1. Department of Environmental Health Research, Seoul Medical Center, Seoul, Korea.
2. Department of Pediatrics, Hallym Sacred Heart Hospital, Hallym University College of Medicine, Anyang, Korea.
3. Department of Pediatrics, Inje University Haeundae Paik Hospital, Busan, Korea.
4. Department of Pediatrics, Inje University Sanggye Paik Hospital, Seoul, Korea.
5. Department of Pediatrics, CHA University School of Medicine, Seongnam, Korea.
6. Department of Pediatrics, Dankook University College of Medicine, Cheonan, Korea.
7. Asan Institute for Life Sciences, University of Ulsan College of Medicine, Seoul, Korea.
8. Department of Pediatrics, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Korea.
9. Department of Environmental Health, University of Cincinnati College of Medicine, Cincinnati, Ohio.
10. Department of Preventive Medicine, Dankook University College of Medicine, Cheonan, Korea.
11. Department of Pediatrics, Childhood Asthma Atopy Center, Environmental Health Center, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.