Application of Graphite Furnace Atomic Absorption Spectrometry for the Determination of Lead Items in Dairy Products under Optimal Conditions
The latest edition of GB 2762-2022 Limit of Pollutants in Food of the National Standard for Food Safety strictly controls the limit index of lead items in dairy products.In order to adapt the limit value standard,the National Health Commission and the State Administration for Market Regulation revised and issued the GB5009.12-2023 Determination of Lead in Food of the National Standard for Food Safety method,which reduced the detection limit and quantitation limit of liquid food.The change of national standard has put forward higher requirements for the instrument conditions and parameters settings for the detection of lead items by graphite furnace atomic absorption spectrometry.In this study,the influence of different temperature and light spots at different positions of graphite tubes in each step of the temperature program on the labeling recovery results were compared and analyzed during the detection of lead items in liquid dairy products by graphite furnace atomic absorption spectrophotometer,and the optimalconditions of the temperature program were determined.At the same time,the adjusting methods and positions of the element light spots in the detection of samples with different lead contents were determined.