1. Department of Public Health and Clinical Medicine Sustainable Health, Umeå University Umeå Sweden
2. Department of Medicine, Division of Occupational and Environmental Medicine University of California San Francisco San Francisco California USA
3. Occupational and Environmental Medicine, School of Public Health and Community Medicine, Institute of Medicine, Sahlgrenska Academy University of Gothenburg Gothenburg Sweden
4. Department of Occupational and Environmental Medicine Sahlgrenska University Hospital Gothenburg Sweden