Strategic approaches for the management of environmental risk uncertainties posed by nanomaterials

Central to the responsible development of nanotechnologies is an understanding of the risks they pose to the environment. As with any novel material or emerging technology, a scarcity of data introduces potentially high uncertainty in to the characterisation of risk. Early priorities are the identification of key areas of risk uncertainty and the strategic approach for managing and reducing these. This is important as the information subsequently gathered supports decision making and policy development. We identify one important source of uncertainty for the quantification of both hazard and exposure for nanomaterials, the complexity of their behaviour in natural systems. We then outline two approaches for managing this uncertainty, based on experiences with chemicals: one that primarily focuses on hazard and one that initially focuses on exposure. While each approach places emphasis on different information requirements a common feature is the considerable time lag between information gathering and subsequent decision making based on the evidence gathered. Complementary environmental surveillance approaches can act as a safety net, although it is not as yet clear how fit for purpose current monitoring programmes are in this regard.