Department of Occupational Medicine, Kaohsiung Municipal Hsiaokang Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan
2.Graduate Institution of Occupational Safety and Health, Kaohsiung Medical University, Kaohsiung, Taiwan
3.Department of Preventive Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan
4.Department of Otolaryngology, Kaohsiung Medical University Hospital, Taiwan
5.Department of Otolaryngology, Kaohsiung Medical University Hospital, Taiwan;Department of Pubic Health, Faculty of Medicine, College of Medicine, Kaohsiung Medical University, Taiwan