Variations in vanadium, nickel and lanthanoid element concentrations in urban air

Abstract

The emission of trace metal pollutants by industry and transport takes place on a scale large enough to alter atmospheric chemistry and results in measurable differences between the urban background of inhalable particulate matter (PM) in different towns. This is particularly well demonstrated by the technogenic release into the atmosphere of V, Ni, and lanthanoid elements. We compare PM concentrations of these metals in large datasets from five industrial towns in Spain variously influenced by emissions from refinery, power station, shipping, stainless steel, ceramic tiles and brick-making. Increased La/Ce values in urban background inhalable PM, due to La-contamination from refineries and their residual products (fuel oils and petcoke), contrast with Ce-rich emissions from the ceramic related industry, and clearly demonstrate the value of this ratio as a sensitive and reliable tracer for many point source emissions. Similarly, anomalously high V/Ni values (>4) can detect the influence of nearby high-V petcoke and fuel oil combustion, although the use of this ratio in urban background PM is limited by overlapping values in natural and anthropogenic materials. Geochemical characterisation of urban background PM is a valuable compliment to the physical monitoring of aerosols widely employed in urban areas, especially given the relevance of trace metal inhalation to urban health issues.

Global biogeochemical cycle of vanadium

“…92). Studies in Spain (101) and in the United States (14,102) show similar findings. Based on estimates of the current mix of petroleum products exploited (described above), we estimate that unconventional fuels, with their higher V concentrations, represent about 40.5% (166 × 10 9 g V/y) of the total V mobilized to the atmosphere from the extraction of petroleum (410 × 10 9 g V/y).…”

“…Our calculation of the sum of wet and dry deposition (72 × 10 9 g/y) is less than the estimated sources to the atmosphere, leaving us with an unbalanced budget for V in the atmosphere. In urban areas, airborne concentrations can exceed 10 × 10 −9 g/m 3 (14,92,101,102), so the atmospheric budget may be balanced by dry deposition near emission sources.…”

Variations in time and space of trace metal aerosol concentrations in urban areas and their surroundings

“…The average value for V/Ni in UCC is around 2, with most sedimentary rocks, the finer fractions of soils, and ambient atmospheric PM exhibiting values confined within a range of 1-4 (Rudnick and Gao, 2004;Pey et al, 2009). Similarly, V/Ni values in low-sulphur petcoke and fuel oils typically lie a range of 1-3, increasing to 4-8 in high sulphur residues such as petcoke and the cheaper bunker oils used as fuel by shipping on the open seas where harbour controls on sulphurous emissions do not apply (Moreno et al, 2010;Pandolfi et al, 2011a). In the case of the MSY and BCN averaged data, all three PM size fractions show a range in V/Ni of 1-3, making unlikely any significant influence from high-sulphur shipping emissions (although individual hourly V/Ni ratios could exceed this value, due to the influence of industrial local emissions or the sporadic arrival of air masses contaminated by the use of less clean oils).…”

Spatial distribution and potential sources of trace elements in PM10 monitored in urban and rural sites of Piedmont Region

“…In particular, V has, also in this case, the highest EF in SA. Vanadium is emitted from all sources using heavy fuel oils such as ship engines and power plants (Becagli et al, 2012;Moreno et al, 2010;Toscano et al, 2011): therefore, this result is probably due to the input of air from the sea, as SA is relatively close to an important harbour and to a great coal power station localised in Savona city (Liguria region). To evaluate this hypothesis we calculated back-trajectories Taking wind direction and atmospheric conditions data into account and running deposition simulations by NOAA Hysplit Dispersion Model (Draxler and Rolph, 2015) and found that, particularly during summer days, air masses arriving in SA originate mainly from sea.…”