1Department of Preventive Medicine, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan, Republic of Korea
2Department of Preventive Medicine, University of Ulsan College of Medicine, Seoul, Republic of Korea
3Environmental Health Center, University of Ulsan College of Medicine, Ulsan, Republic of Korea
4Department of Occupational and Environmental Medicine, Ulsan University Hospital, University of Ulsan College of Medicine, 877 Bangeojinsunhwan-doro, Dong-gu, Ulsan, 44033 Republic of Korea
5Department of Atmospheric Sciences, Pusan National University, Busan, Republic of Korea
© The Author(s). 2018
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