Junchao Duan12, Yongbo Yu12, Yang Yu12, Yang Li12, Peili Huang12, Xianqing Zhou12, Shuangqing Peng3 and Zhiwei Sun12*
1 School of Public Health, Capital Medical University, Beijing 100069, P.R. China
2 Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing 100069, P.R. China
3 Institute of Disease Control and Prevention, Academy of Military Medical Sciences, Beijing 100071, P.R. China