孕期妇女低水平铅暴露对婴儿听觉发育的影响

目的 探讨孕妇孕期低水平铅暴露对婴儿听觉发育的可能影响.方法 于孕妇妊娠中期及产时采静脉血检测血铅水平,婴儿断脐后取脐血测血铅,血铅水平作为孕期铅暴露状况的指标.至婴儿6月龄时行脑干听觉诱发电位(Brainstem Auditory Evoked Potentials BAEP)检测,作为铅暴露对婴儿听功能影响的研究指标.结果 (1)母孕中期血铅水平为0.289±0.050μmol/L,产时血铅0.242±0.049μmol/L,脐血铅:0.197～0.051μmol/L.(2)6月龄婴儿右耳BAEP的Ⅰ、Ⅲ、Ⅴ波潜伏期与脐血铅水平呈正相关.以脐血铅水平0.242μmol/L为界,将婴儿分为高、低铅暴露组,高铅暴露组婴儿右耳BAEPI、Ⅴ波潜伏期明显长于低铅暴露组.通过多元线性回归分析,脐血铅值均进入了关于右耳BAEPI、Ⅲ、Ⅴ波潜伏期的方程.结论 孕期低水平铅暴露对早期婴儿的听觉发育有不利影响.

Effects of Low-level Lead Exposure During Pregnancy on Auditory Development in Infants

Objective T o investigate the probable effects of lead exposure during pregnancy on auditory development in infants.Methods The specimens of blood were collected form women at the second three months of gestation and delivery and from umbilical cord,and Pb-B levels were determinded as a marker to reflect lead exposure.BAEP was recorded in infants at 6 months of age as effective indicators to study effects of lead on their auditory development.Results(1)The Pb-B levels were(0.289±0.050)μmol/L at the second three months of gestation,(0.242±0.049)μmol/L at delivery,(0.197±0.051)μmol/L from umbilical cord.(2)There was a significant association between the Pb-B level of umbilical cord and the latencies of waves Ⅰ、Ⅲ and Ⅴ at rightear.All the children were divided into two groups(high-blood-lead and low- blood-lead)according to the cut-off value for umbilical blood level of 0.242μmol/L,results indicated that latencies of wave Ⅰ and wave Ⅴ at rightear in children athigh-blood-lead group were obviously longer than those at low-blood-level group.Linear regression analysis revealed that contr ibut ion of Pb-B level of umbilical cord to the latencies of waves Ⅰ、Ⅲ and Ⅴ at rightear was still statistically significant after adjusting other confounding factors.Conclusion Low-level lead exposure during pregnancy can do harm to auditory development in infants.