Parathyroid hormone mediates the adverse impact of air pollution exposure on serum 25-hydroxyvitamin D: A nationwide cross-sectional study in China

Maintaining normal levels of 25-hydroxyvitamin D [25(OH)D] and parathyroid hormone (PTH) is crucial for preserving skeletal health. However, evidence regarding the associations of exposure to air pollution with serum 25(OH)D and PTH were limited and ambiguous. Hence, the objective of this cross-sectional study was to systematically evaluate the association between air pollution (particulate matter ≤ 2.5 μm [PM