Science fiction might have us believe that tiny particles seeping into soil and altering plant DNA will lead to the rise of giant killer tomatoes. But a new study suggests that exposure to certain nanoparticles may in fact have a shriveling effect on some plants.
Researchers with the National Institute of Standards and Technology and the University of Massachusetts, Amherst have documented the first findings that engineered nanoparticles can enter plant cells and damage their DNA.
In laboratory experiments, researchers led by Bryant C. Nelson, a NIST biochemist, tested copper oxide nanoparticles ranging in size from one nanometer to 100 nanometers. For comparison, the head of a pin measures about one million nanometers across, and a human hair is generally around 60,000 nanometers in diameter. As controls, the scientists also tested larger copper oxide particles and copper ions.
They found that exposure to nano-scale copper oxide particles stunted the shoots and roots of radishes and two species of rye grass. Plants exposed to the highest concentrations of these nanoparticles, which are commonly used as industrial catalysts, were the most severely stunted. And radishes took up significantly more copper from the nanoparticles than from larger copper oxide particles.