Associations of blood lead levels with multiple genotoxic biomarkers among workers in China: A population-based study

Tuanwei Wang; Yuting Tu; Kan Wang; Shiyang Gong; Guanghui Zhang; Yunxia Zhang; Yu Meng; Tongshuai Wang; Anqi Li; Junpeng Cui; Huan Liu; Weifeng Tang; Jing Xi; Yiyi Cao; Yang Luan; David C Christiani; William Au; Zhao-Lin Xia

doi:10.1016/j.envpol.2020.116181

Associations of blood lead levels with multiple genotoxic biomarkers among workers in China: A population-based study

Environ Pollut. 2020 Nov 30:273:116181. doi: 10.1016/j.envpol.2020.116181. Online ahead of print.

Authors

Tuanwei Wang¹, Yuting Tu¹, Kan Wang¹, Shiyang Gong¹, Guanghui Zhang², Yunxia Zhang¹, Yu Meng¹, Tongshuai Wang¹, Anqi Li¹, Junpeng Cui², Huan Liu², Weifeng Tang³, Jing Xi³, Yiyi Cao³, Yang Luan³, David C Christiani⁴, William Au⁵, Zhao-Lin Xia⁶

Affiliations

¹ Department of Occupational Health & Toxicology, School of Public Health, Shanghai Medical College of Fudan University, 130 Dongan Road, Shanghai 200032, China.
² Department of Occupational & Environmental Health, School of Public Health, Xinxiang Medical University, 601 Jinsui Road, Xinxiang 453003, Henan Province, China.
³ School of Public Health, Hongqiao International Institute of Medicine, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China.
⁴ Environmental Medicine and Epidemiology Program, Department of Environmental Health, Harvard University TH Chan School of Public Health, Boston, MA, USA.
⁵ George Emil Palade University of Medicine, Pharmacy, Science and Technology, Targu Mures, Romania, And University of Texas Medical Branch, Galveston, TX, USA.
⁶ Department of Occupational Health & Toxicology, School of Public Health, Shanghai Medical College of Fudan University, 130 Dongan Road, Shanghai 200032, China. Electronic address: zlxia@shmu.edu.cn.

PMID: 33508628
DOI: 10.1016/j.envpol.2020.116181

Abstract

Carcinogenic effects from low doses of lead (Pb) exposure to populations have been suspected but not concluded. Therefore, a large-scale cross-sectional study was conducted by us to investigate genotoxic effects from Pb exposure during 2016-2018 in North China. Blood lead levels (BLLs) and cumulative blood lead levels (CBLLs) were measured. Multiple relevant biomarkers were used to assess genotoxicity of Pb: mitochondrial DNA copy number (mtDNAcn, n = 871), Comet Tail Intensity (n = 872), γ-H2AX (n = 345), relative telomere length (rTL, n = 757), micronuclei (MN, n = 934) and phosphatidylinositol glycan class A mutation (PIG-A, n = 362). The BLL data show right-skewed distribution, with increase of the median (P₂₅, P₇₅) from 17.4 (8.9, 26.4) μg/dl in 2016 to 18.5 (10.5, 27.2) μg/dl in 2017, and to 20.8 (11.3, 31.0) μg/dl in 2018. Multivariate regression analyses show that mtDNAcn was non-linearly associated with BLLs or CBLLs, i.e. decreased at low levels but increased at the higher levels. Comet and Micronuclei data show positive dose-response relationships with BLLs as well as CBLLs. γ-H2AX data show an overall increased trend with BLLs while rTL data show a shortening trend. No associations were found for PIG-A mutation with Pb exposure. Our findings indicate that current low dose exposure to Pb can still cause health hazards to occupational populations, and the mechanism may be via the induction of DNA & chromosome damage rather than via the mutagenesis pathway.

Keywords: Comet; Lead exposure; Micronuclei; PIG-A mutation; Relative telomere length; mtDNAcn.