1. Total Healthcare Center Kangbuk Samsung Hospital, Sungkyunkwan University, School of Medicine Seoul Korea
2. Department of Preventive Medicine School of Medicine Kyung Hee University Seoul Korea
3. Ewha Institute of Convergence Medicine Ewha Womans UniversityMokdong Hospital Seoul Korea
4. Department of Occupational and Environment Medicine College of Medicine Ewha Womans University Seoul Korea
5. Department of Pediatrics School of Medicine Kyung Hee University Seoul Korea
6. Department of Occupational and Environmental Medicine, School of Medicine Kyung Hee University Seoul Korea