NOT long ago Ella Standage was woken by a bad dream about nanobots. She was terrified that nanoscale machines might replicate uncontrollably and turn the entire planet into grey goo. Ms Standage is not the only one to worry about such imaginary horrors, but at least she has an excuse: she is only four years old.
The grey-goo idea goes back to a prediction by Eric Drexler, chairman of the Foresight Institute, a nanotechnology-policy group in Palo Alto, that one day all manufacturing would be done by very tiny robots. He thought that given the correct plans, these minute devices would be able to produce any item—an engine, say, or a pair of jeans—from nothing more than a feedstock of atoms.
For this plan to work, though, these robots would have to be able to make more of their own kind, otherwise things would take far too long to build. Mr Drexler thought these hypothetical nanobots would have to be self-replicating, and gave warning that care would have to be taken to ensure they did not replicate out of control. This idea launched a wave of public concern. If these nanobots started making copies of themselves by scavenging materials from their environment, it was suggested, they would eventually become visible to humans as a seething mass of tiny robots, or grey goo—and might ultimately consume the entire planet.
Little wonder that nanobots have become a favourite new bogey in everything from children's cartoons (where Ms Standage learned of them) to films. In vain do scientists protest that as yet nobody knows how to build a self-replicating robot of any size. They have also put forward various theoretical reasons why there could never be such a thing. For example, they ask, how would those robots get the energy to survive? But lack of feasibility is no obstacle to the imagination, and the idea of nanobots fits well with contemporary fears about out-of-control science.
However, interest in grey goo seems to be on the wane as more serious concerns about the potential toxicity of nanoparticles are emerging. It is already clear that some manufactured nanoparticles are harmful to mice and fish. Ken Donaldson, a professor of respiratory toxicology at the University of Edinburgh, says that nanoparticles and nanotubes are likely to be far more toxic than the same chemical in larger form because smaller particles have a greater surface area and are far more reactive. Being so tiny, these particles may be able to penetrate cells and evade the human immune system. When inhaled, says Mr Donaldson, fine carbon particles are able to enter the blood and the brain. Last year Swiss Re, an insurance company, published an alarming report on the possible dangers of nanoparticles and the liability issues that could arise from products using them.
However, a report last year from Britain's Royal Society said that in most cases people's exposure would be limited: where nanoparticles had been used as raw materials, ingredients or additives in a product, they would usually be contained within a composite or fixed to a surface. Indeed, nanoscale materials have been used for years, for example in computer hard drives, without causing any problems. If governments, industry and scientists continue to take the issue seriously, creating new nanoparticles seems no more risky than creating new chemicals.
Besides, nanoparticles are already all around us: the air is full of them, from the exhaust of diesel engines, cigarette smoke, hairspray, burning candles and toast. People create and use all sorts of nasty toxic chemicals every day. Moreover, many willingly have their faces injected with botox, a highly toxic substance, purely to indulge their vanity.
In fact, toxic nanoparticles will have their uses. Scientists are already trying to wrap them in harmless coatings so they can be used to fight diseases or destroy cancerous cells. The tailored delivery of a toxic nanomaterial to treat cancer would be far preferable to existing methods that flood a patient's entire body with toxins. The ability of nanoparticles to cross the blood-brain barrier may also turn out to be useful because at present it is very difficult to get drugs across that barrier. Yet more information about the toxicology of these materials is urgently needed, and a great deal of work is already under way.
Even so, one small but vocal anti-nanotechnology group, the Action Group on Erosion, Technology and Concentration (ETC), has called for a complete moratorium on the use of synthetic nanoparticles such as quantum dots, nanowires and nanotubes. ETC, based in Canada, is a small fringe group of activists, but hogged the headlines when its concerns were picked up by Britain's Prince Charles.
Most advocates of nanotechnology say that a ban would stop research to assess and mitigate any risks. In June last year, a group of nanotechnology experts from 25 countries met in Virginia under the auspices of America's National Science Foundation to discuss how nanotechnology could be developed responsibly. Most of them agreed that no moratorium should be imposed because it would prevent any risks from being assessed.
