Risk assessment of engineered nanoparticles: the Particle Risk project

Speaker:

Giulio Pojana , Department of Environmental Sciences, University Ca’ Foscari of Venice

Co-Author(s):

Stefano Zuin1, Giulio Pojana2, Christian Micheletti1, Andrea Critto2, Antonio Marcomini2, Nicklas Raun Jacobsen3, Håkan Wallin3 and Lang Tran 4

1 Venice Research Consortium, VEGA Scientific & Technological Park, Venice, 30175, Italy. Email sz.cvr@vegapark.ve.it
2 Department of Environmental Sciences, University Ca’ Foscari of Venice, Venice, 30123, Italy.
3 National Research Centre for the Working Environment, Lersø Parkallé 105, DK-2100 Copenhagen Ø, Denmark.
4 Institute of Occupational Medicine, Research Park North Riccarton, Edinburgh, EH14 4AP, Scotland (UK).

Engineered nanoparticles are being increasingly used in various commercial products and for specific applications, resulting in a serious concern for the potential exposure to humans and the environment. Currently, very little is known about the potential risk to human health and environment of nanomaterials.
Within the EC funded PARTICLE RISK project, a bank of organic and inorganic nanosized particles (carbon black, fullerenes, carbon nanotubes, nanogold, quantum dots) was selected in order to assess the possible health risk from exposure to these particles through integration of consistent characterization activities, appropriate in vitro/in vivo toxicological experiments and exposure/risk assessment procedures.
The investigated nanomaterials have been thoroughly characterized before a complete toxicological experimentation in order to ascertain main toxicity-driving physico-chemical properties. Transmission Electron Microscopy (TEM) and Dynamic Light Scattering (DLS) were applied to measure particles size and size distribution, while Atomic Absorbance Spectroscopy (AAS) and Liquid Chromatography-Mass Spectrometry (HPLC-MS) based analytical methods were used for the quantitative uptake determination after in vivo experiments.
The selected nanomaterials were applied to in vivo intrathracheal instillation experiments in mice to investigate and compare possible toxic effects and inflammatory potential of these materials. A ranking of toxicity was eventually accomplished among selected particles: nanogold and C60 were very low or non-toxic at the tested concentration levels, whereas CdTe quantum dots resulted indeed very toxic. The obtained data permitted to obtain reliable response-dose data useful for providing effective hazard characterization, and to evaluate how nanoparticles-related properties (such as size, surface area, solubility, etc.) may affect their ability to interact with biological systems.
Finally, nanoparticles physico-chemical properties and toxicological investigation results, as well as available human exposure data (e.g., pathways, routes of exposure and human targets) and life cycle scenarios have been combined by means of a weight of evidence approach to assess the potential human risk due their exposure.
The Particle Risk project results emphasize the need to develop an integrated methodological approach for obtaining an adequate assessment and communication of potential health risks from exposure to these emerging materials.