Problem is radiation is a much a "trigger" word
As a professional pilot you should be aware of the risks of radiation.
True, and with that mind we should be aware that mammothskier makes a valid point...
Ground-level radiation isn't what should bother you.
It certainly should "bother" you, or at least be of interest to you if you live in certain parts of the world...(..e.g. Anyone else here ever lived in an area with granite bedrock, perhaps in a house constructed on granite.?)