What r the effects of Germanium,Lead &Mercury poisoning?how does some1 get exposure?

Several years ago I was diagnosed with high levels of Lead, mercury & Germanium in my body.. I know that Lead causes ADHD, &mental retardation, & Mercury can cause nerve&brain damage-(& causes widespread pain- at least in my case), but i dont know what effects the Germanium wouldve had, if any effects. I do know the source of Mercury (dental fillings) but i have no clue how I was exposed to Lead or Germanium...I didnt eat paint chips & I hadnt even heard of Germanium, until after the diagnosis... where is it even found?