Nickel- or chrome-plated instrument keys and buttons could well become a problem.

I'll keep that in mind if I ever get to the point of affording a concertina where that's a possibility. My Stagi has some variety of ivory colored plastic for the buttons. I'm hoping the thick fabric won't be porous enough to continue the problem, though I can slip a plastic sheet in between the leather and the fabric "slipcover" I've made for the straps just to be sure.

The idea of this worsening is scary, though, and dealing with the shoe issue bound to get tricky very soon too. I'm searching for makers of shoes with natural/non-chrome tanned leather through folks who do historic re-enactment. I'm hoping I could get leather straps from them, as well. ( IanC, wish I could take you up on the possibilty, but I'm in the Cleveland in Ohio, US, rather than UK.) I don't look forward to finding other things that are going to aggravate this sensitivity. I also don't look forward to having to go the doctor over this, but I suppose I'd better.

Thanks for information& etc.

Joanne in Cleveland