The 'grey-goo' gang takes on humanity's little helpers

三月 21, 2003

Stephen Phillips asks if scare stories will stifle nanotechnology at birth.

If there is a road map for solving today's most pressing material and medical ills, chances are it will run straight through the infinitesimal realm of nanotechnology. Occupying a dimension dwarfed by the eye of a needle, it holds out hope of fashioning sustainable energy sources, ending pollution, boosting computing power exponentially, even curing cancer, researchers say.

Ushered in by advances in microscopy, materials science, organic chemistry, engineering, condensed-matter physics and molecular biology, the very building blocks of matter become like Lego bricks in scientists' hands. It is a nether world where classical physics no longer applies and quantum mechanics kicks in. Scientists hope to harness the unique properties of structures at this scale to design - atom by atom - desired characteristics into materials to make them stronger, lighter or more resilient.

"It is simply the maturation and convergence of physics, chemistry and engineering. The impact of what these fields can do is determined by what they can do at the nanoscale," says Richard Smalley, professor of chemistry and physics at Rice University, Texas, who shared the 1996 Nobel prize for chemistry with Sir Harry Kroto and Robert Curl for discovering that vaporised carbon molecules condense into very stable crystals in an inert gas. These so-called buckyballs paved the way for the development of carbon nanotubes, prospective applications of which include data-storage components able to host trillions of bits of information on a pinhead-sized gadget and diagnostic and drug-delivery systems deployable in the body to detect and treat cancers.

Around the world, political leaders have embraced the promise of nanotechnology. In the US, research and development spending swelled from £268 million in 1997 to £374 million last year, and Japanese funding rose from £74 million to £465 million in the same period. This year, the US has earmarked £484 million in research grants, and European Union governments have pledged £740 million for 2003-04. Nanotechnology is blossoming on campuses, and dedicated research centres are proliferating. The field's momentum seems assured.

A decade ago, agricultural biotechnology looked similarly unstoppable, with its promise of higher crop yields and weed-resistant plants among other benefits. Then it ran into well-organised European activists, opposed to genetically modified ingredients entering the food chain. Anti-GM lobbying struck a chord with a public rattled by the BSE crisis. Research efforts were stung by charges that scientists were peddling "Franken-foods".

Sabotage of research sites, attacks on companies and consumer boycotts exacted a huge toll on the nascent field.

Science watchers detect early signs of a similar groundswell of opposition darkening nanotechnology's horizon. The opening salvo in what was recently diagnosed as a "backlash" in the journal Nanotechnology was fired in April 2000 by Bill Joy, chief scientist and co-founder of computing giant Sun Microsystems.

As an architect of the Unix computer operating system, Joy makes an unlikely technophobe. But in a cover story for Wired magazine, he spun out a dystopian scenario of hordes of mutant nanoparticles wreaking genocidal havoc. Joy took aim at one of the biggest hurdles to delivering on the promise of nanotechnology - the need to scale up in orders of magnitude from the individual molecules that researchers tinker with today to devices incorporating millions of molecules. A theoretical solution to the so-called fat-fingers problem, sketched out by Eric Drexler in his influential 1986 nanotechnology manifesto, Engines of Creation , would be to design nano-scale robots to do scientists' bidding. Joy took this as his cue to conjure the spectre of "nanobots" replicating beyond control and advancing on humankind in an encroaching tide of "grey goo".

In the same vein, Michael Crichton's Prey , published in November, borrows from Drexler's vision to project a similar grey goo-filled doomsday. A movie tie-in is reportedly in the can, and the box-office pull of Jurassic Park 's author is likely to guarantee another Hollywood blockbuster.

Opening another front against nanotechnology, the Action Group on Erosion, Technology and Concentration (ETC), a self-styled environmental advocacy group, issued an 80-page broadside in January, stigmatising nanotechnology as "The Big Down". Citing concerns about possible toxic side-effects of nanomaterials, the group called for a moratorium on research while safety protocols are hashed out. Eschewing grey goo, ETC says the real threat is green goo, from self-assembling organic molecules. "It's not a matter of making mechanical devices that self-replicate - living material such as yeast, fungi and rodents take care of the whole problem of self-replication [more easily]," says Pat Roy Mooney, ETC's executive director.

Nanotechnology researchers concur that the science underpinning such phantasmagoric extrapolations is flawed. "Self-replicating machines are not something we should worry about - there are no demonstrations in the lab.

It's not even what a lot of us are working on," says Vicki Colvin, director of Rice's Centre for Biological and Environmental Nanotechnology. There's no evidence that green goo is any less conjectural, she adds. However, the plausibility of nano-Luddite fears may be beside the point.

Scientists disinclined to dignify such far-fetched projections for fear they might lend them credence should beware the price of silence, says Peter Singer, director of the University of Toronto's Joint Centre for Bioethics and co-author of the Nanotechnology article. "These arguments certainly exercise the public."

He sees a gaping ethical vacuum at the heart of nanotechnology, providing fertile ground for critics and "a GM food-style showdown". This is crystallised in the paucity of studies commissioned into the social implications of nanotechnology and lack of engagement with the public about where research is headed, he says. To fill the vacuum, Singer says, scientists need to reach out to the public.

Researchers seem receptive to this. "Every time scientists get a chance, they should talk [up nanotechnology]," Smalley says. Paul Alivisatos, professor of chemistry and materials science at the University of California, Berkeley, favours delegating to interested members of faculty to educate the public. But accelerating ethics also entails anticipating and legislating for hypothetical dilemmas, Singer adds. "One needs ethical reflection from the start of the development of technology - it can't be an afterthought."

