30. June 2022

New OECD test guideline for determining the particle size of nanomaterials

Work by BAM, BAuA and UBA provides decisive milestone for standardised testing of nanomaterials

Sample preparation for the measurement with SAXS © BAM

The OECD has published a new test guideline for the measurement of spherical and fibrous nanomaterials. It is an important building block for the implementation of legal requirements for chemicals, such as the REACH Regulation. The OECD Test Guideline No. 125 was developed in a joint project of the Bundesanstalt für Materialforschung und -prüfung (BAM), the Federal Institute for Occupational Safety and Health (BAuA) and the Federal Environment Agency (UBA) in cooperation with 29 other institutions from four continents. The work was funded by the Federal Ministry for the Environment, Nature Conservation, Nuclear Safety and Consumer Protection (BMUV).

Nanomaterials are now widely used in products, including in the medical and automotive sectors. In order to assess them in terms of their toxicity to humans and the environment, standardisation of measurement methods is necessary. Previous OECD test guidelines were developed primarily for easily soluble organic chemicals. However, nanomaterials differ from that of readily soluble organic chemicals and therefore require nano-specific test guidelines.

In order to verify the test guideline for nanomaterials developed in the research project, a global round robin test was conducted. Results have shown that the reproducibility of the size determination of nanoparticles and nanofibres is significantly increased, thus creating a uniform basis for future work. As a result, 8 standardised measurement methods are available now for the size determination of spherical nanoparticles. Fibrous nanomaterials can be uniformly tested using electron microscopy (TEM/SEM).

Further information

The OECD Test Guidelines fall under the OECD Mutual Acceptance of Data (MAD) system. Under this system, laboratory test results for the purpose of safety assessment of chemicals prepared in accordance with the OECD Test Guidelines and the OECD Principles of Good Laboratory Practice are accepted in all OECD countries.



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Press release BAM, 30 June 2022