Facing the Dangers of Nanotech

bethr writes "Technology Review has a Q&A with Andrew Maynard, the science advisor for the Woodrow Wilson International Center's nanotechnology project regarding the dangers of nanomaterials and why we have to act now." From the article: "Individual experiments have indicated that if you develop materials with a nanostructure, they do behave differently in the body and in the environment. We know from animal studies that very, very fine particles, particles with high surface area, lead to a greater inflammatory response than the same amount of larger particles. We also know that they can enter the lining of the lungs and get through to the blood and enter other organs. There is some evidence that nanoparticles can move into the brain along the olfactory nerve, so this is completely circumventing the blood-brain barrier."

Re:Nanomaterial == molecules

[Anonymous Coward]

Since assembly-based nano isn't anywhere near yet, whenever news articles use the term 'nano', what they really mean is something more like 'chemical' or 'molecular'.

No, they mean really-finely-ground-up-stuff, that's a lot bigger and more complex than the sort of thing (oxygen molecules or glucose) that normally crosses the blood-brain barrier.

Re:Michael Crichton's Book

[mblase]

This is very erie... Anyone read Prey by Michael Crichton?

Yeah, it was replete with pseudoscience that would make a great movie, but terrible research. Nanobots that are as intelligent, sophisticated, and above all mobile as the ones in that story aren't just impossible under current technology limits, they're impossible at all.

Sixty years ago, tech enthusiasts were absolutely certain we'd have a colony base on the Moon by now. Sixty years from now, nanotech will be just as stunted compared to where we imagine we'll be.

One Man's Assertions...

[clang_jangle]

...doth not an article make. Won't someone PLEASE think of the *science* ?!

Re:Scale matters, and so does hype

[radtea]

I'm old enough to remember something very similar to this back when gene splicing first became practical. Recombinant technology had a lot of hype around its promise, while at the same time there was an equal amount of hype about its dangers.

There was actually a voluntary suspension of recombinant DNA research for a short time back in the '70's. Everyone started doing it again when the truth became clear: recombination happens in nature all the time, and the mechanism was such that naturally occuring recombination was doing all the things that scientists wanted to do. Given this, it was felt there was little risk of uncontrolled side-effects. It is worth adding that this is different from believing that there is little risk (social, economic or environmental) from GMOs specifically designed to cause harm to others for the profit of some, like those containing Monsanto's Terminator gene.

The situation with nanoparticles is a little more ambiguous. There was as story on /. today on carbon nanotubes in ancient steel, and of course the first discovery of exotic carbon allotropes was in smoke, which is not exactly a rare substance. This suggests that some forms of nanoparticles have been around in the environment for a long time. However, it does not follow from this that naturally occuring nanoparticles are similar to the ones we are trying to create. Some, like carbon nanotubes and buckyballs, are unlikely to cause harm. But given their ability to infiltrate the body's natural defenses there needs at least to be careful assessment of new nanosubstances before any are allowed to released into the environment.

Nano-materials are nothing more than large molecules, after all, and you wouldn't want people releasing large amounts of potentially deadly substances into the environment in the fond hope that they won't harm anyone with sufficient money to sue.

Re:Scale matters

[bradbury]

Generally speaking you have to be very careful about the precise material as well as its size. Iron and copper ions for example can be very toxic due to their ability to contribute to the production of free radicals (which will damage proteins and DNA). Zinc ions on the other hand are essential and play important roles in the structure of all zinc finger regulatory proteins. Organisms have protein systems that control the transport and storage of iron and copper ions to a much greater extent than zinc ions.

Now it seems likely that metal oxides, being noncharged, are less likely to be involved in chemical reactions (its usually very hard to get oxides to interact at all). So I would expect zinc oxide (in contrast to iron particles) to be relatively benign. The question becomes whether the body has effective mechanisms for binding to and either degrading or removing nanoparticles. If it does not then exposure is potentially cumulative and may be harmful. The normal reaction of the body to something it cannot degrade or remove is to form a granuloma (a collection of cells designed to isolate the problem) surrounding it. So depending on the precise size of the particles they might either penetrate cell membranes and accumulate within cells (which is probably not good) or potentially accumulate until the point where granulomas may form. On the skin surface that isn't bad since you are sheding the skin anyway. Within the lungs however it can be a much larger problem (as silicosis and black lung disease show).

Nanoparticles are not new -- coal miners, blacksmiths and cooks have been dealing with them for centuries. What may be new is greater exposure to a larger variety of nanoparticles by a greater fraction of the population. That is worth being careful about but does not translate into throwing out the baby with the bathwater.

nano

[H0D_G]

as a student in a nanotech degree, I have to laugh at the conjectures here. all of these comments about "grey goo" and self replicating "nanites" are pure alarmism. Drexler himself doesn't believe it's possible. and as for all of this screaming about the control of nanomaterials, powder technologies are only a very small part of the whole nanotech research area. most of the research that I've come in to contact with has been focused not on powders but on surfaces and coatings, or biomedical sources, which is where all the money is and Prey is horribly bad. the situation described, as well as many of the properties attributed to nanomachines, is complete fiction. problem is, it's believeable to non-scientists. when talking about nanotechnolgy to non-scientists, I either get "what is that" or "you'll kill us all, grey goo." it's actually a damaging book, in that it actively attempts to hobble a science before it was anywhere near that level of complexity.