Application of a hierarchical Bayesian model for air pollution prediction in Poland and its association with neurodevelopmental outcomes in children

Background/Aim: Air pollution has been associated to adverse health effects. Poland is one of the most polluted countries in Europe in terms of air quality, with levels exceeding the maximum values established by the UE for several pollutants, including PM10 and PM2.5. This study aims to assess whether air pollution exposures during vulnerable periods (pregnancy, early childhood) affects cognitive/psychomotor development of school-age children. Methods: Hourly levels from air pollutants (PM10, PM2.5, NO2, O3) for the prenatal period (2006-2008) was obtained from both the European air quality database (EEA) and Polish institutions. Health data was collected from the Polish Mother and Child Cohort prospective study conducted in Poland since 2007, with around 400 pregnant women and their children followed up until the age of 7 years. Neurodevelopmental outcomes were assessed through the Strengths and Difficulties Questionnaire and the Intelligence and Development Scales. Spatial prediction of air pollution levels in a 100km radius around the geolocation where pregnant women lived during a 3-years period was performed using a hierarchical Bayesian spatiotemporal model. Afterwards, multivariate regression models between the predicted air pollution levels and neurodevelopmental outcomes in 7-year old children were applied, including different approaches to account for sex-specific effects. Results: Median predicted concentrations of PM10, PM2.5, NO2 and O3 at 91 different locations were 19.6 μg/m3, 16.1 μg/m3, 8.4 μg/m3 and 71.7 μg/m3, respectively. Prenatal exposures to O3 were associated with poorer scores on Hyperactivity/Inattention, specifically in boys. Conversely, PMs and NO2 were associated with poorer scores on Fluid IQ and Total Cognition, specially in girls. Conclusions: The present study suggests that air pollution exposures during the prenatal period might have an impact on children’s development. Due to the diversity of mechanisms involved in child’s neurodevelopment, further studies are required in order to elucidate which are the most critical periods of exposure.