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VigilNanos - Revision of the definition of the term "nanomaterial" by the European Commission

Revision of the definition of the term “nanomaterial” by the European Commission

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Revision of the definition of the term “nanomaterial” by the European Commission (2014-2022)

By AVICENN Team – Last Modified July 2022

The result of the revision of the recommendation for the definition of the term “nanomaterial” was published in June 2022; it marks the end of a long suspense (the revision had been expected since 2014!) and the beginning of a new adventure: the clarifications announced are not necessarily there and it's a safe bet that the quarrels will not have not finished flourishing on the qualification (or not) of certain substances as “nanomaterial”…

The “revised” definition recommendation was published in June 2022

On June 10, 2022, the Commission published its revised recommendation for the definition of the term “nanomaterial”, which replaces its previous recommendation from 2011. It is worded as follows:

We hear by “nanomaterial” a natural material, accidentally formed or manufactured, consisting of solid particles* which are present either individually or as identifiable constituent particles in aggregates** or agglomerates**, at least 50% of these particles, in the numerical distribution by size, meeting at least one of the following conditions:

(a) one or more external dimensions of the particle* fall within the range from 1 nm to 100 nm

(b) the particle* has an elongated shape, such as that of a rod, fiber or tube, two outer dimensions being less than 1 nm and the other dimension greater than 100 nm

(c) the particle* has a plate shape, one outer dimension being less than 1 nm and the other dimensions greater than 100 nm.

To determine the numerical particle size distribution, it is not necessary to consider particles having at least two orthogonal external dimensions greater than 100 μm.

A material with a specific surface area by volume of less than 6 m2/ cm3 however, is not considered a nanomaterial.

* “particle”: a tiny fragment of matter possessing well-defined physical contours; single molecules are not considered "particles"

** “aggregate”: a particle made up of welded or fused particles

*** “agglomerate”: a friable mass of particles or aggregates whose overall external surface corresponds to the sum of the surfaces of its individual constituents.

A slow and tedious project, 8 years late

As a reminder, this revision should have taken place in… 2014! In 2011, the European Commission published a first definition recommendation which had caused a lot of ink to flow. It was planned from the outset that this definition would, if necessary, evolve from 2014. In the end, after years of procrastination and postponements, this new definition was published in mid-2022, i.e. eight years later. the scheduled deadline.

Chronology of a review repeatedly postponed

At the 12nd CASG nano meeting in March 2014, the European Commission confirmed that this 2011 recommendation would be reviewed as planned.

The, same month, the Joint Research Center (JRC) had organized a technical workshop on this subject, then led a scientific discussion on the challenges posed by the application of the definition in European regulations and published various reports and recommendations aimed at improving the content and implementation of the future definition1In 2014 and 2015 the JRC published a first analysis report (See: Towards a review of the EC Recommendation for a definition of the term “nanomaterial” – Part 1: Compilation of information concerning the experience with the definition, JRC, March 2014), followed by an evaluation report (Towards a review of the EC Recommendation for a definition of the term “nanomaterial” – Part 2: Assessment of collected information concerning the experience with the definition, JRC, September 2014) followed by a third report of recommendations aimed at improving the content and implementation of the future definition (See Towards a review of the EC Recommendation for a definition of the term “nanomaterial”: Part 3: Scientific-technical evaluation of options to clarify the definition and to facilitate its implementation, JRC, July 2015).

La public consultation was postponed to 2015, then 2016 and October 2020, after many twists and turns2At the beginning of May 2017, rumors in the hallway reported an imminent publication... and at the beginning of July, the specialized press evoked a publication during the summer. In particular, the Commission confirmed, in mid-March 2017, before the Casg nano, that its draft revision would be subject to a public consultation 6 weeks after its publication, in order to be adopted in the second half of 2017 and accompanied by an explanatory note. carried out by the Joint Research Center (JRC) attached to the Commission. A public and stakeholder consultation on the “roadmap” did take place from mid-September to mid-October 2017, but it focused on the method, objectives and general principles guiding the development of the revised definition, more than on the precise content of the new definition. 18 contributions have been made, by industrialists, environmental agencies and a few anonymous citizens. The roadmap mentions a 12-week consultation in the first quarter of 2018, but at the end of February 2019, the feedback received from Brussels reported a more than likely postponement of the publication of the draft and the consultation to 2020 (see EU revision of nanomaterials definition postponed to 2020, Chemical watch, February 26, 2019), the European Commission again reiterated its desire to revise the definition of the term “nanomaterial” in its Chemicals Strategy (Chemicals strategy for sustainability, CSS) and to ensure its “consistent application across legislation using legally binding mechanisms”. THE'Annex specified the date: 2021 only…

The 7 May 2021, the European Commission actually ended up publishing its proposal and launching a online consultation, until June 30, 2021.

