Regulatory preparedness for multicomponent nanomaterials: Current state, gaps and challenges of REACH.

In 2018 the European Commission adopted revisions to the Annexes of Regulation (EC) No 1907/2006 concerning registration, evaluation, authorisation and restriction of chemicals (REACH) to introduce nanomaterial-specific clarifications and provisions. Multicomponent nanomaterial (MCNM) is a non-regulatory term that has been used in recent EU-funded projects to describe nanomaterials with a complex structure and/or composition and which are expected to be increasingly used in products in the near future. This paper examines the regulatory preparedness of REACH, and its revised Annexes, for MCNMs. Several situations have been identified where there is potential confusion and uncertainty around how regulatory definitions used in REACH should be applied to MCNMs. If a MCNM cannot be identified as falling within a specific definition, understanding the regulatory obligations that apply to it is very difficult. Examples of these grey areas include how the term "surface functionalisation or modification" applies when a chemical is physisorbed to the surface of a nanoform, and the identity of the substance that should be registered when the modification takes it outside the definition of a nanoform. We conclude that the regulatory preparedness can be improved by amending the REACH guidance on information requirements for nanoforms and revising the definition of "nanoform" in line with the updated EC Recommendation on the definition of nanomaterial.