All deep UV wavelengths are energetic enough to break chemical bonds and the cross sections have quite non-trivial wavelength dependences. The authors of the ar

All deep UV wavelengths are energetic enough to break chemical bonds and the cross sections have quite non-trivial wavelength dependences. The authors of the article claim that 222 nm has a much shorter absorption length in tissue than 254 nm. This would drastically reduce the intensity that can reach the living cells under the outer layers of the skin.