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Nanotroubles
October 11, 2004
Toronto Star

It's a small wonder and a big mystery.

Nanotechnology - a field dedicated to science of the very small - holds great promise for the future of medicine, energy production, electronics, cosmetics and coatings. By manipulating molecules, researchers say they can make drugs more effective, solar cells more efficient and sunscreen more potent.

With a wealth of future applications, the hype surrounding nanotechnology rivals the dot-com buzz of the 1990s.

Nanotech, it seems, is the next big thing.

According to Lux Research, more that $8.6 billion (U.S.) will be spent on nanotechnology research and development this year. And that's just the beginning. Over the next 20 years, the U.S. National Nanotechnology Initiative estimates nanotech will generate $1 trillion (U.S.) around the world.

One reason for the big figures is nanotechnology's broad definition. The term nanotechnology basically covers everything measuring less than 100 nanometres that can be engineered through the manipulation of molecules and atoms. Such things are much smaller than the width of a single human hair: one nanometre is equal to a billionth of a meter. At that size, elements react quite differently than they would in larger forms. Nano-sized particles (nanoparticles) tend to be more reactive, for example. Some nanoparticles can also pass through cell membranes, interacting with the human body in new ways. Researchers say they can harness these powers for the good of mankind.

Unfortunately, the safety of the science isn't fully understood.

Questions linger about the toxicity of some oft-hyped nanoparticles. Researchers say they aren't sure how the little balls and tubes of carbon will impact humans and the environment. Preliminary research suggests some nanoparticles could cause breathing problems, brain damage and alter DNA.

"We're not saying it's necessarily more toxic, we're just saying it's unknown," said Ann Dowling, chair of a British committee that recently tabled its report on potential impact of nanotechnology.

Despite the uncertainty, a handful of products that contain engineered nanoparticles are already on store shelves.

Inside every bottle of Oil Of Olay Complete UV Protection are tiny particles of zinc oxide. Zinc has long been used as a sunscreen in larger form. It's effective, but certainly not for the vain: it stays white on skin. Make those particles nano-size and there's no more risk of embarrassing white marks.

But some researchers worry that the nanoparticle intended to protect the skin might actually damage DNA.

A July 2004 report commissioned by the British government cited studies that found microfine zinc oxide damaged cells in vitro.

Whether the particles are toxic to cells in a living body is still unknown. The report, written by the British Royal Society and the Royal Academy of Engineering, said more research was needed before the particle could be considered safe for use in cosmetics.

Procter & Gamble declined to answer questions about the product's safety.

Health Canada said it has not yet studied the issue.

The lengthy U.K. report didn't stop at sunscreen. It also questioned the safety of engineered airborne nanoparticles, in light of air pollution research.

Nanoparticles aren't only engineered by crafty humans, they also occur naturally. Your average fire produces lots of nanoparticles, as does a combustion engine.

With little research on engineered nanoparticles, the Royal Society turned to studies of air pollutants to garner some insight into potential toxicity.

According to the study, research into air pollution indicates "cells and organs may demonstrate toxic responses even to apparently non-toxic substances when they are exposed to a sufficient dose in the nanometer size range."

Nanotubes - tiny structures shaped like drinking straws - also have physical similarities to fibres known to cause lung disease.

"Given previous experience with asbestos, we believe that nanotubes deserve special toxicological attention," the report stated.

Right now, carbon nanotubes aren't engineered in any great quantities. Lab workers are likely the only people who might be exposed to this particular kind of nanoparticle. It is hoped that the toxicity of the tubes can be determined before commercial production of nanotubes gets underway, so that regulators can properly address issues surrounding exposure and disposal.

Without proper disposal, manufactured nanoparticles could also impact wildlife.

A recent study in fish found they were affected after only 48 hours of exposure to carbon nano-particles known as fullerenes. Eva Oberdorster, an environmental toxicologist with Southern Methodist University in Dallas, Texas, looked at three tissues in her study of fullerene-exposure: the brain, liver and gill. She concluded that the uncoated fullerenes caused brain damage and liver inflammation in the exposed fish.

Environment Canada said additional studies would be required before it would consider taking action.

Oberdorster is currently heading up another study that will look at the impact of single-walled, carbon nanotubes on fish. She expects to have the results for that study early next years. Like many researchers in the field, Oberdorster says more resources are needed for toxicity research.

"If you look at the actual numbers, (the U.S. federal government) spends nearly $1 billion (U.S., annually) on developing products, and $10 million for toxicity. That's pretty silly. It's a minor fraction [about 1 per cent] of the over-all expenditure," she said.

