1. Helmholtz Zentrum Muenchen; German Research Center for Environmental Health; Institute of Epidemiology I; Neuherberg; Germany
2. Dr von Hauner Children's Hospital; Ludwig-Maximilians-University of Munich; Munich; Germany
3. Department of Pediatrics; Technical University of Munich; Munich; Germany
4. Department of Pediatrics; Marien-Hospital Wesel; Wesel; Germany
5. Institut fuer Umweltmedizinische Forschung; University of Duesseldorf; Duesseldorf; Germany
6. UFZ-Center for Environmental Research; Leipzig; Germany
7. Faculty of Medicine Environmental Medicine & Hygiene; University Leipzig; Leipzig; Germany