Donuel... "Even one atom    of PU lodged in your lung will kill tissue and then promote cancerous growth."

My old man (RCAF, Ground Nuclear Defense) told me a long time ago that tobacco causes emphysema and other nasties but it does not cause cancer directly. Rather, it allows cancer to be caused by sunstances which become lodged in the lung and are either radioactive themselves or are metals which can be affected by magnetic fields induced by close proximity to electric current.

And, no, I don't care to discuss it any further with anyone for any reason whatsoever.