Several recently published studies are fueling speculation — and concern — about whether chlorine disinfection byproducts are linked to respiratory illnesses, including asthma.
|ASTHMA RISK In a recent study, researchers found a direct relationship between the number of hours teenage participants logged in outdoor pools and the prevalence of asthma.|
The first, published in the journal Acta Pædiatrica,used data from the Norwegian Institute of Public Health’s Norwegian Mother and Child Study. It identified a possible connection between infant swimming and increased risk of breathing problems. The study included 30,000
participants, 25 percent of whom were enrolled in swim programs
between birth and 6 months of age.
Forty-seven percent of infant swimmers experienced
incidents of wheezing or tightness of the chest, between 6 and 18
months. These infants also were from mothers with asthma and
allergies. By comparison, only 44 percent of nonswimmer infants
from the same group experienced incidents of respiratory
difficulties from ages 6 to 18 months.
The results show baby swimming may be related to
later breathing problems, but further investigation is needed, said
Wenche Nystad, department director of the NIPH’s Division of
Epidemiology and a lead author of the study.
The second study looked at pools and the risks of
asthma and allergies in adolescents. Published in the European Respiratory
Journal, Dr. Alfred Bernard of Catholic University of
Louvain, Brussels, Belgium, and his team examined 847 students with
an average age of 15. They found that asthma risk increases
consistently with the number of hours the teens spent in outdoor
Findings indicate that those with the highest
attendance at outdoor pools were approximately five times more
likely to suffer from asthma than those who had never been in an
outdoor pool. Bernard and his team noted that markers indicating a
predisposition to respiratory problems also are a factor.