A lot of people get scared of opening their eyes underwater because they fear the usual burning sensation and redness in the eyes that usually follows. However, it’s not the chlorine that causes those sensations; it’s something much worse: fecal matter.
“The irritating sensation (in the eyes) is the chemical produced by an interaction between chlorine and urine, sweat, dirt, etc.,” said Dr. Michael Schwandt, the deputy medical health officer for the Saskatoon Health Region. “It’s related to chlorine, but it’s not chlorine itself. It’s the interaction with other things that’s making the chloramines that causes the typical irritation.”
The old story about dyes in the pool that change colour when someone whizzes in it is actually a myth. According to the National Swimming Pool Foundation, red eyes are actually a better indicator. While the intensity of burning eyes is different for everyone, the fact that they’re burning at all is still a clear sign of contaminants.
According to Schwandt, the chlorine on its own actually causes little or no irritation and has very little odour. Even that strong “pool smell” that most people are familiar with is caused by those chemical reactions.
For these reasons, health professionals (and everyone else) recommend that people with diarrhea or other illnesses avoid getting into pools. Those who do choose to get in should rinse themselves under a shower thoroughly first. And because accidents still happen, people who enter pools are advised not to swallow the water.
“It’s possible for infections to be transmitted through pool water because it takes time for the chlorine to do its job of neutralizing the bacteria,” said Schwandt. “The amount of time required to eliminate bacteria is related to the amount of chlorine.”
This is why the ventilation in pools is also important. Schwandt says the chemicals tend to hover just above the water, so adequate air movement means there is less time for people to be expose to it when swimming and playing.
Despite all this, Schwandt says there’s still very little risk of acquiring illnesses by going swimming. It’s still a great way to get recreation and exercise. If a person is still concerned about irritation and/or infection, the best means of avoiding it would be to wear goggles and refrain from swallowing any water.
“Overall, it can be a matter of individual reaction and judgment to know how and when to limit that exposure,” said Schwandt. “If everyone can take steps to reduce the risk, it’ll be good for everyone.”
