[tirwin]

We were discussing this here recently in another thread.

Apparently cadmium plating has some environmental concerns but is still used in aerospace where zinc isn't a suitable substitute.

But it's actually the yellow chromate that is used with both yellow zinc and yellow cadmium that is toxic. (Yellow chromate is what gives it the color.) So yellow zinc has some of the same environmental/health concerns. Yellow chromate is nasty stuff. You can buy it from hobby plating supply stores even though it is a known carcinogen.