The recent EU Cosmetic Products Regulation includes a labelling obligation for nanomaterials in the list of ingredients, in order to allow consumers to make a choice. Similar provisions are now being considered for other regulations/directives, e.g. the Novel Foods Regulation. Also the European chemicals legislation REACH may need adjustments to address and control the potential risk of nanomaterials. The introduction of these provisions specific to nanomaterials requires the adoption of a definition of the term "nanomaterial". This need is also acknowledged by the European Parliament which has called for a comprehensive science-based definition in Community legislation.
This report reviews and discusses issues and challenges related to a definition of "nanomaterial". It gives a short overview about what may be considered as nanomaterials, their novel properties and applications. The need for a definition of nanomaterial is discussed, and the question of what should be achieved by a definition is addressed. The report gives an overview of definitions by international, national and European institutions, and lists approaches used in European legislation. It summarises the advantages and shortcomings of different elements typically used in available definitions, regarding their applicability in a regulatory context.
The following three key elements are identified as being crucial in achieving a single, enforceable definition of nanomaterial: (i) the term "material", (ii) the nanoscale, and (iii) specific nanoscale properties. Material and nanoscale should both preferably be defined precisely in order to ease enforceability. This implies the introduction of precise nanoscale limits and instructions on how such limits can be applied to nanoscale materials with size distributions. Size-derived properties, nanostructured features, nanoscale materials incorporated in a matrix and the origin of the material are also issues to be considered.
Key words: nanomaterial, definition, nanoscale, physico-chemical properties, Cosmetic Products Regulation, REACH.