Reference materials are an important tool in ensuring the validity of testing results. The use of standard materials in Vietnam is currently limited because the supply depends on foreign standard material manufacturers at a high cost, and there is no domestic manufacturer for water and food reference materials production. This study aims to provide a procedure reference materials production for heavy metals Pb, Cd, As, and Hg analysis in water. The reference materials were homogenized and stable for a period of 318 days from the date of manufacture. With the assigned values consistent with the concentration to be analyzed of the heavy metals in the normal water sample. The measurement uncertainty ranges from 7.0 to 21.7 %. These reference materials can be used for internal quality control for laboratories. The research provides a standard procedure for the following production times for reference materials for heavy metal analysis in water and also a premise for further research on standard samples with matrix and other analytical criteria.
Reference material, reference material production, water, heavy metal.
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