In a new publication, RIVM indicates scientific challenges in the use of the EU European Union (European Union ) definition for nanomaterial in legislation. The European Commission recommends that a nanomaterial be defined as a material in which at least 50% of the number of the constituent particles is in the size range 1 - 100 nm. Regulation of nanomaterials, however, needs more than a definition alone.

In recent years, an increasing number of applications and products containing or using nanomaterials have become available. Knowledge on potential risks of these materials for humans and the environment is currently insufficient. A clear definition to discriminate nanomaterials from other materials is prerequisite to include provisions for nanomaterials in legislation. In October 2011 the European Commission published the „Recommendation on the definition of a nanomaterial‟, primarily intended to provide unambiguous criteria to identify materials for which special regulatory provisions might apply, but also to promote consistency on the interpretation of the term „nanomaterial‟. RIVM describes the current status of various regulatory frameworks of the European Union with regard to nanomaterials, and major issues relevant for regulation of nanomaterials are discussed. These include:
- What does the definition reveal about environmental, health and safety risks of nanomaterials? The current definition is based on a percentage of the particles that is smaller than 100 nm and is not aimed at mapping out the risks of nanomaterials. The choice for this size limit is pragmatic and lacks a solid scientific basis. To enable a proper risk assessment, further insight is needed into the relationship between the particle size of materials and their effects on environmental and human health.
- Are current measurement techniques for chemicals suitable for nanomaterials? There is a great variety of measurement techniques and methods available, but at present it is not clear what the most suitable technique for each case is.
- In which part of the life-cycle, from production to use, will materials be examined to fulfil the criteria of the definition? It will not be sufficient to determine only once in the life-cycle whether a material is a nanomaterial, because the size of particles (including nanoparticles) can change during the life-cycle.
This will contribute to better understanding the implications of the choices policy makers have to make in further regulation of nanomaterials.

Publication
http://dx.doi.org/10.1016/j.yrtph.2012.11.007

See also
RIVM-report:
http://www.rivm.nl/Bibliotheek/Wetenschappelijk/Rapporten/2012/juni/Interpretation_and_implications_of_the_European_Commission_s_definition_on_nanomaterials