1. Department of Child and Adolescent Health, School of Public Health, China Medical University, Shenyang 110122, Liaoning, China
2. Department of Pediatrics, The Fourth Affiliated Hospital of China Medical University, Shenyang 110032, Liaoning, China
3. Key Laboratory of Environmental Stress and Chronic Disease Control and Prevention, Ministry of Education, China Medical University, Shenyang 110122, Liaoning, China
4. Environmental Health Department of Xiqing District Center for Disease Control and Prevention, Tianjin 300380, China
5. Department of Rheumatology, Shengjing Hospital of China Medical University, Shenyang 110022, Liaoning, China