Sunday, July 12, 2015

Why is salty tears?

In fact, all the fluids of the body a little bit salty. We just do not usually want to check it. And so, blood and sweat, and urine have in their composition this component. Normal salt - ie, sodium chloride - one of the main components of our body.

But here's an interesting question: Why salty tears do not burn our eyes? After a drop of brine or sea water that gets into the eye, it can cause severe irritation. The thing is that the sodium chloride concentration in the tear is less than 1%, while in sea water it exceeds 3%. Say more: the salt dissolved in the water even create a certain comfort to the eyes, protecting them both from excess moisture (after all, got into eyes unsalted water also causes discomfort) and from drying out.