Magnetic, Geochemical, and Microstructural Characteristics of Road Dust on Roadsides with Different Traffic Volumes—Case Study from Finland

Abstract

The combination of magnetic, geochemical, and microstructural methods was used to characterize road dust properties in roadside soils of two sites in southern Finland: a highway (Tuusula no. 45, high traffic volume) and a local road (Mikkeli no. 13, low traffic volume). Significant differences in horizontal (κ) and vertical (χ) distribution of magnetic susceptibility were observed in the investigated roadside soils. These variations were concluded to be mostly associated to traffic volume, which is considered to be a major factor that determines the degree of particle emissions derived from vehicle traffic. Magnetic parameters of hysteresis, isothermal remanence magnetization (IRM) acquisition curves, and thermomagnetic data indicated coarsegrained (pseudo-single-domain/multi-domain) magnetite as the primary magnetic carrier. Scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy (EDX) analyses identified two groups of magnetic materials: angular/aggregate particles (diameter~2-100 μm) derived from circulation of motor vehicles (e.g., vehicle exhaust emission, cycling of dust in suspension due to vehicular movement, dispersion of road construction materials, and abrasion of tires, brake linings, and road surface), and magnetic spherules (d~3-15 μm) possibly originating from industrial and domestic heating systems. Concentrations of selected trace elements Cu, Zn, and Pb in highway roadside soils were significantly higher than those in local roadside soils.

Magnetic properties of agricultural soil in the Pearl River Delta, South China — Spatial distribution and influencing factor analysis

“…Besides natural factors, human activity may affect soil magnetism in many ways. Anthropogenic pollutants containing magnetic fractions, mainly derived from industry and transportation vehicles, can enhance soil magnetism in the surface layer (Blundell et al, 2009b;Bucko et al, 2010;Karimi et al, 2011;Meena et al, 2011). Cultivation may be another factor influencing soil magnetic characteristics.…”

Impact of noise barriers on the dispersal of solid pollutants from car emissions and their deposition in soil

“…As first observed by Hunt et al (1984) and later confirmed by Hoffman et al (1999) and Buaeko et al (2010), car emissions are also a source of technogenic magnetic particles (TMPs), which are the main carriers of heavy metals. TMPs are mainly magnetic Fe oxides and hydroxides, which presence in material can be easily detected via magnetic susceptibility measurements.…”

“…Research conducted so far has demonstrated that most car emissions are deposited in the close vicinity of roads (up to 10 m, with levels decreasing with increasing distance from the road edge (Hoffmann et al 1999, Buaeko et al 2010, Wawer et al 2015, Ojha et al, 2016.…”

Preliminary Results of the Environmental Magnetic Studies of the Slightly Urbanized Cities. Case Study From Truskavets (Ukraine) and Montpellier (France)

“…Результати вивчення доменного стану маг-нетиків зразків ґрунтів (Рис. 2) узгоджуються із даними наведеними у публікації [5]. Отже справді, крупнозерни-стий магнетит є основним магнітним мінералом забру-днених ґрунтів та знаходиться у межах псевдооднодо-менного-мультидоменного стану.…”

“…Отже справді, крупнозерни-стий магнетит є основним магнітним мінералом забру-днених ґрунтів та знаходиться у межах псевдооднодо-менного-мультидоменного стану. Крім того, спираючись на дані [5], у такому випадку ми можемо стверджувати, що концентрація міді, цинку та свинцю у забруднених ґрунтах та пилових фракціях є вищою у порівнянні із ґрунтами лісової території Трускавця.…”