Towards a safe nanotechnology: strategies for minimizing risks of potentially harmful nanoparticles

Abstract

In the last years, the massive production of nano-enabled products has raised concerns about potential hazardous effects of nanoforms on humans and, broadly, on the environment. On these grounds, a broad spectrum of stakeholders (manufacturers, researchers, regulators, policy makers) has advocated the adoption of the safety-by-design (SbD) approach for the production of nanomaterials and nano-enabled products. The characteristic of SbD is the assessment and minimization of risks in the design phase of a nano-enabled product, in sharp contrast with conventional risk assessment and management that evaluates and manages safety only after a product has been realized or even marketed. The hurdles in implementing the SbD scheme in nanotechnology come mostly from limited information available at an early stage of materials and product development. This work is framed within the safety by design (SbD) paradigm, which represents the foundational layer of the broader safe and sustainable by design (SSbD) framework proposed by the OECD. The analysis of existing knowledge, however, makes it possible to formulate, on the basis of the physical–chemical characteristics of the nanoparticles and nano-enabled products, hypotheses about the most probable sources of risks (hazards and/or release), which will inform, up front, about physical and chemical transformations that lead to safer materials and products. In addition to a catalogue of these physical chemical modifications, this paper proposes a decision process to identify the most appropriate transformations that minimize risks while preserving the technical function of the nanoforms. The connection of these physical–chemical transformations with outcomes of toxicological assays and release tests provides a powerful tool for checking the effectiveness of the SbD strategy adopted.