Baranowska I
Department of Analytical and General Chemistry, Silesian Technical University, Gliwice, Poland.
Occup Environ Med. 1995 Apr;52(4):229-32. doi: 10.1136/oem.52.4.229.
To measure the concentrations of the trace elements lead and cadmium in human placenta and in maternal and neonatal (cord) blood. To assess the influence of the strongly polluted environment on the content of metals in tissues and on the permeability of placenta to cadmium and lead. Various methods of mineralisation were tested before analysis.
Graphite furnace atomic absorption spectrometry was used for the determination of lead and cadmium. The samples for analysis were prepared by mineralisation under pressure in a Teflon bomb (HNO3, 110 degrees C), by wet ashing under normal pressure (HNO3 + H2O2 for 12 hours), and by microwave digestion in concentrated nitric acid.
In analysed samples the following mean concentrations of cadmium and lead were found: in venous blood Pb = 72.50 ng/ml, Cd = 4.90 ng/ml; in placenta Pb = 0.50 microgram/g, Cd = 0.11 microgram/g; in cord blood Pb = 38.31 ng/ml, Cd = 1.13 ng/ml.
High concentrations of lead and cadmium were found in placentas and in maternal blood whereas in neonatal blood there was an increased concentration of lead and only traces of cadmium. It is concluded that the placenta is a better barrier for cadmium than for lead. Among the examined methods of mineralisation, microwave digestion was the best.
测量人胎盘以及母血和新生儿（脐带）血中微量元素铅和镉的浓度。评估重度污染环境对组织中金属含量以及胎盘对镉和铅通透性的影响。分析前测试了各种矿化方法。
采用石墨炉原子吸收光谱法测定铅和镉。分析样品通过在聚四氟乙烯消解罐中加压矿化（硝酸，110摄氏度）、常压下湿式灰化（硝酸+过氧化氢，12小时）以及在浓硝酸中微波消解来制备。
在所分析的样品中，发现镉和铅的平均浓度如下：静脉血中铅=72.50纳克/毫升，镉=4.90纳克/毫升；胎盘中铅=0.50微克/克，镉=0.11微克/克；脐带血中铅=38.31纳克/毫升，镉=1.13纳克/毫升。
在胎盘中以及母血中发现铅和镉的浓度较高，而在新生儿血液中铅浓度升高且仅含有痕量镉。得出的结论是，胎盘对镉的屏障作用比对铅的更好。在所检查的矿化方法中，微波消解是最佳方法。
