1Department of Occupational and Environmental Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
2Occupational Safety and Health Research Institute, KOSHA, Republic of Korea, Ulsan, Republic of Korea
3Department of Occupational and Environmental Medicine, Dankook University College of Medicine, Cheonan, 201 Manghyang-ro, Dongnam-gu, Cheonan-si, Chungcheongnam-do 31116 Republic of Korea JFIF d d Ducky d qhttp://ns.adobe.com/xap/1.0/