It seems as if a new theory to explain the rise in childhood asthma pops up every week.

According to health columnist Julie Deardorff of the Chicago Tribune, the ‘pool chlorine hypothesis’ asks whether the rise in childhood asthma stems from indoor swimming pools.

Indoor swimming pools give off toxic gases and aerosols, which can be especially harmful to the lungs of small children.

A recent study in Belgium suggests that trichloramine (a chlorine byproduct that gives indoor pools their distinctive odor) is one of the most concentrated air pollutants to which children in developed countries are regularly exposed. When pool chlorine reacts with organic matter like sweat and urine, it produces trichloramine, and the gas is released into the air.

Trichloramine and other chlorine-based chemicals can be associated with airway changes that predispose children to developing asthma and recurrent bronchitis.

If you plan to take your child to an indoor pool, make sure that it's well ventilated!

Alfred Bernard, lead researcher in the Belgian study, says, ‘If there is no strong chlorine smell in the pool hall, there should be no problem with the pool air.’

Just remember, children breathe more often and their lungs are smaller, so they are much more susceptible to respiratory problems stemming from poor indoor air quality.