Sunday, March 28, 2004

Nano is a concept by which we measure our pain

Toxicologist Eva Oberdorster's new study on the effects of nanoparticles on aquatic animals deserves some thoughtful analysis, yet the Washington Post makes some strange leaps of logic in its reporting.

    The study, described at a scientific meeting Sunday, was small and has yet to be peer reviewed or published in a scientific journal. And although some companies anticipate making tons of the particles within the next few years, current production levels are relatively low, so the risk of exposure for humans and other animals is still quite small.

    Nonetheless, the findings underscore the growing recognition that the hot new field of nanotechnology, which federal officials have said will be at the heart of America's "next industrial revolution," may bring with it a number of old-fashioned trade-offs in terms of potential environmental damage and health risks.

    Other animal studies have already suggested that a related class of nanoparticles cause lung injuries when inhaled, raising concerns about worker safety in the small but growing number of nanoparticle factories.

Sorry, but the qualifiers "may" and "suggested" just do not do enough to counteract the impression left on the reader that nanoparticles cause lung injuries and threaten factory workers.

As I've pointed out before, the "animal studies" mentioned above concluded that if you pump rats' lungs full of nanotubes, they will suffocate. The toxicity of the nanoparticles was not conclusive and, in fact, it was suggested that the clumping was a good sign, since it prevented the nanotubes from reaching deeper into the lungs.

The vague idea of some future "factory workers" being endangered is mentioned once, then dropped.

While it would be foolish for nanotech businesses and advocates in government to dismiss concerns over "nanotox," all parties need to stick to the evidence as it's presented. This latest study is yet another small piece of evidence in a longer process of scientific discovery. Despite the tendency of the media to want to tell its readers what these small-scale studies mean by making all sorts of unscientific leaps in logic for them, don't lose sight of what is actually being presented.

Some better context can be found in The New York Times' coverage:

    "This is a yellow light, not a red one," Dr. Oberdorster said in a telephone interview last week.

    Vicki L. Colvin, whose laboratory at Rice University's Center for Biological and Environmental Nanotechnology supplied the buckyballs used by Dr. Oberdorster, was even more cautious about the results, which have not yet been reviewed by other scientists.

    Dr. Colvin said that the surface characteristics of the lab's buckyballs, which are not a form that is commercially available, needed further study. She said that they had not been coated, a process that is commonly used to limit the toxicity of such materials in applications like drug delivery.

Nanotechnology is such a young discipline that any issue for which the nano name is invoked is largely a reflection of a personal world view or political agenda rather than any overwhelming body of evidence. Nanotechnology advocates in business and government choose to focus on the optimistic leaps of logic, while those who see corporate conspiracies in the wallpaper can make just as many plausible or implausible leaps into the negative. As I told Neofiles a few months ago:

    A health advocate could say that once nanoparticles breach the blood-brain barrier, we're entering into dangerous territory, while another can say that breaching that barrier will enable a range of cures for various brain disorders. Nanotechnology, right now, is an unsettled wilderness that is either abundant with resources for the picking, or a vast frozen wasteland. It's a reflection of your own world view.

Right now, the general public is being bombarded with some amazing predictions of how nanotechnology will completely alter almost every aspect of their lives. To many, the claims seem not only fantastic, but implausible. Nanotech proponents in government and business are just as guilty of promoting selective logic as the neoluddites of the environmental movement when they ask the public to believe positive implausible scenarios and not to pay attention to the negative.

It's a difficult concept to describe. I was asked by a reporter for NPR's "Marketplace" last week to define nanotechnology. I gave the usual explanation (under-100-nanometers, special-properties, etc.), and then I struggled to explain how nanotechnology right now is more of a concept than anything else. We've created the building blocks and dumped them on the floor. What we create with them now, and how safely we do it, is yet to be determined.

So, there is nano the science and nano the business, and they're moving along quite nicely as they take their baby steps. But when it reaches level of public debate, nano often loses its solidity to become neither science nor business, but a concept that is a reflection of the human imagination.

Related Posts
Nanotubes and the tale of the rats
The nano-brain barrier
New materials are not without risk


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