Airborne concentration and deposition of trace metals and metalloids in an urban area downwind of a manganese alloy plant

Abstract

The evaluation of the content of metals and metalloids in particulate matter (PM) and in atmospheric deposition in areas impacted by local industries is essential from an environmental and health risk perspective. In this study, the PM10 levels and atmospheric deposition fluxes of potentially toxic metals and metalloids were quantified at three urban sites of the Cantabrian region (northern Spain), located at different distances downwind of a Mn alloy plant. The content of Mn, V, Fe, Ni, Cu, Zn, As, Mo, Cd, Sb and Pb in PM10 and in the water-soluble and insoluble fractions of the deposition was determined by ICP-MS. Among the studied elements, the highest concentrations in PM10 and deposition rates were found for Mn, Fe, Zn and Pb, associated with the Mn alloy industry, and for Cu, related to non-exhaust traffic emissions. The levels of Mn, Fe, Zn and Pb in PM10 were higher in autumn, when the most frequent winds blow from the S-SW, whereas their highest deposition rates were found in winter and autumn, which are characterized by high monthly average precipitations. The water-soluble fraction of the atmospheric deposition of most metals increased with distance from the Mn alloy plant. The highest water-soluble fractions were found for Ni (72%), Zn (62%), Cu (60%) and Mn (49%). These results will be useful for the health risk assessment of the metal exposure associated with Mn alloy plants, as well as for the evaluation of the metal burden to soil, water and ecosystems related to this industrial activity.