Hi Bex. I think I can pretty much rule out mercury as the cause for my sensitivity, because I simply didn't have a problem with that *before* my removal. Only after the removal did I start to have problems with EMFs, and this problem has slowly faded away like every other mercury-related problem with time. I'm not exactly sure about the mechanism, but somehow electromagnetic fields must make the immune system more aggressive against pathogens, because according to the above assumption, EMFs can't still kill the pathogens directly. Zappers probably stimulate the immune system, which you get back after amalgam removal, so it won't work at all (or at least inefficiently) if you still have amalgams in mouth. Some claim that EMFs suppress immune system activity, but this isn't consistent with what I have experienced or with those who have got successes with a zapper.