January 17, 2010
This week I spent two days in Columbia, South Carolina where I was attending a meeting of the USC NanoCenter External Advisory Board. If you surf the web looking for connections between nanotechnology and food, you will turn up some documents that describe new products and other pages that describe nanotechnology as “the new threat to food” or “biotech on steroids”. Should you be worried?
The short answer to that question is “Probably not.” A longer answer would bust the word limit I’ve set for myself on the Thornapple blog, especially if we move beyond food and consider cosmetics, too. But let me make just a few observations that web surfers would be unlikely to turn up in the top twenty to thirty hits they might get from typing ‘nanotechnology’ and ‘food’ into Google.
First, recognize that the word ‘nanotechnology’ covers an extraordinarily broad range of tools and techniques. Most of them have nothing directly to do with food. Succinctly, any tool or technique that exploits properties of matter that emerge at the nanoscale (between 100 billionths of a meter and 2 billionths of a meter) can be called nanotechnology. The biggest buzz surrounds ‘engineered nanoparticles’ which are made from manipulating the chemical bonds that hook atoms and molecules together. ‘Carbon nanotubes’, for example, have extraordinary strength, and conduct electricity with great efficiency.
Some carbon nanotubes have been shown to have toxic effects in fish. The studies on the toxicity and environmental fate of engineered nanoparticles are in their infancy, yet there are indeed manufacturers that are developing and selling products that use them. If you are inclined toward environmental activism against toxics, this might indeed be something you should be worried about.
However, no one is proposing to deliberately put carbon nanotubes in food. What is being proposed is that nanoscale particles of natural substances be used both in foods and in food packaging, as well as in other consumer products. Nano-sized particles of Vitamin E, for example, will have much greater uptake by the body. Nano-thin layers of clay can be incorporated into food packaging to improve biodegradability. Nano-thin capsules can surround vitamins or flavors, releasing them when you chew (and preventing them from degrading before you chew). Other nanotechnologies may be used in food or farming, but will not actually be in or near food. Nano-filters will be more effective at removing pollutants from water supplies.
Questions can be raised about any of these food nanotechnologies, and they should be raised. But these questions are of a different order than the questions that should be raised about non-food nanotechnology that is entering the environment. The former questions are (unlike the later) questions that food scientists and regulators know how to answer. There is still room for activism, because the anti-regulatory mentality in our political culture can get out of hand. But the nature of the uncertainties and risks is totally different.
I stress this point because some of the more hair-raising stuff on web makes this distinction very difficult to draw. Some of the studies on toxicity from nanotubes are cited, then without skipping a beat, the authors go right to a discussion of techniques for encapsulating flavors in nanothin fat globules. But encapsulation is not new in the food world. Think “Melts in your mouth, not in your hand.” So for those of you inclined to familiarize yourselves with the gory details, I say “Surf away.” But if this blog is the only thing you ever plan to read on nano food, save your concern for the risks that clearly matter, and recognize that not everything that gets called nanotechnology qualifies.
It’s unlikely that any nanotechnology will be used in getting next year’s share of fruits and vegetables to Thornapple members, but someday, who knows? I can’t imagine us trending toward encapsulated flavor or vitamin supplements, but there are other things waiting in the wings. Readers that have been out to the farm know that we grow in hoop-houses—greenhouses that are made from metal hoops covered with plastic. That plastic eventually goes into the environment, and I can imagine nanotechnologies that improve its ability to let in light as well as its degradability after we are done with it. Debates on the compatibility of nanotechnology and the organic standard are just beginning, and my view is that we should evaluate proposals on a case-by-case basis, rather that adopting a blanket approach that could rule out some environmental winners.
But that’s my word limit, so shut me up and go cook some chili!
Paul B. Thompson was the Lead Investigator for a National Science Foundation Grant to explore social and ethical implications of nanotechnology in agriculture and food.