Children's Health and Environment Program, Child Health Research Centre, The University of Queensland, South Brisbane, QLD 4101, Australia; Environmental Health and WASH, Health Systems and Population Studies Division, icddr,b, Dhaka 1212, Bangladesh.
Rural Health Research Institute, Charles Sturt University, Orange, NSW 2800, Australia.
Toxicology. 2024 Dec;509:153978. doi: 10.1016/j.tox.2024.153978. Epub 2024 Oct 24.
Electronic waste (e-waste) contains hazardous elements such as lead (Pb), cadmium (Cd), mercury (Hg), and other toxic elements that pose significant health risks to the population directly exposed. We recruited 199 e-waste recycling workers and 104 non-exposed workers in Bangladesh and analyzed heavy metals in blood and hair, as well as hematological and cardiovascular parameters including, blood lipids and blood pressure. We fitted quantile regression models at 0.5 quantile to evaluate the impact of blood Pb, Cd, and total hair Hg (THg) on hematological and cardiovascular parameters and the role of oxidative DNA damage (8-OHdG as a biomarker) in mediatin the relationship between exposures and outcomes. Exposed workers had elevated median blood Pb (11.89 vs. 3.63 µg/dL), moderate blood Cd (1.04 vs. 0.99 µg/L), and lower level of THg (0.38 vs. 0.57 ppm) in hair than non-exposed workers. Adjusted estimates showed that Pb was positively associated with red blood cell (RBC), eosinophil count, eosinophil percentage; and negatively associated with mean platelet volume (MPV), platelet large cell ratio (P-LCR) and platelet volume distribution width (PDW) (all p≤0.05). Cd was only associated with 0.57 units increase in red blood cell distribution width (RDW) percentage (95 % CI: 0.18, 0.95). In cardiovascular outcomes, Pb was associated with 1.42 units decrease in triglyceride, 1.58 units increase in low-density lipoprotein (LDL), 0.07 units increase in LDL/HDL and 0.49 units increase in systolic blood pressure (all p≤0.05). No associations were observed between THg and hematological or cardiovascular parameters. Urinary 8-OHdG concentrations were lower, and it did not mediate exposure-outcome relationships (all p≥0.05). Our data imply that e-waste exposure impairs hematological parameters, blood lipids, and blood pressure secondary to elevated Pb levels and poses a threat to exposed individuals. As such, continuous monitoring in longitudinal studies is warranted to assess the dose-response relationship and identify effective control measures.
电子垃圾（e-waste）含有铅（Pb）、镉（Cd）、汞（Hg）等有害元素以及其他有毒元素，这些元素直接对接触人群的健康构成重大威胁。我们在孟加拉国招募了 199 名电子废物回收工人和 104 名非接触工人，并分析了他们血液和头发中的重金属含量，以及包括血脂和血压在内的血液学和心血管参数。我们在 0.5 分位数处拟合了分位数回归模型，以评估血液 Pb、Cd 和总发汞（THg）对血液学和心血管参数的影响，以及氧化 DNA 损伤（8-OHdG 作为生物标志物）在介导暴露与结果之间关系中的作用。与非接触工人相比，暴露工人的血液 Pb 中位数（11.89 对 3.63µg/dL）较高，血液 Cd 中位数（1.04 对 0.99µg/L）中度升高，头发中的 THg 中位数（0.38 对 0.57ppm）水平较低。调整后的估计表明，Pb 与红细胞（RBC）、嗜酸性粒细胞计数、嗜酸性粒细胞百分比呈正相关；与平均血小板体积（MPV）、血小板大细胞比（P-LCR）和血小板体积分布宽度（PDW）呈负相关（均 p≤0.05）。Cd 仅与红细胞分布宽度（RDW）百分比增加 0.57 个单位相关（95%CI：0.18，0.95）。在心血管结局方面，Pb 与甘油三酯降低 1.42 个单位、低密度脂蛋白（LDL）增加 1.58 个单位、LDL/HDL 增加 0.07 个单位和收缩压增加 0.49 个单位相关（均 p≤0.05）。THg 与血液学或心血管参数之间无关联。尿 8-OHdG 浓度较低，且不介导暴露-结局关系（均 p≥0.05）。我们的数据表明，电子废物暴露会因 Pb 水平升高而损害血液学参数、血脂和血压，对接触人群构成威胁。因此，需要进行纵向研究以连续监测，以评估剂量-反应关系并确定有效的控制措施。
