1. Department of Occupational and Environmental Health, School of Public Health, Xi’an Jiaotong University Health Science Center, 76 Yanta West Road, Yanta District, Xi’an 710061, China
2. Key Laboratory of Environment and Genes Related to Diseases (Xi’an Jiaotong University), Ministry of Education, Xi’an 710061, China
3. Key Laboratory for Disease Prevention and Control and Health Promotion of Shaanxi Province, Xi’an 710061, China
4. Key Laboratory of Trace Elements and Endemic Diseases in Ministry of Health, Xi’an 710061, China