1. Institute for Community Medicine, University Medicine Greifswald, Greifswald, Germany.
2. Institutes of Clinical Chemistry and Laboratory Medicine, University Medicine Greifswald, Greifswald, Germany.
3. Institutes of Hygiene and Environmental Medicine, University Medicine Greifswald, Greifswald, Germany.
4. Institutes of Epidemiology and Social Medicine, University Medicine Greifswald, Greifswald, Germany.