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Nanomaterials’ (bio)degradation, persistence, and safe by design (SbD) examined in a recent study


A desk study commissioned by the European Union Observatory for Nanomaterials (EUON) provides information on the state-of-the-art, the existing gaps, and the research needs of the degradation, biodegradation and persistence of nanomaterials. The study also points out the need for a common definition for ‘safe’ or ‘safer-by-design’ – the process of including safety at the earliest stage of product development – to increase the societal acceptance of nanomaterials.


Helsinki, 12 December 2022 – As the number and complexity of nanomaterials increase, there is a need to address how these nanomaterials will behave in the human body and in the environment. A recent study commissioned by the European Union Observatory for Nanomaterials (EUON) aimed at providing information on the state-of-the-art, the existing gaps, and the research needs for the (bio)degradation and persistence of nanomaterials and their relevant organic coatings. Another objective of the study was to examine the current state-of-the-art for safe by design (SbD) nanomaterials, as it relates to the degradation and persistence of nanomaterials.

The study finds that the work taking place in the field of (bio)degradation of nanomaterials focusses mainly on carbon-based and organic nanomaterials, many of which are more easily degraded compared to inorganic nanomaterials, although certain organic nanomaterials are very persistent as well. Certain organic nanomaterials (e.g., biopolymers, lipids) are the easiest to degrade, while carbon-based nanomaterials are more persistent in vivo. 

According to the study most of the test guidelines used for studying the degradation and persistence of chemicals have also been applied to nanomaterials, with or without modifications. A wide range of techniques have been used where enzymatic degradation is the most studied mode of degradation. The report states this means that a potential research gap exists in the study of cell and bacterial degradation.

The study reports that a lot of work is being performed for the SbD nanomaterials within Europe and globally. A lack of consensus exists on how to define ‘safe-by-design’ nanomaterials. This is mostly due to the vagueness of the term safety itself, but also because of the unique nature of nanomaterials and their different properties, varying strongly between nanomaterial types. 

The study finds there are already proposed SbD strategies available for nanomaterials. There are fields where SbD is more advanced due to specific requirements, such as in nanomedicine. Of interest is the concept of ‘safe-by-degradation’, which implements the concept of optimised life-time of a nanomaterial to SbD including its safe clearance from the body and the environment. And, in the case of carbon nanotubes (CNTs), it has been suggested that decreasing their length leads to decreased toxicity, although this approach is not able to fully eliminate any adverse effects. 

In the expert survey that complemented the study’s literature search, 30% of the survey participants suggested that the sustainability domain should be part of the SbD framework and specifically integrate the environmental and societal dimension.



The “Study on (bio)degradation, persistence and safe by design of nanomaterials” was commissioned by the European Union Observatory for Nanomaterials (EUON), which is hosted and maintained by ECHA. EUON publishes information about nanomaterials on the EU market and is funded by the European Commission.

The study was carried out by NovaMechanics Ltd.


Further Information

Study report