Pool water is sterile because it is treated with chlorine, and chlorine kills bacteria.

The water in that pristine pool may have been treated with chemicals, and it may have very few bacteria in it,(the water is never one hundred percent sterile unless your pool is located in a hyperbaric chamber behind sealed doors), but the minute a human being stick one toe in the water the level of bacteria increases. This is why people working at the public pools need bloodborne pathogens training, because some of the bacteria passed through pools could contaminate your blood.

We have bacteria on our skin. When we get into the pool the bacteria transfers from our skin to the water, leaving the pristine water less pristine.

Myth
I am clean, I just bathed, so I am not contaminating the pool water.

The average human being adds the following to the pool when they get in.

  • 0.14 grams of fecal matter for the average adult, and about ten full grams for a child
  • Between twelve and twenty four ounces of human sweat
  • Eight ounces of urine. This is if you do not actually pee in the pool. This is urine that is on your body when you enter the pool. If you pee in the pool then the urine amount is greatly increased.
  • Millions and billions of microbes that are present on human skin

Myth
Chlorine kills all bacteria.

While you chlorination in your pool is working overtime to get rid of the urine and poop that people have deposited in the pool it is weakened to the point that it can no longer stop harmful bacteria that may be there.

Some of the harmful bacteria that your pool chemicals may be letting live are:

  • E coli
  • Norovirus
  • Legionella
  • cryptosporidium

Myth
Swallowing a small amount of pool water will not make you sick.

When you swallow even a tiny amount of pool water then you introduce all of the different strains of bacteria into your body.

Myth
State laws mandate pool chemical regulations so my public pool is safe.

Wrong. Only sixty eight percent of the health departments in the United States actually check the chlorine, and bacteria levels in public swimming facilities. The Center for Disease Control recommends that the chlorine level in a pool be maintained at between one part and three parts per million, but few public pools actually keep the chlorine level of their pool water that high.

Myth
I should never swim in a pool.

You do not have to avoid pools completely in order to maintain health. There are a few guidelines that you should follow such as:

  • If you swim in public pools make sure they have a shower and regulations that make each swimmer shower before entering the pool
  • If you own your own pool be certain that you shower before swimming and that all of your guests shower before swimming
  • Never allow an animal to swim in the pool with you
  • Shower when you get out of the water. Do not simply rinse off in running water. Use soap and shampoo to cleanse your body
  • Do not swallow pool water.