Oxalic acid
Today I learned that Oxalic acid causes spinach teeth and is used in 1. Oxalic acid sticks to the calcium in your saliva and form little crystals that don't dissolve. When attached to your teeth, they produces the uncomfortable "spinach teeth" feeling.
After having a large serving of spinach for dinner last night, we were talking about the feeling on our teeth while walking Iris and I told myself that I would figure it out this morning and add it to my Today I Learned.
Members of the spinach and brassica families are high in oxalates. Sorrell, parsley, chives, chard, beet, rhubarb, carrot, collards, and quinoa also contain high levels of oxalic acid. The Virginia creeper produces oxalic acid in it's berries as protection against plant predators in the form of Raphides which are needle shaped crystals facilitating the passage of toxins.
Excessive ingestion of oxalic acid or prolonged skin contact can be dangerous. Oxalic acid is used in cleaning, removing rust, bleaching wood, and whitening teeth. 76% of kidney stones are composed of calcium oxalate and it's used in electrochemical–mechanical planarization of copper layers in the semiconductor devices fabrication process.
- Oxalic acid - https://en.wikipedia.org/wiki/Oxalic_acid