酵母抽提物样品（1.000 g）经硝酸（20 mL）消解并蒸干后加水（10 mL），调整其酸度至pH 4.0。溶液通过D401离子交换树脂分离，用0.002 5 mol·L^-1硝酸溶液（pH 2.6）淋洗交换柱后，用0.2 mol·L^-1硝酸溶液洗脱吸附于树脂上的铅（Ⅱ）和镉（Ⅱ）。将洗脱液蒸至近干，用水定容至10 mL。用石墨炉原子吸收光谱法测定其中铅、镉的含量，两者的线性范围依次为50~350，3~15 pg，检出限（3s）依次为5.0，0.3 pg。对3个实样按所提出方法进行分析，并用标准加入法计算方法的回收率为84.0%~115%，测定值的相对标准偏差（n=8）为1.8%~12%。

The sample (1.000 g) of yeast extract was digested with HNO₃ (20 mL). The solution was evaporated to dryness, and the residue was taken up with water (10 mL), and the acidity was adjusted to pH 4.0. D401 ion-exchange resin was used for separation of lead and cadmium from the solution. After rinsing the column with 0.002 5 mol·L^-1 HNO₃ solution (pH 2.6), lead(Ⅱ) and cadmium(Ⅱ) were desorbed from the column with 0.2 mol·L^-1 HNO₃ solution, and the eluate was evaporated to near dryness. Water was added attaining to 10 mL, and contents of lead and cadmium in the solution were determined by GFAAS. Linearity ranges were found between 50 to 350 pg (lead) and 3 to 15 pg (cadmium), with detection limits (3s) of 5.0, 0.3 pg respectively. Three samples were analyzed by this method, and values of recovery found by standard addition method were in the range of 84.0% to 115%, giving values of RSD's (n=8) ranged from 1.8% to 12%.