  • The AVICENN Association had posted his contribution, without commenting on issues outside its field of competence, but taking care to fulfill its watchdog role, recalling the broader expectations of civil society in favor of a better regulatory framework to ensure the protection of health and the environment.
  • In one communicated summary published on its website, the French National Health Security Agency (ANSES) summarized the content of its response to the European consultation on the definition of the term "nanomaterial", without yet revealing its full content: ANSES considered that “the modifications suggested by the Commission tend to restrict the number and the nature of the objects which will ultimately be considered as nanomaterials” and pleaded on the contrary for a definition as inclusive as possible, which does not exclude nanoplastics, emulsions and lipids of nanometric scale. It also underlined, as did AVICENN for its part, the lack of scientific basis for the size thresholds (1-100 nm).

Mid-August 2021, the European Commission then published the 136 contributions collected, as well as additional contributions French authorities, of the Industrial Minerals Association (IMA) and from the German Federal Institute for Risk Assessment (BfR). The Commission then indicated that it was carrying out a " Detailed analysis " with a view to publishing, by the end of 2021, a summary and statistical analysis of the responses, as well as its plans for the potential revision or replacement of the current definition recommendation.

In February 2022, noting that the Commission had, once again, not kept its commitments (still no summary or analysis of the contributions to the consultation yet promised for the end of 2021), fifteen NGOs sent a open letter to the European Commission asking it to clarify and improve its definition of the term "nanomaterials" by opening the discussion so that this definition can be reworked, collectively, and will then be included – with or without adaptation? – to the various European regulations.

Points of questioning and controversy

As a reminder, previous definition recommendation from 2011 had been challenged:

  • both by manufacturers who found it too broad
  • only by NGOs who, on the contrary, considered that it was too restrictive and left out many nanometric materials.

The new 2022 recommendation is also a source of criticism (some are common to the 2011 definition, others are specific to the new 2022 version). Announced clarifications are not necessarily there3despite the details provided by the Committee staff working document (SWD(2022) 150) and it's a safe bet that the quarrels have not finished flourishing over the qualification (or not) of certain substances as “nanomaterials”. Evidenced in particular by the reaction of the NGO CIEL published on June 14, 2022 and thearticle from ChemicalWatch relaying the dissatisfaction of CIEL and AVICENN on June 15, 2022. The reservations expressed by ANSES on the pre-draft submitted for consultation in 2021 (see below) were also not taken into account by the Commission4See Scientific and technical support note relating to "the development of a proposal for an updated definition of the term "nanomaterials" based on Recommendation 2011/696/EU", ANSES, 14 January 2022; another ANSES report, this time on the final version of the 2022 recommendation, is being prepared. Georges Favre, from the National Metrology and Testing Laboratory (LNE), is less critical of this new definition5See The Commission publishes its new definition of nanomaterials, Environment News, July 21, 2022.

What about above 100 nm?

Regarding the 1-100nm range (identical to that of 2011), there is no scientific justification to establish an upper and/or lower size limit to define all nanomaterials6See in particular:
- Nanomaterials: for a more protective European definition, ANSES, July 23, 2021
- AVICENN's contribution to the European consultation on the definition of the term "nanomaterial", AVICENN, June 30, 2021
- Scientific Basis for the Definition of the Term “nanomaterial”, SCENIHR, European Commission, 2010
. Results of toxicological studies report toxic effects generated specifically at the submicron scale exceeding 100 nm, in particular up to 600 nm. The American Food & Drug Administration (FDA) has thus chosen to define a nanomaterial as a material in which at least one of the dimensions is less than 1000 nm7See Reporting Format for Nanotechnology-Related Information in CMC Review, Office of Pharmaceutical Science (FDA), June 2010.
A team of Chinese and American researchers had published an article on this subject in February 20148Bai Y et al., 100 Nanometers: A Potentially Inappropriate Threshold for Environmental and Ecological Effects of Nanoparticles, About. Science. Technology., 48 (6): 3098-3099, 2014.

What about nano-structured materials internally?

