Metals in airborne particulate matter in rural Switzerland

Weekly samples of aerosol in nine size fractions were taken in the period October 1985 to September 1986, and were analyzed for Na, V, Mn, Cu, Zn, As, Cd and Pb.Sampling locations were south of Berne, Switzerland, at elevations of 515, 750, 940 and 1550 m above sea level.The results indicate that the particulate matter concentration decreases with increasing elevation, but the extent of this decrease depends on atmospheric conditions, and is more pronounced during fall and winter when frequent inversion situations occur.During a few weeks in February 1986 unusually high aerosol concentrations were observed with atypical As to Zn ratios. The meteorological situation indicated transport from Eastern Europe.Principal component analysis revealed two to three factors in every size fraction, which were considered to be an ‘anthropogenic’, a ‘soil’ and a ‘large particle’ sodium component.Single particle analysis of one summer and one winter sample (particle size 2–4 μm) provided a variety of particles previously described in the literature as well as nickel and silicon rich particles of unknown origin (summer sample).