1. Department of Public Health and Clinical Medicine, Division of Occupational and Environmental Medicine/the OLIN Unit, Umeå University , Umeå, Sweden
2. Department of Health Sciences, Luleå University , Luleå, Sweden
3. Department of Public Health and Clinical Medicine, Division of Medicine/the OLIN Unit, Umeå University , Umeå, Sweden
4. Krefting Research Centre, Institute of Medicine, University of Gothenburg , Gothenburg, Sweden