Weak Nuclear Alchemy, that is the power I am asking about today, a power that was already discussed in What Would Powers Based of the Weak Force Look Like, but I am asking a more specific question. Essentially, in this form of weak nuclear alchemy, the user is able to transform an elementally pure object into a different elementally pure object so long as the material it transforms into is one step away on the weak force "decay chain," ie. one neutron transforms into 1 proton per atom in the transition. They are able to somehow generate enough energy to achieve this transition through magic, but magic does not effect in any way the energy or radiation released by this reaction. Besides this, the practitioner also has to touch the object they're transmutating with their bare skin. So, the question is, how much stuff can they transform before they die, blow their hand off, or something like that? We're probably talking about how many atoms they can transform so I am pretty sure the question I am asking is how many moles of material can I transform before the weak nuclear alchemy becomes truly dangerous for me?
Edit:
I need to specify something that is relevant to the answer of the question. Currently, the best answer I have says my alchemists can transform 1 micro-mol of material safely, but this is taking long-term safety in mind. I am not concerned about long-term safety, only short term safety. The thing is, these alchemists will generally have monthly access to healing magic which can deal with minor inconveniences like cancer and stuff, so the main question is how much of a mol could they transform per month without dying?
Think of the healing magic as being far better than, and at the same time far more expensive then, modern technology, so they can heal from pretty much any injury but only at afew set times so they can't survive things like acute radiation poisoning. I would need to no more about the effects beta radiation has on the human body to say more.