Despite billions of dollars spent on nanotechnology research and development over the past decade, the human and environmental safety of nanomaterials remains unclear. As a result, a new nanomaterials safety research strategy is needed, and new governmental oversight is required to ensure the essential research is carried out, according to a report released today by the National Research Council (NRC).
Nanotechnology relies on the ability to engineer materials on the scale of billionths of a meter, the size of mere clumps of atoms. Engineered nanomaterials are already used in a wide variety of products, from cosmetics and food additives, to solar cells and drug delivery systems. In 2009, nanotechnology-based products raked in an impressive $225 billion. By 2015 that number is expected to rise to $3 trillion.
Nanotechnology's popularity has soared because at the nanoscale materials often exhibit unique electrical, chemical, and optical properties. For example, in bulk gold is typically inert. But on the nanoscale it can be used as a catalyst to promote numerous chemical reactions. But the unique properties of nanomaterials have also made it a challenge to gauge their safety. To make matters worse, even the same material can behave differently if it changes its size and shape at the nanoscale. And as researchers gain more experience with nanoengineering, they are creating more complex combinations of nanomaterials, which makes deciphering their safety even harder.
The nanotechnology community has grappled in recent years to come up with a strategy for systematically studying the safety of nanomaterials. In the United States, the National Nanotechnology Initiative (NNI) spends about $120 million a year on environmental, health, and safety (EHS) research. In 2008, NNI officials produced their first nanotechnology EHS research strategy, which they updated last year.
Despite this progress, the NRC report's authors found that gaps remain. Most notably, the report says, there has been little research in key areas, such as the effects on humans of ingesting nanoparticles, and the health and safety of complex nanomaterials made up of mixtures of different elements. "In spite of the need to provide more certain information on the potential EHS risks, the gaps in understanding identified in many scientific workshops over the last decade have not been aggressively addressed with needed research," the report states.
In hopes of improving matters, the report's authors sketched out a framework for a new nanotechnology EHS strategy. Instead of a shotgun approach that simply surveys a wide variety of nanomaterials in different environments, it calls for a systematic effort to evaluate the potential risks posed by different materials, the plausibility of exposure, and the likely severity of any such exposure. "This focuses the research on materials likely to cause harm," says Andrew Maynard, a risk scientist at the University of Michigan, Ann Arbor, and a member of the NRC committee that wrote the report.
In addition, the committee members recommended changing who oversees risk research. NNI currently consists of 25 different federal agencies that control their own spending on nanotechnology and EHS research. The National Nanotechnology Coordination Office helps those agencies coordinate their efforts to avoid duplication. But it has no authority to mandate who does what, including implementing the new research strategy recommended by the committee. "If there is nobody with authority to enact that, it's not going to go anywhere," Maynard says. So the committee suggested several options, including setting up a panel with budgetary authority within the White House's Office of Science and Technology Policy. But rather than recommend a complete solution, the committee decided to leave that decision to the Administration and Congress.