INTERLABORATORY COMPARISON OF TRACE METAL ANALYSES BY GRAPHITE FURNACE (FLAMELESS ) ATOMIC ABSORPTION SPECTROSCOPY

摘要

The analytical sensitivity, precision, and accuracy of trace metal (Pb, Cd, Cr, Cu, Fe, and Mn) analyses on aqueous samples performed at ORNL using a flameless graphite furnace atomic absorption system was evaluated in comparison to analyses performed by three independent lab-oratories using similar systems. All laboratories analyzed replicates of the same five samples which included twice distilled water, two U.S. EPA reference trace metal standards and two natural water samples (rain and stream water). Although the laboratories were informed of the range of concentrations to be expected none were informed of the nature of the samples to be analyzed.nAnalyses performed at ORNL were generally superior with respect to sensitivity and precision to those performed elsewhere. Approximate limits of detection, as indicated by analyses of the distilled water performed at ORNL, were close to those claimed by the instrument manu¬facturer.