Also: are the most conducive
- oxygen
- hydrogen
- nitrogen
- carbon
That’s more a question of semantics (and dosage I suppose). Radioactive elements can be therapeutic if used properly in a hospital (X-ray scan, radiation treatment for cancers, etc…).
More to the point, radiation spurs mutation. Mutation 99.9% of the times is bad, but that 0.1% chance of a beneficial mutation is a major driver of evolution. So in a way radioactive elements help create new ‘forms’ of life via speciation.