Hadn't thought of the combination, but know it cause nickel poisoning. I have a book that states kids with braces often go down a full grade in their grade point averages while wearing them. I also wore them and just a few years ago, but told them I needed the least toxic so my braces were made of titanium. The little hooks were stainless or something....not perfect, but better than nickel. Obviously any thing you compound will make things worse with metals. I didn't know this, but Russ has said if you have alluminum poisoning it will make your mercury much worse on you.