Encouraging children to take to swimming is alright. But there is a flip side too.
Swimming in chlorinated pools could actually increase a child's risk of developing asthma. The traditional advice that swimming is beneficial for young asthmatics could be off the mark, a new study seems to indicate.
Pediatrics, a leading journal, reported last week that children who swam in indoor chlorinated pools during their early years have higher rates of asthma and breathing problems later on than those who did not.
This was blamed on airway damage from breathing in various chlorination fumes.
One of the potentially harmful gases was named as trichloramine - or nitrogen trichloride - which can result from chlorine reacting with ammonia or swimmers' urine or sweat.
Indoor pools are thought to exacerbate the problem by trapping fumes inside, thus forcing swimmers to inhale higher concentrations of the chemicals.
The former Olympic swimmer Samantha Riley began swimming as a child to help combat her asthma.
Riley, who now runs a chain of indoor pools in Queensland, doubts that her condition was caused by pool exposure.
"It has always been my understanding that swimming is of benefit rather than a cause of asthma,'' she said.
"I would hate to stop parents sending their children to learn to swim because it's a life-saving skill, especially in our climate.''
Riley's son Lucas Fydler, 2, also has asthma. He has been to hospital four times in the past month, but his condition is improving.
"He has inherited my lungs,'' Riley said.
Other famous swimmers to suffer from asthma include Susie Maroney, Dawn Fraser, Matthew Dunn and Grant Hackett.
The European study, which involved 341 schoolchildren, pointed out that asthma rates were up to 10 times higher in developed English-speaking nations such as Australia than most southern and eastern countries.
"Our data suggest that infant swimming practice in chlorinated indoor swimming pools is associated with airways changes that, along with other factors, seem to predispose children to the development of asthma and recurrent bronchitis,'' the study's authors concluded.
Developed countries also tend to have more chlorinated swimming pools.
Professor Peter van Asperen, head of respiratory medicine at The Children's Hospital at Westmead, Australia, said parents shouldn't panic at the findings.
"It is an important issue to be aware of,'' he said.
"There may be potential for chemicals to affect the risk of respiratory diseases but the message for Australians is there is much more risk from indoor pools than outdoor pools.''
He said swimming was traditionally recommended for asthmatic children because it tended not to trigger exercise-induced attacks as much as other sports, such as running.
Mosman mum Caroline Jane encourages her two young children to swim but generally avoids indoor pools.
"I had asthma as a child and I remember it always used to get worse when I went swimming at the pool,'' she said.
"My children are big swimmers - they normally swim at our (home) pool or at the beach.
"I think limited chlorine pool exposure is best.''
Her children Saskia, 4, and Hugo, 2, do not have asthma.