Quantifying environmental and personal risks of nanotechnology for industry.

Regulators continue to pursue a comprehensive, generalisable, transparent, reliable, accurate and universally commended injury risk assessment methodology for nanomaterials. After a decade of intensive effort, it emerges that many of the prototype risk metrics are uninformative. This situation has given rise to practical, if non-validated, guidance in the form of control banding recommendations. While informative these are often logically deficient and take no account of risk context as captured in the concept of risk appetite. What emerges from an understanding of risk and from the usable data is the clear need for industry and insurers to agree a risk evaluation scheme based on threshold-for-concern and which motivates industry choices to achieve a below-threshold rating. The generalisable risk metrics for such an approach are listed in this paper.