Objective To evaluate the uncertainty for determination of lead content in cotton paper for Pu'er tea packaging by graphite furnace atomic absorption spectrometry. Methods Graphite furnace atomic absorption spectrometry was used to detect the lead content in cotton paper for Pu'er tea packaging and evaluate its uncertainty according to CNAS-GL 06:2018. Results The synthetic standard uncertainty was 0.0435 mg/kg. According to GB 4806.8-2016 National Food Safety Standard Paper and Paperboard Materials and Products for Food Contact, the residual amount of lead was not more than 3.0 mg/kg. The test result was expressed as (0.66±0.09) mg/kg, k=2, and the result was determined to be consistent. Conclusion The uncertainty mainly comes from the fitting of the standard curve, followed by the preparation of the lead standard intermediate solution and the repeatability measurement of the sample.
标题:石墨炉原子吸收光谱法测定普洱茶包装用棉纸中铅含量不确定度的评定
英文标题:Uncertainty evaluation for the determination of lead content in cotton paper for Pu’er tea packaging by graphite furnace atomic absorption spectrometry