Small particles can make a big difference
Nanotechnology is the design, characterisation, production and application of structures, devices and systems that entails controlling the shape and size at nanometre level.
The size range of nanotechnology is often delimited as 100 nm down to molecular level (approximately 0.2 nm) because this is where materials have significantly different properties. However, there is a certain discussion about how strictly nanotechnology should be delimited. These discussions often emphasise the need to integrate with other length scales in order to obtain wider technology development.
Nanotechnology works across professional boundaries and lines of business, resulting in new materials with new properties. For example, nanoparticles can make metals lighter, stronger and harder and they can change the electrical, magnetic and optical behaviour of a material.
Nanotechnology has been predicted by some as the basis of a new industrial revolution in the 21st century. It is indeed a technology that holds promising perspectives in a large number of areas, among others the eco-innovation area. However nanotechnology is still at an early exploratory and creative stage and not much is known about its safety and potential risks.
Potentials and perspectives
Widespread eco-potentials
Nanotechnology in general is expected to reduce energy consumption, reduce waste production, as well as increase efficiency of energy use and storage and, when used for specific surface-coating purposes, it is expected to be able to reduce or eliminate the use of harmful chemicals. Nanotechnology can also contribute to cleaner industrial production processes or products, mainly through reducing the use of raw materials and energy.
Examples of Danish nanoscience
In Denmark, the research community has embraced the potentials of nanotechnology and a variety of initiatives are being conducted in this area.
Examples of current research projects based on nanotechnology are:
Using nano-based catalysts for cleaning fine particles from diesel engines
Immobilisation and breakdown of pollutants in decontamination processes by reaction with functional nanoparticles. This is expected to be of use for example in wastewater treatment plants, for example.
Controlled release into the soil of adsorbed components from nanoparticles or films. This could result in a more controlled and efficient release of nutrient or pesticides in agriculture, for example.
Intelligent dosage systems, for example in washing machines or for dosing fertilizers in agriculture.
Coating surfaces for antifouling purposes or coating surfaces to make them antibacterial or self cleaning. This is expected to be of use in the food and medico industries and in antifouling treatment of ships.
Biosensors for monitoring specific chemicals, for example biosensors containing an oestrogen receptor will allow fast detection of hormone-like compounds.
Windows for solar and daylight control to allow better energy efficiency.
Very cheap polymer solar cells, printed on thin plastic films. These hold potential for wider distribution of solar cells.
Possible risks
Limited knowledge
Since nanotechnology is still a new technology, not much is known about the potential dangers of producing and spreading nanoparticles in the environment. There have been no studies of how the particles behave in water, soil and air, or if they are able to accumulate in food chains. It could be difficult to control the spread of nanoparticles in the environment because of their small size.
The small size of nanoparticles could also cause some undesirable health effects. The particles might be able to penetrate cells and the reaction might be harmful. Also, it is known that ultrafine particles are harmful to lung tissue. Ongoing research shows that the toxicity of nanoparticles depends on the physical form of the particles. The free particles seem to be more harmful than immobilised particles in matrices.
Research into the safety of nanotechnology is being carried out within the NANOSAFE programme which is included in the EU 5th and 6th Framework programmes.
More information on nanotechnology and eco innovation:
www.teknologiskfremsyn.dk/download/75.pdf
More examples of the technology options can be found at e.g. www.nanoforum.org.
Green Technology Foresight about environmentally friendly products and materials: http://www.mst.dk/Publikationer/Publications/2006/09/87-7052-216-2.htm