Airway oxidative stress and inflammation markers in exhaled breath from children are linked with exposure to black carbon

• Published in: Environment international Vol. 73; pp. 440 - 446
• Main Authors: De Prins, Sofie, Dons, Evi, Van Poppel, Martine, Int Panis, Luc, Van de Mieroop, Els, Nelen, Vera, Cox, Bianca, Nawrot, Tim S., Teughels, Caroline, Schoeters, Greet, Koppen, Gudrun
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.12.2014; Elsevier
• Subjects: Air; Air Pollutants - analysis; Air Pollutants - toxicity; Air pollution; Air. Soil. Water. Waste. Feeding; Airway inflammation; Biological and medical sciences; Biomarkers; Biomarkers - metabolism; Child; Children; Dinoprost - analogs & derivatives; Dinoprost - analysis; Environment. Living conditions; Environmental Exposure; Environmental pollutants toxicology; Exhalation; Exhaled breath condensate; Female; Humans; Inflammation Mediators - analysis; Interleukin-1beta - analysis; Land use regression; Male; Medical sciences; Nitric Oxide - analysis; Oxidative Stress; Particulate Matter - analysis; Public health. Hygiene; Public health. Hygiene-occupational medicine; Respiratory System - chemistry; Soot - analysis; Soot - toxicity; Toxicology; Belgium; Europe; Biomarkers; Land use regression; Air pollution; Children; Airway inflammation; Exhaled breath condensate; Human; Expired air; Oxidative stress; Carbon black; Biological marker; Land use plan; Exposure; Inflammation; Combustion product; Epidemiology; Respiratory tract; Suspended particle; Health and environment; Condensates; Regression model; Child; Public health; Charcoal
• ISSN: 0160-4120; 1873-6750
• DOI: 10.1016/j.envint.2014.06.017

The current study aimed at assessing the associations between black carbon (BC) exposure and markers for airway inflammation and oxidative stress in primary school children in a Western European urban area. In 130 children aged 6–12 years old, the fraction of exhaled nitric oxide (FeNO), exhaled breath condensate (EBC) pH, 8-isoprostane and interleukin (IL)-1β were measured in two seasons. BC concentrations on the sampling day (2-h average, 8:00–10:00AM) and on the day before (24-h average) were assessed using measurements at a central monitoring site. Land use regression (LUR) models were applied to estimate weekly average BC exposure integrated for the time spent at home and at school, and seasonal average BC exposure at the home address. Associations between exposure and biomarkers were tested using linear mixed effect regression models. Next to single exposure models, models combining different BC exposure metrics were used. In single exposure models, an interquartile range (IQR) increase in 2-h BC (3.10μg/m3) was linked with a 5.9% (95% CI: 0.1 to 12.0%) increase in 8-isoprostane. FeNO increased by 16.7% (95% CI: 2.2 to 33.2%) per IQR increase in 24-h average BC (4.50μg/m3) and by 12.1% (95% CI: 2.5 to 22.8%) per IQR increase in weekly BC (1.73μg/m3). IL-1β was associated with weekly and seasonal (IQR=1.70μg/m3) BC with respective changes of 38.4% (95% CI: 9.0 to 75.4%) and 61.8% (95% CI: 3.5 to 153.9%) per IQR increase in BC. An IQR increase in weekly BC was linked with a lowering in EBC pH of 0.05 (95% CI: −0.10 to −0.01). All associations were observed independent of sex, age, allergy status, parental education level and meteorological conditions on the sampling day. Most of the associations remained when different BC exposure metrics were combined in multiple exposure models, after additional correction for sampling period or after exclusion of children with airway allergies. In additional analyses, FeNO was linked with 24-h PM10 levels, but the effect size was smaller than for BC. 8-Isoprostane was not linked with either 2-h or 24-h concentrations of PM2.5 or PM10. BC exposure on the morning of sampling was associated with airway oxidative stress while 24-h and weekly exposures were linked with airway inflammation. •130 schoolchildren aged 6–12 years old were examined in two seasons.•Airway inflammation (FeNO, EBC pH, IL-1β) and oxidative stress (EBC 8-isoprostane)•BC estimated using LUR (week, season) and measured at a central site (2-h and 24-h)•24-h BC associated with FeNO, weekly BC associated with FeNO and IL-1β in EBC•2-h BC exposure associated with 8-isoprostane in EBC