称取经研磨的样品0.500 0~1.000 0 g至25 mL石英烧杯中，加入1 mL硝酸浸泡1 h，在低温电炉上加热至完全炭化，移入500℃马弗炉中灰化4 h，冷却至室温后，加入4 mL硝酸（1+1）溶液，低温加热溶解残渣，冷却后用水定容至25 mL，用电感耦合等离子体质谱仪测定溶液中的铜、铅、锌、镉、铬。经灰化处理后的样品溶液中盐类和有机质大大减少，结合内标（¹⁰³Rh）校正可消除基体效应和物理效应。采用数学校正法消除¹¹⁴Sn对¹¹⁴Cd的干扰，通过干法消解样品除去有机质可消除⁴⁰Ar+¹²C对⁵²Cr的干扰。铜、铅、锌、镉、铬的质量浓度在一定范围内与其响应值呈线性关系，检出限（3σ）在0.005~0.44 μg·g^-1之间。加标回收率在80.0%~125%之间，测定值的相对标准偏差（n=11）小于10%。方法用于测定大米国家一级标准物质中铜、铅、锌、镉、铬的含量，测定值与认定值相符。

The grinded sample (0.500 0-1.000 0 g) was added to 25 mL quartz beaker, soaked with 1 mL of nitric acid for 1 h, heated on the low temperature electric furnace to complete carbonization, and transfered to muffle furnace for ashing at 500℃ for 4 h. After cooling to room temperature, 4 mL of nitric acid (1+1) solution was added to dissolve the residue by heating at a low temperature, and the solution was made up to 25 mL with water for determination of copper, lead, zinc, cadmium and chromium by an inductively coupled plasma mass spectrometer. The salt and organic matter in the sample solution after ashing was greatly reduced, and the internal standard (¹⁰³Rh) correction eliminated the matrix effect and physical effect. The mathematics correction method was used to eliminate the interference of ¹¹⁴Sn on ¹¹⁴Cd, and the organic matter was removed by dry digestion to eliminate the interference of ⁴⁰Ar+¹²C on ⁵²Cr. Linear relationships were found between values of the response and mass concentration of copper, lead, zinc, cadmium and chromium in definite ranges, and the detection limits (3σ) were in the range of 0.005-0.44 μg·g^-1. Values of recovery obtained by standard addition method were in the range of 80.0%-125%, and RSDs (n=11) was less than 10%. The proposed method was used to determine the contents of copper, lead, zinc, cadmium and chromium in the national standard reference materials of rice, giving the measured values consistent with the certified values.