1. Department of Dermatology, Environmental Medicine and Health Theory; University of Osnabrück; Osnabrück Germany
2. Department of Dermatology; Ernst von Bergmann General Hospital; Teaching Hospital Charité University Medicine Berlin; Potsdam Germany
3. Laboratory for Analytical Chemistry; Department of Chemistry and Biochemistry; Faculty of Food Technology and Biotechnology; University of Zagreb; Zagreb Croatia
4. Departments of Respiratory Medicine and Experimental Immunology; Academic Medical Center; University of Amsterdam; Amsterdam The Netherlands
5. Department of Dermato-Allergology; Gentofte Hospital; University of Copenhagen; Hellerup Denmark
6. Department of Dermatology, Venereology, and Allergology; University Medical Center Göttingen; Georg August University; Göttingen Germany
7. Lower Saxony Institute of Occupational Dermatology; University of Osnabrück and University Medical Center Göttingen; Osnabrück/Göttingen Germany
8. Coronel Institute for Occupational Health; Academic Medical Center; University of Amsterdam; Amsterdam The Netherlands