[kale]

From a toxicity standpoint they are safer. Bismuth can be consumed in medicine (Pepto Bismol). I work in toxicology and we are worried about the "big four": lead, cadmium, mercury, and arsenic. These are from the Q3D guidelines on toxicity. Tungsten and Bismuth aren't on the list at all. Nickel is a unique concern, since it's so dang useful in metal alloys, and a high percentage of people have an allergic reaction to nickel particles.

Edit for a plug: Don't throw away NiCd batteries folks! Recycle them properly!

https://www.call2recycle.org/locator/

[wincy]

I guess I'm getting pretty far off topic from the original discussion, but being allergic to nickel is really annoying.

I bought these nickel free stainless steel pans, because apparently stainless steel has nickel in it to make it shinier. I had to buy three different "nickel free" belt buckles (don't trust random Amazon products to be free of an allergen, even if they claim it!) before I got one that doesn't make my skin break out, and I have to wear plastic glasses because my skin and the metal on glasses doesn't play nice. Even the rivets in some jeans cause problems.

[kale]

Stainless Steel is a huge class of metals, most (but not all) have nickel in them. Also alloys of cupronickel, coin metal, cobalt chromium, and nitinol all have nickel in them. And certain countries lie constantly about nickel content in metal they sell. When we source for medical implants, we have to specify no material from certain countries, because we can't trust their certifications, and we can't re-do all of the certification testing on our own.

Nickel is just too useful (and pre-existing in a lot of metal ores, I think) to stop using it, despite the fact that a large percentage of people are allergic to it.