Carbon nanotubes are a type of microscopic nanomaterial that is quickly gaining prominence in consumer product and industrial industries. Among experts, however, they are better known as “the next asbestos.” Until now, researchers lacked sufficient evidence to prove that carbon nanotubes were linked to cancer. But in a recent study comparing nanotubes and asbestos, researchers found much stronger evidence of the material’s carcinogenic effects.
The U.K. study, published earlier this month, examined how long, thin, carbon nanotubes (also known as CNT) affect mice. While past studies injected CNT into the abdominal cavity, this study placed the material directly into the pleura (the thin lining around the lungs). This is where mesothelioma – a deadly cancer caused exclusively by asbestos – is found in humans. There, like asbestos fibers, the CNT caused long-term inflammation that led to tumors.
“Long, thin nanotubes have a very similar structure to asbestos,” said Anne Willis, director of the Medical Research Council (MRC) Toxicology Unit in Leicester, England, and the study’s co-author. “The immune system does a good job of recognizing shorter, thicker, or tangled up nanotubes.”
But such alternatives have escaped the attention of manufacturers. Already a multibillion-dollar industry in North America in Europe, CNT is projected to grow more popular through 2020. What can people expect as a result?
CNT an All-Too-Familiar Concern
Carbon nanotubes are tiny, hollow tubes made of carbon atoms. Though 10,000 times smaller than human hair, they are 100 times stronger than steel. This makes the fibrous nanomaterial ideal for manufacturing strong but lightweight products such as sports equipment, aircrafts, automobiles, and electronics.
Asbestos, too, is a durable, fibrous material invisible to the naked eye. It’s this quality that makes asbestos and materials like asbestos so useful for product manufacturers. But, while they might prove useful in manufacturing, they are incredibly dangerous to our bodies.
Many manufacturers used asbestos to reinforce products and buildings before the 1970s when the Environmental Protection Agency (EPA) and the Occupational Safety and Health Administration (OSHA) linked asbestos exposure to cancer. Researchers found that asbestos cannot be broken down by the body, and, similarly, teams researching CNT found similar results.
Disturbingly, CNT plays a big role in healthcare. Body implants, medical devices, and dental fillings containing these nanofibers have stormed the biomedical industry, and researchers believe CNT could even diagnose cancers. Its potential to cause cancer is a concern we still know very little about.
Let’s Hope History Doesn’t Repeat Itself…
Focused on its benefits, manufacturers see CNT as the promising new technology of the future. Asbestos, too, was once put on the same pedestal. When first discovered, the mineral was labeled a “miracle fiber” for its strength and commercial value.
This made asbestos-related companies reluctant to reveal its dangers to the public. For decades, they put profits before the safety of their workers, who now suffer (or have already died) from chronic and lethal diseases. Even before asbestos-caused mesothelioma rates decrease, we can only wonder whether a nanotube-caused epidemic awaits.
What we do know, as of now, is another distinction between asbestos and CNT that could make all the difference to consumers’ health: exposure. Mesothelioma stemmed from uncontrolled exposure to asbestos. When a material is found hazardous to humans, manufacturers and regulators must control exposure to ensure safe use – or to mitigate or stop production altogether.
Public health must always come first.
“We want our research to inform manufacturers and regulators about safer options … when a nanofiber is being selected for the production of nanomaterials for emerging technologies,” Willis said.
Marion MacFarlane, the study’s lead author, said: “This research could help us define key indicators for early detection [of mesothelioma] as well as provide information for developing targeted therapies for this devastating disease.”