1. Department of Laboratory Medicine, Division of Clinical Chemistry and Pharmacology, Lund University, Lund, Sweden;
2. La Isla Network, Washington, DC, USA;
3. School of Public Health and Community Medicine, Unit of Occupational and Environmental Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden;
4. Unit of Occupational Medicine, Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden;
5. University of Massachusetts Lowell, Lowell, Massachusetts, USA;
6. Sahlgrenska University Hospital, Gothenburg, Sweden