Actually, the amount of money dedicated specifically to toxicity is even smaller. Cate Alexander, communications director for the U.S. National Nanotechnology Co-ordination Office, confirmed that the $10 million is for risk assessment over-all, of which toxicity is only one part. Some of that $10 million is spent on other important areas of risk assessment research, such as how to safely transport nanoparticles.

Canada has also made a substantial investment in nanotechnology. It is not as clear, however, how much of an investment the government will make into studies concerning its safety.

The recently established National Institute for Nanotechnology (NINT) will investigate nanotech applications in a specially designed facility in Alberta. In the first five years, NINT will receive $120 million from Canada's National Research Council, the government of Alberta and the University of Alberta. The federal government has committed $12 million a year in funding starting in year six.

None of that money is earmarked for research into the toxicity of nano-size substances, however.

"It's not our mandate to study toxicity," said Bill Cowley, director of implementation for the NINT. "There are other labs in Canada who currently do that kind of work."

Cowley said Environment Canada and Health Canada are normally responsible for toxicity research. But he said some of the work done at the NINT could prove useful to regulators looking to identify and measure exposure to nanoparticles.

"The challenge in nanotech is that it's so difficult to actually see a nanoparticle. The NINT will be developing detection capabilities that can be used to characterize nano substances ... and we will share our expertise with other (government) departments and industry."

The Canadian Institutes for Health Research (CIHR) also funds nanotechnology research, primarily regarding its use in medicine. But yet again, toxicity issues are not considered a priority.

Eric Marcotte, team lead for the CIHR's Regenerative Medicine and Nanomedicine said toxicity studies could be funded by the government agency, if they were ranked highly by a peer review panel. But Marcotte said he didn't believe any such proposal had yet been submitted.

Besides, he said, toxicity is normally Health Canada's domain.

That government agency is still "gathering intelligence" on the subject.

According to a written statement issued by Health Canada, "a foresight initiative has been established within the department to gather intelligence on new and emerging technologies, including nanotechnology, and to assess what its impacts might be on the regulatory system. This allows Health Canada to monitor the issue and fulfil its responsibilities for protecting and enhancing the health and safety of Canadians."

Environment Canada is also still considering its response to the small science.

"We have not assessed engineered nanoparticles," Environment Canada said in a written statement. "We are however doing a global scan/assessment/analysis, the results of which will help to calibrate future Environment Canada responses to nanotechnology."

The agency said it expects to complete its fact-finding mission by the end of March.

Under current regulations, Environment Canada and Health Canada assess the safety of new substances. The catch is, the agency has to identify them as new. According to Environment Canada, certain nanoparticles have new names and identification numbers - hence they have to be assessed even if the same substance has already been approved in a larger form. It's not clear, whether nanoparticles are required to be listed under a new, unique name.

Dowling and other researchers would like to have regulations in the U.K. changed so that new nanoparticles don't slip through the regulatory cracks.

You can't infer the behaviour of nanoparticles from that of the larger version, she said.

You also can't infer the toxicity of all of nanotechnology based on the effects of one or two particles.

Dowling worries that without enough research and proper public consultation nanotechnology as a whole will get a bad rap, much like genetically modified food.

The U.K. report clearly states that some forms of nanotechnology - particularly that associated with computers - do not present "any unique hazards" that can't be handled by existing legislation.

Nanoparticles used in other applications could also be tweaked to avoid toxic effects. A recent study of fullerenes conducted at Rice University's Center for Biological and Environmental Nanotechnology in Texas found it is possible to greatly reduce toxicity to human cells by adding other molecules to the outside of the little carbon ball.

The ETC Group in Ottawa, a research organization dedicated to environmental issues, has called for a moratorium on all research into nanoparticles until a protocol for lab safety has been established.

"It shouldn't take more than a few weeks," said ETC Group executive director, Pat Mooney.

Despite her findings in fish, Oberdorster doesn't think there should be a moratorium on the use of nanoparticles.

"There's so many positive benefits coming from fullerenes, especially in the area of fuel cells," she said. "If we can get away from fossil fuel, that would be awesome."

Dowling hopes that instead of a moratorium, the U.K. will establish a research centre to focus on nanoparticle toxicology, measurement and routes of exposure.

"With nanotech, it's only in very small scale of production at the moment. We've got time - if we begin now - to engage the public about the benefits and the risks," Dowling said.

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