I don't question the damage it can do and will have supposedly done to Harvey in the movie, like I said, I'm just unsure what great effects it has on the body outside of superficially eating away at material. I do know something about severe burns to the skin from like flames and such causes a buildup of toxic levels of chemicals in the body which is why certain burns kill, not the flesh being burnt but that it causes effects to your blood which kill you; to have your face damaged like Two-Face from fire should be lethal, so it has to be acid.