Hmmm, i suppose medical professionals would have a bit of a problem with x-rays and such. I guess they could do a quick test to see what your lead content was for the day and then pump up the power of the x-ray proportionally.
Of course either they'd have to figure out a way to incorporate the lead into the cells without changing the color, or we'd all have to get used to being grey. Although maybe that would kill a third bird as well and eliminate some racial issues :)