Metabolic and Pulmonary Health Effects of Ozone and Black Carbon Exposure in Young Adult Runners

摘要

Physical activity has been shown to promote health and well-being, however, exercising in environments with high level of air pollution can increase the risk of health problems ranging from reduced exercise capacity, high blood pressure to cardiorespiratory impairments. In this crossover study, we investigated the impact of short-term exposure to black carbon (BC) and ozone on metabolic and pulmonary functions among thirty healthy young adult runners after 30-minutes run on a clean and polluted route on separate daysin August 2015 in Hong Kong. Measurements of systolic and diastolic blood pressures, forced vital capacity, forced expiratory volume in 1 second, peak expiratory flow and fractional exhaled nitric oxide were collected pre- and post-run. Real-time ambient concentration of BC was measured at the route, whereas concentration of ozone was obtained from Hong Kong Environmental Protection Department air monitoring station nearest to the running routes. Our runners were on average 20 years old, with mean body mass index of 20.3 kg/m3. Air pollution concentrations were higher in the polluted route than in the clean route, with the highest difference in BC (5,397 ng/m3versus 1,340 ng/m3). In single-pollutant regression models, no significant association was found between air pollution and changes in metabolic or pulmonary biomarkers adjusting for gender, type of route, temperature and relative humidity. However, when adjusting for both BC and ozone simultaneously, an interquartile range increment in BC became statistically significantly associated with increase in systolic blood pressure (17.82; 95% CI: 2.56, 33.09) after running exercise. No significant association was found for ozone upon adjusting for BC. Our finding of BC is consistent with existing literature, while further studies with greater sample size and longer exposure time are needed to investigate the effects of ozone to metabolic/lung functions in runners.