Association between long-term exposure to fine particulate matter from sand dust storms and small airway dysfunction:...

Despite growing concern on the health effects of dust-sourced fine particulate matter (dust PM_2.5), especially in the context of climate change, but the respiratory health effect has not been well characterized. Investigating the impact of dust PM_2.5 on small airway dysfunction (SAD) is important for early prevention, since SAD represents an early stage of airway obstruction. This study evaluated the dose-response associations and effect modifications of long-term dust PM_2.5 exposure with risks of SAD on a national scale. SAD was identified based on lung function data from the China Pulmonary Health Study (N = 50,326). An interquartile range (IQR, 5.76 μg/m³) increment in long-term dust PM_2.5 concentration was associated with higher risk of SAD (Odds ratio [OR]:1.18, 95 % confidence interval [CI]:1.08, 1.28) and SAD without airflow obstruction (OR: 1.24, 95 % CI: 1.10, 1.39). Long-term dust PM_2.5 exposure was significantly associated with decrease in pre- and post-bronchodilator lung function. Individuals with lower levels of education were found to be more vulnerable. This finding provided much-needed evidence on why and when air pollution leads to irreversible airway obstruction, calling for greater awareness on the harm of fine dust particle on early-stage lung impairment. Studies on the countermeasures of respiratory hazard caused by SDS are warranted.