1. Research Center for Precision Prevention and Control of Occupational Hazards, School of Public Health, Xinxiang Medical University, Xinxiang, Henan 453003, P.R. China
2. Department of Occupational and Environmental Health, School of Public Health, North China University of Science and Technology, Tangshan, Hebei 063000, P.R. China
3. Key Laboratory of Birth Regulation and Control Technology, National Health Commission of China, Maternal and Child Care Hospital of Shandong Province, Shandong University, Jinan, Shandong 250001, P.R. China
4. Institute of Toxicology, College of Preventive Medicine, Army Medical University, Chongqing 400038, P.R. China
5. Department of Occupational and Environmental Health, School of Public Health, Zhengzhou University, Zhengzhou, Henan 450001, P.R. China