Eye irritation after swimming is often attributed to high chlorine levels. However, the primary culprits behind burning eyes and the distinct “chlorine” smell are not chlorine itself, but chemical compounds called chloramines. While chlorine is a necessary disinfectant, it is not the main cause of discomfort. Understanding the true reasons can help swimmers enjoy the water more comfortably.
The Actual Cause of Eye Irritation
The primary cause of burning eyes and the strong “chlorine” smell in pools is not chlorine itself, but chemical compounds called chloramines. Chloramines form when chlorine reacts with nitrogen-containing substances introduced by swimmers, such as sweat, urine, skin cells, and cosmetics.
These compounds, also known as combined chlorine, are less effective at sanitizing the water than free chlorine. They are responsible for the unpleasant odor and irritation. Chloramines are volatile compounds that can turn into a gas and irritate mucous membranes like those in the eyes and respiratory tract. A strong “chlorine” smell indicates insufficient free chlorine to manage waste, leading to a buildup of these irritating chloramines.
Other Contributors to Discomfort
While chloramines are a major factor, other elements in pool water can also contribute to eye irritation. The pH level of the pool water plays a significant role in swimmer comfort. The human eye has a pH of approximately 7.4. When pool water pH deviates significantly from this range, either too low (acidic) or too high (alkaline), it can cause burning, redness, and discomfort. An ideal pool pH range is generally between 7.2 and 7.8.
High levels of total dissolved solids (TDS) in pool water can also contribute to irritation. TDS includes various organic and inorganic substances that accumulate over time. If TDS levels exceed approximately 3,000 parts per million (ppm), the water can become cloudy and irritating to the eyes. Other contaminants, such as dirt, debris, lotions, and sunscreens, can react with chlorine to form additional irritants or contribute to water imbalance, exacerbating eye discomfort.
Preventing and Relieving Eye Discomfort
Minimizing eye irritation involves proactive steps for both pool owners and swimmers. For pool owners, proper maintenance is essential, including regular testing and balancing of water chemistry. Consistently monitoring and adjusting chlorine and pH levels ensures the water remains within comfortable and safe parameters, reducing chloramine formation and maintaining eye comfort. Ensuring good filtration and circulation also helps remove contaminants before they can react with chlorine.
Swimmers can reduce their exposure to irritants by taking a few simple precautions. Showering before entering the pool helps rinse off sweat, body oils, and other personal contaminants that react with chlorine to form chloramines. Avoiding urination in the pool is important, as urine is a major source of nitrogen compounds that contribute to chloramine formation. Wearing swim goggles provides a physical barrier, protecting the eyes from direct contact with pool water.
For immediate relief after swimming, rinsing eyes with fresh water or a sterile saline solution can help flush out irritants. Lubricating eye drops can soothe dry or irritated eyes by re-establishing the protective tear film. Applying a cool compress can alleviate discomfort and redness. If irritation persists, seeking advice from an eye care professional is recommended.