LONDON, U.K.--Although "gray goo" made of self-replicating nanostuff is unlikely to doom the planet, some kinds of nanomaterials may indeed be hazardous and require a closer look, according to a 12-month study on nanotechnology published today by the U.K. Royal Society and the Royal Academy of Engineering. Overall, however, the report concludes that most nanotechnologies pose no new risk and no general moratorium is needed.
Many products of nanotechnology, such as computer chips and self-cleaning windows, are no cause for new concern, says mechanical engineer Ann Dowling, who led the study. But two types of nanomaterial--loosely defined as stuff smaller than 100 nanometers--are worth worrying about, the panel found, because some evidence suggests that loose nanoparticles and nanotubes can readily penetrate cells and are toxic.
For the environment, nanotechnology may be a double-edged sword. Nanoparticles hold promise in cleaning up contaminated soils and water. Yet some studies hint at possible danger to wildlife (ScienceNOW, 30 March). The U.K. study recommends prohibiting large-scale release of nanoparticles for remediation purposes "until it can be shown that the net benefits exceed the risks," says Dowling. Factories and laboratories producing nanoparticles and nanotubes should treat them as if they were hazardous and minimize their release into the environment.
The panel, which was commissioned by U.K. science minister David Sainsbury in July 2003, concluded that nanoparticles and nanotubes should be treated as new chemicals and their impacts on health and the environment be tested under existing U.K. and E.U. legislation. This goes further than the current philosophy in the United States, where, for instance, nanoscale particles of titanium dioxide (a chemical used in sunscreens and paints) are not considered different from larger-scale particles of titanium dioxide.
A crucial first step in deciding how to regulate nanomaterials and products of nanotechnology is to define how nanomaterials differ from their larger-scale counterparts, says physicist E. Clayton Teague, director of the U.S. government's National Nanotechnology Coordination Office. The American National Standards Institute in Washington, D.C., is currently working on this, he adds.