In some aspects, radiation from excited electrons and that from radioactive sources is similar, in that the damage inflicted is done the same way, through similar means. The difference is the particle involved. In radio, it's always an electron. In other radioactive sources, electrons get joined by other subatomic particles- which gets nasty fast because they're all bigger than electrons.
I apologize that I must do this tty, but this is all malarkey.
Electromagnetic radiation is all of the same form, the force carrier is the photon (not the electron). The difference in energy/frequency of the photon packet is what causes the different effects we see.
On the high energy side of the spectrum (high frequency/short wavelength) we have cosmic rays, then gamma rays, and x-rays. All of these are ionizing radiation. Gamma rays basically blow molecules apart. X-rays excite electrons on the inner shell of molecules (much higher energy than valence electrons) and can also break bonds and ionize species.
Then we get to the UV-Vis part of the spectrum we're all familiar with. The wavelengths here are about 20-400nm (UV) and 400-700nm (Vis), whereas gamma rays are less than 10pm by contrast (smaller than diameter of an atom). UV-Vis radiation excites valence electrons.
Then we get to infrared, which cause an excitation in vibrational levels of molecules--then to microwaves which cause excitation in rotational energy levels (lower energy than vibrational level excitations), then finally to radiowaves which interact only with the nucleus, and are used in nuclear alignment studies (the basis for MRI and NMR technologies). The wavelengths here are meter sized.
Ultimately the difference in effects has to do with the energy of the photon pack, because energy levels in molecules are quantized, radiation must match exactly the required energy input for a given excitation in a molecule or it will not interact appreciably.
A more physical way to look at this is to think of the size difference between the radio wave and an atom. The wavelength is so long that the chance of a photon propagating along that path interacting with a single atom is incredibly unlikely--and even if it were to the energy would be much too low to make any changes to the molecules.
Now the other type of radiation you're talking about is nuclear radiation. This occurs when the actual nuclei of an atom or an atom that is a component of a molecule breaks apart into two new daughter nuclei or change their charge state.
In alpha radiation you actually lose two protons and two neutrons, known as an alpha particle. In beta radiation you either emit a high energy electron, or you emit a high energy positron accompanied by an electron antineutrino.
These are different processes.
Beta radiation is some of the most dangerous radiation (along with gamma ray photons), because it is very penetrating. However, if ingested, alpha radiation is much more damaging than either.
While there is radiation on the electromagnetic spectrum which can be responsible for the same types of problems as those occurring from nuclear decay, they are two very different processes.
