1. Department of Medical Informatics, Biometry and Epidemiology; Friedrich-Alexander University Erlangen-Nürnberg; D-91054 Erlangen Germany
2. Occupational Diseases Department; University Hospital of Centre of Paris COCHIN, AP-HP; 75014 Paris France
3. Laboratoire Santé Publique et Environnement, EA 4064; Paris Descartes University; Sorbonne Paris Cité 75014 Paris France
4. Department of Dermatology; University of Witten/Herdecke and Klinikum Dortmund (formerly); 44137 Dortmund Germany
5. Department of Dermatology, Hospital del Mar; Institut Mar d'Ínvestigacions Mediques Universitat Autònoma; 08003 Barcelona Spain
6. Department of Dermatology, Environmental Medicine and Health Theory; University of Osnabrueck; 49076 Osnabrueck Germany
7. Laboratoire de Dermatochimie ILB, CNRS; University of Strasbourg; F-67081 Strasbourg France
8. Institute of Environmental Medicine, Karolinska Institutet; SE-17177 Stockholm Sweden
9. St John's Institute of Dermatology, St Thomas' Hospital; London SE1 7EH UK
10. Department of Dermato-Allergology, National Allergy Research Centre, Gentofte Hospital; University of Copenhagen; 2900 Hellerup Denmark