Nanomaterials are chemical substances or materials that are found or manufactured to extremely small sizes (the nano scale).  Nanomaterials are ca. 1 – 100 nanometres (10-9 metre) in at least one dimension.

The EU COM defines a nanomaterial as:

A natural, incidental or manufactured material containing particles, in an unbound state or as an aggregate or as an agglomerate and where, for 50 % or more of the particles in the number size distribution, one or more external dimensions is in the size range 1 nm - 100 nm.

In specific cases and where warranted by concerns for the environment, health, safety or competitiveness the number size distribution threshold of 50 % may be replaced by a threshold between 1 and 50 %.

By derogation from the above, fullerenes, graphene flakes and single wall carbon nanotubes with one or more external dimensions below 1 nm should be considered as nanomaterials.

Nanomaterials have the potential to have very different physico-chemical properties from the same substance or material at conventional scale (bulk material), such as increased reactivity, increased strength etc.  Considerable interest has grown in nanomaterial research over the past number of years because of their potential to have a positive impact on quality of life and industrial competitiveness in the EU.  Nano innovation has the potential to have a positive impact on a large number of sectors including employment, public health, occupational health and safety, environment, energy, agriculture etc.

Although the positive potential of nanomaterials is recognised, it is also readily acknowledged that nanomaterials have the potential to pose risks to the environment and raise health and safety concerns.  The Scientific Committee on Emerging and Newly Identified Health Risks have noted that although nanomaterials are not dangerous per se, there remains scientific uncertainty about the safety of nanomaterials in many aspects and therefore the safety assessment of the substances must be done on a case-by-case basis.

The Pesticide Registration and Controls Divisions of DAFM are interested in nanomaterials because they have the potential to be found in pesticide products (biocide and plant protection products).  Nanomaterials are explicitly mentioned in the Biocides Products Regulation and this regulation contains specific nanomaterial provisions.  The nanomaterial definition stated in the Biocides Product Regulation is based on the EU definition provided above.