On July 4, 2012, the European Commission (EC) Scientific Committee on Consumer Safety (SCCS) posted its Guidance on the safety assessment of nanomaterials in cosmetics. The EC requested the SCCS develop guidance on the elements that would be required in a manufactured nanomaterial safety dossier. The SCCS states that the Guidance is intended to provide information to help compliance with the requirements for the safety assessment of nanomaterials intended for use in cosmetic products.  The Guidance describes the need for special considerations in relation to the safety of nanomaterials, in view of the possible distinct properties, interactions, and/or effects that may differ from the conventional form of the same materials.  The Guidance includes the main elements of risk assessment of nanomaterials in relation to possible use as cosmetic ingredients, i.e., general safety considerations, material characterization, exposure assessment, hazard identification and dose-response characterization, and risk assessment. The Guidance notes that the Cosmetics Regulation No 1223/2009 defines nanomaterial as “an insoluble or biopersistent and intentionally manufactured material with one or more external dimensions, or an internal structure, on the scale from 1 to 100 nm,” and that this definition could be revised in light of the EC’s October 2011 Recommendation on the  definition of a nanomaterial. According to the Guidance, if the Cosmetics Regulation definition were aligned to the Recommendation, it would provide further information on whether a material falls under the definition of a nanomaterial.