Validasi Metode Penetapan Kadar Logam Kadmium (Cd) dalam Sampel Tanah Menggunakan Spektrofotometer Serapan Atom (SSA)-Nyala

Soil has an important role in life on earth because it supports plant life by providing nutrients and water as well as supporting roots. One of the chemical elements that cause pollution is cadmium. The standard method for analyzing the content of cadmium metal in the soil is using a Flame Atomic Absorption Spectrophotometer (AAS) referring to SNI 8910:2021. This method changes the weight content from one gram to five grams of sample to obtain cadmium metal levels that can be detected by the instrument. Therefore, this method needs to be validated before being used for routine analysis in the laboratory. The validation parameters are linearity, precision, accuracy, method detection limit, and robustness. The Validation results were obtained for the linearity parameter correlation coefficient value of r = 0.999, %RSD repeatability precision parameter of 1.51%, and the intermediate precision was obtained by %RSD analyst 1 : 1.51% and analyst 2 : 0.82%, accuracy parameter obtained the %recovery results were (88.73-97.01)%, the LDM parameter was obtained at 2.03 mg/kg, the robustness parameter was obtained by F-count of 1.25 and F-table of 3.40 which shows the average assay of metals Cd weighing 1, 3, 5, and 8 grams that were not significantly different. Overall, the results of the validation show that the method of assaying cadmium metal using Flame-AAS complies with the acceptance requirements, therefore it can be used for routine analysis in the laboratory.