Early nanoethics fodder might include "intelligent machines you can't see", Colvin suggests. "This 'invisible' adjective brings forth ethical issues about ownership and surveillance." But Mihail Roco, director of the National Nanotechnology Initiative, which administers US funding, argues that discussion of speculative risks is premature. "The field is in an exploratory phase. There's a lot of potential, [but] we can't tell what measures to take to cope with consequences in five to ten years."

Colvin says that although scientists shrink from such discussions with peers, they must be mindful of different rules of engagement with lay people. "As a technical person, you want to make a decision after all the data come in, but this is not the way the world works." Scientists dismiss activists such as ETC at their peril, she adds. Amid its rhetoric, Colvin acknowledges that ETC raises valid concerns about the implications to ecosystems and people of introducing nanomaterials into the environment.

While such concerns are on the worry-wart end of the public-opinion spectrum, they are not aberrant, she says.

Smalley, for one, is not persuaded that nanotechnology warrants special vigilance. "Yes, nanomaterials may not have existed before, but we have had many examples of this in the past century." But, more hawkish on risks, Colvin says that, ultimately, about 10 per cent of nanotechnology spending should be devoted to toxicology studies, compared with current negligible funding.

Meanwhile, ETC is pressing hard its case for suspending nanotechnology research. It might be a shoestring outfit run from the remote Canadian prairie city of Winnipeg by a high-school dropout with no formal science training, but Mooney is an indefatigable networker and adroit political operator. Last month, he met Indian politicians to spread his message.

Before that, he had an audience with Brazilian ministers, and in June he will address EU parliamentarians.

Sceptics of ETC's capacity to be a powerful thorn in the side of the nanotechnology community should look to the former focus of the group's attacks, Monsanto. In its previous incarnation as the Rural Advancement Foundation International, ETC waged a savvy public-relations battle against the biotechnology behemoth. Coining the catchy term "terminator" to describe the technology Monsanto used to render GM seeds sterile, the public outcry Mooney stirred up led the firm to scuttle plans to market the technique.

In fact, Monsanto offers a salutary lesson in how not to deal with critics, Colvin says. "At first, there was a free-flowing dialogue with ETC. But then the corporation locked down." This proved its undoing. It sowed distrust, allowed the company to be portrayed as sinister and unscrupulous, and incited foes. Lines of communication must be kept open, Colvin says.

But Smalley believes that parallels between biotechnology and nanotechnology can be overstated. "After all, we're not advising that you eat nanotech stuff," he notes.

Part of reducing nanotechnology's vulnerability may lie in distancing serious research from the starry-eyed claims for its utility as a universal panacea that are made by futurists on the field's fringes. Recklessly inflated utopian visions tend to encourage correspondingly outlandish pessimistic scenarios, Colvin says.

A gentle reminder that nanotechnology, for now at least, is far from being a silver bullet and that much of its promise remains on the drawing board may be prudent. Ultimately, growing public scrutiny and new public-relations awareness for researchers reflect nanotechnology's coming of age, Alivisatos says. "It's a new situation for us - no one cared about nanotechnology ten years ago." The stakes of not explaining the revolution afoot are clear, he adds. "It would be a shame if a technology that could help us discover cancer before it's more than a few cells and develop new material for data storage was lost because it was misunderstood."

A meeting jointly organised by the Royal Institution, The THES , the Biotechnology and Biological Sciences Research Council and the Institute of Nanotechnology to debate the issues raised by nanotechnology is being held on March 25. Tickets have sold out.

BIG DATES, TINY FIELD

1959
The first molecular machine is revealed with Max Perutz's discovery of the structure of haemoglobin.

Physicist Richard Feynman gives "There's plenty of room at the bottom" lecture, outlining the possibility of molecular engineering and issuing two challenges to take the field forward

1960
Creation of an electric motor 1/64th of an inch cubed, which meets one of Feynman's challenges

1962
Perutz receives the Nobel prize in chemistry for his work on haemoglobin

1974
Term "nanotechnology" invented by a scientist at the University of Tokyo

1981
Eric Drexler publishes key ideas on the prospect of creating artificial molecular machines through the use of custom-folded proteins The scanning tunnelling microscope allows individual atoms to be moved about

1985
Page of a book is shrunk to 1/25,000th scale and read by electron microscope, meeting Feynman's second challenge

1985
Production of C60 buckyballs, or fullerenes, which provide scientists with useful molecular building blocks

1986
Invention of atomic force microscope, which can manipulate individual atoms.

Gerd Binnig and Heinrich Rohrer receive Nobel prize in physics for inventing the scanning tunnelling microscope.

Drexler publishes seminal work on nanotechnology, Engines of Creation .

1989
Scientists spell out the letters "IBM" with 35 xenon atoms on a nickel surface

1991
Discovery of carbon nanotubes by the Japanese scientist Sumio Iijima

1996
Sir Harry Kroto, Richard Smalley and Robert Curl receive the Nobel prize for chemistry for discovery of fullerenes

1997
Sir John Walker and Paul Boyer share Nobel in chemistry for showing how the ATP molecule provides the energy for life

1998
Creation of molecular motors with a single propeller-shaped molecule spinning at their centre

2001
Advances in nano-scale electronic circuitry win the journal Science 's breakthrough of the year prize

2010?
Invention of device that can put molecules together to form nanomachines

2030?
Nanomachines devised that can repair damaged cells in the human body

2040?
Computers the size of bacteria created to handle data far faster than their counterparts today

 

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