Nanomaterials are chemical substances or materials that are manufactured and used on a very small scale. Their structures range from approximately 1 to 100 nm in at least one dimension.

Nanomaterials have unique and more pronounced characteristics compared to the same material without nanoscale features. Therefore, the physico-chemical properties of nanomaterials may differ from those of the bulk substance or particles of a larger size.

Nanotechnology is rapidly expanding. A large number of products containing nanomaterials are already on the European market (e.g. batteries, coatings, anti-bacterial clothing, cosmetics, food products). Nanomaterials offer technical and commercial opportunities, but may pose risks to the environment and raise health and safety concerns for humans and animals. Although there are no explicit requirements for nanomaterials under REACH or CLP, they meet the regulations' substance definition and therefore the provisions apply. Further general information is described on the ECHA website (nanomaterials).