Sunday, April 09, 2006

Nanotech: Seat-Of-The-Pants Occupational Health Experiment

What does this sound like?
Men in grease-stained blue coats navigate catwalks atop hulking, two-story-tall spray-drying machines. Forklift drivers steer 55-gallon drums of chemicals from one area to another. Other workers attend to noisy milling operations, their face masks gathering a thin film of pale dust as they empty buckets of freshly made powders
Sounds like you're average factory anytime in the last hundred years, but it's actually an ultra-modern nanotech facility -- and the new technologies are worrying occupational health experts.

The Washington Post had a long, intresting article today about the possible health effects of working with nanotechnology, things like: "precision-engineered carbon "buckyballs" one-ten-thousandth the size of the head of a pin and microscopic nanospheres that can pack the power of a car battery in a napkin-thin wafer."

Post journaist Rick Weiss has some knowledge of past occupational health failures which unions and scientists are trying to avoid this time around:
Occupational settings have often served as bellwethers of toxic trouble. A spate of skin cancers in radiologists 100 years ago revealed the link between X-rays and cancer. "Mad hatters," who worked with mercury-exposed felt, demonstrated that metal's neurotoxic effects. And the link between asbestos and lung disease first came to light in workers handling the fibrous mineral.
And we might also want to mention lead, vinyl chloride, chromates, pesticides and on and on.

Some of the possible human hazards of nanotech that have been identified or suspected include:
  • Their ability, identified in animal stuides, to clog airways, trigger intense immune-system reactions and toast living cells.
  • Some nanoparticles that behave like little ball bearings can cause slips and falls

  • They can be hundreds of times more combustible than common, micron-size particles, raising the possibility of explosion.
A previous Washington Post article identified other hazards as well:
  • Lab animal studies have already shown that some carbon nanospheres and nanotubes behave differently than conventional ultrafine particles, causing fatal inflammation in the lungs of rodents, organ damage in fish and death in ecologically important aquatic organisms and soil-dwelling bacteria.

  • Researchers at the New Jersey Institute of Technology found that nanoparticles of aluminum oxide stunt the growth of roots on several crops -- including soybeans and corn, mainstays of U.S. agriculture.

  • And a California team working with laboratory-grown cells showed that carbon nanotubes specifically activate "cell suicide genes."
Scientists from the National Institute for Occupational Safety and Health are making a valient effort to study the problem. They're being assited by Altair Nanotechnologies Inc.
The inspection was at the invitation of the company's chief executive, Alan Gotcher. Unlike many of his corporate peers, who have kept their heads down amid a flurry of questions about what, exactly, they are making and how they are assuring worker safety, Gotcher thinks the industry should share what it knows about nanotech manufacturing methods and safety strategies.

"We need to be responsible and we have to be proactive, and if we've got products that have problems, we've got to do something about it," Gotcher said. "On the flip side, we should not let fear of the unknown cause an overreaction."

Some of the problems NIOSH is facing include:
  • Scientists don't know what to focus on:
Is it the number of particles a person is exposed to that matters most? Is it their chemical composition or size? Or, as recent research suggests, is it the total surface area of each intricately etched nanoparticle -- a complex spatial dimension that instruments can barely measure?
  • No applicable safety or health regulations: The only thing close that OSHA has is its "nuisance dust" standard, but it's not exactly appropriate to nanohazards:
Just three weeks in a workplace with that level of engineered nanospecks would be equivalent to the exposure that caused animals to choke to death in experiments in 2004, Balbus said.
  • They need to figure out how to measure worker exposures and whether it can be done cheeply enough for small businesses.
A central goal of the NIOSH visit was to compare readouts from the agency's cumbersome and expensive instruments with those from cheaper, handheld devices, to see if the latter can suffice.

"We want to know if you can do this without a $75,000 piece of equipment and 6 PhDs," said NIOSH scientist Mark Hoover.
  • What kind of personal protective equipment, like respirators and gloves, will adequately protect workers?
Preliminary studies on latex gloves suggest outright holes, or pores, large enough to allow nanoparticles through may be rare. But definitive studies have yet to be funded.

Similarly, a few studies have suggested that high-quality respirators can trap 95 percent of nanoparticles. But "whether 95 percent efficiency is good enough or not is still open to discussion," said Hung Min Chein of the Industrial Technology Research Institute in Chutung, Taiwan, who is studying the issue.
  • Funding problems:
Government and private sources are expected to invest about $4 billion in nanotech this year. Less than 10 percent of that is focused on potential risks -- with most of that going to general toxicology and environmental impact studies. Only NIOSH is focused specifically on nanotech workplace issues -- a task it has had to accomplish with about $3 million a year it cobbles together from its general budget.
  • Lack of an overarching strategy:
Research so far has produced a patchwork of results that largely reflect individual investigators' interests. Many experts want to see a national or even international plan that would rank the most pressing health and safety questions and allocate money to get them answered.
Despite the obstacles, NIOSH scientists are determined:
"We don't want to be sitting around 20 years from now saying, 'Gee, I wish we had looked into this,' " said Charles Geraci, a NIOSH branch chief who was part of the team visiting Altair.
Of course, all that is well and fine. We definitely need the science -- and much more funding to study the problem. But the real battle will come down the road. How much evidence of a hazard is needed before safe practice guidelines and legally enforceable standards need to be seriously considered? We have written frequently about the chemical industry's war against environmental and occupational health science, and their campaigns to "manufacture doubt" in the science. And how fiercely will the nanotech industry fight government regulations when the time comes?

A previous Washington Post article described the frustration of the environmental community at the Bush administration's apparent preference for voluntary EPA standards addressing some of the environmental hazards of nanotech. Given this administration's aversion to mandatory regulations, it wouldn't be surprising if the same voluntary approach is followed at OSHA.

Happily, by the time we get to that point, the Bush administration will be a distant bad memory. Hopefully something better will have replaced it.

More information on the hazards of nanotech can be found at NIOSH's website and at Hazards Magazine.

Related Article

Nano Hazards, December 5, 2005