(Intro)

Hi everyone.  Squeaks and I just finished doing some cooking over in the kitchen.  We wanted to make some delicious onion soup, and while we were chopping the onions for it, we noticed something strange happen.  I started to cry.  Squeaks was worried that I was upset, but I wasn't crying because I was sad.  My eye were just tearing up because of the onions. 

It's totally normal for chopping onions to make people cry, even if they're really happy and having a great day, and that's because crying isn't only for when you're feeling sad.  Your eyes also make tears when they're dry, itchy, or uncomfortable, to help them feel better and stay healthy and strong.  That's what happened while we were cooking.  Something about chopping the onions was bothering my eyes. 

Sometimes, things called irritants, stuff like dust, dirt, or chemicals in the air, can irritate and bother our eyes.  Irritants make eyeballs itchy, dry, and just generally uncomfortable, and we can't use our hands or a towel to get them out because our eyes are really sensitive.  Luckily for us, eyes come with a built-in cleaning system: tears, which work kind of like a special washing machine for your eyes. 

Tears contain a lot of water, which mixes up with any irritants in your eyes that are bothering them.  Then, the tears make their way to the corners of your eyes, up and over your eyelids, and out of your eyes entirely.  That's when they roll down your cheeks, taking the irritants with them.  Crying helps your eyes to feel much better, much faster, even if you aren't sad.

Sometimes, if your eyes still hurt, a little running water can get any leftover irritants out.  I think I'm okay now, and I don't need any running water, but I'm still curious about what part of the onions was causing my eyes to tear up.

Good idea, Squeaks, let's try it.  We've got an onion here, and my eyes aren't watering.  The outside of the onion is dry and not too smelly, and my eyes feel fine so far.  But if we cut it open, something changes.  See, there's a bit of juice that came out and a very powerful onion-y smell, and now my eyes are starting to tear up a bit, too.  I know, it's because of the juice!

Once we cut open the onion, tiny bits of the juice can spread around in the air.  That's why it starts to smell more.  The juice floating around in the air gets into your nose.  That also means it can get into your eyes and since the onion juice is an irritant, your eyes start to tear up to get rid of it.  It's starting to bother my eyes now, but it isn't too bad.  

There are lots of ways to stop the onion juice from getting into your eyes, though.  Some people like to put onions in the refrigerator before cutting them or soak the onions in water first.  That can help by lowering the amount of juice that gets into the air when you finally cut open the onion.

Squeaks, do you have any other ideas?  That's a great idea!  We can wear our lab goggles, and you know, cooking is just like doing a science experiment.  Just like some kinds of scientists, we combine different things, carefully measure out certain amounts, and mix them up in all sorts of ways to create something new, and in this case, it's delicious.  If we're going to be kitchen scientists, dressing the part and wearing our goggles is lots of fun.  

If you want to try this for yourself, ask a grownup for help cutting open an onion and see if one of these ideas keeps your eyes from tearing up, and thanks for joining us.  

If you want to keep learning and having fun with Squeaks and me, hit the subscribe button and we'll see you next time here at the fort.

(Outro)