"Swimming in chlorinated pools may increase the risk of a child getting asthma and respiratory allergies like hay fever, according to a Belgian study.

Researchers from the Catholic University of Louvain in Brussels, Belgium, found that teenagers who spent more than 100 hours swimming in chlorinated pools were up to six times more at risk of having asthma than other teens.

'The impact of these chemicals on the respiratory health of children and adolescents appears to be much more important -- at least by a factor of five -- than that associated with secondhand smoke,' toxicology professor Alfred Bernard told Reuters Health."

Megan Brooks reports for Reuters September 14, 2009. [2]