|Local:||IPMA Algés Lisboa|
This presentation shows briefly several studies made to improve the knowledge about the sedimentary behavior of platinum group elements in hardly human-impacted environments. Most of them have been made in the salt marshes of the Tagus Estuary, being the IPMA (DivOA) deeply involved in. Besides, these studies have been part of the Clara Almécija´s PhD defense (from Instituto de Investigacións Mariñas IIM-CSIC, Vigo, Spain).
Platinum group elements (ruthenium, rhodium, palladium, osmium, iridium and platinum) are very scarce in the upper continental crust due to their siderophile character (affinity with iron), that makes them remain in the Earth´s core. However, the use of platinum group elements several human activities, especially in catalytic converters −which were developed to transform exhaust emissions into more harmless products− has increased their environmental concentrations close to urban and highly impacted areas, but also in remote ones like Antarctic snow.
Previous studies have concluded that there is an anthropogenic disturbance in the geochemical cycle of these elements, but which is their fate when arriving to natural environments is still poorly-known. Therefore, some questions like (i) the role of vegetation in the biogeochemical cycle of platinum group elements in sediments, (ii) their transference from sediment to biological compartments, (iii) their anthropogenic contribution in sediments and interstitial waters affected by different traffic impact, (iv) assessing their real coupled sources and behavior from anthropogenic origin or (v) evaluating the impact of PGE mining activities on the surrounding environments will try to be answered in this presentation.