I'm referring to those health physics (hp) deniers of the radiation hormesis strain.
"This" is called SIRT6 and it plays a major role in DNA repair, especially Non-Homologous End Joining. (NHEJ). The graphic below depicts a double strand break (DSB) in DNA (top) undergoing repair by the NHEJ process. The next images, below the top one, depict how different proteins are recruited to effect the DSB repair. It doesn't include SIRT6 because the graphic is old.
Ionizing radiation produces about 5-7% as many DSB's as Single Strand Breaks (SSB's), and DSB's and SSB's also occur metabolically. Even when a DSB is repaired, typically some nucleotides (DNA's basic units abbreviated A,T, C and G) are gained or lost at the repair sites. Occasionally, there can be large sections of DNA deletions. So, DSB repair is usually actually misrepaired.
With that FACT (DNA repair has fidelity <100%) we conclude there is >0% DNA damage risk associated with ionizing radiation exposure. And as far as we know today, cancer is a result of accumulated DNA damage.
The new study informs us that as cells age (at least in mice), they undergo more NHEJ and lose SIRT6.
Of course, we know what some HP deniers will do........