Nanoparticles Cause Brain Injury in Fish

By Robert J. Korpella

First posted on 09-21-2011

Nanoparticles are ultrafine; present almost at the molecular level. While often considered a modern science, the use of nanoparticles can be traced back to the 9th century when artisans used the optical properties of these particles to produce a lustrous sheen on pottery pieces.

Today, nanoparticles are used to create product mainstays like stain-resistant clothing, clear sunscreen and tennis balls that keep their bounce longer. Scientists at the University of Plymouth recently discovered a darker side to nanoparticles: a potentially detrimental effect on the brain and central nervous system.

Professor Richard Handy and a team of researchers subjected rainbow trout to titanium oxide, a whitening agent found in paints, toothpaste, detergents and other applications. Titanium oxide is also being considered for food industry projects.

The scientists discovered that ingestion of these particles resulted in holes, or vacuoles, in the trout’s brain. In addition, the particles caused nerve cells in the brain to die. This study marked the first time these effects were observed in live vertebrates.

Handy explained that the research had not yet yielded whether the effects were the result of nanoparticles entering the brain, or if they were the result of a secondary chemical or reactive effect.

“It is worrying that the effects on the fish brain caused by these nanoparticles have some parallels with other substances like mercury poisoning, and one concern is that the materials may bioaccumulate and present a progressive or persistent hazard to wildlife and to humans,” Hady said.

Handy hopes that the results of his work will influence policymakers discussing environmental protection and human safety with respect to nanomaterials.