"Nanotechnology is based on the premise "smaller is better". Is this a correct premise?

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1 SCHOOLS DEBATES 2011 PROVINCIAL TOPIC "Nanotechnology is based on the premise "smaller is better". Is this a correct premise? Nanotechnology (or nanotech ) is the engineering of functional systems at the atomic and molecular scale. It is also referred to as molecular manufacturing. This basically means the human manipulation of atoms and molecules (which are invisible to the naked eye) into tiny little machines that perform useful tasks. The word nano is used because it describes the tiny scale on which nanotechnology operates between 1 and 100 nanometers. A nanometer (nm) is 1 millionth of a millimeter. This is the realm of atoms and molecules. For example, the typical distance between two carbon atoms is nm and the diameter of a DNA strand is roughly 2 nm. The smallest life form we know of (a single cell bacterium) is about 200 nm in size and thus too large be considered a typical nanomaterial. Why are we even interested in things that are so small? The properties of materials depend on how their atoms are arranged. If we rearrange the atoms in coal, we can make diamond. If we rearrange the atoms in sand, and add a few other trace elements, we can make computer chips. What nanomaterials are already in use? Examples of well-known nanomaterials are nanoparticles and carbon nanotubes (CNTs). Colloid science has given rise to a number of nanoparticles, such as quantum dots, which can be used in display technology, lighting, biological imaging and solar cells. Carbon nanotubes (CNTs) can be used as nanowires since they exhibit charge-transmitting properties and thus have applications in nanoscale electronics. 1

2 Given the massive potential benefits of nanotechnology that sometimes sound like science fiction, we should carefully look at the possible risks associated with the technology. Is smaller always better or are there instances where smaller may be worse? Below is a range of issues for you to consider. In discussing and debating this topic, you should consider the following 5 pillars of science communication: Utilitarian Nanotechnology has been heralded as having massive potential in the medical world. Drug delivery would be made more efficient, so instead of taking medicine for your lungs that would have an unintended, harmful effect on your kidneys; the medicine can be delivered directly to your lungs using nanomaterials. Nanotechnology can also be used to improve the quality of food and nutrition. One of the major drawbacks of nanotechnology when used in this way is as a direct result of the size of the materials used. Materials reduced to the nanoscale can suddenly show very different properties compared to what they show on a macroscale. For example: inert materials become catalysts (platinum); stable materials become combustible (aluminum); solids turn into liquids at room temperature (gold); insulators become conductors (silicon); there is increased reactivity associated with decreased size. Troubling reports have surfaced where nanoparticles single-walled carbon nanotubes (see the image above) aspirated by mice resulted in nanotoxicology. The mice became ill with pneumonia, oxidative stress, acute inflammatory/cytokine responses, fibrosis, and decreased heart function. This is evidence that nanomaterial could have devastating health effects on human beings when used for medicine or nutrition. Socio-cultural All the potential benefits of nanotechnology may have some socio-cultural effects. If nanotechnology provides a means of production that replaces an existing industry, people s way of life will be affected. For example, if we discover a way to manipulate atoms such that foods can be engineered as opposed to grown on farms, there will be a massive impact on the agricultural sector in several countries worldwide. Another example is the use of nanotechnology in medicine. It has been used as a means of detecting cancer in the early stages and currently research is being done on the use of nanoparticles for drug delivery. 2

3 This would decrease the mortality rates in countries with high cancer rates. There is also the possibility that nanotechnology will be rejected as a form of technology based on ethical and cultural grounds. There is a prevalent belief in society, which also applies to genetic engineering and stem cell research that we, as humans, should not tamper too much with the natural world. Manipulating atoms and molecules oversteps the boundary of comfortable human intervention in the world for many people. Economic Harnessing the production and earning potential of nanotechnology could fundamentally alter the traditional wealth patterns in the world. If a third world country, for example, was to design a nano-computer that they could sell to the world, it could develop an industry around the production of that nano-product, leading to huge economic growth. It is unlikely; however, that such a scientific breakthrough will happen outside the already resource-rich first world. At a micro-economic level, there is the real threat of nanotechnology replacing human beings for even menial labour. Window manufacturers Pilkington and PPG Industries, for example, offer self-cleaning windows coated with nanoparticles that catalyse dirt and cause rainwater to sheet down and wash away the grime rather than bead up. The same technique is being developed for self-sanitising tiles in restaurants and hospitals. Lee Jeans and Eddie Bauer offer spill-resistant pants using "nanowhisker" fabric technology developed by NanoTex. NanoTex fabrics feature billions of 10-nanometer-long nanowhiskers that repel moisture and stains. In this instance the technology replaces the jobs of people and has ripple effects on their families and the economy of the country at large. These jobs are generally easier to acquire than jobs that require specific skill and knowledge. The production of nanotechnology itself would be limited to the upper crust of society that can afford the education required to produce technology (consider that only 1% of the world is able to access university! This 1% effectively becomes the people putting thousands of people out of work). It is anticipated that nanotechnology will increase the power of corporations and governments while further disenfranchising the poor. 3

4 Democratisation of Science Nanotechnology, as with any other area of science, will be subject to patents. This means that the individuals, or companies, that develop useful nanotechnologies will be the only people who can produce that technology. Other companies (or government) may use that technology, but will have to pay royalties to those who came up with it. This places a financial hurdle in the way of using the benefits of nanotechnology for average citizens. However, this is no different from the way drugs and medicines are currently invented, produced and sold. The question is whether these nanotechnologies will be worth their price! Advancement of science Nanotechnology will undoubtedly benefit many areas of scientific research, from engineering to biology. The ability to manipulate atoms and molecules in a nano scale will be useful to almost all the science field, and hence nanotechnology can be viewed as the new frontier in scientific development and research. Again, however, regulation will play a role in what kind of nanotechnology (either beneficial or harmful) emerges. 4

5 Suggested Further Reading: Nanotechnology & Society: Current and Emerging Ethical Issues 8fd&pi=0%23section=206685&page=1%20 The South African Nanotechnology Institute The Economist Center for responsible nanotechnology The Foresight Institute Nanotechnology information Eric Drexler blog SA Nanotechnology Innovation Centers South African Nanotechnology Initiative Compiled by MUNSA 5