House dust metal determination by WDXRF technique

Abstract

In this work, an analytical procedure for the quantitative analysis of the metals determination in house dust samples by wavelength dispersive x-ray fluorescence technique (WDXRF) is described. The fundamental parameters method (FP) was applied and direct pressed powder technique was used for sample preparation. The methodology validation and measurement uncertainty were evaluated by the EURACHEM/CITAC Guide 4715-92, statistical tests. Na, Mg, Al, Si, P, S, Cl, K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Sr and Pb were determined in the standard reference materials.. The SRM data presented an uncertainty of measurement, calculated as the relative standard deviation (RSD), lower than 3% for all the elements at 0.05% significance level; except for Na, K, Ti, Ni, Se e Pb determination. These elements presented 10.9 - 3.4 – 5.4 – 5.7 – 5.0 -3.8 % RSD values, respectively. The accuracy of the method presented the Z-score values between -2<IzI2 for all elements, except to Cr, Cu, Zn, and Pb (2<IZI<3) showing the methodology application for metal determination in house dust samples. The detection and quantification limits were also determined for all the elements. The method compared to other instrumental techniques such as ICP/OES and AAS shows advantage, once the chemical treatments or complex dissolution processes are not required for samples preparation.