What are the sources of radiation exposure while driving a car?

I have heard that driving a car gives a person a higher level of radiation exposure than say, walking.

What are the main sources of this "ionizing radiation" that would be harmful to humans while driving a car?



I have also heard that say "Rock climbing" for 75 minutes can give you 1 msv of radiation.. if this is true, than what about WALKING on the ground which is also made out of rocks in one way or another. What about the cement in my bassment....What are the sources of radiation exposure while driving a car?
he quietness of a manhole cover cannot compare with the wild vapours of nylon I sense in your larynx.What are the sources of radiation exposure while driving a car?
The sources are your car radio/cd player. While the radio is turned on in the car there is a constant stream of information carrying radio waves, in other words, radiation. Many times when I am listening to a cd or the radio I can feel the effects of the radiation.