1. Department of Chronic Diseases and Environmental Epidemiology, University of Kuopio Kuopio, Finland
2. National Institute of Public Health and Environmental Protection, Bilthoven, and the Department of Epidemiology and Public Health, University of Kuopio Kuopio, Finland
3. Agricultural University Wageningen, the Netherlands; and the Department of Applied Chemistry and Microbiology, University of Kuopio Kuopio, Finland
4. Division of Nutrition, University of Helsinki, and the Department of Epidemiology and Health Promotion, University of Kuopio Kuopio, Finland
5. National Public Health Institute Helsinki, and the Department of Environmental Epidemiology, University of Kuopio Kuopio, Finland
6. National Public Health Institute, and the Department of Community Health and General Practice, University of Kuopio Kuopio, Finland