Amato, F; Pandolfi, M; Viana, M; Querol, X; Alastuey, A; Moreno, T
Recent research interest has been focused on road dust resuspension as one of the major sources of atmospheric particulate matter in an urban environment. Given the dearth of studies on the variability of the PM sub(1) sub(0) fraction of road deposited sediments, our understanding of the main factors controlling this pollutant is incomplete. In the present study a new sampling methodology was devised and applied to collect PM sub(1) sub(0) deposited mass from 1m super(2) of road pavement. PM sub(1) sub(0) road dust fraction was sampled directly from active traffic lanes at 23 sampling sites during a campaign in Barcelona (Spain) in June 2007. The aim of the study was to gain more insight into the variability of mass and chemistry of road dust in different urban environments, such as the city centre, ring roads, and locations nearby demolition/construction sites. The city centre showed values of PM sub(1) sub(0) road dust within a range of 3-23mgm super(-) super(2), whereas levels reached 24-80mgm super(-) super(2) in locations affected by transport of uncovered heavy trucks. The largest dust loads were measured in the proximity of demolition/construction sites and the harbor entry with values up to 328mgm super(-) super(2). The city centre road dust profiles (%) were enriched in OC, EC, Fe, S, Cu, Zn, Mn, Cr, Sb, Sn, Mo, Zr, Hf, Ge, Ba, Pb, Bi, SO sub(4) super(2) super(-), NO sub(3) super(-), Cl super(-) and NH sub(4) super(+), but several crustal components such as Ca, Ti, Na, and Mg were also considerably concentrated. Locations affected by construction and demolition activities had high levels of crustal components such as Ca, Li, Sc, Sr, Rb and also As whereas ring roads, characterized by a higher load of uncovered heavy trucks showed an intermediate composition. Levels of PM sub(1) sub(0) components per area were also evaluated to quantify the resuspendable amount of each element from 1m super(2). In the inner city environment mean values of 1363 mu gCam super(-) super(2), 816 mu gOCm super(-) super(2), 239 mu gECm super(-) super(2), 13 mu gCum super(-) super(2), 12 mu gZnm super(-) super(2), 1.9 mu gSbm super(-) super(2) and 2.0 mu gPbm super(-) super(2), in PM sub(1) sub(0) in all cases, were registered. Moreover the deposited PM load at demolition/construction sites acts as a reservoir or trap for traffic-related particles, which gives rise to large amounts of hazardous pollutants, available for resuspension.
Article Subject Terms: Dust; Urban areas; Trucks; Lead; traffic; Reservoirs; Particulates; inner cities; Sediments; Harbors; Atmospheric pollution; Urban atmospheric pollution; Particulate matter; in urban air; Urban environment; Particulate matter in atmosphere; Article Geographic Terms: Spain, Cataluna, Barcelona; P 0000 AIR POLLUTION; M2 551.510.42 Air Pollution (551.510.42); EE 20; Air Pollution: Monitoring, Control & Remediation