Variations in the composition of house dust by particle size.

In this study, the distribution of heavy metals and other components in the various size fractions of house dust is investigated. A house dust sample collected from a vacuum cleaner was separated into size fractions by sieving and air classification. The analysis of the size fractions showed that the heavy metals and other components are not uniformly distributed in the various size fractions. The highest total carbon concentrations were found in the size fractions with a mass median diameter of 18-95 µm, while in the coarser size fractions and in the finest size fraction, the total carbon concentration was lower. In contrast, for many heavy metals and other metals (Al, Fe, Ca, S, Mn, Ti, Ba, Sr, As, Co, and V), the maximum concentrations were found in the finest size fraction. With increasing size of the dust fractions, the concentrations decreased. For several of these components, the dependence of the concentration on the particle size can be approximately assessed well using a power function. The distribution of Zn, Cu, Mg and Na was different. While the concentration of Na and Mg was higher in the coarser size fractions, no distinct trend was found for the concentrations of Cu and Zn.