1. Key Laboratory of Trace Element Nutrition MOH
2. National Institute for Nutrition and Health
3. Chinese Center for Disease Control and Prevention
4. Beijing 100050
5. PR China
6. Shandong Center for Disease Control and Prevention
7. Jinan 250014
8. China
9. Key Laboratory of Food Safety Risk Assessment of Ministry of Health
10. China National Center for Food Safety Risk Assessment
11. Beijing 100021