(in older days, clock industry workers were applying phosphorescent paint on numbers, that was tritium-enhanced, with a paint brush they used to lick to keep the hair straight, and they had terrible cancers... may be the clock bloggers could dig more detailed stories)
Nothing easier: Just sustitute tritium for hydrogen in whatever compound you are making the paint out of.
Suppose THAT persists in the body. Then the tritium persists right along with it for maximal radiological effect. The Fates are kind.
