电感耦合等离子体质谱法同时测定居住区大气中痕量铅、镉

Determination of Trace Elements Cd and Pb in the Atmosphere of Residential Areas by Inductively Coupled Plasma-Mass Spectrometry

目的建立电感耦合等离子体质谱法测定居住区大气中有害痕量元素铅、镉的分析方法。方法通过超声浸提同时分离气溶胶样品中的铅、镉,对仪器工作参数进行优化,分别选取115In、204Tl作为测定元素的校正内标,有效克服了基体效应、接口效应和仪器漂移对测定信号产生的影响。在优化的仪器条件下,取采样滤膜分别加入低、中、高浓度标准溶液进行测定,计算加标回收率。结果测定元素标准曲线的相关系数均优于0.9997,气溶胶样品中镉和铅测定的方法检测限分别为0.007 ng/m3和0.045 ng/m3,通过测定标准参考物质GBW(E)080212考察方法的准确性,测定值均在标准值范围内。镉和铅两种元素的加标回收率在94.6%～107.1%之间,测定精密度在1.2%～3.7%之间。结论该方法精密度、准确性好,简便、快速、灵敏,适用于居住区大气中痕量元素镉、铅含量的测定。

Objectives The method of detecting trace elements cadmium （Cd） and lead （Pb） in the atmosphere of residential areas by Inductively Coupled Plasma-Mass Spectrometry was established. Methods The trace elements Cd and Pb from atmospheric particulates collected by the filter membrane were extracted by Ultrasonic leaching procedure.^115In and ^204T1 were selected as the internal standards in order to overcome the effect of matrix, interface and fluctuation of the instrument. The concentrations of cadmium and lead in aerosol samples were determined by Inductively Coupled Plasma-Mass Spectrometry under the optimized conditions of the instrument. The recoveries of standard addition were also tested. Results The linearity of working curves of four elements was satisfactory and the coefficients were over 0. 9997. The detection limit of the elements cadmium and lead was 0. 007 ng/m^3 and 0. 045 ng/m^3 respectively. The tested mean values were in agrement with the certified values of National Standard Reference Material GBW（E）080212 The recovery rate of the method was 94. 6% - 107. 1% , and the standard deviation was 1.2% -3.7%. Conclusions The established new method to detect Cd and Pb by Inductively Coupled Plasma-Mass Spectrometry was simple, rapid, sensitive and usful in the determination of trace elements Cd and Pb in the atmosphere of residential areas.