X-ray solutions for trace elements in the environment @ Micro X-ray Lab

The study of trace elements in the environment requires sophisticated analytical techniques capable of probing the samples from the field scale to the microscopic scale. In addition, environmental samples can have very different aggregation states and compositions, and therefore highly versatile analytical procedures are desirable. X-ray based analytical techniques are suitable to address both these needs being very flexible for the analysis of all kind of samples (liquids, suspensions, solids, powders, living organisms, thin samples, etc.) at different length scales (from bulk to nanometer scale). Furthermore, X-ray analyses can provide different types of information (chemical, morphological, structural) which can be finally combined together for a more comprehensive view of specific environmental issues. Limited sample preparation and non destructivity are other two key characteristics which make X-ray analyses very effective for environmental applications. However, most often this type of instrumentation is dedicated to sectoral investigations and combining different techniques requires the involvement of a number of laboratories and analytical expertises. Within this context, a team of experts in different fields of X-ray analysis at the University of Bari has created a laboratory where different X-ray analytical techniques and expertises are available in a single place for several environmental applications. In particular, the following laboratory instrumentation is available: X-ray powder diffraction (XRPD), portable X-ray fluorescence (pXRF, for field studies), wavelength dispersive X-ray fluorescence (WDXRF), energy dispersive x-ray fluorescence (EDXRF), total reflection X-ray fluorescence (TXRF), micro X-ray fluorescence (μXRF), high resolution computed X-ray tomography (HRCT) and field emission scanning electron microscopy coupled with energy dispersive X-ray microanalysis (FESEM-EDX). Long experience with synchrotron X-ray analyses and connections with the main European synchrotron facilities also allows the team to perform advanced experiments with combined synchrotron X-ray techniques. All the information coming from both laboratory and synchrotron analyses, together with routine chemical-physical approaches, can be then combined to solve complex scientific problems related to trace elements in the environment. An overview of the techniques available at Micro X-ray Lab will be presented together with some applications in the field of soil, plant and Earth sciences.