How to assess the risks of nanotechnology: learning from past experience.

Nanotechnology may yield a plethora of beneficial applications, but it can also be expected to present risks. The challenge is to anticipate and reduce environmental and health risks or, at a minimum, identify and deal with such threats once they begin to become evident. Past experience, particularly with the fuel additive MTBE (methyl tertiary butyl ether), provides valuable guidance on how to assess the potential risks of nanotechnology using a comprehensive environmental assessment approach, which combines a product life-cycle perspective with the risk assessment paradigm. This systematic approach can serve not only to guide the development of a research strategy for assessing the risks of nanotechnology but possibly even help avert unintended consequences of nanotechnology.