The article mentions that one risk of taking copper supplements is setting your zinc ratio out of whack. This is a clear example of the government taking positive action on public health.

Yes, but their surface area is 100% copper. You are likely to pass the penny before digesting all the way through to the zincky center.

And 1982 was the year the US penny switched from copper to copper-clad zinc. Some from that year are pure, and others are clad. The pure pennies are heavier. Or you could file a notch in an edge and see if the center reflects whitish or reddish.

This is true, that is why I only eat the "skins" of modern pennies if I don't have any old ones. The inside is where all that nasty zinc comes from.