Buckyball Causes Brain Damage in Fish

ANAHEIM, Calif., March 29 -- Researchers have found that a type of Buckyball -- a carbon nanoparticle that shows promise for electronic, commercial and pharmaceutical uses -- can cause significant brain damage in fish. The small preliminary study, the first to demonstrate that nanoparticles can cause toxic effects in an aquatic species, could point to potential risks in people exposed to the particles, they said. The study was described yesterday at the 227th national meeting of the American Chemical Society.

"There are many potential benefits of nanotechnology, but its hazards and risks are poorly understood. This study gives us additional cause for concern," said study leader Eva Oberdorster, PhD, an environmental toxicologist with Southern Methodist University in Dallas.

Buckyballs are pure carbon structures shaped like soccer balls that differ from other forms of pure carbon, like diamond and graphite, in the way their atoms are bonded. The structures, also known as fullerenes, are thousands of times smaller than the width of a human hair. Experts predict the widespread use of these and other nanoparticles in the future. Buckyballs show promise as components of fuel cells, drug delivery systems and cosmetics that delay aging.

In a controlled laboratory study, the researcher exposed nine juvenile largemouth bass -- confined to 10-liter aquaria -- to a form of water-soluble Buckyball (C60) at a dose of 0.5 parts per million. After 48 hours, the animals developed significant brain damage as measured by lipid peroxidation, or the breakdown of lipids, as shown by laboratory analysis of brain tissue samples. The brain damage seen in the fish exposed to the nanoparticles was severe: 17 times higher than that seen in nine unexposed animals, Oberdorster said.

To date, there have been no human studies of the health effect of Buckyballs or other manufactured nanoparticles, she said.

Oberdorster is planning additional studies in the future to determine the mechanisms of action and to find out how many Buckyballs get into the fish's body and where the particles are distributed. She expressed concern that nanoparticles could begin to accumulate throughout the food chain, affecting not just fish, but other animals, plants and possibly people.

Researchers worldwide are just beginning to test manufactured nanoparticles for signs of possible toxicity, but it may be years before any reliable human data are available, Oberdorster stressed. As several companies are beginning to manufacture engineered fullerenes, an initial concern is workplace exposure to the particles, she said. This study suggests that an evaluation of human exposure levels should be completed before these particles are widely used in consumer products, she said.

For more information, visit: www.acs.org