Study on reference material of heavy metals (lead, cadmium, arsenicic, and mercury) in mustard greens by natural infection method

Vegetables are an essential part of daily meals. Each type contains different nutrients and serves various functions, but all provide essential nutrients for human health. Many metal elements are known to play important roles in living organisms and humans. However, heavy metal contamination can be toxic to the body and impact the health of consumers. To ensure the quality of vegetable products, determining the levels of heavy metals (Pb, Cd, As, Hg) is crucial for food safety control in vegetables. Therefore, using heavy metal standard samples (Pb, Cd, As, and Hg) in vegetables provides reference values and accuracy benchmarks for testing results, aiding in precise and objective evaluation during sample testing. This study aims to develop a process for creating standard samples for analyzing heavy metals Pb, Cd, As, and Hg in vegetables using a natural contamination method. The produced samples demonstrated consistency and stability, with an estimated duration of 627 days from the production date. The measurement uncertainty ranges from 7,94% to 15,7%. The values of the standard samples align with the low contamination levels required for analysis, making them suitable for quality control in laboratories. Additionally, the results of this study lay the groundwork for further research into developing other standard samples with diverse matrices and analytical criteria using natural contamination methods.