It’s true! Phophorus was isolated in the mid-1600s by an amateur German alchemist from distilling the urine of nuns. Phosphate these days is made by reacting phosphate acid with sulfuric acid to instantly create phosphoric acid and gypsum. It is the seventh most common industrial ingredient in the United States where it’s used in things you expect like soaps, detergents and treating water.
Where you don’t expect it is Coca-Cola, baking powder, and it’s role in refining sugar.
Phosphoric acid is great at rust removal which is why Coca Cola can remove rust. Seriously, it can.