【作者】 梁沂；

【导师】 秦锐；

【作者基本信息】 南京医科大学 ， 儿科学， 2001， 硕士

【摘要】 铅是一种有神经毒性的重金属元素，大量的研究已经表明：环境铅污染目前已成为一个重要的公共卫生问题。环境中的铅对儿童的体格和智能发育均构成危害。胎儿期是生长发育最为迅速的时期，环境铅污染能否通过孕母危害胎儿？在现有的研究中，已有报道孕期低水平的铅暴露对生后儿童的智力发育有影响，但关于感知觉方面影响的研究少有报道。研究目的 1．通过对低水平铅暴露孕妇的血铅水平、脐带血铅水平、母乳铅水平的的测定，了解母孕期血铅变化情况，母血铅与母乳铅水平的相关关系；同时检测血锌、钙的水平，了解血铅、锌、钙水平之间的关系。 2．通过对早期婴儿进行视觉诱发电位（Visual EvokedPotentials VEP），脑干听觉诱发电位（Brainstem Auditory EvokedPotentials BAEP）的检测，探讨孕期低水平铅暴露对婴儿的视、听觉发育的可能影响。研究方法 1．于孕妇妊娠中期及产时采静脉血检测血铅、锌、钙水平，婴儿断脐后取脐血，测血铅、锌、钙水平，收集初乳，检测乳铅、锌水平。 2．于婴儿生后3～5日内及婴儿3月龄时，进行VEP检测。于婴儿6月龄时行BAEP检测，同时作末稍血铅及血红蛋白水平检测。 南京医科大学硕士学位论丈 3．填写自编家庭社会情况调查表，查阅产科记录，记录孕妇和婴儿的各项有关情况。 4．资料的统计分析采用 Excel．0和 SPss 8·0 for WlfldOWS处理。研究结果 1．母孕中期血铅水平为N．289士0．05o）卜二 几，产时血铅：（0．242土 0．049）卜mol／L，脐血铅：（0．197土口．05）卜mol／L。孕中期血铅水平较高，至产前有所下降，产前血铅水平高于脐血铅水平，脐血铅水平相当于产前血铅水平的81％。 2．孕妇产时血铅水平与孕中期血铅水平相关（R—0．208，P二0．037），产时血铅水平与脐血铅水平相关（R二0．407，P＝0．00），产时血铅水平与母乳铅水平之间无相关。母孕期血铅及脐血铅水平与同期血锌、钙水平无明显相关。乳铅水平与乳锌水平呈负相关（R—0．263，P＝0．002）。 3．新生儿及 3月龄婴儿 VEP的 P；。。波的波幅和潜伏期与母孕期血铅及脐血铅水平无相关。 4．6月龄婴儿右耳BAEP的I、Ill、V波潜伏期与脐血铅水平呈正相 关，才 关系数分别 为：R＝0＊24，P＝0o13；R—0．592，P—0．020；R＝＝0．602，P—0．018。通过多元线性回归分析，脐血铅值均进入了关于右耳 BAEPI、Ill、V波潜伏期的方程。研究结论 1．孕期血铅水平呈动态变化，产时血铅水平低于孕中期血铅水平。 2．脐血铅水平与孕妇产时血铅水平呈正相关，约相当于产时血铅水平的sl％，表明胎盘对铅的屏障作用是不完全的，胎儿在母体内即可能受到铅的损害。 3．本研究中的孕期铅暴露水平对早期婴儿的视觉发育无明显影响。 2 南京医科大学硕士学位论文 4．脐血铅水平与早期婴儿右耳 BAEP的 I、Ill、V波潜伏期成正相关，多元回归分析发现，脐血铅水平对右耳BAEP的1、HI、V波潜伏期的贡献，在考虑了其它掺杂困素的影响后仍有统计学意义。提示孕期低水平铅暴露对早期婴儿的听觉发育有不利影响。更多还原

【Abstract】 Lead is a heavy metal with neurotoxicity, environmental lead pollution has been an important public hygienic problem. That lead can do harm to children’s somatic growth and intelligence has been proven in many studies. The studies of the influence of low-level lead exposure of women during pregnancy on children mostly focus on cognitive function, rarely on sensory function. Objective: 1. By the investigation of the level of blood lead (Pb-B) among pregnant women and their children, and milk lead level, the purpose to recognize the dynamic tendency of Pb-B level of pregnancy women, and the relationship between the levels of Pb-B and milk lead, we also investigated the levels of blood zinc and calcium to study the association between blood lead and zinc and calcium. 2. By the measure of visual evoked potentials(VEP) and brainstem auditory evoked potentials(BAEP) of early infants, the purpose to investigate the probable effects of lead exposure during pregnancy on visual and auditory functions in infants. Methods: 1. 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 determined with graphite stove atom absorption spectrophotometry. The concentration of blood zinc and calcium were also measured. The specimens of milk were also collected to determine the concentration of lead and zinc. 2. VEP was recorded in infants at 35 days of age and 3 months of age. BAEP was recorded in infants at 6 months of age, and the concentration of Pb-B and hemoglobin were determined at the same day. 3. Give out the questionnaire and refer to the case history to get the condition of women and infants. 4. All the data were dealt with Excel 7.0 and Spss 8.0 for Windows. Results: 1. The Pb-B levels were (0.289 0.050) j.imol/L at the second three months of gestation , (0.242 0.049) p.mol/L at delivery, (0.197 0.05 1) imol/L from umbilical cord. The Pb-B level at the second three months of gestation is higher than it at delivery, and the Pb-B level at delivery is higher than it in umbilical cord. The Pb-B level in umbilical cord is equal to 81% of that at delivery. 2. There were significant association between the levels of Pb-B of the second three months of gestation and delivery(R=0.208, P0.037), Pb-B levels of delivery and umbilical cord (R=0.407, P=0.00 1). Pb-B level was not significantly associated with milk lead level. Pb-B levels of pregnant women and umbilical cord were not significantly associated with the concentrations of blood zinc and calcium. There was a significant negative association between milk lead level and zinc level(R=-0.263, P=0.002). 3. There was no significant association between the Pb-B levels of pregnant women and umbilical cord and the indices of peak P100 of VEP in early infants. 4. There was a significant association between the Pb-B level of umbilical cord and the latencies of waves F.. III and V at right ear (R=0.624, P=0.013; R=0.592, P=0.020; R=0.602, P=0.018 respectively) . linear regression analysis revealed that contribution of Pb-B level of umbilical cord to the latencies of waves I. III and V at right ear was still statistically significant after adjusting other confounding factors. Conclusion: 1. There更多还原