The European Commission (EC) Joint Research Center (JRC) announced on July 10, 2015, the publication of its third report in its review of the EC recommendation on the definition of a nanomaterial. The report is the last in a series of three, and provides scientific support to the EC in its review of the definition used to identify materials for which special provisions might apply (e.g., for ingredient labeling or safety assessment). According to JRC, as the definition should be broadly applicable in different regulatory sectors, “the scope of the definition regarding the origin of nanomaterials should remain unchanged, addressing natural, incidental and manufactured nanomaterials. Furthermore, size as the sole defining property of a nanoparticle, as well as the range of 1 nm to 100 nm as definition of the nanoscale should be maintained.” JRC notes that several issues seem to deserve attention in terms of clarification of the definition and/or provision of additional implementation guidance, however, including:
- The terms “particle,” “particles size,” “external dimension,” and “constituent particles.”
- Consequences of the possibility of varying the current 50 percent threshold for the particle number fraction (if more than half of the particles have one or more external dimensions between one nanometer (nm) and 100 nm, the material is a nanomaterial). Variable thresholds may allow regulators to address specific concerns in certain application areas, but may also confuse customers and lead to an inconsistent classification of the same material based on the field of application.
- Ambiguity on the role of the volume-specific surface area (VSSA). The potential use of VSSA should be clarified and ambiguities arising from the current wording should be eliminated.
- The methods to prove that a material is not a nanomaterial. The definition makes it very difficult to prove that a material is not a nanomaterial. This issue could be resolved by adding an additional criterion.
- The list of explicitly included materials (fullerenes, graphene flakes, and single wall carbon nanotubes even with one or more external dimensions below one nm). This list does not include non-carbon based materials with a structure similar to carbon nanotubes. A modification (or removal) of the current list could avoid inconsistencies.
- A clearer wording in the definition could prevent the misunderstanding that products containing nanoparticles become nanomaterials themselves.
According to JRC, many of the issues addressed in the report can be clarified by developing new or improved guidance. JRC notes that relying only on guidance documents for essential parts of the definition may lead to unintended differences in the implementation and decision making, however. Therefore, the report identifies and discusses possibilities to introduce more clarity in the definition itself. JRC states that it will continue to support the review process of the definition and its implementation in European Union legislation.