[Air Pollution Characteristics and Jogger Inhalation Exposure in Typical Running Area of Beijing]

To investigate the exposure to major air pollutants of runners while running in Beijing, the concentrations of PM_2.5, CO, O₃, and NO₂ were constantly monitored at typical park running areas (Tiantan Park and Olympic Sports Center), roadside running areas (Qianmen East Street and Yongding Inner Street), and a background area (Dinglin) during April, June, and October of 2016 and in January 2017. The concentration variation characteristics for the pollutants in different areas and at different times were analyzed. Using a numerical model of human respiratory exposure, 102 joggers were studied, as was the temporal-spatial variation of inhalation dose of pollutants. At typical running areas, the concentrations of CO, NO₂, and PM_2.5 were relatively higher in winter, whereas the concentrations of O₃ were higher in spring and summer. The concentrations of CO, NO_2, and PM_2.5 were lower in the afternoon (16:00-18:00), whereas the concentrations of O₃ were lower in the morning (06:00-08:00) and evening (18:00-20:00). There was a linear correlation between concentrations roadside to those in nearby parks, as the concentrations of CO roadside were generally consistent with those in parks (c_road/c_park=1.01, R²=0.93), the concentrations of NO₂ and PM_2.5 roadside were higher than those in parks (c_road/c_park were 0.56 and 1.19, respectively), and the concentrations of O₃ roadside were lower than those in parks (c_road/c_park=0.74, R²=0.97). During moderate or higher pollution conditions, 92% of joggers halted outdoor activities, 62.7% chose to jog in parks, 66.7% chose to jog at night, and 64.7% of joggers had single run mileages of 10-20 km. When people chose to jog in the afternoon and evening, the inhalation of CO, NO₂, and PM_2.5 were relatively lower, whereas the inhalation of O₃ was higher. During spring and summer, night running after 20:00 reduced the O₃ inhalation dose. Running roadside led to higher inhalation of CO, NO₂, and PM_2.5 than that in parks; however, O₃ inhalation was lower.