Summary:
The determination of potentially toxic elements in soil and household dust is crucial for assessing risks to human health. This study examines urban and mining areas in Cyprus with the objectives of a) assessing the levels of potentially toxic elements (PTEs) in the soil around the abandoned copper mine in Kokkinopezoula in the Mitsero region, b) studying the composition of household dust in Mitsero, Nicosia, and Limassol for the first time, and c) investigating the bioaccessibility of PTEs through oral ingestion in Mitsero's soil and dust in the three study areas. Health risk assessment for children under 2 years old was also conducted based on the proposed methodology of the international project DUST SAFE. The data set of elemental contents was accompanied by magnetic susceptibility measurements, mineralogical analysis and pH measurements.
The median concentrations of elements after aqua regia dissolution in soil samples from Mitsero were found to be 4, 26, 85, 960, 20, 6, 75 mg/kg for As, Cr, Cu, Mn, Ni, Pb, Zn, respectively. Similarly, in dust samples, the median values after X-ray fluorescence analysis were 4, 120, 114, 302, 57, 21, 516 mg/kg for As, Cr, Cu, Mn, Ni, Pb, Zn. Statistical correlation of the studied parameters in dust revealed three distinct element groups: Pb-As, Zn-Cu, and Mn-Fe-Ni-Cr, suggesting different anthropogenic and geogenic sources. Soil grouping differs, possibly related to mining activities, the region's geology, and human activities. The highest bioaccessibility percentages of pseudo-total content in the soil, were determined for Zn (59%), Cr (35%), Ni (30%). In household dust, high bioaccessibility percentages were found for Zn (98%), Ni (52%), Cu (42%). Health risk assessment for children indicated that the studied household dust is within acceptable risk levels for all elements, while chromium for non- carcinogenic risk, had the highest value for all elements, possibly due to the geological substrate, but it did not exceed the limit.
The findings of this study are valuable for managing and reducing potential risks arising from indoor dust and soil exposure. Moreover, it positions Cyprus on the global map of household dust composition data, which is available online through the DUST SAFE project.
