The question: Infant swimming programs begin at four months of age, but there seem to be some notions "floating around" that link children swimming in chlorinated pools to an increased chance of developing asthma later in life. Is there any validity to this? At what age is it safe for kids to start swimming?
The answer: A number of scientific studies over the past decade have suggested that there is a link between children swimming in chlorinated pools and the development of allergies and asthma. One of the more frequently cited is from Belgium, published online in 2009 in Pediatrics.
Children were followed in terms of the duration of swimming indoors compared with outdoors; tests were conducted on their lung function and blood. The study concluded that swimming in chlorinated water put them at heightened risk for asthma (eight times more likely) and hay fever (three to six times more likely).
The thought is that wen chlorine interacts with organic material such as sweat, urine and hair, it creates byproducts such as trichloramine and methane. The vapours, which may help allergens enter the body through damaged respiratory membranes and surfaces, are inhaled particularly deeply by swimmers during intense exertion.
Not all children are equally susceptible. Based on their genetic backgrounds, some kids may be more sensitive to chlorine byproducts. The duration of exposure is also important. Some of the children in the Belgium study swam for more than 500 hours over a few years and, compared with kids who swam less, they were more prone to develop asthma.
If you're concerned about the level of chlorine in a pool, watch for side effects such as eye and skin irritation.
There are some classes that teach babies water safety – as young as six months (see babyswimming.com). Aquatic classes for babies have become more popular recently, most likely because parents want young children to at least be able to float, hoping it may prevent drowning.
But the official recommendations by pediatric organizations suggest that, developmentally, a child is ready for swimming lessons by age 4.
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