铅烟尘暴露对工人血脂质过氧化及抗氧化酶的影响

Effects of Lead Fume and Dust Exposure on Lipid Peroxidation and Antioxidant Enzymes in Blood

目的探讨职业性铅暴露对工人血脂质过氧化及抗氧化酶的影响。方法选择广西某冶炼厂53名铅作业工人为暴露组，不接触铅烟尘及其他有害物质的志愿者66名为对照组，测定血铅（BPb）、血清丙二醛（MDA）含量及超氧化物歧化酶（SOD）、谷胱甘肽过氧化物酶（GSH—Px）活力。结果作业场所空气中铅烟平均浓度为0．43mg／m3（O．05～1．65mg／m3），铅尘平均浓度为0．44mg／m3（0．02～1．15mg／m3），均超过时间加权平均容许浓度。暴露组BPb含量高于对照组，400μg／L≤BPb〈600ptg／L组血清SOD活力高于BPb〈200μg／L组，BPb≥600μg／L组血清SOD活力低于其他各组，BPb≥600μg／L组血清GSH—Px活力低于400μg／L≤BPb〈600μg／L组，差异均有统计学意义（P〈0．05或P〈0．01）。结论400μg／L≤BPb〈600Mg／L时，可引起血清SOD活力增高；BPb≥600μg／L时则引起血清SOD、GSH—Px活力明显降低，提示，铅有自由基毒性。

Objective To study the effects of lead fume and dust exposure on lipid peroxidation and antioxidant enzymes in blood. Methods 53 lead exposed workers from a smeltery in Guangxi were taken as the exposure group; and 66 volunteers unexposed to lead and other hazardous materials were taken as the control group. The contents of blood lead（BPb）and MDA, the activities of SOD and GSH-Px in serum were measured. Results The average concentrations of Pb fume and dust in the air of workplaces were 0. 43 mg/ m3 （0.05~ 1.65 mg/m3 ） and 0.44 mg/m3 （0.02 ~ 1.15 mg/m3 ） respectively, all of which exceeded TWA concentration. The content of BPb in the exposed group was significantly higher than that of the control group. The activity of SOD in serum of 400 μg/L≤BPb〈600 μg/L subgroup was significantly higher than that of BPb〈200 μg/L subgroup, but the activities of SOD and GSH-Px in serum of BPb600 μg/L subgroup were significantly lower than those of other groups. The activity of GSH-Px in serum of BPb≥ 600 μg/L subgroup was significantly lower than that of 400 μg/L ≤ BPb 〈 600 μg/L subgroup. Conclusions When the concentration of BPb achieved 400~600 μg/L, it could increase the activity of SOD in serum. When the concentration of BPb was≥600 μg/L, the activities of SOD and GSH-Px in serum lowered obviously. It indicates that Pb becomes toxic to free radical.