As the use of nanotechnology expands as a component of manufacturing, researchers are taking a harder look at how the tiny particles may affect human health. In particular, they are studying the similarities between the effects of inhaling nanotubes and nanofibers and microscopic asbestos fibers. Exposure to asbestos is linked to the development of asbestosis, a severe scarring of the lungs, and mesothelioma, a deadly form of cancer.
Nanotubes are tiny, cylindrical carbon molecules that exhibit extraordinary strength and unique electrical properties, and are efficient conductors of heat. The National Nanotechnology Initiative (NNI) says nanotechnologies are estimated to have impacted $251 billion across the global economy in 2009, and this number is estimated to grow to $2.4 trillion by 2015.
The NNI is a U.S. government research and development (R&D) initiative that coordinates funding for nanotechnology among federal departments and agencies. Funding support for nanotechnology R&D stems directly from NNI member agencies.
Nanotechnology is used in manufacturing, in a variety of commercial products and processes. Nanomaterials – usually defined as carbon nanotubes (CNT) and carbon nanofibers (CNF) – are used to manufacture strong but lightweight materials. They are used in such products as boat hulls, sporting equipment like bicycles and tennis rackets, and automotive parts.
Beasley Allen attorney Mike Andrews has been working with victims of asbestos exposure for many years, and expressed concern about the similar nature of nanotechnology in 2008. In particular, he examined cases where high-end bicycle handlebars were constructed with carbon fiber nanotubes. When the handlebars are cut by customers with a saw to create a custom fit, the tiny nanoparticles are released, where they can be inhaled.
“If our work in asbestos litigation has shown us anything, it is that companies with knowledge of hazardous products often withhold that knowledge from the public,” Andrews said. “I strongly suspect that carbonfiber-based nanotechnology will be no different, and that as these products become more prevalent in the marketplace we will learn that they can be dangerous and deadly if inhaled.”
The NNI estimates more than 800 household products rely on nanomaterials and nanotechnology. These include computer processors; stain- and odor-resistant and wrinkle-free clothing, and antibiotic bandages. Nanomaterials are even used in sunscreens and cosmetics. The NNI estimates more than 15 percent of all products will contain some form of nanotechnology by 2015.
Researchers believe that, similar to asbestos, nanoparticles are not necessarily harmful in and of themselves, in materials and products in which they are safely encased. However, they are concerned about nanotube fibers being released when those products are broken or incinerated, and they are concerned about workplace safety for those who work with nanofibers and nanotubes.
In 2008, the Washington Post reported that “preliminary evidence of cancer risk is strong enough to justify urgent follow-up tests and government guidance for nano factory workers.”
At that time, the National Institute for Occupational Safety and Health (NIOSH), had begun conducting nanotechnology research, and recommended that people working with carbon nanotubes follow certain guidelines for working with engineered nanomaterials. This included using respirators and special filters to clean the air.
Law 360, in a report about nanotechnology and the role of insurers, noted that as of April 2013 NIOSH was not aware of any reports of adverse health effects in workers producing or using CNT or CNF. However, NIOSH did publish findings from recent animal studies, which indicated animals exhibited “adverse lung effects at relatively low-mass doses of CNT and CNF, including pulmonary inflammation and rapidly developing persistent fibrosis” – in other words, extremely similar to symptoms of asbestosis and/or mesothelioma.
As a result of its findings in the animal studies, NIOSH issued recommended exposure limits (REL) for nanomaterials not to exceed 1 microgram per cubic meter of air, which is the lowest airborne concentration that can be accurately measured.
Also in April 2013, the U.S. Department of Labor’s Occupational Safety and Health Administration (OSHA) published a fact sheet titled “Working Safely with Nanomaterial.” The agency stopped short of declaring any mandatory Permissible Exposure Limit (PEL) for nanoparticles, but did issue a recommendation that worker exposure to CNT and CNF not exceed 1.0 micrograms per cubic meter as an 8-hour time-weighted average, which it based on the NIOSH REL.
Law 360 author Lindsey A. Davis, of Zelle Hofmann Voebel & Mason LLP, speculates that “NIOSH’s 150-page Current Intelligence Bulletin 65 and OSHA Fact Sheet 3634 may arm employees with ammunition to claim that employers have been put on notice about the potential occupational health and safety risks associated with CNT and CNF and the recommended occupational exposure limits to such nanomaterials.”
In its risk assessment of nanotechnology, the NNI admits, “Exposure to nanomaterials may occur unintentionally in the environment or through use of nanotechnology-enabled products. … Biological or environmental systems may be exposed to these dispersed engineered nanomaterials and respond through systems and pathways designed to buffer exposures to substances that could perturb human health or adversely impact the environment.”