Outdoor Swimming Pools and the Risks of Asthma and Allergies during Adolescence

¹ Dept of Public Health, Catholic University of Louvain, Belgium

^* To whom correspondence should be addressed. E-mail: bernard{at}toxi.ucl.ac.be.

	Abstract

Exposure to indoor chlorinated swimming pools can be detrimental to the airways of swimmers and increase asthma risks but it is unknown whether these effects concern outdoor pools.

We studied 847 secondary school adolescents who had attended at a variable rate residential or non-residential outdoor chlorinated pools. Main outcomes were ever asthma (physician-diagnosed at any time), current asthma (ever asthma under medication and/or with exercise-induced bronchoconstriction), elevated exhaled nitric oxide and aeroallergens-specific IgE in serum.

The prevalences of ever and current asthma increased with the lifetime number of hours spent in outdoor pools by up to four and eight times, respectively, among adolescents with the highest attendance (>500 hours) and a low exposure to indoor pools (<250 hours) (all P for trend <0.001). Odds for asthma were significantly increased among adolescents with total serum IgE above 25 kIU·l^-1, on average by one to two units for each 100 hours-increase in pool attendance. Use of residential outdoor pools was also associated with higher risks of elevated exhaled nitric oxide and sensitization to cat or house-dust mite allergens.

Outdoor chlorinated pools attendance is associated with higher risks of asthma, airways inflammation and some respiratory allergies.

This article has been cited by other articles:

				A. Bernard, M. Nickmilder, C. Voisin, and A. Sardella Impact of Chlorinated Swimming Pool Attendance on the Respiratory Health of Adolescents Pediatrics, October 1, 2009; 124(4): 1110 - 1118. [Abstract] [Full Text] [PDF]

				K-H. Carlsen Asthma, airway inflammation and epithelial damage in elite athletes Eur. Respir. J., April 1, 2009; 33(4): 713 - 714. [Full Text] [PDF]