How nanoparticles are counted in global regulatory nanomaterial definitions.

Nanomaterials are now generally considered materials with features at the nanoscale, i.e. between 1 nm and 100 nm, which legislation has taken up. Legislation requires clear terminology, and legislators have gradually established, individually and independently per country/region, nanomaterial (working) definitions. One major difference between these nanomaterial definitions is how they address agglomerates and aggregates, which may each be counted as one particle or their constituent particles are counted. Thus, potentially the same material may be classified as a nanomaterial, or not, depending on the definition used. OECD’s global regulatory test guideline for measuring nanomaterial size is silent on how to count agglomerates and aggregates. To achieve convergence, the first step is recognising the differences between the nanomaterial definitions and an international agreement on particle counting methods would be another step towards harmonisation. For the meanwhile, we propose a naming convention which indicates the key criteria of a specific definition of nanomaterial.

RASMUSSEN Kirsten;  RIEGO SINTES Juan;  RAUSCHER Hubert; 

2024-02-20

NATURE PORTFOLIO

JRC134667

1748-3387 (online),   

https://doi.org/10.1038/s41565-023-01578-x,    https://publications.jrc.ec.europa.eu/repository/handle/JRC134667,   

10.1038/s41565-023-01578-x (online),