Why do waters runs through eyes while cutting onion?
Onions, like other plants, are prepared of cells. The cells are bisected into two sections parted by a membrane. One side of the membrane comprises of an enzyme which helps chemical processes occur in your body. The other side of the membrane contains molecules that contain sulfur. When you cut an onion, the contents on each side of the membrane mix and cause a chemical reaction. This reaction produces molecules such as ethylsulfate which make your eye water.
How to get over it?
To avoid crying when you cut an onion, cut it under a running tap of cold water. The sulfur compounds disintegrate in water and are rinsed down the sink earlier they reach your eyes. You can also put the onion in the deep freezer for ten minutes before you cut it. Cold temperatures slow down the effect between the enzyme, and the sulfur compositions so fewer of the burning molecules will reach your eyes.