The stinging sensation in eyes after swimming is often attributed to too much chlorine. However, this irritation is primarily caused by a chemical reaction in the pool water, involving factors beyond just the disinfectant itself.
The Real Reason for Eye Irritation
Eye irritation after swimming is primarily caused by chloramines, not the free chlorine added to sanitize the water. Chloramines form when free chlorine reacts with organic compounds introduced into the pool by swimmers, such as sweat, urine, body oils, cosmetics, and skin cells.
These irritating compounds create the strong “chlorine smell” often associated with pools, signaling that chlorine is reacting with contaminants. A well-maintained pool with sufficient free chlorine should have little odor. Chloramines also reduce the effectiveness of free chlorine, making it less efficient at killing germs.
Beyond Just Burning
Beyond a burning sensation, eye exposure to pool water can lead to other symptoms like redness, itchiness, excessive tearing, and temporary blurred vision. These symptoms arise from the disruption of the eye’s natural tear film, a protective layer that keeps the eye lubricated and shields it from irritants.
These irritations are generally mild and resolve shortly after exiting the pool. However, prolonged exposure to high concentrations of chloramines or an improper pH balance can lead to more persistent discomfort. The pool’s pH level should ideally be similar to human tears, between 7.2 and 7.8, to minimize irritation.
Protecting Your Eyes in the Pool
Several steps can help protect your eyes in the pool.
For Swimmers
Wear properly fitted swim goggles to prevent direct contact between pool water and eyes, reducing exposure to irritating chemicals.
Rinse eyes with fresh water or a sterile saline solution immediately after swimming to wash away lingering pool chemicals.
For Pool Owners
Maintaining proper water chemistry is important in preventing chloramine formation. Regularly testing and balancing the pool’s pH and free chlorine levels ensures the disinfectant works efficiently and reduces irritant buildup. Periodically “shocking” the pool involves adding a higher dose of chlorine or an oxidizer to break down existing chloramines, restoring water quality. Encouraging swimmers to shower before entering the pool also helps by removing organic matter like sweat and body oils, which react with chlorine to form chloramines.