Dimensional characterization of selected elements in airborne PM10 samples using μ- SRXRF.

Micro synchrotron radiation X-ray fluorescence (m-SRXRF) is a powerful spectroscopy technique that uses synchrotron radiation to induce X-ray fluorescence in samples and provides exhaustive information on the micron and submicron scale. Among the major advantages of m-SRXRF spectroscopy are its nondestructive nature and that samples can usually be analyzed without pretreatment. At the ESRF (Grenoble, France) ID-21 beamline, we examined PM10 samples collected at two sites in the Province of Trieste, Italy, in order to determine possible correlations among some low- to mid-Z elements (S, Cl, K, Ca, Ti, V, Cr, Mn, and Fe), as well as investigated the possibility of using synchrotron radiation imaging techniques as a way to examine the granulometry of PM10 particles containing the various chemical elements. A consistent significant correlation between Ca and S has been found, which, coupled with the data obtained in a related study, indicates that a major part of the sulfate is present as CaSO4. Granulometry measurement via imaging techniques has shown that some elements such as Fe, Ca, and S are more amenable to this type of analysis than others. Additionally, the spatial homogeneity of a PM2.5 certified reference material (NIST SRM-2783) has been investigated by analyzing four adjacent areas on the certified sample (total area 1mm 2 ). The certified reference material has shown a percentage relative standard deviation less than 7% for Al, Si, P, S, Cl, K, Ca, V, Cr, and Fe, and close to 17% for Ti and Mn. Copyright © 2011 John Wiley & Sons, Ltd.