Airborne Endotoxin Is Associated with Respiratory Illness in the First 2 Years of Life Robert Dales,1 David Miller,1 Ken Ruest,2 Mireille
Guay,1 and Stan Judek1 1Air Health Effects Division, Health Canada, Ottawa, Ontario, Canada; 2Research
Division, Canada Mortgage and Housing Corporation, Ottawa, Ontario, Canada Abstract To determine the influence of endotoxin on the incidence of acute respiratory illness during the first 2 years of life, we carried out a longitudinal follow-up study, beginning at birth, of 332 children born in Prince Edward Island, Canada. We measured 5-day averaged air endotoxin in the homes of children, whose parents provided information by daily symptom diaries and twice-monthly telephone contact for up to 2 years. Endotoxin concentration was 0.49 ± 3.49 EU/m3 (geometric mean ± geometric SD) , and number of annualized illness episodes was 6.83 ± 2.80 (mean ± SD) . A doubling of the air endotoxin concentration was associated with an increase of 0.32 illness episodes per year (p = 0.0003) , adjusted for age, year of study, breast-feeding, environmental tobacco smoke, child care attendance, indoor temperature, and income. Indoor mold surface area and fungal ergosterol were not significantly associated with endotoxin. Airborne endotoxin appears to be a risk factor for clinically symptomatic respiratory illnesses during the first 2 years of life independent of indoor fungus. Key words: bacteria, children, endotoxin, housing, respiratory illness. Environ Health Perspect 114:610-614 (2006) . doi:10.1289/ehp.8142 available via http://dx.doi.org/ [Online 3 November 2005]
Address correspondence to R. Dales, Ottawa Hospital (General Campus) , 501 Smyth Rd., Box 211, Ottawa, Ontario K1H 8L6, Canada. Telephone: (613) 737-8198. Fax: (613) 739-6266. E-mail: rdales@ottawahospital.on.ca This work is supported by Health Canada, Canada Mortgage and Housing Corporation, Prince Edward Island Reproductive Care Program, Prince Edward Island Medical Society, Carleton University, and Prince Edward Island Department of Health and Social Services. The authors declare they have no competing financial interests. Received 23 March 2005 ; accepted 3 November 2005. The full version of this article is available for free in HTML or PDF formats. |