Seasonal variations in the chemical composition of particulate matter: a case study in the Po Valley. Part II: concentration and solubility of micro- and trace-elements

Abstract

Size distribution (fine and coarse fraction) and solubility distribution (extracted and residual fraction) of 20 elements (As, Ba, Be, Cd, Co, Cu, Fe, Li, Mn, Pb, Ni, Rb, S, Sb, Se, Sn, Sr, Ti, Tl, V) in atmospheric particulate matter (PM) were determined during a 5-year field study carried out in the Po Valley (peri-urban area of Ferrara, in Northern Italy). By studying the contribution of the two size fractions and the two solubility fractions to the atmospheric concentration of each element, it was possible to obtain interesting information about the variability of PM sources, to assess the role played by atmospheric stability in determining pollution episodes, and to obtain an estimate of the bio-accessible fraction. Atmospheric stability is confirmed to be one of the main causes of atmospheric pollution in this area and is to be responsible for the pronounced winter increase in both PM and elemental concentration. Long-range transport of natural and polluted air masses caused temporary increases in PM and elemental concentration, while local industrial emission seemed to play a secondary role. Regulated elements were well below their concentration limit, but many toxic elements were in the form of fine particles and soluble chemical species, more accessible to the environment, and the human body.

Oxidative Potential of Selected PM Components

“…In general, according to the results of some previous environmental studies, the elemental solubility tends to be higher when the dust is generated by combustive processes, as PA and, at least in part, UD. [27,38] How the Figure 1 shows, the three methods give different results for each types of dusts. In agreement to previous studies [24] this result confirms that the chemical composition plays the most important role in the determination of the oxidative processes induced by PM.…”

Determination of water-soluble elements in PM2.5, PM10, and PM2.5-10 collected in the surroundings of power plants

“…The results show similar extraction percentages of the following elements in the fine (PM2.5) fraction: As, Cd, Mn, Pb, and Sb. They emphasize that the solubility for PM2.5 was higher than that for PM2.5-10 and that in some cases there were significant differences in the relative percentage concentrations for the extracted and the residue fractions [22,23].…”

“…At the same time, the authors state that among the various combustion processes, waste incineration didn't seem to be the main source of these soluble metals in PM2.5. During a five-year field study in the peri-urban area of Ferrara, in northern Italy, Canepari et al [22] studied the concentration and solubility of trace elements contained in fine (PM2.5) and coarse (PM2.5-10) fractions. The results show similar extraction percentages of the following elements in the fine (PM2.5) fraction: As, Cd, Mn, Pb, and Sb.…”

Improved Time-Resolved Measurements of Inorganic Ions in Particulate Matter by PILS-IC Integrated with a Sample Pre-Concentration System

“…Natural radioactivity has been proved to be a reliable good proxy of the mixing properties of the lower boundary layer and a valuable tool for the interpretation of pollution events (Perrino, Pietrodangelo et al 2001;Vecchi et al 2004;Perrino et al 2009;Canepari et al 2014).…”