Effects of physical activity, air pollution, and inhaled dose on lung function in 6-9 year-old children

<bold>Introduction:</bold> Inhaled dose, the product of inspired air and air pollution concentration is a novel approach to study the combined health impacts of physical activity and air pollution. We compared the effects of weekly moderate-to-vigorous physical activity (MVPA), nitrogen dioxide (NO₂) and particulate matter (PM_2.5) concentrations, and inhaled dose (ID_NO₂ and ID_PM_2.5) on lung function. <bold>Methods:</bold> Forced expiratory volume in one second (%FEV₁) and forced vital capacity (%FVC) were measured in 1581 children (838 boys) aged 8.2±1.6 years in the Human Early Life Exposome (HELIX) study. Children’s MVPA was calculated from questionnaires. The NO₂ and PM_2.5 exposures the week prior to spirometry were estimated using land use regression modelling. ID_NO₂ and ID_PM_2.5 were calculated as the product of pol concentration and estimated minute ventilation from MVPA. Using linear regressions, we assessed the main effects of MVPA, pollutant concentrations, IDs, and the interaction effects of MVPA and air pollution exposures on %FEV₁ and %FVC. <bold>Results & Discussion:</bold> MVPA appears to positively affect %FEV₁ and %FVC in children, even when accounting for NO₂ or PM_2.5 exposure concentrations. The effects of ID_NO₂ and ID_PM_2.5 on lung function were similar to those for the main effects of MVPA with adjustment for the pollutant. No interaction effects between MVPA and either NO₂ or PM_2.5 exposure, respectively, were found.