Mango skin has a similar allergen as that in poison ivy, poison oak and poison sumac. My sister cannot touch the skin w/o getting a rash. However, if it's already peeled she can eat it w/o issue. I understand this is not uncommon:
Of this I was aware, and thanks for bringing it up for general knowledge! For me, oddly, I can walk through poison oak no problem, as long as I don't have an open cut. Near a cut, the area will get all "poison-oaky" and rash and itch still.
https://en.wikipedia.org/wiki/Mango#Potential_for_contact_de...