Emerging nanomaterial governance systems: the state of play.

Domestic laws, their implementing regulations and policies, and government and private-party governance programs are now being carefully reviewed and revised to enhance their utility to manage the potential risks posed by nanoscale materials. Whether existing laws and their implementing programs are adequate to address such risks will continue to inspire debate and legislative and regulatory initiatives for years to come. This article reviews existing legal and governance oversight systems and analyzes their strengths and deficiencies in addressing the potential risks posed by nanoscale materials and in fostering nanotechnology's promise. Particular attention is devoted to emerging regulatory approaches the US Environmental Protection Agency is taking under the Toxic Substances Control Act and the Federal Insecticide, Fungicide, and Rodenticide Act, the two domestic chemical product laws primarily responsible for ensuring the safety of chemical substances and mixtures.

Nanomaterial categorization for assessing risk potential to facilitate regulatory decision-making.

For nanotechnology to meet its potential as a game-changing and sustainable technology, it is important to ensure that the engineered nanomaterials and nanoenabled products that gain entry to the marketplace are safe and effective. Tools and methods are needed for regulatory purposes to allow rapid material categorization according to human health and environmental risk potential, so that materials of high concern can be targeted for additional scrutiny, while material categories that pose the least risk can receive expedited review. Using carbon nanotubes as an example, we discuss how data from alternative testing strategies can be used to facilitate engineered nanomaterial categorization according to risk potential and how such an approach could facilitate regulatory decision-making in the future.

A multi-stakeholder perspective on the use of alternative test strategies for nanomaterial safety assessment.

There has been a conceptual shift in toxicological studies from describing what happens to explaining how the adverse outcome occurs, thereby enabling a deeper and improved understanding of how biomolecular and mechanistic profiling can inform hazard identification and improve risk assessment. Compared to traditional toxicology methods, which have a heavy reliance on animals, new approaches to generate toxicological data are becoming available for the safety assessment of chemicals, including high-throughput and high-content screening (HTS, HCS). With the emergence of nanotechnology, the exponential increase in the total number of engineered nanomaterials (ENMs) in research, development, and commercialization requires a robust scientific approach to screen ENM safety in humans and the environment rapidly and efficiently. Spurred by the developments in chemical testing, a promising new toxicological paradigm for ENMs is to use alternative test strategies (ATS), which reduce reliance on animal testing through the use of in vitro and in silico methods such as HTS, HCS, and computational modeling. Furthermore, this allows for the comparative analysis of large numbers of ENMs simultaneously and for hazard assessment at various stages of the product development process and overall life cycle. Using carbon nanotubes as a case study, a workshop bringing together national and international leaders from government, industry, and academia was convened at the University of California, Los Angeles, to discuss the utility of ATS for decision-making analyses of ENMs. After lively discussions, a short list of generally shared viewpoints on this topic was generated, including a general view that ATS approaches for ENMs can significantly benefit chemical safety analysis.