Qianqian MA ; Huacheng WANG ; Souqing WANG ; Min LÜ ; Jinlong ZHANG ; Miaomiao WANG ; Lei HAN ; Hengdong ZHANG
Chinese Journal of Industrial Hygiene and Occupational Diseases 2014;32(10):749-751
Humans ; Occupational Exposure ; Occupational Health ; Risk Factors ; Sanitation