Short-term effects of the chemical components of fine particulate matter on pulmonary function: A repeated panel study among adolescents.

The effects of the chemical components of fine particulate matter (PM) have been drawing attention. However, information regarding the impact of low PM concentrations is limited. Hence, we aimed to investigate the short-term effects of the chemical components of PM on pulmonary function and their seasonal differences in healthy adolescents living on an isolated island without major artificial sources of air pollution. A panel study was repeatedly conducted twice a year for one month every spring and fall from October 2014 to November 2016 on an isolated island in the Seto Inland Sea, which has no major artificial sources of air pollution. Daily measurements of peak expiratory flow (PEF) and forced expiratory volume in 1 s (FEV) were performed in 47 healthy college students, and the concentrations of 35 chemical components of PM were analyzed every 24 h. Using a mixed-effects model, the relationship between pulmonary function values and concentrations of PM components was analyzed. Significant associations were observed between several PM components and decreased pulmonary function. Among the ionic components, sulfate was strongly related to decreases in PEF and FEV (-4.20 L/min [95 % confidence interval (CI): -6.40 to -2.00] and - 0.04 L [95 % CI: -0.05 to -0.02] per interquartile range increase, respectively). Among the elemental components, potassium induced the greatest reduction in PEF and FEV. Therefore, PEF and FEV were significantly reduced as the concentrations of several PM components increased during fall, with minimal changes observed during spring. Several chemical components of PM were significantly associated with decreased pulmonary function among healthy adolescents. The concentrations of PM chemical components differed by season, suggesting the occurrence of distinct effects on the respiratory system depending on the type of component.