1. Occupational Medicine; Finnish Institute of Occupational Health; Topeliuksenkatu 41 a A, 00250 Helsinki Finland
2. Unit of Occupational Medicine, Department of Medicine and Public Health; University of Trieste; Via della Pietà 19, 34129 Trieste Italy
3. Department of Dermatology; The Leeds Teaching Hospitals NHS Trust; Harehills Lane, Leeds LS7 4SA UK
4. Department of Allergology and Environmental Health; Nofer Institute of Occupational Medicine; 8 Teresy Street, 91-348 Lodz Poland
5. Department of Dermatology; University Allergy Centre, University Hospital Carl Gustav Carus, Technical University Dresden; Fetscherstraße 74, D-01307 Dresden Germany
6. Department of Dermatology; University Hospital Erlangen; Ulmenweg 18, D-91054 Erlangen Germany
7. Department of Dermatology; Environmental Medicine and Health Theory, University of Osnabrueck; Sedanstrasse 115, 49069 Osnabrueck Germany
8. Information Network of Departments of Dermatology (IVDK); University of Göttingen; von-Sieboldstr. 3, D-37075 Göttingen Germany
9. Department of Medical Informatics, Biometry and Epidemiology; University of Erlangen/Nürnberg; Waldstr. 6, D-91054 Erlangen Germany