Yang Hong, Zhang Hengdong, Zhou Qianqian, Gong Wei, Zhu Baoli, Li Wenchao, Zhou Yang
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi. 2015 Jun;33(6):403-8.
To investigate the lead exposure, its effects, and the relationships between biomarkers of susceptibility in the workers with low-level occupational lead exposure, and to explore its sensitivity and practical value to evaluate the health hazard.
The concentrations of lead fume and lead dust in workplaces of a lead acid storage battery enterprise in Jiangsu Province, China, were measured by occupational health monitoring method. The blood samples of 233 workers with occupational lead exposure and 76 non-occupational lead exposure were collected to measure the blood lead (Pb-B) level using graphite furnace atomic absorption spectrometry (GFAAS), the zinc Protoporphyrin (ZPP) level with blood fluorescence assay, and the delta-aminolevulinic acid dehydratase (ALAD) concentration by a spectrophotometer, and to determine the gene polymorphism of ALAD with TaqMan real-time polymerase chain reaction. At the same time, their urine samples were collected to measure urine lead (Pb-U) concentration with GFAAS and delta-aminolevulinic acid (ALA-U) concentration with a spectrophotometer. The correlations between the above indices were analyzed by multiple linear regression method.
The concentration of lead fume in 18 testing sites and the concentration of lead dust in 30 testing sites were 0.002-0.019 mg/m3 and 0.004-0.013 mg/m3, respectively. Pb-B level was positively correlated with Pb-U concentration (r=0.62, P<0.01) and ZPP level (r=0.47, P<0.01) and was negatively correlated with ALAD concentration (r=-0.77, P<0.01) in 233 workers with occupational lead exposure. Among 233 workers, 218 (93.6%) had ≤70 µg/L Pb-U, and 15 (6.9%) had ≥400≥g/L Pb-B. Pb-B level was not correlated with ZPP level as Pb-B level was <190 µg/L (r=0.18, P=0.068 ), while Pb-B level was positively correlated with ZPP level as Pb-B level was ≥190 µg/L (r=0.36, P<0.01). Pb-U concentration was positively correlated with ALA-U concentration (r=0.49, P<0.01) and ZPP level (r=0.47, P<0.01). ZPP level was negatively correlated with ALAD concentration (r=-0. 19, P<0.01), and was positively correlated with ALA-U concentration (r=0.27, P<0.01). ALAD concentration was not correlated with ALA-U concentration (r =-0. 11, P>0.05). And in 233 workers with occupational lead exposure, there were no significant differences in Pb-B level, ZPP level, and ALAD activity between the workers with ALAD1-2 genotype and the workers with ALAD1-1 genotype (P>0.05). In 76 workers with non-occupational lead exposure, there was no significant difference in Pb-B level between the workers with ALAD1-2 genotype and the workers with ALAD1-1 genotype (P >0.05). The workers with ALAD1-2 genotype had a significantly lower ALAD activity, and a significantly higher ZPP level compared with those ALAD1-1 genotype (P<0.01).
In the workers with low-level occupational lead exposure, ZPP level is positively correlated with Pb-B level when Pb-B level was ≥190 µ/L. ALAD could be used as an effect biomarker of low Pb-B level. ALAD gene polymorphism shows different effects on the Pb-B level and the toxic effects between the workers with occupational lead exposure and the workers with non-occupational lead exposure.
调查低水平职业性铅暴露工人的铅暴露情况、其影响以及易感性生物标志物之间的关系，并探讨其评估健康危害的敏感性和实用价值。
采用职业健康监测方法，对中国江苏省一家铅酸蓄电池企业工作场所的铅烟和铅尘浓度进行测定。采集233名职业性铅暴露工人和76名非职业性铅暴露人员的血样，用石墨炉原子吸收光谱法（GFAAS）测定血铅（Pb-B）水平，用血液荧光分析法测定锌原卟啉（ZPP）水平，用分光光度计测定δ-氨基乙酰丙酸脱水酶（ALAD）浓度，并用TaqMan实时聚合酶链反应测定ALAD基因多态性。同时，采集他们的尿样，用GFAAS测定尿铅（Pb-U）浓度，用分光光度计测定δ-氨基乙酰丙酸（ALA-U）浓度。采用多重线性回归方法分析上述指标之间的相关性。
18个检测点的铅烟浓度和30个检测点的铅尘浓度分别为0.002 - 0.019 mg/m³和0.004 - 0.013 mg/m³。在233名职业性铅暴露工人中，Pb-B水平与Pb-U浓度（r = 0.62，P < 0.01）和ZPP水平（r = 0.47，P < 0.01）呈正相关，与ALAD浓度（r = -0.77，P < 0.01）呈负相关。在233名工人中，218名（93.6%）尿铅≤70 μg/L，15名（6.9%）血铅≥400 μg/L。当血铅水平<190 μg/L时，Pb-B水平与ZPP水平无相关性（r = 0.18，P = 0.068），而当血铅水平≥190 μg/L时，Pb-B水平与ZPP水平呈正相关（r = 0.36，P < 0.01）。Pb-U浓度与ALA-U浓度（r = 0.49，P < 0.01）和ZPP水平（r = 0.47，P < 0.01）呈正相关。ZPP水平与ALAD浓度呈负相关（r = -0.19，P < 0.01），与ALA-U浓度呈正相关（r = 0.27，P < 0.01）。ALAD浓度与ALA-U浓度无相关性（r = -0.11，P > 0.05）。在233名职业性铅暴露工人中，ALAD1-2基因型工人与ALAD1-1基因型工人的Pb-B水平、ZPP水平和ALAD活性无显著差异（P > 0.05）。在76名非职业性铅暴露工人中，ALAD1-2基因型工人与ALAD1-1基因型工人的血铅水平无显著差异（P > 0.05）。与ALAD1-1基因型工人相比，ALAD1-2基因型工人的ALAD活性显著降低，ZPP水平显著升高（P < 0.01）。
在低水平职业性铅暴露工人中，当血铅水平≥190 μg/L时，ZPP水平与Pb-B水平呈正相关。ALAD可作为低血铅水平的效应生物标志物。ALAD基因多态性对职业性铅暴露工人和非职业性铅暴露工人的血铅水平和毒性效应有不同影响。
