Effects of individual ozone exposure on lung function in the elderly: a cross-sectional study in China

The aim of this study was to assess the acute health effects of individual ozone (O₃) exposure on the respiratory system in the elderly. A total of 40 non-smoking elderly volunteers completed personal 24 h of measurement for O₃ and fine particulate matter (PM_2.5). To assess health effects, we measured the pulmonary function and five inflammatory biomarkers in exhaled breath condensate (EBC), including interleukin-2 (IL-2), interferon-γ (IFN-γ), prostaglandin E₂ (PGE₂), and tumor necrosis factor α/β (TNFα/β). We used the generalized additive model to analyze the association between O₃ and these health effects, after adjusting PM_2.5, BMI, and sex as confounders. As a result, we found a negative correlation between O₃ and forced vital capacity (FVC) or forced expiratory volume-one second (FEV1). With the increasing of O₃ by 10 μg/m³, FVC and FEV1 decreased by 0.13 L (95% CI 0.01, 0.26) and 0.11 L (95% CI 0.02, 0.20), respectively. We found no statistical significance between O₃ and biomarkers in EBC. The results suggested that individual 24-h O₃ exposure was associated with decreased pulmonary function in the elderly.