No need to be a crying mess while cutting onions—there are lots of tips to help prevent the waterworks, including chilling the onion or soaking it in water before chopping, or holding a piece of bread in your mouth while you chop. If you missed these preventive measures and need to dry your tears, here’s how.
Cutting into an onion ruptures its tissue, which contains essential enzymes. When these enzymes are exposed to air, they turn into a gas called syn-propanethial-S-
oxide, with properties similar to tear gas. The fumes waft up toward the small glands in your eyes and cause your eyes to water in an attempt to flush away the chemical gas.
To alleviate the tearing sensation, wash hands thoroughly to avoid worsening the situation. Then, flush your eyes with cool water, or blot the eye area with a damp, clean kitchen rag or paper towel. Relief should come relatively quickly—the gas release peaks at about 30 seconds and subsides after about five minutes.
An exhaust fan or a ceiling fan can help fumes clear out more quickly and soothe your eyes sooner. You can also expose yourself to fresh outdoor air—stand on a porch or in front of an open window and you’ll be back to normal in no time.