1. Institute for Endemic Fluorosis Control, Center for Endemic Disease Control, Chinese Center for Disease Control and Prevention, National Health Commission Key Laboratory of Etiology and Epidemiology, Harbin Medical University, Harbin 150081, China
2. Heilongjiang Provincial Key Laboratory of Trace Elements and Human Health & Key Laboratory of Etiology and Epidemiology, Education Bureau of Heilongjiang Province, Harbin Medical University, Harbin 150081, China
3. Institute for Kashin-Beck Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Harbin Medical University, Harbin 150081, China