A new study shows competitive swimmers training at indoor chlorinated swimming pools may have lung changes like what is seen in people with mild asthma.
Researchers compared data from more than 20 elite swimmers in
Canada with 10 healthy people, and 10 mild asthmatics. Tissue
samples from the swimmers showed similarities with those with
asthma, although there is no evidence those changes lead to actual
According to a report published by Reuters, “the research
team, led by Valerie Bougault at the Lille 2 University of Health
and Law in France, found that tissue samples from swimmers’
lungs had nearly six times as many immune cells associated with
asthma and allergies as the lung tissue of healthy subjects, a
similar amount to what was found in the group with mild
Changes may be the result of inhaling disinfection byproducts, or
some other factor. The study appears in the Journal of Allergy
and Clinical Immunology.