Validation of an X-ray methodology with environmental concern

The capabilities of test procedures toward the validation of X-ray fluorescence analysis with environmental concern were investigated. The applied analytical scheme was based on the combination of fusion and pelletizing technique for sample preparation, while matrix correction was performed by means of the fundamental parameter and the scattered radiation method. Validation was carried out in terms of precision, trueness, measurement uncertainty, limit of detection and test for homogeneity of the sample material. To confirm trueness for the examined calibration strategy, the bias of the recovery functions for each analyte under study was evaluated by means of orthogonal regression analysis. The investigations were focused on single laboratory validation. Consequently, the presented validation procedures were based nearly exclusively on certified reference material.