Unlike the ISO definition, the European definition recommendation of 2022, like that of 2011, excludes internally nano-structured materials9The International Organization for Standardization (ISO) defines a nanomaterial as being "a material having any nanoscale external dimension or nanoscale internal or surface structure" (the nanometric scale is defined as a spectrum of dimensions from about 1 nm to 100 nm); she adopted the term NOAA to encompass all “Nano-Objects, their Agglomerates and Aggregates greater than 100 nm”.

Exclusions of different categories of materials

In addition to these grievances, there are additional questions about the new formulations adopted by the 2022 recommendation: the latter does not take into consideration, for example, the questions and reservations of ANSES in particular10Scientific and technical support note relating to "the development of a proposal for an updated definition of the term "nanomaterials" based on Recommendation 2011/696/EU", ANSES, 14 January 2022 and should lead to the exclusion of nano-objects hitherto considered as nanomaterials:

  • the introduction of the term "solid" excludes gaseous and liquid particles, in particular emulsions and micelles (the latter, used for medical applications, have an increased ability to pass certain biological barriers)
  • the exclusion of "single molecules" could deviate from the definition of nanoplastics, fullerenes and, once again, nanomicelles and lipid structures used as carriers
  • the exclusion of nano-composites could be used by certain brands to escape regulatory constraints on the grounds that their ingredients are complex compounds, in which several substances are present (for example nanoparticles of titanium dioxide coated with silica or grafted onto mica plates, used in particular in cosmetics).

Removed the ability to lower the threshold by 50%

The rate of 50% of particles by number below the 100 nm mark is identical to that of 2011 (and more than 333 times higher than that defended by the Scenery (0,15%) in 201011 See Scientific Basis for the Definition of the Term “nanomaterial”, SCENIHR, European Commission, 2010: the Scenihr insisted on knowledge of the size distribution of a nanomaterial and on the need for a distribution in number (more relevant than a mass distribution defended by industrialists) ; as a reminder, at the time, even German industry did not ask for so much: she had campaigned for a rate of around 10% “only”). However, the Commission had provided in 2011 that in the event of concerns in terms of environmental or health risks, this rate could be lowered below 50%. This was argued in particular by the French authorities12See Nanomaterials – Evaluation of the national R-Nano declaration systemDecember 2020. The industrial federations, on the contrary, opposed it13See EU Plans to Review the Definition of a Nanomaterial, Nanotechnology Industries Association (NIA), December 3, 2020 and won their case during the revision of the recommendation, since the European Commission skipped this clause in the definition of 2022, which fixes the rate at 50% without the possibility of lowering it from now on. This deletion now makes it possible not to consider as nanomaterials (and therefore not to regulate accordingly) substances of which 49% of the particles in number would be made up of particles below the 100 nm mark. Exit health and environmental considerations?

Take the specific case of cosmetics: the definition of the current Cosmetics Regulation does not include a threshold, French authorities have used a 10% threshold so far ; the transposition of a fixed threshold of 50%, would exempt from labeling and notification thousands of cosmetics containing nanoparticles some of which are potentially dangerous for consumers.

What scope for this revised definition?

Towards transpositions with or without adaptation(s) in European regulations?

Will the revised definition be transposed to all Community regulations, whatever their field of application? Not immediately in any case: to change the definition of European regulations in order to bring them into line with the Commission's definition recommendation, it requires a specific co-decision review process which can take, in some cases, several years.

The Commission has clearly indicated its wish to see its revised recommendation become “binding”, from a legal point of view; it should therefore eventually be transposed into the regulation REACH (this is expected by the end of 2022) and other EU regulations with provisions on nanomaterials – starting with the one on cosmetics (the work is in progress), then thefood, biocides, medical devices mainly (what about regulation on plant protection products and the draft revision of the Industrial Emissions Directive (IED) aimed at reducing emissions of pollutants?).

Will this definition be transposed as is or accompanied by adaptations or management measures aimed at minimizing the health or environmental risks of the materials “showing nano-scale properties” but not covered by the revised definition recommendation?
The ongoing revision of the Cosmetics Regulation14See Towards a new nano definition in the future Cosmetics Regulation… yes, but which one?, EveNanos, July 13, 2022 will be, with REACH, the first “test” and could set a precedent.

More than legal consistency and security, it is health security that must prevail

Harmonization of terminology was requested by manufacturers in order to put an end to the difficulties caused by the coexistence of different definitions which complicates the work of producers / importers / distributors: the latter complain of having to declare and label "nanomaterials" defined differently in various national registers (Such as r-nano in France), In REACH at European level and in sectoral regulations (food, cosmetics, biocides, medical devices, etc.). But harmonization of definitions must not be at the expense of public health and the environment. Problems related to the coexistence of different definitions is a problem that could be solved upstream of the chain of the supply chain: whether companies that produce and/or blend nanomaterials carry out a precise and complete characterization of substances and transmit information correctly, downstream actors can apply the appropriate definition to their sector and apply the appropriate measures : labelling, recording and notification where applicable. 

