Validation and uncertainty estimation for multielement determination using ICP-OES according to the ASTM E2941-14 standard

Standardized analytical methods for determining elemental concentrations require thorough validation and estimation of measurement uncertainty.Inductively coupled plasma optical emission spectrometry (ICP-OES) is a widely used technique for multielement analysis with the ASTM E2941-14 standard specifying the analytical conditions for its application.This study aims to validate the ICP-OES method and estimate the expanded uncertainty for multielement determination in accordance with ASTM E2941-14.Method validation and uncertainty estimation were conducted following Eurachem (2014) and Eurachem-CITAC (2012) guidelines, respectively.The method demonstrated acceptable linearity, with coefficients of determination (R 2 ) ranging from 0.9972 to 1.0000 and correlation coefficients (R) from 0.9982 to 1.0000, exceeding the acceptance criterion (R 2 /R 0.995).Accuracy under repeatability conditions showed coefficients of variation between 1.0% and 8.0%, indicating good consistency.Trueness evaluation revealed no significant bias, with recovery rates within the acceptable range of 100% 10%.Combined uncertainty values ranged from 0.0425 (silver; Ag) to 0.5156 (scandium; Sc), corresponding to relative uncertainties of 1.25% to 8.16%, respectively.Expanded uncertainties ranged from 0.0850 (Ag) to 1.0312 (Sc).The dominant sources of relative uncertainty were associated with calibration curve-based concentration measurements and volumetric equipment.