I read somewhere that the average human has 0.1 milligrams of uranium in their body. How did it get there, and does it do anything?

Question

I read somewhere that the average human has 0.1 milligrams of uranium in their body. How did it get there, and does it do anything?

In: Biology

Answer 1

This is a very small amount, and the radioactivity of U-238 is very mild. One can calculate how much radiation this would generate: it is about one single decay (an alpha-ray particle emitted) per second – which is negligible. So that uranium is essentially doing nothing of consequence.

For comparison: the largest contributor to typical humans’ radiation exposure comes from Radon in the air. That yields about 100 decays per second per cubic meter (i.e. 35 ft3 for Americans)!