Scientists unlock secret of how onions make us cry

CHICAGO, Ill. (WPVI) -- If cutting up onions makes you cry, a new discovery may some day dry those tears.

Scientists have found out exactly how an enzyme in onions produces the compound that makes eyes sting and water.

They've known about the compound, known as LF.

However, lab studies on LF have proven difficult, because it breaks down and evaporates quickly.

So now, a team from Japan has reportedly created 'tear-free' onions by neutralizing the enzyme within the seeds.

No word when those seeds will go on the market, but they are expected to be very pricey.

The development was reported in the journal ACS Chemical Biology, of the American Chemical Society.

To see a video of the mechanics of those tears, click here.