Vicki Colvin

---

Position: Director, The Center for Biological and Environmental Nanotechnology at Rice University

---

Issue: The safety of nanotechnology. Do breakthroughs in nanotechnology-widely hailed for their potential in biomedicine and materials science-present unique health and environmental dangers that need to be studied?

---

Personal Point of Impact: Colvin's nanochemistry group, which makes new kinds of nanoparticles, is beginning to work with toxicologists, biologists, and bioengineers to evaluate the unintended biological effects of these materials.

---

Technology Review: Questions about the safety of nanotechnology suddenly seem to be everywhere, from Michael Crichton's bestselling novel Prey to calls for a moratorium on the technology by at least one environmental group. What are the chief concerns?
Vicki Colvin: Nanomaterials are different. Because of their small size, we are able to get them into parts of the body where typical inorganic materials can't go because they're too big. There is an enormous advantage to using nanoparticles if you're engineering, for example, drug delivery systems or cancer therapeutics. This would suggest that nanomaterials that are unintentionally introduced into the body may also undergo similar processes. The concern-or the hypothesis would be a better way to say it-is that nanomaterials differ in their reactivity and biological availability. You can't help but ask, Well, if they are powerful biological actors, then what about unintentional consequences?

TR:Are the dangers of nanomaterials well understood?
Colvin: It's not as if no one has ever thought about how particulate matter generally can interact with organisms. We can learn a lot from particle toxicologists who characterize the effects of aerosolized particles of all sizes on health, as well as from bioengineers who consider the effects of larger particulates generated by implants wearing down in the body. Still, specific information on the health impacts of very small, nanoengineered particles under 20 nanometers is hard to come by. So the one thing everybody agrees on is that there just is not a lot of information out there.

Getting that information isn't going to be a simple task. Nanomaterials are incredibly diverse. You can have nanoscale carbon, nanoscale Teflon, nanoscale you name it. Within that huge diversity of materials, it would be almost amazing if all those materials were as safe as water. The toxicology data is going to start to come out, and it is almost certain that it's not going to be: nanomaterials are totally safe. Nothing in the world is totally safe.