Fact or Myth: Does Chlorine Cause Your Eyes to Burn in the Pool?

poolThis is a HALF-FACT.

Get ready for your daily dose of ick. Just in time for summer, the Centers for Disease Control and Prevention (CDC) revealed the real reason your eyes burn in the pool. Sure, chlorine contributes to red, stinging eyes, but it’s really what the chlorine is mixed with that’s the culprit—urine, sweat, and other waste…like feces!

Here’s what Thomas Lachocki, PhD, CEO of the National Swimming Pool Foundation, has to say:

“People believe that the water is sterile because it’s a pool with chlorine in it, but the reality is as soon as you stick a human body in water, it’s no longer sterile. There are bacteria and germs that can get in the water.”

How much waste does the average person bring into the pool?

  • 0.14 grams of feces
  • 1-2 soda cans full of sweat
  • 1 cup of urine
  • billions of skin microbes

What about children? They can bring upwards of 10 grams of poop!

Chlorine does its best to battle these wastes, but it’s working so hard to nullify the urine and feces and sweat, that it loses some of its ability to wipe out other germs in the pool. Michele Hlavsa, RN, MPH, chief of the CDC’s Healthy Swimming Program, explains, “The chlorine is busy mixing with what we bring into the water, and there is less chlorine to kill the germs. We are kind of using up the chlorine with what’s washing off of our bodies.”

Due to poor circulation and air quality, indoor pools tend to have the most irritants. The CDC suggests keeping windows and doors open, and always showering and using the restroom before and after swimming.

What Else Is Swimming in My Pool? 

Pool water is rife with bacteria that can cause disease, such as norovirus, E. coli, and legionella. Chlorine eradicates these bacteria from pool water, but if you swallow contaminated water before it has the chance to be “cleaned” by chlorine, chances are you’ll get sick.

Cryptosporidium, a parasite found in diarrhea, is perhaps the most common contaminant in pool water. It can thrive in chlorinated water for up to 10 days. A CDC study showed that of the 69 swimmers sick with a waterborne illness, over half of them were infected with crypto.

Here’s another alarming statistic: according to the CDC, only 68% of local health departments regulate and inspect public swimming pools. Swim at your own risk!