Background: Accumulating evidence from laboratory animal and human studies suggests that air pollution exposure during pregnancy affects cognitive and psychomotor development in childhood.
Methods: We analyzed data from 6 European population-based birth cohorts—GENERATION R (The Netherlands), DUISBURG (Germany), EDEN (France), GASPII (Italy), RHEA (Greece), and INMA (Spain)—that recruited mother–infant pairs from 1997 to 2008. Air pollution levels—nitrogen oxides (NO2, NOx) in all regions and particulate matter (PM) with diameters of <2.5, <10, and 2.5–10 μm (PM2.5, PM10, and PMcoarse, respectively) and PM2.5 absorbance in a subgroup—at birth addresses were estimated by land-use regression models, based on monitoring campaigns performed primarily between 2008 and 2011. Levels were back-extrapolated to exact pregnancy periods using background monitoring sites. Cognitive and psychomotor development was assessed between 1 and 6 years of age. Adjusted region-specific effect estimates were combined using random-effects meta-analysis.
Results: A total of 9482 children were included. Air pollution exposure during pregnancy, particularly NO2, was associated with reduced psychomotor development (global psychomotor development score decreased by 0.68 points [95% confidence interval = −1.25 to −0.11] per increase of 10 μg/m3 in NO2). Similar trends were observed in most regions. No associations were found between any air pollutant and cognitive development.
Conclusions: Air pollution exposure during pregnancy, particularly NO2 (for which motorized traffic is a major source), was associated with delayed psychomotor development during childhood. Due to the widespread nature of air pollution exposure, the public health impact of the small changes observed at an individual level could be considerable.
From the aCenter for Research in Environmental Epidemiology, Barcelona, Spain; bHospital del Mar Research Institute, Barcelona, Spain; cSpanish Consortium for Research on Epidemiology and Public Health (CIBERESP), Instituto de Salud Carlos III, Madrid, Spain; dInserm, Team of Environmental Epidemiology Applied to Reproduction and Respiratory Health, U823, Grenoble, France; eUniversity Grenoble-Alpes, Institut Albert Bonniot, Grenoble, France; fDepartment of Epidemiology Lazio Regional Health Service, Rome, Italy; gUniversity of Valencia, Valencia, Spain; hCenter for Public Health Research (CSISP)/FISABIO, Valencia, Spain; iInstitute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands; jDepartment of Social Medicine, University of Crete, Heraklion, Greece; kInserm, Centre for research in Epidemiology and Population Health (CESP), U1018, Epidemiology of Diabetes, Obesity and Kidney Disease: Lifelong Approach Team, Paris, France; lUniversity Paris-Sud, UMRS 1018, France; mCentre for Environmental Policy, Imperial College London, United Kingdom; nBiomedical Research Center, University of Granada; Granada, Spain; oLaboratory of Medical Investigations, San Cecilio University Hospital; Granada, Spain; pPreventive Medicine and Public Health, University of Oviedo, Oviedo, Spain; qDepartment of Child and Adolescent Psychiatry/Psychology, Erasmus Medical Centre–Sophia Children’s Hospital, Rotterdam, The Netherlands; rThe Generation R Study, Erasmus Medical Centre, Rotterdam, The Netherlands; sDepartment of Epidemiology, Erasmus Medical Centre, Rotterdam, The Netherlands; tIUF-Leibniz Research Institute for Environmental Medicine, Düsseldorf, Germany; uNational School of Public Health, Athens, Greece; vEpidemiology and clinical research unit, Hopital Beaujon, APHP, Paris, France; wINSERM, UMR S953, Epidemiological Research Unit on Perinatal Health and Women’s and Childrens’ Health, Paris, France; xDepartment of Preventive Medicine and Public Health, University of Basque Country (EHU/UPV), San Sebastian, Spain; yBioDonostia Health Research Institute, San Sebastian, Spain; zDepartment of Social Psychology and Behavioral Sciences Methodology, University of Basque Country (EHU/UPV), San Sebastian, Spain; aaATMO Poitou-Charentes, La Rochelle, France; bbDanish Cancer Society Research Center, Copenhagen, Denmark; ccEnvironmental Chemical Processes Laboratory (ECPL), University of Crete, Heraklion, Greece; ddDepartment of Psychiatry, Erasmus Medical Centre, Rotterdam, The Netherlands; eeHelmholtz Zentrum München, German Research Centre for Environmental Health, Institute of Epidemiology I, Neuherberg, Germany; ffLudwig-Maximilians-University of Munich, Institute of Medical Informatics, Biometrics and Epidemiology, Neuherberg, Germany; ggDepartment of Public Health, Academic Medical Centre, University of Amsterdam, Amsterdam, The Netherlands; hhThe ABCD Study Group, Amsterdam, The Netherlands; iiDepartment of Hygiene, Social and Environmental Medicine, Ruhr-University Bochum, Bochum, Germany; jjJulius Center for Health Sciences and Primary Care, University Medical Center Utrecht, The Netherlands; kkInstitute of Environmental Medicine, Karolinska Institutet, Solna, Sweden; and llPompeu Fabra University, Barcelona, Spain.
Submitted 31 July 2013; accepted 11 February 2014; posted 16 July 2014.
The authors report no conflicts of interest.
ESCAPE Project. The research leading to these results has received funding from the European Community’s Seventh Framework Program (FP7/2007-2011) under grant agreement number: 211250. Funding sources for the individual projects are listed in the Acknowledgments section at the end of this article.
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Correspondence: Mònica Guxens, Centre for Research in Environmental Epidemiology, Carrer Dr. Aiguader 88, 08003-Barcelona, Spain. E-mail: firstname.lastname@example.org.