Nanotechnology has found its way into many products. Indeed, companies have claimed that more than 300 products are nanobased, according to a database maintained by the Woodrow Wilson International Center , in Washington, D.C. In some of these products, such as skin creams and toothpastes, nanoparticles are in contact with a person’s body, so many experts are concerned that the novel properties of nanoparticles could cause health problems.
The Wilson Center has been calling for more research into the potential toxicity of nanoparticles, and eventually for regulation of the new materials. In this week’s issue of the journal Nature , Andrew Maynard, the science advisor for the center’s nanotechnology project, along with 13 leading experts in nanotoxicity research, propose five challenges that they hope will help direct research.
Technology Review asked Maynard about the dangers of nanomaterials.
Technology Review : What evidence is there that nanotechnology requires special attention?
Andrew Maynard: Individual experiments have indicated that if you develop materials with a nanostructure, they do behave differently in the body and in the environment.
We know from animal studies that very, very fine particles, particles with high surface area, lead to a greater inflammatory response than the same amount of larger particles. We also know that they can enter the lining of the lungs and get through to the blood and enter other organs. There is some evidence that nanoparticles can move into the brain along the olfactory nerve, so this is completely circumventing the blood-brain barrier.
TR : If we already know nanomaterials can potentially be dangerous, why not regulate them now? Why not require companies to test their products to prove they are safe?
AM: They could do that, but then the question is, What are the appropriate tests? The last thing companies want to do is run conventional tests and bring a product to market, and then discover that they’ve missed something, or regulations change, and so they should have done something else.
TR : So we need more research. What is making getting definitive results so difficult?
AM: There really isn’t any consensus on how you go about evaluating the risks associated with carbon nanotubes yet. In cell cultures, you have to have some idea what kind of response you’re looking for. We already know in some studies that the lungs see carbon nanotubes almost as biological materials–they don’t see it as a foreign material. But then because of that, they start building up layers of collagen and cells around these nanotubes. They almost see them as a framework for building tissue on. Now, that actually may be a good thing in parts of the body, but in the lungs you end up using up the air space. But without that information, you wouldn’t necessarily know what were the appropriate cell tests to do in the first place.
TR : So given the need for more research, who’s going to fund it?
AM: Clearly there is joint responsibility between government and industry. There’s a fairly strong argument for governments around the world to invest in research on the basics: what makes these harmful, what makes them safe? But then industry clearly has a role to play, because if they’re commercializing these technologies, they have a responsibility to make sure that they’re safe. So industry has a role in taking the research that’s coming from governments, and then applying it to specific products and technologies.
TR : Once we know the dangers, who’s going to regulate nanotech? Do you think the existing federal regulatory agencies, like the EPA, can do it?
AM: I don’t know, and I’m not prepared to commit myself at this stage, because we are at such an early stage in the debate. The thing that concerns me is, there is very much a mind-set that is based on the conventional understanding of chemicals. But nanomaterials are not chemicals. They have a structural component there as well as a chemical component.
TR : You say we’re still at an early stage, but aren’t you also arguing for the need to get going, to do something now before something bad happens?
AM: That’s where you come down to talking about “oversight” rather than regulations. If you’re looking at developing best practices for handling nanomaterials, you can be far faster than you can with new legislation leading to regulation. So there are ways of dealing with challenges in the near future that don’t necessarily mean resorting to regulation.
TR : You’ve made the point that nanotech is moving too fast to keep up with, and you’ve proposed some interesting new technologies that could help.
AM: It’s very clear that we are moving into a new era in many ways. It’s very clear that conventional ways of doing things and thinking just aren’t going to be up to the job of dealing with some of these new technologies and products.
TR : You talked about developing smart sensors that measure not only the number of particles in the air that a worker might inhale, but also harmful effects.
AM: That’s right. You could imagine 10 to 20 years from now. You’re developing a new nanotechnology material. You have absolutely no idea whether it’s going to be safe or harmful. What if you had a little sensor that you could put on your body that began to flash if there was a possibility of having a hazardous exposure? That would mean not only measuring the amount of stuff you’re exposed to but actually that property of the stuff that is likely to lead to harm in the body, such as oxidative stress, which from what we can tell right now is a major indicator of potential hazard. It would be an indicator to say, “Hold on a minute, there may be a problem here.”
TR : You also say the Internet can help researchers coordinate their efforts. How?
AM: The beauty of the Web is you can use it in innovative ways to summarize information and to provide portals for information. There’s so much information out there at the moment that it’s virtually impossible to find anything of use unless you spend a lot of time and effort trying to do that. The only way that I can work effectively is if there’s a way of accessing synthesized and summarized information which is easily digestible and easily assimilatable.
TR : Have you considered a Wikipedia for nanotechnology research?
AM: The Wikipedia idea is something that has been talked about. And I think that either that or something like that is a very exciting idea. Of course you’ve always got the issue of validating the information which is there. But certainly I think that’s one of the innovative ways that we can look at this.
TR : Has anyone actually looked into establishing a sort of nanowiki?
AM: Not to my knowledge. But there are the beginnings of it. If you look at what Rice University has been doing, they have their publications database. The aim has always been to include in that a synthesis of the information to make it very accessible, and also to integrate that database with other information sources. So you’re beginning to see the basis of a reasonably holistic data portal there.
TR : Your article in Nature , though it provided some interesting challenges, still leaves out details about who should do what, and how it should be funded. Do you plan to release something with a bit more detail?
AM: The hope is that the decision makers will rise to the occasion and start doing this themselves. The hope is that this will happen quickly, but if it doesn’t, the question is, Can we flesh this out to help them put a framework in place? But I think the first step is to see how people respond to the challenge.
TR : Are there any signs that governments are going to do something?
AM: Yes, there are a couple of signs. At the last House science committee, the federal government in the U.S. was very strongly charged with taking the next steps, and taking them rapidly. If you look beyond the U.S. to some of the European countries, and to some extent Japan, you begin to see governments understanding the importance of taking strategic action. So I am hopeful. But of course the proof will be to see these strategies coming out and enacted.