Tear no More

Did you ever wonder why your eyes tear up when you chop or slice onions?  Well, they are grown in the ground and like garlic and they absorb sulphur.  Chopping the onions releases certain enzymes which react with sulphur, creating amino acid sulfoxcides.  These in turn create the highly unstable syn-propanethial-oxide.  Whew!  

When this gaseous substance comes in contact with the moisture in your eyes they start to burn.   When your brain gets the message that there is an irritant, it kicks in the lachrymal gland which tries to flush out the irritant with a flood of tears.  Now, to cure this problem, put them in ice water for a few minutes to slow down the enzyme/sulfoxides reaction rate.  Voila!  No more tears.  Thank Google for this wisdom.