Warheit says his experiments so far have been relatively crude; he essentially squirts nanoparticles into the rats’ tracheas with a syringe. Now, Warheit is working on developing more realistic exposure methods for assessing risks and identifying a handful of nanoparticles that can serve as test models for nanomaterials in general. However, he says, don’t expect conclusive results for a few more years.
Regulatory agencies are also beginning to get involved. The U.S. Environmental Protection Agency is now in the midst of selecting about a dozen studies to fund under a $4 million solicitation for research proposals issued last July, says Barbara Karn, a coordinator of the funding program. The goal is to investigate health and environmental effects of nanomaterials, but the selection process is still in an early stage, and the research itself will take years, Karn says.
Meanwhile, a key question the agency faces is how existing protocols for regulating new chemical substances-such as those established under the Toxic Substances Control Act-apply to nanoparticles. The law governs certain chemicals but doesn’t distinguish among size scales; the issue is whether nanomaterials warrant the creation of a new category simply by dint of their size.
Kent Anapolle of the EPA’s Office of Pollution Prevention and Toxics says the EPA is relying on existing protocols, but is in the process of determining whether they are adequate. If new data and experience suggest they aren’t, he notes, then “we can craft a regulatory action any way we see fit to mitigate a risk.” The U.S. Food and Drug Administration is also relying on existing protocols for nanoscale zinc oxide and titania particles in consumer products ranging from sunscreens to cosmetics.
Europe is also in the early stages of grappling with the issue of nanoparticle safety. Last year, the European Union didn’t fund a proposed four-year program that would have created a pan-European collaboration of specialists assessing the workplace risks of airborne nanoparticles. That proposal could still be funded; meanwhile, some individual countries are pushing ahead. The U.K. has commissioned the Royal Society and the Royal Academy of Engineering to complete by this spring a preliminary study of the risks and benefits of nanoparticles and to specify the research that is needed to enable informed regulatory decisions.
The long-term hope is that nanotechnology will open vast commercial opportunities. But getting the hard data on the safety of many of the different nanomaterials in development will be a critical step.
|SOME EFFORTS AND PROPOSALS ON NANOPARTICLE SAFETY|
|U.S. Food and Drug Administration; |
U.S. Environmental Protection Agency
|Relying on existing protocols to regulate new nanomaterials, while developing data on toxicology, environmental fate, and tissue accumulation|
|U.K. Royal Society |
|Commissioned a blue-ribbon study to assess the risks and benefits of nanomaterials and make regulatory recommendations|
|Center for Biological and Environmental Nanotechnology, |
Rice University (Houston, TX)
|Director Vicki Colvin recommended that 5 percent of federal nanotechnology R&D expenditures be devoted to the study of environmental and societal consequences|
|ETC Group (Winnipeg, Manitoba)||Calling for moratoria on nanotechnology R&D until safety can be established; seeking an international convention to evaluate nanotechnology|
|Greenpeace Environmental Trust |
|Calling for far more research on nanotechnology’s environmental impact, but not endorsing moratoria|