1. Department of Occupational and Environmental Medicine, Ewha Womans University Mokdong Hospital, Seoul, Korea.
2. Graduate Program in System Health Science and Engineering, Ewha Womans University, Seoul, Korea.
3. Department of Preventive Medicine, College of Medicine, Ewha Womans University, Seoul, Korea.
4. Department of Preventive Medicine, College of Medicine, Seoul National University, Seoul, Korea.
5. Department of Preventive Medicine, Dankook University College of Medicine, Cheonan, Korea.
6. Department of Occupational and Environmental Medicine, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan, Korea.
7. Environmental Health Research Department, National Institute of Environmental Research, Incheon, Korea.
8. Department of Occupational and Environmental Medicine, College of Medicine, Ewha Womans University, Seoul, Korea.