Size matters: towards a definition of nanomaterials for regulatory purposes
Despite the growing utilisation of engineered nanomaterials in consumer products and innovative technological applications, there is at present no widely accepted definition of the term "nanomaterial" that is suitable as a basis for legislation on their safe use. Responding to a request of the European Parliament, the JRC published today a reference report entitled "Considerations on a definition of nanomaterial for regulatory purposes".
The report discusses possible elements of a definition aiming at reducing ambiguity and confusion for regulators, industry and the general public. It recommends that the specific term “particulate nanomaterial” should be employed in legislation to avoid inconsistencies with other definitions and that size should be used as the only defining property.
A lower limit of 1 nm for the size range of interest (the "nanoscale") is considered as a reasonable figure. The upper limit of the nanoscale should be equal to or greater than 100 nm in order to include a wide range of currently used nanomaterials of regulatory concern. Other specific physico-chemical properties and attributes (e.g. state of agglomeration, biopersistance, or whether intentionally manufactured) may be relevant in the scope of particular legislation. Therefore it may be necessary to adapt the general definition to the needs of a specific implementation.
The report emphasises that the adoption of a definition will involve policy choices, and entail political decisions. Whereas there is a clear need for a consolidated definition of the term "(particulate) nanomaterial", the task of establishing a size based definition is not straightforward, and should ideally involve consultation, with stakeholders in the world of academia, regulatory bodies, industries and possibly NGOs.