Source: The Chronicle of Higher Education September 10, 2004, Title: “The Dark Side of Small,” Author: Richard Monastersky
Faculty Evaluator: Scott Gordon, Ph. D., Jennifer Lillig Whiles, Ph. D.
Student Researcher: Jason Piepmeier
The science of nanotechnology is rapidly advancing, but there is little research to show whether or not nano-sized molecules are safe for people and the environment.
Nanotechnology is the science of using molecules that are virtually impossible to see; one blood cell measures at 7,000 nanometers in width. Nanotechnology has virtually unlimited potential. Products such as stainless, wrinkle free pants use nanotechnology as well as transparent sunscreens and tennis balls that keep their bounce. The U.S. government spent close to $1 billion in 2004 on research and development in nanotechnology.
However, only 1 percent of it is going towards research for risk assessment, despite the fact that nanotechnology also has the potential to cause harm to people and the environment. The nano-sized molecules can damage, or kill, the skin cells of humans and also kill valuable bacteria in water. The reason little money is given to research the risks is nanotechnology’s huge upside; some estimates predict that the nanotech market will reach $1 trillion in a decade.
Thousands of papers have come out touting different developments in nanoscience, but fewer than fifty have examined how engineered nanoparticles will affect people and the environment. The studies that have been conducted to determine if nano-molecules are safe paint a grim picture for nanotechnology. In the spring of 2004, Eva Oberdorster, an adjunct scientist at Duke University, made headlines with potentially disturbing news about highly praised a nanoparticle called “fullerness,” named for the inventor R. Buckminister Fuller.
The “fullerness” is made of 60 carbon atoms, bonded together like a molecular soccer ball. Oberdorster put a solution of “fullerness” into a tank with large-mouthed bass and later examined different organs in the fish. She found signs of oxidative damage in their brains and speculated that the nanoparticles had stimulated the production of free radicals, highly reactive compounds that can cause cellular damage. “Normally,” she said, “particles can’t get into the brains of fish or people because a protective structure called the blood-brain barrier keeps out harmful materials.” But Oberdorster’s, and other experiments show that nano-size particles can slip through that barrier by traveling up nerve cells into the brain.
Oberdorster’s father also studies the effects of nanoparticles. Dr. Gunter Oberdorster, a professor of toxicology in environmental medicine at the University of Rochester, received a $5.5 million, five-year grant from the Department of Defense to study the effects of nanoparticles. Scientists at the University of Rochester looked at the titanium dioxide nanoparticles that are used as pigments in white paint. Rats and mice inhaled particles ranging in size from 12 nanometers up to 250 nanometers. The smaller particles were found to cause more inflammation than an equal amount of larger particles. “The smaller particles react differently from the larger ones,” he says, “because nano-size materials evade the normal defense system in the lungs, the macrophage cells that gobble up the irritants and clear them out.” Once nanoparticles get deep into the lungs, they can cross over into the blood stream and from there can into any organ in the body. Inhaling the nano-sized particles in titanium dioxide, which is on the market now, is unlikely because they are captured in liquid substances. However, Dr. Oberdoester suggests that it may be possible for nanoparticles to cross over through the skin.
Another study, run by Anna A. Shevedova, an adjunct associate professor at West Virginia and a senior staff scientist at the National Institute for Occupational Safety and Health (NIOSH), found that carbon nanotubes generated dangerous free radicals in cultures of human skin cells. Her research team reported that the nanotubes caused oxidative damage that triggered the deaths of cells.
Almost everybody involved in nanotechnology says it is too soon to tell whether and how these materials might harm people or the environment. But early studies show that this is something that should be looked into more seriously. In a survey conducted by North Carolina State University, public perception of nanotechnology remains fairly positive. As has happened with new technologies in the past, this optimism may become accusations and lawsuits if the side effects of nanotechnology outweigh the benefits.