Micro X-ray fluorescence as a potential technique to monitor in-situ air pollution

Metal traces from atmospheric deposition can be evaluated by standard biomonitors such as lichens. Lichens can be analyzed by several techniques in order to quantify metals. Micro X-Ray Fluorescence (mu XRF) is used for the lichen analysis. mu XRF technique has various advantages with respect of other methods: multi-elemental analysis, fast elemental determination and no contamination effect. Furthermore, mu XRF analysis can be performed in-situ, thus allowing to monitor efficiently industrial locations. An industrial district in the Brescia area was monitored by analysing lichens as bio-accumulator. To validate and quantify the mu XRF results, Atomic Absorption Spectroscopy (AAS) was employed. The morphology of the pollutants particles was investigated by scanning electron microscopy (SEM).