Jim Willis is the retired executive secretary of the Basel, Rotterdam and Stockholm Conventions and chair emeritus of the OECD Working Party on Manufactured Nanomaterials.
This Wednesday, the European Parliament is being asked to consider the European Commission’s current position on the use of cadmium based quantum dots in display lighting applications.
Quantum dots are part of an innovative new technology – nanotechnology – where spherical crystals smaller than a human hair are used to produce very precise coloured light in LED displays. The results are hitting the market right now in the form of a new wave of televisions, monitors and other displays that can show millions of additional colours, making them much more realistic to view. This makes these innovative displays very appealing to consumers, and helps stimulate competition in this sector towards better, more cost-effective technologies.
Quantum dots have an additional and perhaps more important benefit. Quantum dots actually deliver this performance benefit in a highly energy efficient fashion. In fact, compared with today’s display technology, a quantum dot based television will reduce energy consumption by more than 20% – potentially saving more than 3 billion Euros in energy costs and preventing the emission of 7 million tonnes of CO2 annually.
The use of quantum dots in displays is a recent development, and there is extensive research and development on the best materials for this application. Currently, the most energy efficient and reliable quantum dot for this application uses cadmium, which was restricted by the EU in 2006 along with other chemicals under the Regulation on Hazardous Substances (or RoHS) Directive.
When innovative companies were able to demonstrate that the use of cadmium in this context not only revolutionized the colour performance of displays, but in a way that would result in significant energy and CO2savings without a significant risk to health or the environment, the EU issued an exemption on this use of cadmium in 2009. This cleared the way for further product development and refinement, and the wave of great new display products that are now being sold around the world.
Several companies have now requested a 4-year extension of the previously granted exemption for this use of cadmium. It would further limit the introduction of cadmium into the EU to a maximum of 0.2 micrograms per square millimetre of display area, which amounts to less than a tenth of a gram per TV, a minuscule amount. Cadmium-based quantum dots are coated with polymer and sealed in glass, so the cadmium is not bioavailable, and the quantum dot components are themselves sealed within the displays. The risk of exposure is negligible. The only alternatives to cadmium-based quantum dots in this application are indium-based quantum dots, which are considerably more toxic, less energy-efficient, less stable, and have a much poorer colour performance than cadmium-based quantum dots.
Charting a path forward that protects health and the environment, yet facilitates the development of beneficial new technologies, has been a challenge for regulators in countries around the world. European regulators have done an outstanding job of performing a delicate balancing act in this case. Over the long term, maintaining the spirit and objectives of RoHS to phase out cadmium is important. But in the near term, precipitous action may inadvertently increase the use of substances that are more toxic than cadmium, stifle new technology, and limit competitiveness and consumer choices. Allowing only a very small amount of cadmium onto the market under closely controlled conditions and for a very short time period will allow the current benefits of quantum dots to be reaped, but will stimulate the development of safer alternatives for the future.
I remain confident that the EU will adopt an approach that gives consumers the high quality products they desire, while taking steps that encourage competitiveness and cost effective innovations, and maintaining a high standard of protection of human health and the environment. In this case, this means upholding the European Commission’s position on extending exemption 39, by voting down the motion before Parliament this week.