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Collaboration in the Nano era

From filtering UV light in sun cream to preventing perspiration odour in socks and sterilising fridges and washing machines. The use of nanoparticles in products is increasing. But what is the impact of these miniscule particles on the environment?

To answer this question, four environmental researchers from Leiden University call for early cooperation. Their ‘call for action’ was published in Nature Nanotechnology.

At the Institute of Environmental Studies (CML) in Leiden, Jeroen Guinée, Reinout Heijungs, Willie Peijnenburg, Martina Vijver study the impact of nanomaterials on the environment. To analyse this, they use two different methods. Peijnenburg, and Vijver use Risk Assessment (RA) and Heijungs and Guinée the Life Cycle Assessment (LCA). ‘The past few decades there has been quite some debate about the strong and weak points of these methods and how they relate to each other,’ Guinee comments.

Similar knowledge

‘With the RA you study the environmental impact of one specific substance for a specific activity and moment. With the LCA you study the environmental impact of a product, from the moment it is being developed until the end of its use and waste management,’ Guinée explains. ‘In one specific phase of the LCA, the impact assessment phase, the environmental impact of all used substances is defined. For this phase, LCA needs similar knowledge as the RA yields. Thus, although the methods differ in goal and approach, they can complement each other.’

‘Performing a LCA is an enormous task but in the meantime many products have been analysed. For example, packaging, shopping bags, water bottles and transport systems. Nowadays, the LCA is often required in EU projects when new processes and products will be developed. This is also the case for nanomaterials. They have to be more sustainable than their predecessor.’

Ex ante

In most cases a producer orders a RA or LCA after a product is on the market. ‘Then you can conclude what you should have done differently, but after all the investments there will be little change. Preferably this knowledge is gained at the beginning of the process, beforehand. This is also called ex ante. But this is challenging’, Guinée emphasizes. ‘During the exploration and developmental phase of new materials, you do not yet know how the whole system will look like and how the materials will be applied. Just like in the early days we could not predict that Einsteins’ discoveries would end up in the mobile phone.’


At the beginning of the Nano era, during which knowledge about environmental impacts is limited, the two methods can complement each other. Through early collaboration, Guinée and his colleagues hope to bridge the knowledge gap and prevent adverse impacts of nanomaterials on the environment. Their advice: ‘Team up with a partner who masters the other method, either the RA or the LCA, and identify your common problem. Then think about what and how you can learn from each other and emphasize the necessity of both methods in your project proposal.’

Jeroen B. Guinée, Reinout Heijungs, Martina G. Vijver and Willie J.G.M. Peijnenburg. Setting the stage for debating the roles of risk assessment and life cycle assessment of engineered nanomaterials - Nature Nanotechnology, 4 August 2017

At the CML in Leiden, this kind of collaboration is ongoing for the Horizon 2020 NanoTandem project. Researchers use both LCA and RA to evaluate the application of nanoparticles to increase the efficiency of solar panels.