title: Identification of magnetic particulates in road dust accumulated on roadside snow using magnetic, geochemical and micro-morphological analyses.
abstract: The aim of this study is to test the applicability of snow surveying in the collection and detailed characterization of vehicle-derived magnetic particles. Road dust extracted from snow, collected near a busy urban highway and a low traffic road in a rural environment (southern Finland), was studied using magnetic, geochemical and micro-morphological analyses. Significant differences in horizontal distribution of mass specific magnetic susceptibility (χ) were noticed for both roads. Multi-domain (MD) magnetite was identified as the primary magnetic mineral. Scanning electron microscope (SEM) analyses of road dust from both roads revealed: (1) angular-shaped particles (diameter∼-300 μm) mostly composed of Fe, Cr and Ni, derived from circulation of motor vehicles and (2) iron-rich spherules (d∼2-70 μm). Tungsten-rich particles (d<2 μm), derived from tyre stud abrasion were also identified. Additionally, a decreasing trend in χ and selected trace elements was observed with increasing distance from the road edge.
authors.affiliation: Division of Geophysics and Astronomy, Department of Physics, P.O. Box 64, Gustaf Hällströmin katu 2, 00014 University of Helsinki, Finland. michal.bucko@helsinki.fi
authors.forename: Michał S
authors.initials: MS
authors.lastname: Bućko
authors.forename: Tadeusz
authors.initials: T
authors.lastname: Magiera
authors.forename: Bo
authors.initials: B
authors.lastname: Johanson
authors.forename: Eduard
authors.initials: E
authors.lastname: Petrovský
authors.forename: Lauri J
authors.initials: LJ
authors.lastname: Pesonen
mesh_terms: D004391:Dust / Q000032:analysis*; D004784:Environmental Monitoring / Q000379:methods*; D005387:Finland; D008280:Magnetics; D008855:Microscopy, Electron, Scanning; D012914:Snow / Q000737:chemistry*; D001335:Vehicle Emissions / Q000032:analysis*
chemical_list: D004391:Dust; D001335:Vehicle Emissions