ICP-MS测定铅同位素方法的建立及铅中毒儿童的溯源

Determination of lead isotope using ICP-MS and study on traceability of lead among lead-poisoning children

目的 优化高精密度电感耦合等离子体质谱(inductively coupled plasma mass spectrometer,ICP-MS)测定铅同位素比值(lead isotope ratio,LIR)方法,用于铅中毒儿童的铅暴露溯源。方法 通过数据采集参数的优化以及相关模式的选择,建立ICP-MS测定LIR方法。以4名住院铅中毒儿童为研究对象,采集研究对象的血样、尿样以及相关环境样品。应用已建立的LIR方法对铅中毒儿童的血样、尿样、环境样品进行分析,并利用二维溯源模型对铅中毒儿童进行铅暴露溯源。结果 在仪器优化后的条件下,^(204/206)Pb、^(207/206)Pb、^(208/206)Pb实际测定值与证书值接近,分别为(0.058 88±0.000 22)、(0.915 31±0.000 97)、(2.167 02±0.001 73);^(204/206)Pb、^(207/206)Pb、^(208/206)Pb测定值的精密度分别为0.37%、0.11%、0.08%。在铅中毒患儿铅溯源中,有两名患儿体内的LIR与涂抹于身上的红丹粉的LIR相近,有两名患儿与环境铅有关。结论 经优化的高精密度电感耦合等离子体质谱测定铅同位素比值方法,灵敏度高,可用于血、尿液和环境样品中铅的LIR测定,分析其来源。

Objective To optimize the method for determining lead isotope ratios(LIR)using a high-precision inductively coupled plasma mass spectrometer(ICP-MS),aimed at tracing the source of lead exposure in children with lead poisoning.Methods By optimizing data acquisition parameters and selecting relevant modes,an ICP-MS method for LIR determination was established.Four hospitalized children with lead poisoning were studied,and their blood samples,urine samples,and related environmental samples were collected.The established LIR method was applied to analyze the blood samples,urine samples,and environmental samples,and a two-dimensional source tracing model was used to trace the source of lead exposure.Results Under the optimized conditions of the instrument,the actual measured values of ^(204/206)Pb,^(207/206)Pb,and ^(208/206)Pb were close to the certified values,at(0.05888±0.00022),(0.91531±0.00097),and(2.16702±0.00173),respectively;the precision of the measured values for ^(204/206)Pb,^(207/206)Pb,and ^(208/206)Pb were 0.37%,0.11%,and 0.08%,respectively.In the lead source tracing of the poisoned children,the LIR in two children was similar to that of red lead powder used by themselves,and two children were related to environmental lead.Conclusions A more sensitive analytical method using an inductively coupled plasma mass spectrometer was established for the determination of LIR in blood,urine,and environmental samples and for analyzing the source of lead.