[ Oh Noes! The deadly graphene! runaway! ]
It is just carbon the body is made from carbon.
Just like how Carbon and Nitrogen, nitrogen being inert inthe atmosphere, are found abundantly in natural so any compound made from carbon and nitrogen will be inert.
Cant remember how many times I impaled myself on a Ticonderoga #2 and had the tip break off inside my palm or arm. I’m doing good so far.