When you get out of the pool, why is your vision filmy and cloudy? Does this damage your eyes?

- asks Margaret from Ohio

July 16, 2007
"Oh no! Will the pool water sting my eyes?!" [CREDIT:]
"Oh no! Will the pool water sting my eyes?!" [CREDIT:]

Ahh, the lazy days of summer. The sun is shining, the weather is warm and there’s nothing better than taking a dip in a swimming pool to cool down and relax. But, sometimes this quintessential summertime activity can leave your eyes itchy and irritated.

Your eyes are experiencing what the American Optometric Association calls chemical conjunctivitis—a swimming pool induced case of pink eye, only this version is just an irritation and resolves on its own without treatment. Chlorine can be blamed for causing the discomfort.

Chlorine, a basic ingredient for many household cleaning products, is contained in swimming pool chemicals, such as calcium or sodium hypochlorite, which act as ‘antimicrobial pesticides’, killing bacteria and controlling algae in the water.

Since pool water is open to contamination from the air and all the swimmers in it, chlorine, along with other chemicals such as iodine and algaecide, are added in high concentrations to fight off disease spreading organisms.

The average, backyard in-ground pool holds about 33,000 gallons of water, according to the Infinity Swimming Pool company. To ensure the water is clean, about 12- to 95-percent chlorine must be used because factors such as evaporation and sun exposure can cause the chemicals to degrade. According to the EPA, the average household cleaner contains about two percent chlorine, while standard bleach contains only about five percent.

The chlorine’s pH level is one cause of eye irritation. PH—a measurement of how acidic or basic a substance is—can be measured on a scale of one to 14. Since the pH of normal water is seven, this is considered a neutral pH; anything less than seven is acidic and anything higher than 7 is basic. The pool’s pH must be at an appropriate level in order for the chlorine to be effective. A pH level between 7.2-7.8 is considered acceptable.

Chlorine is 100-percent effective against bacteria at a pH of 6.5, but this is far too low for our skin to handle—it would be like taking a refreshing dip in acid. At the level used in pools, chlorine is less able to break down bacteria, fats, oils and everything else we take into the water with us. According to the Australian Broadcasting Corporation’s Science Forum, if these compounds are not completely broken down, they can also cause stinging eyes and irritation.

Likewise, an over-chlorinated pool can put you at risk for eye irritations: If there is too much of the compound, our eyes can itch and sting from over-exposure. Normal chlorinated pool water should not do any permanent damage to eyes, but some may be more sensitive than others.

Although not usually a problem, there are all kinds of bugs living in swimming pools…and also in freshwater swimming sites, like lakes and rivers. One of these creatures, called acanthamoeba, can cause sever pain and damage to your eyes, and may even result in the need for a corneal transplant, says Dr. Burt Dubow from the website All About Vision.

Blurry vision as a result of freshwater swimming is usually attributed to the cleanliness of the water. Certain types of bacteria and algae can be especially harsh on your eyes. One of the most common is called cyanobacteria, also known as pond scum. Cyanobacteria is often a result of warm, stagnant waters—so the best way to avoid this is to swim in lakes that are sparkling clear and pristine.

Prevent irritation when swimming in fresh or chlorinated water by wearing goggles when swimming—especially if you wear soft contact lenses. Dubow says that water can change the way your contact lenses fit, making them too tight and causing eye problems.

Flushing your eyes with cool, fresh water after your swim is an easy way to calm any eye irritation. Saline eye drops are also a simple fix for sore eyes, making them an essential beach item for this summer season.

About the Author



I think it is normal. It happens to me always. However, if you are swimming in a chemical swimming pool, it will affect your eyes badly

The chlorine generator in fact utilizes the salt to make a chlorine gas that dissolves into the

Cypriot pool says:

Am currently on holiday in Cyprus, yesterday I experienced the smokey vision after being in the pool. It eventually went away after rinsing and resting my eyes. Today I went in the pool again, and it happened again. However instead of fog, every bright light has a visible halo around them

Eyes remain blurry/hazy with bright lights hazy even after a whole day after swimming in a city pool. Any solutions to fix this?

Matthew Seal says:

I’m certain about what happened after I swam! I had my eyes open after the pool and stuff and when I got out after a couple hours, my eyes are cloudy and I hardly see. This pool is a public underground and I think the chlorine wasn’t really strong because it didn’t hurt my eyes. Now, will I need glasses for this problem?

Hot Tub says:

Great advice.

Keeping a pool or hot tub sparkling and healthy is a fine balance. Remember the Rio Olympics diving pool when it went green. Yikes!!!

A good pair of googles are an asset as you point out. If they do let in water, make sure to wash them out with fresh water if possible.

Thanks for your post, I knew a lot but you taught me a lot more things I didn’t know.

Larry the Lifeguard says:

No, I can tell you with certainty that chlorine alone in a properly maintained swimming pool cannot cause blindness. I have been swimming hundreds of yards at a time for many years, and I literally never wear goggles. There will be some redness, and discomfort, or even temporary blurriness, but this is a normal reaction

The acidity of the pool is another matter, however. There are other aspects that could possibly lead to more serious damage to the eyes. For an indoor or outdoor swimming pool to get to such a condition in which permanent chemical damage could occur, would indicate a gross lack of responsibility on the part of whoever is responsible for maintaining the chemical levels. However this is highly unlikely at public pools run by corporations.

Lyric says:

How long is the blurriness exactly suppose to be? It’s been almost 2 hours since I got out of the pool. I put lubricant eye drops in my eyes and that’s didn’t really help. I put in my glasses and everything still feels the same. Do I rest my eyes more for the rest of the night? Does this really damage my eyesight?

I’ve been stressing out because I noticed that my vision is starting to blur; therefore, I’m currently looking for an optometrist. I’m glad you shared this by the way because I never knew that since chlorine us a common household product, it can damage the eyes as well. I am a swimmer, maybe this is one of the reasons why I am experiencing this; that’s why I’d make sure to wear goggles next time.

Shibila says:

Yesterday I went swimming in the hotel pool and had blurred/foggy vision after 1 or 2 hours. Every light had a halo around it which made it difficult to see during the night I bright city light.My eyes looked red and irritated and it was dry and no tear was produced.I used an eye lubricant solution and went to bed. Although the halo has seemed to disappear, i am having sensitivity to light.

santi says:

i have blury vison and i dont know if i need glasses i put in eye drops

Renee Griffith says:

I just went smimming in my daughters pool and when I came out of the pool my eyes were very blurry , foggy, some type of film is covering them. It does not, not feel good at all. Very blurry and dry eyes. I’ve tryed some visine eye drops and it is still blurry foggy. will this affect my vision. what can i do to correct this situation.

Tallulah says:

hi ive got blurry vision and sore eyes. ive experienced this before. the best thing that has worked for me is a wet hand towel and ice on top covering my eys. sleep for a while and then your vision will be back to normal.

Pool lover says:

Why are my ears feeling clogged after I was in the pool for 2 hours. Will it eventually go away or will it stay forever?

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