Carbon nanotubes are brimming with possibilities, whether used to strengthen damaged cartilage
, act as a drug delivery mechanism
or create plastic that's as strong as steel
. Some researchers, however, are urging caution in handling these tiny particles, lest they enter the lungs of workers in nanotube manufacturing facilities and lodge in sensitive tissue in the throat and lungs.
The logical comparison here is the carelessness with which asbestos was handled for decades, a mistake that cost many workers their lives from mesothelioma, a deadly cancer of the membrane lining the body's internal organs (in particular the lungs) that can take 30 to 40 years to appear. Eager to avoid similar tragedy, industry and academia are probing the potential dangers of nanotubes to nip any in the bud before they become widely used.
Nature Nanotechnology reported
last month that scientists at Queen's Medical Research Institute at the University of Edinburgh/MRC Center for Inflammation Research (CIR) in Scotland found that long, thin carbon nanotubes look and behave like asbestos fibers
"This is probably the most attention a study on this subject has gotten," says Peter Antoinette, CEO of Nanocomp Technologies
, Inc., a Concord, N.H., manufacturer of carbon nanotubes. He adds that common sense is the best approach: You don't want to inhale any microscopic particles, regardless of whether they're made of carbon or asbestos. "If not handled correctly," he says, "flour is dangerous."
Carbon nanotubes have become increasingly popular because of their extraordinary properties. "They're the strongest materials made by man," Antoinette says. "Stronger than steel, lighter than aluminum and a better conductor than copper."
Although much of the Nature Nanotechnology
study resonates with Antoinette, he questions some of the methods the researchers employed. For example, the carbon nanotubes were injected into the stomachs of the lab animals they tested. "I'm not sure that's truly representative of inhalation," he says.
readers praised attempts to shed light on the potential dangers of carbon nanotubes but were hesitant to write off such a promising technology. "I agree we should look into this more closely," commented Karen Garvin
. "However, that doesn't mean we should halt all study or use of nanotubes out of fear of the unknown. As a society, we either tend to ignore or overreact to environmental concerns."
Another reader, Hugh Jones
, pointed out that carbon nanotubes are just one of many technologies whose impact on health is unclear at this time. "We don't know with certainty the long-term effects of cell phones, plastic bottles and the like," he wrote. "So it's good to see someone sounding the alarm for potential dangers like this before they cause grievous harm. Or perhaps the dangers mentioned here will motivate the companies to create a safer product."
Of course, the debate is as hypothetical today as it was a decade ago
, when Science
first likened carbon nanotubes to asbestos, stirring debate among pathologists, nanotube chemists and asbestos researchers who disagreed on the extent of the danger posed by exposure to carbon nanotubes. Let's hope further investigation of carbon nanotubes reveals ways to harness their potentialâ€”as well as mitigate their risks.