1. Department of Occupational Health and Occupational Medicine; School of Public Health, Southern Medical University; Guangzhou Guangdong PR China
2. Department of Physical Factors and Occupational Health; Guangdong Province Hospital for Occupational Disease Prevention and Treatment; Guangzhou Guangdong PR China
3. Department of Scientific Education; Guangdong Provincial Maternal and Child Health Hospital; Guangzhou Guangdong PR China