Portland, Ore. Nanotechnologists have performed theoretical calculations predicting that buckyballs, a common nanoparticle, could disrupt the functioning of deoxyribonucleic acid (DNA).
These 60-atom hollow spheres of carbon can be functionalized for a variety of applications from ultrasmall sensors to drug dispensers targeting particular sites inside the body. Buckyballs are developed for a wide variety of applications, including dry lubricants and semiconductors.
The bad news is that computer simulations performed by Vanderbilt University and Oak Ridge National Laboratories researchers show that buckyballs have a strong affinity for animal DNA, attaching to it in a manner that prevents it from performing the reproductive actions necessary for cells to mount immune-system responses or even to repair themselves.
Such an outcome represents "a serious potential health hazard," said Vanderbilt University engineering professor Peter Cummings, who performed the simulation with former graduate student Alberto Striolo, who is now a professor at the University of Oklahoma, and post-doctoral research scientist Xiongce Zhao at Oak Ridge National Laboratory.
Today, buckyballs are already treated like a hazardous material simply because their toxicity is unknown, said Cummings. So these calculations come at just the right time, he said, when researchers can study just how toxic buckyballs and other nanoparticles may or may not be before they are mass-produced.
"People are not exposed to buckyballs yet, because today they are made in such small amounts measured in grams per year. And their use is pretty much restricted to research labs," said Cummings. "As far as I know, there are no commercial applications that use buckyballs yet, but. . . a lot of people are doing research trying to find ways of functionalizing buckyballs and other nanoscale building blocks by attaching molecules to them for specific applications in bioelectronics and elsewhere. What we want to know now is: Which of the nanoscale building blocks have an affinity for living tissue, and if they do, where will they end up in our bodies?"
Instead of performing experiments in the lab, however, Cummings has joined the ranks of engineers using computer simulations so detailed that the results of laboratory tests and elaborate procedures can be accurately performed by the model without researchers ever having to dirty a petri dish.
"I hung up my lab coat years ago in favor of computer simulations," said Cummings. His team used the same kind of software algorithms that engineers use to create models of new materials or designers use to discover new drugs.
The team's report follows one last month in which aluminum oxide nanoparticles in the water supply of plants corn, cucumbers, cabbage, carrots and soybeans was experimentally verified to stunt growth (see www.eetimes.com/showArticle.jhtml?articleID=174403325).
Even worse, last year professor Eva Oberdorster of Southern Methodist University reported experimental evidence that the presence of buckyballs in water killed water fleas and damaged the brains of fish. Concentrations of buckyballs that picked up from water through their gills were found in the tissues of the fish's brains, leading to a 17-fold increase in brain damage. At that time, Oberdorster advised a moratorium on the manufacture of nanoparticles until scientists had time to study how fish will be affected by them, and how the bodies of filter-feeding organisms, such as mollusks and zooplankton, will regulate the intake and distribution of these nanoparticles.