Nanotech Under the Microscope

From wrinkle creams to wrinkle-resistant pants, products
containing tiny manufactured particles have already infiltrated the
marketplace. They’re among the first commercial uses of
nanotechnology — the emerging field of manipulating matter on a
scale so small that new substances can be built from the atomic
level up. Nanotechnology is already touted for its use in new
super-strong materials, medical treatments, and other areas.
Supporters say it is poised to usher in a revolution as massive as
the computer age.

Yet even as the nanotech industry rushes ahead, concerns about
ultrasmall particles are mounting. A growing number of studies
suggest that they could have troubling effects on human and
environmental health.

A nanometer is one billionth of a meter, or about the length of
10 hydrogen atoms in a row. Nanotechnology is usually defined as
work on a scale of less than 100 nanometers. The emergence of
nanotech reflects a growing knowledge of how materials behave at
the atomic level, where the laws of nature get quirky and a
material’s properties (like conductivity and strength) can be
vastly different than at larger scales. That’s what makes it all so
tantalizing to some researchers — and worrisome to others.

Numerous studies suggest that nanoparticles can be toxic simply
because they are so small. Vyvyan Howard, a
toxicopathologist at England’s University of Liverpool, recently
conducted a review of past research studies and found that, at the
nano scale, a particle’s toxicity is related more to its size than
to the material from which it’s made. Nanoparticles can be
ingested, inhaled, and absorbed through the skin. They also appear
to cross the blood-brain barrier, nature’s adaptation for blocking
foreign substances in the bloodstream from reaching and disrupting
the central nervous system.

The most recent concerns have focused on the fullerene, a
nanoparticle named after architect Buckminster Fuller, inventor of
the geodesic dome. Fullerenes are cagelike molecules formed of the
element carbon that look like soccer balls. In a recent study
conducted by researchers from Southern Methodist University in
Dallas, largemouth bass exposed to these ‘buckyballs’ in water for
only 48 hours developed brain damage tied to the breakdown of
lipids, a common cell compound. Although no commercial products now
contain buckyballs, some do contain a related substance — strong,
cylindrical, threadlike structures known as carbon nanotubes.
Studies have linked nanotubes to lung abnormalities in exposed
rats, while noting their ability to penetrate cells.

According to Jim Thomas in The Ecologist (Feb.
2004), the Food and Drug Administration and other agencies are
‘privately admitting they have made a mistake in letting
nanoproducts onto the market without safety studies, and are
looking for ways to tweak existing regulations.’ Thomas, whose
Nanowatch column appears in the London-based magazine, is the
European program manager for the Action Group on Erosion,
Technology and Concentration, or ETC Group. A 2003 communiqu?
posted by the Winnipeg-based ETC Group (www
highlights the central problem with the current push to
commercialize nanotech. Many companies have dismissed the idea that
particles approved for commercial use at much larger sizes ought to
be retested in their nano form, the watchdog group notes. That’s
ironic, given that ‘the impetus for their development stemmed from
the radical changes that can happen when a substance is reduced to
the nano scale.’

Although billions of U.S. federal dollars are now slated for
nanotech research and development, only about 11 percent of that
money is earmarked this year for health and environmental studies.
Some of the studies will take years to complete; others could yield
results more quickly. While the call for more research is spreading
along with concern, there are currently no specific regulations to
control the release of products containing nanoparticles in any
country — and no labeling requirements either. With the widespread
use of nanotechnology now looming in agriculture, medicine, and
other crucial fields, critics call it another example of an
industry moving ahead without fully investigating potential
long-term consequences.

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