Urban air pollution and effects on biomarkers of systemic inflammation and coagulation: a panel study in healthy adults.

CONTEXT: Urban particulate air pollution is associated with cardiovascular diseases and mortality, possibly mediated through systemic inflammation and increased blood viscosity. OBJECTIVES: To examine short-term effects of exposure to urban air pollution on blood biomarkers for systemic inflammation and coagulation in a panel of healthy adults living in Gothenburg, Sweden. MATERIALS AND METHODS: The 16 volunteers, all non-smokers, median age 35 years, were called for blood sampling the morning after a day with high levels of urban particulate matter (PM10 > 30 µg/m³) or a day with low levels (PM10 < 15 µg/m³ and NO2 < 35 µg/m³). Associations between exposure to air pollution and each biomarker (C-reactive protein, fibrinogen, serum amyloid A, coagulation factor VIII, plasminogen activator inhibitor-1, p-selectin, soluble intercellular adhesion molecule-1, soluble vascular adhesion molecule-1, Clara cell protein 16 and surfactant protein D) were examined using a linear mixed-effects model. RESULTS: In total, 12 sampling sessions were performed, six after high-pollution and six after low-pollution days, over 21 months. The ratio of air pollution levels between high- and low-pollution days was five for PM10 (median: 49 and 10 µg/m³) and two for NO2 (median: 47 and 24 µg/m³). No significant increase in blood levels of any of the biomarkers were seen after days with high air pollution levels compared with low levels. CONCLUSION: Biomarkers of inflammation and coagulation were not found to be significantly increased in the mornings after days with elevated levels of urban air pollution compared with low levels when performing repeated blood samplings in healthy volunteers.