An operational and unique definition: “mission impossible”?

Defining what a nanomaterial is and revising current definitions are complex approaches, both scientific and very political, with multiple implications for companies as well as for lawyers and public authorities. The exercise is so perilous15For a synthetic analysis of the ins and outs of the debates around a single definition of nanomaterials, see the article by Georgia Miller and Fern Wickson "Disagreement Over Definitions Including Relevant Size, Size Distribution, Intentionality of Production, and Occurrence of Novel Properties" in Risk Analysis of Nanomaterials: Exposing Nanotechnology's Naked Emperor, Miller G and Wickson F, Review of Policy Research, 32(4): 485, July 2015. that scientists even advise against complying with it. For a long time, the French authorities also did not push for the revision of the definition at European level: it is in fact on the latter that was built the R-Nano system for the annual declaration of "substances in nanoparticle state", mandatory in France since 2013.
NGOs are also skeptical16At the CASG nano meeting in March 2014, the European Environmental Bureau (BEE) had criticized the Commission's eagerness to launch this project: advances in the characterization and metrology of nanomaterials have certainly evolved since 2011, but not enough according to the EEB to justify a revision of the definition. This project, necessarily time-consuming and involving significant public expenditure, is less important and urgent than others, at the time neglected by the Commission, in particular:
- adaptation of the REACH annexes to nanomaterials (finally approved in 2018, even if its implementation is still incomplete in mid-2020)
- the establishment of a community register of nanoproducts on the European market.

Like Andrew Maynard before them17Don't define nanomaterials, Maynard A, Nature, 475, July 2011, French researchers consider that “uinstitutional definition is not a sine qua non condition for managing risks and that the absence of definition or, in this case, the multiplicity of definitions coming from multiple sources, does not create either a vacuum or an aggravation of the difficulties of apprehension of risk management issues“. The researchers also consider thata single definition, if it wants to remain operational, cannot embrace all the complexity of the questions relating to the nano state of a particle. A scientific definition of nanoparticles and nanomaterials is not specifically useful for studying whether or not they pose a health risk or more broadly for the environment« 18CERTOP, The mobility of “nano” risks, September 2014.

What strategies on the part of companies that produce and/or use nanos?

Manufacturers can resort to avoidance strategies, with the development of nanomaterials whose size and number distribution can flirt with the set thresholds (with a little more than 50% of the particles exceeding 110 nm for example) in order to escape regulation... while maintaining the desired properties.

While manufacturers may have an interest in defending a definition of nanomaterials that is as narrow as possible, in order to remove as many materials as possible from regulations, market leaders could have an interest in ensuring that the definition and the information to be provided (particularly in the context of REACH) are very specialized, which would give them a competitive advantage over other companies that have less resources (technical and financial).

Another way of proceeding, more in line with the corporate social responsibility (CSR), consists in any case of being part of a co-vigilance approach: anticipate the impacts of a massive use of these materials with specific properties of the nanometric scale and their release into the environment in order to favor the choice and theeco-design of the least dangerous materials (“safe by design”) and minimize the risks throughout the life cycle, share information with the other actors upstream and downstream of the production chain (up to the final consumer), etc.

To be continued…

Elsewhere on the web

A remark, a question? This sheet produced by AVICENN is intended to be supplemented and updated. Please feel free to contribute.

The next nano appointments

“Nano and Health” dialogue committee (ANSES, Maisons-Alfort)
Dialogue Committee
  • 14th meeting of the “nano and health” dialogue committee
  • Organizer: ANSES
  • Website :
Nanomaterials, how to identify them more efficiently? (LNE, Paris)
  • Technical Day
  • Organizer: National Metrology and Testing Laboratory (LNE)
  • On the agenda: identification of nanomaterials, recent technological innovations in terms of particle size characterization, areas for progress to be considered 
  • Upcoming program
  • Website :…
NanoSafe conference 2023 (CEA, Grenoble)
  • 8th International Conference on Health Issues for a Responsible Approach to Nanomaterials
  • June 5-9, 2023
  • Organizer: Commissariat for Atomic Energy and Alternative Energies (CEA)
  • Website :…  

Sheet initially created on April 9, 2014

Notes & references

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