Abstract
To grow safely, nanotechnology needs time and space.
When we sat down to write Nanotechnology: A Gentle Introduction to the Next Big Idea in 2001, the definition of nanotechnology was still up for grabs. Some scientists and futurists envisioned nanotechnology as a world of “molecular assemblers,” or engines that could build macroscale devices from atomic or molecular components one particle at a time. Factories of these assemblers would be able to make anything without waste or overhead cost, they argued, and do it all with perfect precision. Others, including Mikhail Roco, the first director of the National Nanotechnology Initiative, thought of the emerging discipline in a broader light.
In 2001, Roco presented what has since become a generally accepted definition: “[Nanotechnology] refers to the fundamental understanding and the resulting technological advances arising from the exploitation of new physical, chemical, and biological properties of systems that are intermediate in size, between isolated atoms and molecules and bulk materials.” This approach places nanotechnology at the convergence of physics, chemistry, biology, and engineering. It indicates that there is something special about the nanoscale–that with nanotechnology, it isn't about making things small because smaller is better (as with Moore's Law) but about how nanoscale systems behave in fundamentally different ways from their larger cousins. They sit between the macroscale physics of Newton and the quantum physics of Schrödinger and can have the properties of either or both mixed together. For example, their color sometimes changes with size (the quantum size effect), and they can have electronic properties that differ from commonly accepted principles such as Ohm's Law. At a size comparable to DNA, proteins, and photosynthetic centers, these systems also exhibit some of the same properties as basic biosystems.
The benefits of this type of engineering are enormous. Yet, the suggested presence of “molecular assemblers” within the range of nanotech possibilities sparked scares. What if factories of these assemblers were to work in concert and develop a form of intelligence? And what if this intelligence could scale arbitrarily, take any form, and manipulate matter any way it wanted to? Could this be the most dangerous thing humans ever invented? Could it be the next stage in our own evolution? Could it destroy us?
Scientists, perhaps most notably Nobel laureate and nanotech pioneer Richard Smalley, looked at these possibilities and concluded that for various fundamental reasons, the construction of a general-purpose molecular assembler is impossible. Even Eric Drexler [see next page], the first proponent of molecular assemblers, distanced himself from the idea, focusing instead on special-purpose assemblers that would not require the complexity of their general-purpose cousins. With the disappearance of general-purpose molecular assemblers from mainstream scientific discussion, concerns about apocalyptic corollaries faded, but the nature of nanotechnology as currently defined could still pose risks.
If nanoparticles are the same size as biological entities such as proteins, could they be absorbed into tissues and cells in potentially hazardous ways? If nanoparticles prove to be toxic, could their release into the atmosphere cause an environmental catastrophe such as that caused by asbestos, chlorofluorocarbons, or DDT? And don't the very properties that make them interesting–the fact that, at the nanoscale, particles can behave fundamentally differently than particles of the same composition at the macroscale–mean that current regulatory processes and safety codes are ill-prepared to deal with them? In response to such concerns, some activist groups have called for a moratorium on nanotech research, even though such a ban would inhibit gathering the very data that would allow for the informed decisions these groups are demanding.
And therein lies the additional challenge. Nanotechnology is not a device; it is a set of ideas, principles, tools, and approaches. For this reason, it has been described as a sort of second Industrial Revolution. Like the first Industrial Revolution, there is enough commonality in nanotechnology to make looking at it holistically a useful exercise, but it is also true that each application needs to be examined independently.
Advances in nanotechnology show great promise as a way to develop drugs, diagnostic tools, and therapeutic treatments for intractable diseases such as cancer. Most of this potential comes from nanoscale particles' ability to interact with biological entities so that, for example, drug payloads can be delivered precisely to targeted areas (reducing or eliminating the “toxic trail” associated with chemo- and radiotherapy). They could also assist the body in its own regenerative processes by mimicking or guiding the biology of natural healing.
Consumer businesses use similar nanoparticles to enhance their widely available products. Unlike cancer treatments, cosmetics, for example, do not undergo the mandatory drug-testing process stipulated by the FDA, and some believe the toxicity of nanoparticles has been insufficiently tested to be so widely available in commercial products. Yet these criticisms appear largely unfounded. While nanomaterials interact with living systems differently than bulk materials, there is no reason to believe that, as a class, they are generally more dangerous. This does not mean that there are no new legitimate concerns, only that these concerns are more nuanced than fundamental.
The scientific establishment and industry acknowledge concerns about nanoparticle toxicity. Cosmetic companies invest in their own safety studies, and in 2006, the FDA launched a nanotech task force to look at safety issues. Overall, safety considerations seem to be moving in step with research and development, and industry has adopted new frameworks for studying nanoparticle toxicity as part of the product development process. Even the largely unregulated cosmetics industry funds independent studies and adheres to the FDA's stringent voluntary guidelines.
Nanotechnology also engenders concerns about the environment. Even if nanoparticle safety guidelines for particular applications are established, what if the particles are taken out of the realm of their intended use? For example, if nanoparticles are deployed in electronics and deemed safe because they are closely bound within the matrix of a circuit board, what happens if they are released into the environment when the circuit board is destroyed or disposed of? What if it catches fire? And what about waste disposal and nanotech-enabled manufacturing plants?
Again, all of these questions are predicated on the unfounded idea that nanoparticles are fundamentally more dangerous than other materials. As with any set of chemicals used in manufacturing at any scale, there should be standards about how various types of nanoparticles are handled. The National Institute for Occupational Safety and Health recently issued an initial set of best practices and safety guidelines. This is an important first step, but neither the Occupational Safety and Health Administration nor the EPA has regulations for the handling of nanoparticles (though both groups are discussing them).
Thus far, a combination of public attention and industry self-regulation has kept the nascent field safe. Nanophase, one of the few companies that makes nanoparticles in industrial quantities, sets a high standard for safety practices, operating a closely controlled and environmentally sensitive production line. Because of the precision of its production process, Nanofilm, another industrial-scale producer of nanotechnology, is able to carefully capture its waste. The waste stream is also considerably smaller than that resulting from other chemical process–in the case of Nanofilm, its annual waste stream fits into one 55-gallon drum.
This oversight and discussion is good, so long as it continues on track, or as closely as possible, with the pace of research. Halting development because of unfounded concerns would have only a profoundly negative impact for a world facing environmental hazards, disease, and other challenges that nanotechnology could lessen or resolve. Nanotechnology is in its gangly adolescence and needs time and space to grow. In the parlance of the Bulletin, it is not minutes from midnight, but rather minutes from dawn.