Nanotechnology

Một bài nghe về công nghệ Nano. Tóm tắt: Manipulating materials at the atomic level can have astronomic repercussions, both positive and negative. The problem is, no one really knows exactly what these effects may be. To find out where we stand in the world of nanotechnology, host Steve Curwood talks with David Rejeski, director of the Project on Emerging Nanotechnology at the Woodrow Wilson Center.

CURWOOD: It's Living on Earth. I'm Steve Curwood.

Everybody, it seems, is interested in it. The military sees a chance to make things faster, smaller and more efficient. Medicine sees a way to treat any organ, including the brain and heart, without reaching for the scalpel or destroying healthy cells. Consumers can look forward to novel materials ranging from odor-free socks to glare-free glass.

The "it" is the emerging technology of the tiny. It's called "nanotechnology." "Nano" is the prefix the metric system uses for one billionth, so "nanotech" is about manipulating materials at one billionth of the size they are usually handled; in other words, down at the level of the single atom.

There are safety and ecological concerns about nano methods and materials, so the Environmental Protection Agency has just come out with a document to spark discussion of the arising technology's potential benefits and risks.

Joining me is David Rejeski. He directs the Project on Emerging Nanotechnology at the Woodrow Wilson Center in Washington, D.C. Hello, sir.

REJESKI: Hello. Glad to be here.

CURWOOD: I hear the term "nanotechnology" all the time, meaning small things in technology, but what exactly is nanotechnology for someone who's never heard of it?

REJESKI: I think it's useful to think of nanotech as a new way of making things rather than just a technology. We've reached a point based, really, on decades of research where we can actually see and manipulate individual atoms. And when we gain that level of control over matter, two really interesting things happen.

I think the first is that we can really fine-tune the behavior of a lot of substances we now use. And number two, it's going to allow us to discover whole new properties and new substances. We're not talking about science fiction. It's here now.

CURWOOD: How big is this nanotech thing?

REJESKI: You're going to see nanotechnologies in just about everything from consumer goods to medicines, food, energy production, aerospace. Right now, there's an estimated 1,600 firms globally involved in nanotech and, according to some estimates, there are probably 500 to 700 products already on the market.

CURWOOD: What products am I buying today that have it in it, and I don't even realize it?

REJESKI: Well, if you're a skier, it may be in the goggles and glasses that you have. One area where nanotechnology has found some applications is actually coating lenses, and you're able to actually fine-tune the properties of the lenses with very, very thin film. So you can make an anti-scratch, anti-glare, anti-fogging, anti-microbial; you can block out UV rays. You're going to see applications already in high-performance fabrics that are water and stain resistant.

One of the interesting things was in sunscreens. So they've been able to take some of the ultraviolet-blocking chemicals like zinc oxide – which are usually white and greasy so when you put them on you kind of look like a polar bear – and on a nano scale they can be made to be perfectly clear while retaining and, actually enhancing, a lot of the ultraviolet-blocking characteristics.

CURWOOD: Looking inside the Woodrow Wilson Institute's nanotechnology crystal ball, what do you see?

REJESKI: I find the medical applications actually the most exciting. They're exciting simply in terms of the huge impacts they could have on health across a wide range of diseases. Let me just give you one example: people in some of the universities now have taken gold, reduced to about the size of I think about 35 nanometers, and they coat it with an antibody that allows these particles to attach to cancer cells. Once you've attached the gold particle to the cancer cell it only takes a very small amount of energy, which you can deliver with infrared light that'll penetrate the skin, and you can heat that cancer cell up to about 50, 55 degrees centigrade and destroy it.

CURWOOD: Some say that nanotechnology is the next, well, maybe industrial revolution, because it has so many different applications in so many different fields. How could nanotechnology help play a part in helping the environment?

REJESKI: Well there's already some examples of nanotechnology that's being used to clean up groundwater pollution. And they actually take iron – simple iron, if you reduce it down to about 70 nanometers in size, it becomes very reactive. Essentially it's rusting, but it's rusting much faster. And it can actually be used to clean up groundwater pollution. So this is being injected into the ground and it's been shown to be, at least at about 20 sites now around the country, fairly effective in terms of dealing with a lot of chemicals that are in the groundwater.

CURWOOD: So, with great powers going to such small things, there must be some risks of having these things loose in the environment, right?

REJESKI: Well, yeah, I think that there's a number of potential risks. I mean, the research has provided some answers, but there's still a lot of knowledge gaps.

So, you know, if we look at the sunscreen issue, that's been researched now for actually three or four years. There's a big study that was done in Europe on what happens when you put these incredibly small particles on your skin. What they have found, for instance, is that it tends to be, I think, fairly good if you've got healthy skin. If you've got compromised skin, if you have cuts and bruises and that sort of thing, then it's less clear, obviously, what the impact might be.

There's not a lot of research on the impacts on the environment. Again, if you look at the sunscreen, what happens when that washes off into the marine habitats. Are there going to be impacts on marine mammals, fish, coral reefs, that sort of thing?

CURWOOD: It sounds like there's a fair lack of government involvement and supervision of the safety of nanotechnology. In your view, what should be done to ensure that consumers and the environment, whenever we and it is exposed to nanotechnology, that the stuff has been thoroughly tested and proven to be safe?

REJESKI: I think one of the things that can be done, obviously, is that companies could submit products to testing by third-party independent testers. I think groups like Underwriters Laboratory, Consumer Reports, those kind of independent third-party voices to consumers will play a very critical role, actually, as nanotech rolls out. Because there's just not a lot of public trust in either government or industry to manage these risks.

CURWOOD: David Rejeski is director of the Project on Emerging Nanotechnologies at the Woodrow Wilson International Center for Scholars in Washington, a partnership of the Pew Charitable Trust. Thank you so much.

REJESKI: Thank you.

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