1. Center for Endemic Disease Control, Chinese Center for Disease Control and Prevention Harbin Medical University Harbin People's Republic of China
2. National Health Commission & Education Bureau of Heilongjiang Province, Key Laboratory of Etiology and Epidemiology Harbin Medical University Harbin People's Republic of China
3. Heilongjiang Provincial Key Laboratory of Trace Elements and Human Health Harbin Medical University Harbin People's Republic of China
4. Key Lab of Environment and Health, School of Public Health Xuzhou Medical University Xuzhou China