Abstract: A new method for the determination of trace arsenic and mercury in yam was established. The pretreatment methods for sample were studied，including microwave digestion and extraction. The instrument condition，acidity，KBH4 concentration and pre-reducer were optimized by hydride generation atomic fluorescence spectrometry. Results showed that the methods of microwave digestion and extraction have little difference. The linearity ranges for mercury and arsenic are 0—50 ng/mL and 0—100 ng/mL，respectively，and the detection limits of them are 0.005 ng/mL for mercury and 0.087 ng/mL for arsenic. The relative standard deviations are 2.13% and 3.92% for 4 ng/mL mercury and 20 ng/mL arsenic，respectively. The recoveries are 94.8%—102.9% and 91.5%—105.7% for mercury and arsenic，respectively.

摘要： 建立了一种测定山药中有害元素汞、砷的新方法。主要对样品的前处理过程进行了研究，比较了微波消解法和浸提法的实验结果。采用氢化物发生-原子荧光法测定，对仪器条件、酸度、KBH4浓度和预还原剂进行了优化。结果表明：微波消解法和浸提法的测定结果没有显著差异。利用本方法测汞、砷的线性范围分别为0～50 ng/mL、0～100 ng/mL，汞、砷的检出限分别为0.005 ng/mL、0.087 ng/mL，对4 ng/mL汞和20 ng/mL砷，相对标准偏差分别为2.13%和3.92%。汞回收率在94.8%～102.9%、砷回收率在91.5%～105.7%。