Just wondering if i were to have a ct scan of the chest what is the exposure to radiation and the likelihood of developing cancer from it?

Chest CT radiation: exposure depends on the type of chest CT performed. Total effective dose for a "standard" Chest CT is about 7mSv. The theoretical increased lifetime cancer risk is about 0.04%. This is theoretical, there is some debate whether doses in this range have any effect. However, to put that risk into perspective, the average person is about twice as likely to die from drowning.