Evaluation of the contamination of platinum in estuarine and coastal sediments (Tagus Estuary and Prodelta, Portugal)

► Traffic-borne contamination leads to elevated Pt concentrations in coastal sediments. ► Up to 25-fold Pt enrichment was found in surface sediments of the Tagus Estuary. ► Down-core rapid decrease of Pt reveals the absence of significant previous inputs. ► Post-depositional mobility may disturb the anthropogenic Pt signature in sediments.