Is there toxic in the skin of an onion?

Onion skins are not toxic; however, they are typically not consumed due to their tough texture and slightly bitter taste. The skin contains antioxidants and beneficial compounds, but most nutrients are concentrated in the flesh of the onion. While eating small amounts of onion skin is generally safe, it is not commonly done. For culinary use, it's best to focus on the edible parts of the onion.