Department of Occupational and Environmental Health, School of Public Health, Shandong Second Medical University, Weifang, Shandong Province, China.
Department of Environmental Health, College of Preventive Medicine, Army Medical University, Chongqing, China.
Ecotoxicol Environ Saf. 2024 Sep 15;283:116796. doi: 10.1016/j.ecoenv.2024.116796. Epub 2024 Aug 1.
Previous studies reported that lead (Pb) exposure induced adverse health effects at high exposure concentrations, however, there have been limited data on sensitivity comparisons among different health outcomes at low blood Pb levels.
To compare sensitivity between blood parameters and a genotoxic biomarker among workers exposed to low blood Pb levels (< 20 µg/dl), and to estimate a benchmark dose (BMD).
Pb-exposed workers were recruited from a lead-acid storage battery plant. Their blood lead levels (BLLs) were measured. Blood parameters and micronuclei (MN) frequencies were determined. Multivariate linear or Poisson regression was used to analyze relationships between blood parameters or MN frequencies with BLLs. Two BMD software were used to calculate BMD and its 95 % lower confidence limit (BMDL) for BLLs.
The median BLL for 611 workers was 10.44 µg/dl with the 25th and 75th percentile being 7.37 and 14.62 µg/dl among all participants. There were significantly negative correlations between blood parameters and BLLs. However, MN frequencies correlated positively with BLLs (all P<0.05). Results from the two BMD software revealed that the dichotomous model was superior to the continuous model, and the BMDL for BLL derived from red blood cell (RBC) was 15.11 µg/dl, from hemoglobin (HGB) was 8.50 µg/dl, from mean corpuscular hemoglobin (MCH) was 7.87 µg/dl, from mean corpuscular hemoglobin concentration (MCHC) was 3.98 µg/dl, from mean corpuscular volume (MCV) was 11.44 µg/dl, and from hematocrit (HCT) was 6.65 µg/dl. The conservative BMDL obtained from the MN data was 7.52 µg/dl.
Our study shows that low dose Pb exposure caused decrease of blood parameters and increase of MN frequencies. The genotoxic biomarker was more sensitive than most blood parameters. BMDLs for BLL derived from MN frequencies and the red blood cell indicators should be considered as new occupational exposure limits. Our results suggest that MN assay can be considered as a part of occupational health examination items.
先前的研究报告表明，铅（Pb）暴露在高暴露浓度下会对健康产生不良影响，然而，在低血铅水平下，不同健康结果之间的敏感性比较数据有限。
比较暴露于低血铅水平（<20μg/dl）的工人的血液参数和遗传毒性生物标志物之间的敏感性，并估计基准剂量（BMD）。
从一家铅酸蓄电池厂招募了铅暴露工人。测量他们的血铅水平（BLLs）。测定血液参数和微核（MN）频率。采用多元线性或泊松回归分析 BLLs 与血液参数或 MN 频率之间的关系。使用两种 BMD 软件计算 BMD 及其 95%置信下限（BMDL）的 BLL。
611 名工人的中位 BLL 为 10.44μg/dl，所有参与者的 25 百分位和 75 百分位分别为 7.37μg/dl 和 14.62μg/dl。血液参数与 BLL 之间存在显著负相关。然而，MN 频率与 BLL 呈正相关（均 P<0.05）。两种 BMD 软件的结果表明，二项式模型优于连续模型，来自红细胞（RBC）的 BLL 衍生的 BMDL 为 15.11μg/dl，来自血红蛋白（HGB）的为 8.50μg/dl，来自平均红细胞血红蛋白（MCH）的为 7.87μg/dl，来自平均红细胞血红蛋白浓度（MCHC）的为 3.98μg/dl，来自平均红细胞体积（MCV）的为 11.44μg/dl，来自血细胞比容（HCT）的为 6.65μg/dl。来自 MN 数据的保守 BMDL 为 7.52μg/dl。
我们的研究表明，低剂量 Pb 暴露会导致血液参数降低和 MN 频率增加。遗传毒性生物标志物比大多数血液参数更敏感。来自 MN 频率和红细胞指标的 BLL 衍生的 BMDL 应被视为新的职业接触限值。我们的结果表明，MN 测定可以作为职业健康检查项目的一部分。