Even Jim Thomas, ETC's programme manager, who is based in Oxford, thinks this aspect of nanotechnology is “a manageable issue”, and hopes that the debate will not be about health alone. What really troubles ETC is “corporate concentration”: that companies involved in nanotechnology are acquiring too much power. And ETC is not alone. In July last year a British pressure group, Corporate Watch, launched a project to map the nanotechnology industry in order to provide campaigners with “individual corporate targets”. In some of its literature, under the headline “Nanotech is Godzilla”, the group talks about the “dark side of nanotech: hazardous substances, military applications and a huge leap in corporate power”. Nanotechnology, like GM, seems to have become a handy tool for corporation-bashing.
Do such fringe groups matter? The lesson of the debate over genetically modified (GM) food was that they can be crucial in influencing broader public opinion, especially where there are worries about human health and the environment. Some of the groups that were involved in successful protests against GM are spoiling for a fight over nanotechnology too.
Moreover, there are signs that some of these concerns are being taken up by more mainstream voices. James Wilsdon, head of strategy at Demos, a British-based think-tank, thinks that nanotechnology needs to be “opened up for discussion”, and questions should be asked such as, “What is the technology for? Who controls it? Who will take responsibility if things go wrong?” And Britain's Cambridge University recently recruited a staff ethicist at its Nanoscience Centre. The head of the unit, Mark Welland, says this is an experiment, aimed partly at ensuring that their scientists take ethical concerns on board. But it also allows the unit to engage with groups such Demos and Greenpeace, and cleverly allows it to be part of the debate rather than its subject.
Many see parallels between GM and nanotechnology, and there have been warnings that the public could reject nanotechnology, as it did GM in Europe. But there are good reasons to think that this time the response will be different.
The main one is that on nanotechnology the views of pro-environment, pro-poor and anti-corporate groups are not aligned. For example, two big environmental groups, Environmental Defence and Greenpeace, are cautiously optimistic about the technology. Doug Parr, chief scientist at Greenpeace, has some concerns, including the health and environmental risks of nanoparticles and its potential use for military purposes. But the very scope of nanotechnology makes it difficult to oppose. As Mr Parr says, “We still don't have a policy on nanotechnology; you cannot on something that is so diverse.” And he adds, “Increasingly we recognise some good things can come from it.” One of the things Mr Parr has in mind is that new materials might bring down the cost of solar cells and thus make solar energy viable and even lucrative.
In fact, nanotechnology has many potential environmental benefits, which makes it hard for green groups to oppose it in principle, as they did with GM. Besides those energy savings, specialised nanoparticles or porous materials might be used to detoxify polluted water, land and even air. And greens can hardly accuse the technology of trying to do something “unnatural” when humans have been modifying substances to create new materials since the Bronze Age.
Pro-poor groups already worry that new materials might result in big changes in demand for commodities such as copper, cotton or rubber, but they too will find nanotechnology hard to oppose because of the benefits it may bring. For example, vaccines might be encapsulated in nanomaterials so that they no longer need to be refrigerated, and water desalination could be made cheaper.
Groups concerned with developing countries are also worried about maintaining access to such technology, pointing to the race now in progress to buy up rights to the key areas of nanotechnology in the hope of bagging a valuable future patent. This may well be a problem, although not one that is unique to nanotechnology. But the battle is not being fought along traditional rich-versus-poor lines; indeed many developing countries are heavily engaged in nanotechnology. Among the more unexpected countries on the list are China, India, South Korea, Brazil, Chile, Argentina, the Czech Republic, Mexico, Romania, Russia and South Africa. Even little Costa Rica is investing in this area.
Because the technology is so new, all these countries see an opportunity for getting a slice of the action, as well as a way of solving long-standing problems. One Indian group is working on a prototype kit for detecting tuberculosis, and the Chinese have developed a scaffold for broken bones that is now being tested in hospitals.
For pro-poor groups, the fight against GM was essentially a fight against America, and more specifically against Monsanto, the company that came to symbolise GM. But nanotechnology already involves a wide range of participants, including the governments of many poor countries. A pro-poor group would probably not be able to exercise much leverage against the nanotechnology research of a country such as China.
Fears that the public might reject nanotechnology have allowed some groups to try a new tack: telling scientists, companies and governments that if they want their technology to be widely accepted, they must “democratise” it. What exactly that means is not clear, except that they are trying to harness public opinion to serve their own particular agenda.
In fact, nobody really knows what the public wants from nanotechnology. According to two recent surveys in America and Britain, most people do not even know what it is. And although they are unlikely to reject it outright once they find out, pressure groups will certainly be able to sway public opinion on some aspects of it. Companies working on nanotechnology applications in new products will need to bear that in mind.