title: Hydrogen peroxide in exhaled air of healthy children: reference values.
abstract: An increased content of hydrogen peroxide (H2O2), a marker of inflammation, has been described in the condensate of exhaled air from adults and children with inflammatory lung disorders, including asthma. However, the normal range of [H2O2] in the exhaled air condensate from healthy children has not been established. Therefore, the aim of this study was to determine the reference range of exhaled [H2O2] in healthy school-aged children. Ninety-three healthy nonsmoking children (48 female and 45 male, mean age 10 yrs, range 8-13 yrs), with a negative history for allergy, eczema or respiratory disease and with a normal lung function, participated. Exhaled air condensate was examined fluorimetrically for the presence of H2O2. In addition, the reproducibility of [H2O2] within subjects and between days and the stability of [H2O2] during storage at -20 degrees C were assessed. The median [H2O2] in the exhaled air condensate of all children was 0.13 microM, with a 2.5-97.5% reference range of <0.01-0.48 microM. No significant difference existed between males and females. There was no correlation between exhaled [H2O2] and age or lung function. Repeated [H2O2] measurements on 2 consecutive days showed satisfactory within-subject reproducibility and [H2O2] in stored samples remained stable for at least 1 month at -20 degrees C. In conclusion, this study provides reference data for exhaled hydrogen peroxide in a large group of healthy children. The observed levels were lower than those reported previously for healthy adults and were independent of age, sex and lung function.
authors.affiliation: Dept of Paediatrics, Erasmus University and University Hospital/Sophia Children's Hospital, Rotterdam, The Netherlands.
authors.forename: Q
authors.initials: Q
authors.lastname: Jöbsis
authors.forename: H C
authors.initials: HC
authors.lastname: Raatgeep
authors.forename: S L
authors.initials: SL
authors.lastname: Schellekens
authors.forename: W C
authors.initials: WC
authors.lastname: Hop
authors.forename: P W
authors.initials: PW
authors.lastname: Hermans
authors.forename: J C
authors.initials: JC
authors.lastname: de Jongste
mesh_terms: D001944:Breath Tests; D002648:Child; D005260:Female; D006801:Humans; D006861:Hydrogen Peroxide / Q000032:analysis*; D008297:Male; D012016:Reference Values; D015203:Reproducibility of Results; D012129:Respiratory Function Tests
chemical_list: D006861:Hydrogen Peroxide