About the Authors
Department of Occupational and Environmental Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
Ministry of Education Key Lab of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
Division of Respiratory Disease Studies, National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention, Morgantown, West Virginia, United States of America
Department of Applied Epidemiology, Institute for Occupational Safety and Health, German Social Accident Insurance (IFA), Sankt Augustin, Germany
Daye Iron Mine Hospital, Wuhan Iron and Steel Corporation, Huangshi, Hubei, China
Jingdezhen Health Bureau, Jingdezhen, Jiangxi, China
The authors have declared that no competing interests exist.
Analyzed the data: WC YL HW SW TW. Wrote the first draft of the manuscript: WC YL. Contributed to the writing of the manuscript: WC YL EH YS TW. ICMJE criteria for authorship read and met: WC YL HW EH YS LS XZ SW FB FH JC TW. Agree with manuscript results and conclusions: WC YL HW EH YS LS XZ SW FB FH JC TW. Initiated and designed the study: WC FH JC. Established the databases: WC YL HW SW LS XZ. Contributed to the interpretation of data and results: EH YS FB.