Association between airborne PM2.5 acute exposure and blood 25-hydroxy vitamin D concentration in children under 3 years old: A retrospective study

The harmful consequences of airborne fine particulate matter (PM 2.5 ) have become a serious public health matter of universal concern, particularly for youngsters. Exposure to PM 2.5 may interfere with vitamin D metabolism in humans. However, the influences of airborne acute PM 2.5 exposure on the blood 25-hydroxy vitamin D [25-OH vitamin D] of young children remains unclear. In the current research, we investigated the links between PM 2.5 acute exposure and plasma 25-OH vitamin D of youngsters who lived in Beijing, China, between April 2020 and September 2022. A total of 1916 children aged from 0.13 to 3.00 years old were enrolled. We collected daily airborne PM 2.5 data and determined the plasma 25-OH vitamin D of children using LC-MS/MS assay. The association between acute PM 2.5 exposure and plasma 25-OH vitamin D was investigated with the generalized linear mixed model and generalized additive model. Our results demonstrated that the acute exposure to airborne PM 2.5 was a linear negative correlation with the plasma 25-OH vitamin D 3 in infants, each 10 μg/m 3 elevate in airborne PM 2.5 on current (lag0), lag1, and lag01 (the moving average concentration) days were related to a 0.139 (95% CI: 0.274–0.004), 0.158 (95% CI: 0.305–0.011) and 0.178 (95% CI: 0.333–0.023) ng/mL decrease in plasma 25-OH vitamin D 3 , respectively. The declining tendency of plasma 25-OH vitamin D 3 remained robust after adjusting the airborne PM 10 and O 3 in the sensitivity analyses. Our study lends credence that the airborne PM 2.5 acute exposure imposed relatively mild but significant reductions in plasma vitamin 25-OH vitamin D 3 in young children. • The effects of acute PM 2.5 exposure on vitamin 25(OH)D remains to be elucidated. • Vitamin 25(OH)D of 1916 children aged under 3 yrs old was measured with LC-MS/MS. • Acute exposure to PM 2.5 was related to the reduction in plasma vitamin 25(OH)D 3 . • Controlling PM 2.5 exposure may reduce its adverse effect on vitamin D metabolism.