1. CNR-ISTEC-National Research Council of Italy, Institute of Science and Technology for Ceramics, Faenza, Italy
2. Doctoral school in Nanotechnology, University of Trieste, Trieste, Italy
3. Department of Chemical and Pharmaceutical Sciences, University of Trieste, Trieste, Italy
4. Department of Mathematics and Geosciences, University of Trieste, Trieste, Italy
5. Clinical Unit of Occupational Medicine, Department of Medical and Surgical Sciences, University of Trieste, Trieste, Italy
6. Center for Environmental Nanoscience and Risk (CENR), Department of Environmental Health Sciences, Arnold School of Public Health, University of South Carolina, Columbia, SC, USA