If you swim underwater with your eyes open, you might want to stop doing so. No matter what type of water you're in, there are threats to your peepers' health left and right. Irritation caused by chemicals and particles in water may not do permanent damage; however, serious bacterial infections, contact lens problems and debris can cause long-lasting negative effects. Protect your eyes underwater by wearing goggles.
Pools
Chlorine is used in pools to keep it clean from the outside environment and from swimmers' germs, but if enough chlorine were put in the pool to kill all the germs, it would be too acidic for our skin -- not to mention our eyes. That means there are still germs and compounds floating around in the water, usually bacteria (though not all bacteria is bad) and oils from swimmers' bodies, which can cause eye irritation and even bacterial infection if you swim with open eyes. If there's too much chlorine in a pool, the chlorine will irritate your eyes and cause itchiness. Pools with the right amount of chlorine have a pH between 7.2 and 7.8, the natural pH of our bodies, so skin and eye irritation are minimal. You may want to check the pH of the pool before opening your eyes underwater. In indoor pools, if there's little or no air circulation in the building, contaminants called chloramines build up in the air and water and can cause eye irritation. This can be avoided by opening doors and windows and using fans to increase air circulation over the water.
Ocean
The salty water of the ocean keeps it relatively clean, but stings your eyes when you open them in the water. Another threat is debris particles, which can scratch the cornea of your eye. If you plan on opening your eyes in the ocean, it's a good idea to wear goggles.
Lakes and Ponds
Freshwater swimming can be dangerous for open eyes because of the risk of bacterial infection. Lakes, ponds, streams and rivers don't have chlorine or salt to clean them, so they can be a hub for viruses and bacteria that can enter the body through your eyes. Open eyes can also be easily exposed to debris particles in fresh water.
Contact Lenses
Several problems arise from wearing contact lenses in any type of water without protecting them with goggles. You may think your contacts are protecting your eyes from debris and bacteria in the water. However, the pores in the lenses designed to allow your eyes to absorb oxygen collect particles and microscopic bacteria, which can potentially cause eye damage or infection. Avoid swimming in chlorinated pools with your eyes open while wearing contacts; chlorine collects in the pores of the lenses much as particles and bacteria do, causing irritation and redness. If you rub or scratch your eyes while swimming, your lenses can scratch your cornea if they're caked with chlorine and debris particles.
