More than 30 years ago as a student at the UW, I was waiting for a cashier or a food service attendant or something like that ... but I was standing waiting near the kitchen. There was a notice to the kitchen workers posted there from UW food services management which stated that workers who washed the stainless pots and pans were not to be overly aggressive at removing the discoloration.

The memo stated that it was much like the polymerized film that developed on cast iron cook wear, and over-zealous scrubbing would merely allow nickel and cadmium(?) from the stainless to leach into the foods.

Don't bitch at me. I didn't write it.