Toxicological trivia from December 17, 2015:The onion (Allium cepa L.) (Latin cepa = onion), also known as the bulb onion or common onion, is a vegetable and is the most widely cultivated species of the genus Allium. This genus also contains several other species variously referred to as onions and cultivated for food.Onions are cultivated and used around the world. As a food item, they are usually served cooked, as a vegetable or part of a prepared savoury dish, but can also be eaten raw or used to make pickles or chutneys. They are pungent when chopped and contain certain chemical substances which irritate the eyes. No one should have gone unnoticed that when you peel an onion, in a few seconds you stop to mourn as a cupcake. The molecule that produces irritation and watery eye contact is:a) Allinase;b) Trans – (+) – dimethyl S- (1-propenyl) -L-cysteine;c) Syn-propanethial-S-oxide.

Correct answer: c. Read more with Spanish article "Peeling Onions: Blame the tears is the syn-propanethial-S-oxide". Read also in WP and Why Do Onions Make You Cry?