Nanotechnology: Big trouble in the mini-revolution?

Nanotechnology has been hailed as a potential cure for cancer and environmental ills. But could it become the asbestos of the 21st century?

Researchers and futurists believe that nanotechnology could transform everything from healthcare and manufacturing to environmental clean-up and space travel. Many of the worst problems threatening us, they say, could be eradicated this century.

Cancer cells could be destroyed by tiny silicon combs; "nanobots" could clear blocked blood vessels. Hydrogen-based fuel cells using "nanotubes" could allow cars to travel 5,000 miles on a full tank. Minute solar cells in building façades and on road surfaces would produce cheap energy.

Nanoparticles might detoxify petrochemical waste. There could be a new industrial revolution as atoms are assembled into useful new products.

But at scales of a millionth of a millimetre, materials can develop unusual and unpredictable properties, leading to concerns about risks to health and the environment. Some experts are calling for a moratorium on nanotechnology, saying that ultra-fine particles created for cosmetic, industrial and high-technology uses could prove deadly.

Bob Phelps, director of the Australian lobby group GeneEthics, says: "Each type of nanoparticle may be as deadly as asbestos." In his opinion, 25 per cent of the investment in nanotechnology should be spent on researching risks.

Friends of the Earth estimates that, in Australia, 300,000 workers in refining and welding could be exposed to nanoparticles; a further 33,000 may be exposed through handling powders, mainly in the pharmaceutical and cosmetics industries.

Like Phelps, Friends of the Earth supports a moratorium on research, development and manufacture of synthetic nanoparticles until regulations are developed. "This could prevent huge human and financial costs and compensation claims from injured persons, as has been seen with asbestos," it told an Australian senate committee inquiry.

Similar calls are being heard in America. At an Environmental Protection Agency nanotechnology workshop in October, Mihail Rocco, co-chair of the National Science and Technology Council, declared that: "Federal agencies lack methods to monitor environmental releases of nanoparticles. Yet they can go to the brain and potentially cause damage."

Another presentation explained that nanoparticles can pass through the skin, causing inflammation and other potential hazards. Products meant to be applied to the skin, such as sunscreen and baby productsinclude nanoparticles.

There is concern in the UK about the possible dangers. Last year, the Government commissioned a report by the Royal Society and Royal Academy of Engineering into the new science. It concluded that there were no significant concerns, but said there were areas where more research should be conducted.

The Department for Environment, Food and Rural Affairs announced last month that it would be ploughing £5m into investigating the health risks of nanotechnology. Researchers will look at how nanoparticles travel through the environment and human body, and how they might affect health.

Defra's approach is understated. But a 2004 report from the Switzerland-based reinsurer Swiss Re makes a far more urgent case. It states that, once in the blood, "nanoparticles can move practically unhindered through the entire body". During pregnancy, nanoparticles would be likely to enter the foetus.

Nanoparticles, it continued, may harm living tissue in at least two ways - through chemical reactivity, or by damaging phagocytes, or scavenger cells. Nanoparticles may disrupt the immune system, cause allergic reactions, interfere with cell communications, or alter enzyme exchanges. Water filters will not remove nanoparticles, and they could perhaps penetrate plant roots and enter the food chain.

But according to the German drugs and chemicals group Beyer Research, nanotechnology doesn't pose any greater threat than established technologies. "Any new technology is associated with risks. Stone-age man discovered the hand axe, but the tool was also a powerful weapon," it says. "In any case, there's no sense in elaborating frightening scenarios that are as misleading as naive promises that 'the whole thing's harmless'. It would be more effective for the development of this new technology to be accompanied by education and critical examination."

The American technology commentator Jeff Harrow believes that we should resign ourselves to nanotechnology. "Even if some governments were to ban or restrict nanotech research," he says, "others would encourage it through enhanced education and funding to help them gain a nano-edge."

Department for the Environment, Food and Rural Affairs (Defra): www.defra.gov.uk/environment/nanotech/index.htm; Science Museum: www.sciencemuseum.org.uk/antenna/nano/

Tomorrow's world

Nano clothes

Nanotechnology is transforming clothing. Synthetic materials draw moisture away from the skin, just like cotton. Spills roll off. Stains are easily washed out.

Nano sport

Shock-absorbing shoes make for smoother landings, balls keep their pressure longer, and stronger tennis rackets and golf clubs can deliver straighter shots. The top golfer Padraig Harrington helped to develop new clubs strengthened with carbon nanotubes.

Nano at home

Nearly 15 years ago, the nanoscientist and tech visionary Eric Drexler predicted that smart materials would become part of everyday life. Paint would change colour on demand. Video wallpaper would replace televisions. Some of these ideas are already prototypes.

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