Pulmonary Epithelial Integrity in Children: Relationship to Ambient Ozone Exposure and Swimming Pool Attendance Birgitta Json Lagerkvist,1 Alfred Bernard,2 Anders Blomberg,3 Erik Bergstrom,4 Bertil Forsberg,1 Karin Holmstrom,5 Kjell Karp,5 Nils-Goran Lundstrom,1 Bo Segerstedt,1 Mona Svensson,1 and Gunnar Nordberg1 1Environmental and Occupational Medicine, Department of Public Health and Clinical Medicine, Umea University, Umea, Sweden; 2Unit of Industrial Toxicology, Catholic University of Louvain, Brussels, Belgium; 3Respiratory Medicine and Allergy, Department of Public Health and Clinical Medicine, 4Paediatrics, Department of Clinical Sciences, and 5Clinical Physiology, Department of Surgical and Peri-operative Sciences, Umea University, Umea, Sweden Abstract Airway irritants such as ozone are known to impair lung function and induce airway inflammation. Clara cell protein (CC16) is a small anti-inflammatory protein secreted by the nonciliated bronchiolar Clara cells. CC16 in serum has been proposed as a noninvasive and sensitive marker of lung epithelial injury. In this study, we used lung function and serum CC16 concentration to examine the pulmonary responses to ambient O3 exposure and swimming pool attendance. The measurements were made on 57 children 10-11 years of age before and after outdoor exercise for 2 hr. Individual O3 exposure was estimated as the total exposure dose between 0700 hr until the second blood sample was obtained (mean O3 concentration/m3 hours) . The maximal 1-hr value was 118 µg/m3 (59 ppb) , and the individual exposure dose ranged between 352 and 914 µg/m3hr. These O3 levels did not cause any significant changes in mean serum CC16 concentrations before or after outdoor exercise, nor was any decrease in lung function detected. However, children who regularly visited chlorinated indoor swimming pools had significantly lower CC16 levels in serum than did nonswimming children both before and after exercise (respectively, 57 ± 2.4 and 53 ± 1.7 µg/L vs. 8.2 ± 2.8 and 8.0 ± 2.6 µg/L ; p < 0.002) . These results indicate that repeated exposure to chlorination by-products in the air of indoor swimming pools has adverse effects on the Clara cell function in children. A possible relation between such damage to Clara cells and pulmonary morbidity (e.g., asthma) should be further investigated. Key words: airway irritants, children, Clara cell protein (CC16) , nitrogen trichloride, ozone, swimming pool. Environ Health Perspect 112:1768-1771 (2004) . doi:10.1289/ehp.7027 available via http://dx.doi.org/ [Online 13 September 2004] Address correspondence to B.J. Lagerkvist, Environmental Medicine, Department of Public Health and Clinical Medicine, Umea University, S-901 87 Umea, Sweden. Telephone: 46-90-7851343. Fax: 46-90-779630. E-mail: Birgitta.Lagerkvist@envmed.umu.se Research nurse M. Backman, Paediatrics, has contributed with excellent work in the practical part of this study. A. Hagenbjork-Gustafsson, the National Institute for Working Life, Umea, performed the ozone measurements. Financial support has been given by the European Commission (HELIOS project, QLK4-1308) , the Swedish Environmental Protection Agency, and Forskningsradet for Miljo, Areella Naringar och Samhalle. The authors declare they have no competing financial interests. Received 12 February 2004 ; accepted 13 September 2004. The full version of this article is available for free in HTML or PDF formats. |