Differences in determination of Chemical elements in soil and attic dust samples due to various acid treatments, Slovenia

Abstract

The paper gives an assessment of relationship existing between analytical values of samples, which were treated with two different acid procedures: four acid digestion and extraction in aqua regia. The sample population consisted of 256 soil samples and 139 attic dust samples collected within the frame of various geochemical studies in Slovenia. After acid treatments, elementary composition of the samples was determined by means of ICP method. As we were interested in functional relationships between both treatment procedures, we performed bivariate analysis of elementary compositions. A regression line based on the logarithms of data was used as a basic correlation indicator. We correlated the following 31 elements: Al, Ag, As, Au, Ba, Bi, Ca, Cd, Co, Cr, Cu, Fe, K, La, Mg, Mn, Mo, Na, Ni, P, Pb, S, Sb, Sc, Sr, Th, Ti, U, V, W and Zn. The majority of analytical values for elements in our samples, treated with both procedures, showed a high degree of correlation and a good functional relationship. A weak relationship existed only between those elements that were on detection limits of the analytical method or had a weak variability (Ag, Ba, Bi, K, Na, Ti, and W). On the basis of the results of double treatment and analysis of samples we calculated the boundary, warning and critical values, which are related to four acid digestion.