Elemental content of aerosol particles in an underground tram station

Abstract

Particulate matter is an important air pollutant, especially in closed environments like a tunnel. The aim of this study was to determine the mass, black carbon, and elemental concentrations of particulate matter of two size fractions at an underground tram station in Hammarkullen, Gothenburg, Sweden. Samples were collected during June 2007 using a dichotomous virtual impactor separating the sampled aerosol particles into coarse (PM (2.5 -10) ) and fine (PM 2.5 ) fractions. To minimize the possible influence of waiting passengers, the platform for trams going towards the suburb Angered was chosen. The elemental analysis of the samples, collected on Teflon filters, was carried out using energy dispersive x-ray fluorescence (EDXRF) spectrometry, resulting in concentrations of 14 elements in most of the samples. Principal component analysis (PCA) was applied to identify possible sources for the elements in the particles. Owing to the tunnel environment, the elemental difference between the fine and coarse particle fractions was not as large as that in similar particles collected under normal outdoor ambient conditions. Likewise, the influence of the local weather situation was not significant. Particle content from the tram traffic was identified by PCA, with Fe being the major element in both coarse and fine particles. The particle mass concentration was higher in the tunnel compared to the ambient concentration at the monitoring station Femman in downtown Gothenburg. In some days, the mass concentration exceeded the Swedish daily ambient air quality standard of 50 µg m −3 , but it was lower than the limits in the environmental work act, 5 mg m −3 .

Atomic spectrometry update–X-ray fluorescence spectrometry

“…The analytical need was ably fulfilled with m-SRXRF. Boman et al 289 were interested in closed environments, such as a tunnel, where particulate matter is an important air pollutant. They determined mass, black carbon and elemental concentrations of particulates in two size fractions at an underground tram station in Gothenburg, Sweden.…”

A study to discriminate local, urban and regional source contributions to the particulate matter concentrations in the city of Dresden, Germany

“…A further important source for Fe and Ti is coal burning (e.g. Jayasekher 2009; Thurston et al 2011) and for Fe, especially in narrow urban streets, abrasion from tram line rails and brake pads (Thorpe and Harrison 2008;Boman et al 2009). The Fe concentration in PM 10 of about 1 μg m −3 averaged over the period from 09/2006 to 08/2007 was found to be two-to threefold higher at DN (kerbside, re-suspended road dust, road works nearby) than at DHG (urban background).…”