European Commission publishes updated definition of nanomaterials


The European Commission clarifies the definition of nanomaterials in a new recommendation. The new definition supports a coherent EU regulatory framework for nanomaterials and helps to align legislation across all sectors. The new version, dated June 10, 2022, will be used in all EU and national legislation, policies and research programs from now on.

Nanomaterials as innovation drivers with "risks and side effects"

The special properties of nanomaterials are an important driver for innovation, but may also increase the toxicity of the material or require specific precautions for safe use. Therefore, several pieces of EU legislation contain additional provisions on nanomaterials to ensure adequate data collection, risk assessment and, in selected cases, labeling of products to inform consumers about the presence of nanomaterials. The decision on whether to enact these provisions is based on an applied definition of nanomaterials.

EU legislation for the food and cosmetics sectors still has individual definitions of nanomaterials, while other EU legislation (e.g. REACH, Biocidal Products Regulation, Medical Devices Regulation) and some national legislation already use the common definition from Commission Recommendation 2011/696/EU, which is legally binding in its scope.

Until now, the European Commission Recommendation 2011/696/EU1 defined whether a material should be considered a "nanomaterial" for legislative and policy purposes in the Union. Between 2013 and 2021, the Commission now conducted a review of the 2011 Recommendation (2011/696/EU), addressing the objective, scope, clarity and use of the definition of nanomaterials. The revision focused in particular on whether the 50% size distribution threshold based on particle number should be increased or decreased, and whether to include nanoscale materials with internal or surface structure, such as complex nanocomponent materials, including nanoporous materials and nanocomposite materials that may be used in certain sectors.

The new definition: similar but not equal

The definition of nanomaterials has now been updated in Recommendation 2011/696/EU as follows:

"nanomaterial" means a natural, incidental or man-made material consisting of solid particles, either individually or as identifiable particles in aggregates or agglomerates, in which a number of 50% or more of these particles meet at least one of the following three conditions:

  • one or more external dimensions of the particle are in the size range of 1 to 100 nm;
  • the particle has an elongated shape, such as a rod, fiber or tube, where two outer dimensions are less than 1 nm and the other dimension is greater than 100 nm;
  • the particle has a platelet-like shape with one outer dimension smaller than 1 nm and the other two larger than 100 nm.

Particles with at least two orthogonal outer dimensions larger than 100 μm need not be considered when determining the size distribution based on the particle number. The additional reference to specific surface area (based on volume) is omitted as a criterion in the new definition. However, materials with a specific surface area of less than 6 m2cm-3 are generally not considered nanomaterials.

Liquid particles such as droplets and micelles are excluded from this definition, just like (macro)molecules, even if they meet the dimension criterion. The definition also does not apply to large solid products or components, even if they have an internal structure or surface structure at the nanoscale. DIt could be, for example, coatings, certain ceramic materials, and complex nanocomponents, including nanoporous and nanocomposite materials. Further details and comments can be found in the original document (see link below).

Following this update of the nanomaterial definition, the European Commission will now work to align the relevant legislation across all sectors.