They're items on a practical level, so nothing stops you from passing them to your companions if they meet the requirements. The only thing in the way is your own RP.

There is also the risk of destroying them by mistake. Didn't try it, I would guess there is at least a confirmation message.

Yes, I think there is a confirmation when you try to destroy an item. Anything in your inventory will behave the same regardless of the slot it goes in, so that confirmation would apply to them too. I'll check it out.