Every day, your body will probably generate at least one cell that would be cancerous if it wasn’t for your immune system. If that probability goes up slightly as a result of mildly increased radiation that day, it likely won’t overload the immune system’s capacity to deal with it. If it is overexposed to radiation, eventually the greater probability of cancerous mutations exceeds the immune system’s capacity.
Is it cumulative? Or is it probability — which of course goes up if you shower yourself in radiation multiple times a day?
It is cumulative.
https://ionactive.co.uk/resource-hub/glossary/accumulated-dose
Radiation is not a matter of chance, but a matter of how much.
Every day, your body will probably generate at least one cell that would be cancerous if it wasn’t for your immune system. If that probability goes up slightly as a result of mildly increased radiation that day, it likely won’t overload the immune system’s capacity to deal with it. If it is overexposed to radiation, eventually the greater probability of cancerous mutations exceeds the immune system’s capacity.