We have all been there. Just hanging out in the kitchen while Mom’s cooking dinner and out of nowhere there are tears running down your face. Are you sad? No. Are you laughing too hard? Probably not. At the peak of your confusion you happen to look to your left and see Mom over there cutting up an onion and suddenly it all makes sense.
But then you think, “Why the heck is this thing making me cry?” Well, you’re about to find out.
Onions are part of the Allium species of plants, which have a tendency to absorb sulfur from the soil. When an onion is cut into, enzymes are released and they react with the sulfur to create amino acid sulfoxides.
The chemical reaction creates syn-propanethial-S-oxide, which is a combination of sulfuric acid, sulfur dioxide, and hydrogen sulfide. When the gasses from this substance come in contact with the fluid in your eye they cause the burning sensation that you feel when hanging out around freshly cut onions.
The burning sensation then causes the eye to naturally produce tears in order to relieve the discomfort that your eye is feeling.
So, next time you’re around some freshly cut onions, be sure to tell everyone what is actually going on.
From the eye doctors, opticians and staff at Rinkov Eyecare Centers. We’ve provided comprehensive eye exams, contact lenses, eyeglasses, sunglasses and medical treatment of eye disease, such as cataract treatment, in Columbus, Ohio for over 35 years. Come see an optometrist at one of our convenient Columbus locations – Downtown, West, East, Westerville, Dublin, Bexley, Worthington, Nationwide Plaza, and now open in Hilliard!