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Sci-Tech

Swimming pool red-eye isn't from chlorine (It's from urine)

Technically Incorrect: The US Healthy Swimming Program says that when your eyes go red and stingy in the pool it's caused by a chemical reaction between chlorine and urine.

Technically Incorrect offers a slightly twisted take on the tech that's taken over our lives.


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It may look beautiful, but... Stadium Guy/YouTube screenshot by Chris Matyszczyk/CNET

Sometimes you wake up to headlines that make your eyes water.

Usually, they're from the Daily Mail. Sometimes, however, other news sources offer a mere sentence that makes you look back to your childhood and wonder what might have been.

Today, the sentence involves redeye -- the stingy feeling that you sometimes get in your eyes during and after a swim in a pool.

Many people have often assumed this is caused by chlorine. Some even wonder whether they're allergic to chlorine. The truth, allegedly, is that they're being affected by chlurine. This is a name I've just given to the result of chlorine mixing with urine.

And this is apparently what causes eye irritation in swimming pools.

The information was actually released last month by the National Swimming Pool Foundation. Quoting the Center for Disease Control and Prevention, it said: "When nitrogen-containing compounds found in pee, sweat and dirt combine with chlorine, irritants are formed. These substances, not the chlorine itself, irritate the eyes, skin and respiratory system."

There's something tragically malevolent about a simple bodily function causing other parts of the body to malfunction.

It seems, though, that when you get a so-called swimming pool cough, it's caused by the chemical reaction between chlorine and urine actually getting caught in your throat.

One of the potential remedies is to put more chlorine into the pool, in order to kill off more of the bacteria. However, the CDC says that recreational water illnesses (RWI) have increased over the last 10 years. The most common is diarrhea. It says that 20,000 people have been run into the restroom by swimming pool bugs.

I hope your vacations are full of joys.