Chlorine Is Tied to Rise in Children’s Asthma

Chlorine used in swimming pools may contribute to the surge of childhood asthma in developed countries, Belgian researchers reported in the journal Occupational and Environmental Medicine. Trichloramine, a byproduct of the interaction between chlorine and organic matter in the water, may be the culprit.

In a study of children, they found that regular swimming was associated with the destruction of cellular barriers protecting the deep lung, making them leaky and potentially more vulnerable to the passage of allergens. Among children who swam the most, the damage was similar to that caused by cigarette smoking, they reported.