Andrew Maynard
In looking toward the future of nanotechnology safety research, Andrew Maynard first took a step back in time — seven years, to be exact.
It was 2004, and a globe-spanning group of scientists and policymakers were gathered in Buxton, England. The meeting produced a thick report, including 69 recommendations aimed at promoting responsible development of nanotechnology, which leverages super-small particles to do often amazing things.
Maynard made a word cloud (pictured) of the 2004 report. What stands out are familiar terms that still trouble today’s researchers: “risk,” “exposure,” “control.”
This year, the fifth edition of the International Symposium on Nanotechnology, Occupational and Environmental Health drew hundreds of attendees, from more than two dozen countries. On the final day of the conference, Maynard flashed history on the screen to illustrate a simple question: Have we made progress, or are we going in circles?
“If we look through those [recommendations], a lot of them look remarkably similar to those questions we’re asking today,” said Maynard, now the director of the Risk Science Center at the University of Michigan.
The answers, from a diverse panel of experts, were at once critical and hopeful.
Paul Schulte, a top official at the National Institute for Occupational Safety and Health, said there has been progress. But, he added, he’s concerned that manufacturers aren’t yet completely bought in to using the safety measures needed for proper development.
“There’s not enough emphasis on the end of the pipeline,” he said.
Barbara Herr Harthorn, director of the Center for Nanotechnology in Society at the University of California, Santa Barbara, called safe development of nano-enabled products a “moving target.” One of the key terms in the field these days is “responsible development,” which means pushing manufacturers to use nanotechnology in the safest ways, to do the most useful things. But while there’s lots of talk, she said, “we don’t take as a given that we know what that means.”
Others expressed concern that the work safety specialists are doing is not spreading into other segments of the nanotechnology world, raising questions about whether those developing new products understand the risks they may be taking — or passing on to consumers.
“Insights that this community has gained have not been adequately disseminated to the rest of the science and engineering community,” said Hilary Godwin, a professor and researcher at the University of California, Los Angeles. “We need to make sure were working hand-in-hand.”
Nanotechnology leverages super-small particles (a nanometer is a billionth of a meter) to create new products. These materials can make bike frames lighter and stronger and sunscreen more transparent on the skin, as well as new medical instruments and medicines that can save lives.
There is broad agreement that nanomaterials have lots of potential for a wide variety of applications. But shrinking these substances can change their properties; scientists are struggling to figure out whether, how and why that shift can make them dangerous in the process.
Looking around the crowded ballrooms at the symposium — hosted by the University of Massachusetts Lowell and the school’s Center for High-Rate Nanomanufacturing and Toxics Use Reduction Institute, it was clear that safety has an important seat at the table. There’s no question that it’s a major shift since the 2004 Buxton gathering. Research dollars, once concentrated on spurring innovation, are flowing into scrutiny of a broad array of nanomaterials, from carbon nanotubes to super-small silica.
Yet while there are scores of scientific papers suggesting that some of these ultra-tiny substances can affect people, animals and the environment, there are still a slew of unanswered questions. How important is size, as opposed to the surface area, of a single particle? There seem to be crucial differences in how the exposure method (e.g., inhalation vs. swallowing) affects what these materials do to cells and organisms. There are also basic questions of scientific methodology, including whether running experiments with very high doses of the substance under review yield skewed results.
Practical concerns abound, too: how to minimize the impact on workers, and how to best inform consumers without scaring them. These issues are pressing, because hundreds of products that use nano-sized materials are already on the market.
So far, the cautionary measures are mostly voluntary. While NIOSH issued a recommended workplace exposure limit for carbon nanotubes last year, it’s a suggestion, not an edict. Some states are taking stronger steps, and an alphabet soup of federal agencies, including the Food and Drug Administration and the Environmental Protection Agency, are looking hard at everything from athletic clothing impregnated with anti-bacterial nanosilver to cancer drugs that use super-small gold particles.
Godwin praised some of the EPA’s work, especially involving carbon nanotubes. The tiny carbon cylinders are prized because of a host of useful qualities, including the ability to conduct electricity. But their needle-like characteristics have drawn comparisons to asbestos because of evidence that they can lodge in the lungs and cause potentially harmful inflammation.
What the EPA isn’t doing well, Godwin said, is keeping the public apprised of what it’s doing.
“The level of transparency in terms of how that translates … is not what it could be,” she said.
In other areas, such as developing ways to study these materials, there has been real progress. There’s also an emerging trend of new matrices for assessing the immediate risk of a nanomaterial, whether it’s to a graduate student working in a laboratory, a factory worker or a consumer. These frameworks are being designed simplify the long, arduous process of figuring out what’s safe or dangerous and distilling it into a series of dots, a wall poster, or other easy-to-understand format.
But a better grasp of danger isn’t helpful if the red flags are ignored, Schulte said. That’s where his concerns come in about whether manufacturers are taking the advice of toxicologists.
“We will come a long way to saying ‘Yes, this is responsible development,’” Schulte said. “Without assessing compliance, we are shooting in the dark.”
The group is scheduled to gather in Japan in 2013. What will the word cloud look like then?
Many on the panel said they thought there would be more to be excited about. International collaborations are gaining traction, and more sophisticated toxicological studies are blooming like mushrooms in labs around the world. A key element for future success, according to several members of the panel, is communication — between governments, with industry and with the public.
“I think it’s the social risks, not the technological risks, that imperil the development of nanotechnology,” Harthorn said.
