Among air pollutant concentrations, O<sub>3</sub> in lag-1 (p = 0.017) and lag-2 (p = 0.038), NO<sub>2</sub> in lag-1 (p = 0.015) and lag-2 (p = 0.009), PM<sub>10</sub> in lag-1 (p = 0.012), and PM<sub>2.5</sub> in lag-1 (p = 0.021) and lag-2 (p = 0.032) were significantly different between no PSP and PSP days.