[rflrob]

While the Linear, No Threshold model is relatively widely used by regulatory and safety bodies, evidence for it (or any other competing mode of low dose exposure) is quite weak.

https://en.m.wikipedia.org/wiki/Linear_no-threshold_model

[WithinReason]

An interesting addition is that a small amount of radioactivity might even be good for you:

https://en.m.wikipedia.org/wiki/Radiation_hormesis