* Corresponding authors

^a Department of Hygiene Toxicology, School of Public Health, Zunyi Medical University, Zunyi, 563000 Guizhou, China

^b Department of Orthopaedic Surgery, Affiliated Hospital of Zunyi Medical University, Zunyi, 563003 Guizhou, China
E-mail: xin.wang@zmu.edu.cn
Fax: +86-851-2860 8903
Tel: +86 136 3928 8558

^c Key Laboratory of Maternal & Child Health and Exposure Science of Guizhou Higher Education Institutes, Zunyi Medical University, Zunyi, 563000 Guizhou, China

^d Guizhou Provincial Key Laboratory of Medicinal Biotechnology in Colleges and Universities, Zunyi Medical University, Zunyi, 563000 Guizhou, China