One thing I have not been able to find... are today's X-rays sensitive enough (i.e., high definition) to recognize metal dust particles? See a small chunk of metal is a no-brainer, and I can imagine a high concentration of metal dust in one area as being visible like a clouding of the image (similar to a tumor). But a few specs of metal dust picked up while working? I didn't think the definition was nearly high enough for that...