronics guys would be dead from wiring. Plus 7 years of bathing in pennies hasn't taken any toll on me what so ever. I drop in one of those cement aerators and use it like a parts tumbler. I'm shiny from head to toe.

I hope your not saying what I think your saying, because I think it goes without saying that Pinside is not the place to dispute the chemical absorbency of tissues of dissimilar appendages, because them's fighting words and best left to the cesspools of reddit and lobbies of natural sciences buildings of college campus

It would still seem that toxicity is through ingestion. However its always best to be careful. There's a long history of late discovery of negative effects or means, so if your at risk, its best to take additional measures.

I think the risk from cookware comes largely though imprudent or careless manufacturing. I don't expect anything advertised late night on TV as healthy or in my best interest overall, and both the copperfit and copper pans are marketed to the weary and ill informed.

Now back to my vibratory penny bath, its date night.