The data on ENM characteristics and their toxicological effects come from peer-reviewed literature, of which metadata is stored in the created RDF and in the collection spreadsheet. The collection spreadsheet, containing all data that was converted into RDF is available as Additional file 2. The RDF has been archived in Zenodo (). The annotations with MIEs and KEs were done with AOP-Wiki (). The federated SPARQL queries with the AOP-Wiki RDF utilized the