Medical advices are by nature always in the "extreme" side of things
Components can differ between each inks
I would always stick to a given medical advice regardless of how extreme it may sound
There are indeed some cases where it goes to shit, altough those reports are always to be taken with a grain of salt unless you have been trained to read a scientific paper AND have some basic dermatology knowledge
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5142484/#!po=5.55556
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4799043/
Take care