Figure 1
From: Why are nanomaterials different and how can they be appropriately regulated under REACH?
Schematic illustration of different forms of a substance. (i) Bulk form with different surface modifications; (ii) bulk form and nanoforms of the same substance, nanoforms shown with different sizes and different surface modifications; (iii) nanoforms of a substance with different sizes without having a corresponding bulk form (e.g. fullerenes, carbon nanotubes).