July 2007
send to a friend printable version
Nanotechnology: Protecting workers
Some nanotech companies have developed programs to protect workers by monitoring nanoparticle exposure and watching for signs of nano-related health problems. But the majority do not appear to take such proactive approaches.

Late last year the International Council on Nanotechnology (a consortium of experts from the public and private sectors, including Consumers Union, the nonprofit publisher of Consumer Reports) released a survey of 64 nanomaterial manufacturers and labs. It showed that only about one in three monitored exposure to the substances. About 38 percent believed their nanomaterials posed no special risks, and another 22 percent didn’t know whether they did; the remaining 40 percent said they had safety concerns.

When our reporter toured a plant in Atlanta operated by nGimat, a producer of nanopowders for food packaging, catalysts, and other products, company founder Andrew Hunt said he doesn’t do workplace monitoring and doesn’t consider nanopowders toxic. “Very few nanomaterials have evidence of toxicity other than if the element itself is toxic,” he said.

Not so, says Ken Donaldson, professor of respiratory toxicology at the University of Edinburgh and a leading authority on particle toxicology. Donaldson says scientific evidence shows that “smallness in and of itself” can transform normally benign substances into harmful ones. For example, titanium dioxide has long been used safely as a paint pigment. But animal studies show that nanoparticles of the compound can damage the lungs.

Even scientists who are developing new materials using nanotechnology don’t know enough about the risks, says Maria Powell, a researcher in the Nanoscale Science & Engineering Center at the University of Wisconsin-Madison. “Some of the Ph.D.s think concerns about nanomaterials are being cooked up by a bunch of crazy environmentalists,” says Powell, who has interviewed scientists in many labs.

Researchers at Savannah River National Laboratory have found several instances of risky handling of nanoparticles. Workers at one laboratory, for example, did not know that some nanoparticles are extremely combustible. So they were startled when a rag that contained nanoparticle residues spontaneously burst into flames.

Britain’s Royal Society and Royal Academy of Engineering have recommended avoiding the release of nanoparticles into the environment and urged factories and nanotechnology labs to treat the particles “as if they were hazardous.” But in the U.S., “it’s like the Wild West because people working with or transporting these materials often don’t even know what they’re handling,” says Bill Kojola, an industrial hygienist at the AFL-CIO.

Despite the possible risks, anyone with a credit card can buy carbon nano­­tubes from ­mail-order suppliers such as CheapTubes, in Brattleboro, Vt., whose Web site proclaims, “We search the world for the highest quality lowest cost carbon nanotubes so YOU don’t have to!!!"

We ordered single-walled carbon nano­tubes from CheapTubes, which shipped $150 worth of the powder in an antistatic zipper-locked bag inside a second bag sent in a padded envelope via U.S. Postal Service overnight mail. We sent the package to an outside lab, which verified that it contained nanotubes.

CheapTubes’s president, Mike Foley, says that the packaging is designed to prevent release of nanotubes, and that he has received no reports of bags being torn during shipping. But when we asked Wilson Center science adviser Maynard about the company’s methods, he said “it’s hard to imagine circumstances in which shipping such a powder in plastic bags would be considered good practice."

We also asked Maynard to assess the online version of the safety data sheet that CheapTubes encloses with the shipments. He called it inadequate, saying it doesn’t reflect current research on nano­tubes’ toxicity. Foley says the sheet was the best he could find when the company was started two years ago. At the time of this report, he said he will be amending the data sheet to include more safety information.

 
We create unbiased health ratings to help you make informed decisions. Learn more
FREE Newsletter
Sign up for our FREE updates delivered by e-mail.