1. Centre for Research in Environmental Epidemiology (CREAL), Barcelona, Spain
2. CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain
3. Universitat Pompeu Fabra, Barcelona, Spain
4. Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland
5. University of Basel, Basel, Switzerland
6. Team of Environmental Epidemiology Applied to Reproduction and Respiratory Health, Institute Albert Bonniot, National Institute of Health and Medical Research (INSERM), U823, Grenoble, France
7. Division of Environmental Epidemiology, Institute for Risk Assessment Sciences, Utrecht University, Utrecht, the Netherlands
8. Bradford Institute for Health Research, Bradford Teaching Hospitals NHS Trust, Bradford, United Kingdom
9. School of Health Studies, University of Bradford, Bradford, United Kingdom