Irva Hertz-Picciotto,1 Rebecca James Baker2 (posthumous), Poh-Sin Yap,1 Miroslav Dostál,3 Jesse P. Joad,4 Michael Lipsett,5 Teri Greenfield,1 Caroline E.W. Herr,1,6 Ivan Benes,7 Robert H. Shumway,8 Kent E. Pinkerton,9 and Radim Srám3
1Department of Public Health Sciences, University of California, Davis, California, USA; 2Department of Epidemiology, University of North Carolina, Chapel Hill, North Carolina, USA; 3Laboratory of Genetic Ecotoxicology, Institute of Experimental Medicine, AS CR and Health Institute of Central Bohemia, Prague, Czech Republic; 4Department of Pediatrics, University of California, Davis, California, USA; 5Department of Epidemiology and Biostatistics, University of California, San Francisco, California, USA; 6Institute of Hygiene and Environmental Medicine, University of Giessen, Giessen, Germany; 7Health Institute Usti n.L., Branch Teplice, Czech Republic; 8Department of Statistics, University of California, Davis, California, USA; 9Department of Rheumatology, Allergy and Clinical Immunology, University of California, Davis, California, USA
Abstract
Background: Few studies of air pollutants address morbidity in preschool children. In this study we evaluated bronchitis in children from two Czech districts: Teplice, with high ambient air pollution, and Prachatice, characterized by lower exposures.
Objectives: Our goal was to examine rates of lower respiratory illnesses in preschool children in relation to ambient particles and hydrocarbons.
Methods: Air monitoring for particulate matter < 2.5 µm in diameter (PM2.5) and polycyclic aromatic hydrocarbons (PAHs) was conducted daily, every third day, or every sixth day. Children born May 1994 through December 1998 were followed to 3 or 4.5 years of age to ascertain illness diagnoses. Mothers completed questionnaires at birth and at follow-up regarding demographic, lifestyle, reproductive, and home environmental factors. Longitudinal multivariate repeated-measures analysis was used to quantify rate ratios for bronchitis and for total lower respiratory illnesses in 1,133 children.
Results: After adjustment for season, temperature, and other covariates, bronchitis rates increased with rising pollutant concentrations. Below 2 years of age, increments in 30-day averages of 100 ng/m3 PAHs and of 25 µg/m3 PM2.5 resulted in rate ratios (RRs) for bronchitis of 1.29 [95 % confidence interval (CI) , 1.07–1.54] and 1.30 (95% CI, 1.08–1.58) , respectively ; from 2 to 4.5 years of age, these RRs were 1.56 (95% CI, 1.22–2.00) and 1.23 (95% CI, 0.94–1.62) , respectively.
Conclusion: Ambient PAHs and fine particles were associated with early-life susceptibility to bronchitis. Associations were stronger for longer pollutant-averaging periods and, among children > 2 years of age, for PAHs compared with fine particles. Preschool-age children may be particularly vulnerable to air pollution–induced illnesses.
Key words: air pollution, bronchitis, children's health, infant, particulate matter, PM2.5, PAHs, polycyclic aromatic hydrocarbons, respiratory illness, volatile organic compounds. Environ Health Perspect 115: 1510–1518 (2007) . doi:10.1289/ehp.9617 available via http://dx.doi.org/ [Online 22 May 2007]
http://www.ehponline.org/docs/2007/9617/abstract.html
