Measurements of elemental composition in background aerosol on the west coast of Sweden

Abstract

Concentrations of 14 elements in long distance transported aerosol have been measured in a rural site on the W coast of Sweden. The measurements were made during one winter and two summer periods, 1981–1984. Sampling was made with a dichotomous virtual impactor. Element analysis was made by photon induced X-ray fluorescence. The element concentrations were related to air mass trajectories. A strong dependence of the concentration variations with air mass history is found for most elements, in particular Pb, S, V, Zn and Cl. Median concentrations for the 14 elements in the two size fractions are reported and compared with previous measurements in central Sweden at the same latitude. Significant deviations are found for S and V. Concentrations of particulate S have proven to be very insensitive to locally produced SO 2 emissions. This makes measurements of fine particulate S on the Swedish W coast an excellent tool for checking the S transport from other countries to Sweden. The ratios Br Pb in fine particles and the coarse/fine ratios for particulate lead have, together with air mass trajectories, been used to suggest source areas for automotive lead. The soil derived elements, Fe, Ca, Ti and Mn, also demonstrate variations with air mass trajectories. Enrichment factors for coarse particles of Ca, Mn and Ti with iron as a reference show variations that we believe are typical for the soil of the source area.