1. Center for Research in Environmental Epidemiology (CREAL), Dr Aiguader 88, 08003 Barcelona, Spain, Catalan Institute for Research and Advanced Studies (ICREA), 08010 Barcelona, Spain, Institute of Environmental Analysis and Water Research, IDAEA, CSIC, C/ Jordi Girona, 18, 08034 Barcelona, Spain, and National School of Public Health, Institute of Health Carlos III, C/ Sinesio Delgado 8, 28029 Madrid, Spain