This is the first treatment for radiation damage. But not too long ago, someone developed an radiation protection prophylaxis. It was a nano-container, small enough to penetrate the cell wall. Inside it was BHA and BHT, the common preservatives.
This means that a person would somehow absorb enough of these nano-containers for at least one of them to penetrate every living cell in their body. Then when the ionizing radiation caused the creation of free radicals in their cells, the BHA and BHT would neutralize it.
It’s up there with a link, see point 3.