Air pollution modeling and exposure assessment during pregnancy in the French Longitudinal Study of Children (ELFE).

Abstract We developed a nation-wide exposure model to NO 2 , PM 10 and PM 2.5 at a fine spatial and temporal resolution for France in order to study air pollutants exposure during pregnancy for the French Longitudinal Study of Children (ELFE). The exposure to air pollutants was estimated daily for years 2010 and 2011 by combining three simulation models at the national and regional scale (CHIMERE) and at the local urban scale (ADMS-Urban or SIRANE). The spatial resolution was 4 km for the national scale model, 3–4 km for regional models and from 10 to 200 m for urban-scale models. We developed a confidence index (from 0 to 10) based on the target plot to identify the best model to estimate exposure for a given address, year and pollutant. Air pollution exposure during pregnancy was then estimated using each modeling scale for the 17,427 women participating in the ELFE cohort. We described the exposure of the women during different time windows of pregnancy using each of the three models and using the most suitable model as estimated by the confidence index. The exposure estimates obtained from the three models were quite similar and highly correlated (spearman correlation between 0.64 and 0.96), especially for the national and regional models. For NO 2 and PM 10 predicted by the urban models, the minimum values were lower and the maximum values and the variability were higher, compared to the regional and national models. The averaged confidence indexes were comprised between 5.6 and 8 depending on the pollutant, year and exposure model considered. The best confidence index was observed for urban modeling (10) and the lowest for the regional modeling (0). In average during pregnancy, using the most suitable model, women were exposed to 21 μg/m3 for NO 2 , 16 μg/m3 for PM 2.5 and 24 μg/m3 for PM 10. To our knowledge, this is the first study combining three modeling tools available at different scales to estimate NO 2 , PM 10 and PM 2.5 concentrations at a fine spatial and temporal resolution over a large geographical area. The confidence index provides guidance in the choice of the exposure model. These exposure estimates will be used to investigate potential effects of air pollutants on the pregnant woman health and on health of the fetus and development of the child. Highlights • NO 2 , PM 10 and PM 2.5 exposure during pregnancy for the ELFE mother-child cohort. • Fine spatial (10–200 m at the urban scale) and temporal resolution for France. • Combination of three dispersion models at the national, regional, and local scale. • Confidence index to choose the best exposure model. • Mean pregnancy exposure was 21 μg/m3 for NO 2 , 16 μg/m3 for PM 2.5 , 24 μg/m3 for PM 10. [ABSTRACT FROM AUTHOR]