By David Funkhouser
A new study has found sunlight may help break down carbon nanotubes—but also suggests the products of the photochemical reaction could be toxic to aquatic organisms.
“This study is one of the first to address whether [carbon nanotubes] undergo reactions in the environment,” said environmental engineer Chad Jafvert of Purdue University, one of the researchers. He said exposure to sunlight seems to produce highly reactive oxygen molecules that could degrade the carbon nanotubes; but those same molecules also are known to damage cells and DNA.
The results mirror the complexity of the effort to understand how manufactured nanoparticles—materials measured in billionths of a meter—might affect the environment and human health.
The growing use of nanomaterials in hundreds of industrial and consumer products, and their huge potential in medicine, electronics, energy and other fields, have lent urgency to that effort. Scientists are concerned about what happens to these substances when workers and consumers are exposed to them, and when they enter the environment.
Because of their tiny size, the materials can take on extraordinary properties. Carbon nanotubes, for instance, can be lighter and stronger than steel and are already used to make bicycles, tennis racquets, car bumpers and other products.