On 30th June 2022, the OECD published the Test Guideline No. 125, which harmonises the determination of particle size distribution specifically for nanomaterials. It is an important building block for the implementation of nano-specific requirements within the framework of legislation on chemical safety, for example for the REACH Regulation.
The publication of the OECD Test Guideline No. 125 - Nanomaterial Particle Size and Size Distribution of Nanomaterials closes an important gap of the OECD's internationally agreed Test Guidelines. Until now, no harmonised OECD Test Guideline for the sizing of nanomaterials was available. With the new OECD Test Guideline, spherical and fibrous nanomaterials can be measured, identified and characterised in a standardised way.
The work on the development of the Test Guideline No. 125 was funded by the Federal Ministry for the Environment, Nature Conservation, Nuclear Safety and Consumer Protection (BMUV). The Test Guideline was developed under coordination of the Federal Institute for Occupational Safety and Health (BAuA), the Federal Institute for Materials Research and Testing (BAM) and the German Environment Agency (UBA) in international cooperation with29 other institutions from four continents.
The OECD Test Guidelines for the testing of chemicals comprise a set of standardised, internationally harmonised and accepted test methods and guidance documents used to characterise chemicals and to study their effects on humans and the environment. These Test Guidelines have been developed primarily for readily soluble organic chemicals. The behaviour of nanomaterials is different from that of readily soluble organic chemicals. Although it is recognised that the OECD Test Guidelines are generally applicable to nanomaterials, there is a need to adapt or supplement them for specific testing tasks.
OECD Test Guidelines are covered by the OECD Mutual Acceptance of Data (MAD) system. Under this system, laboratory test results related to the purpose of safety assessment of chemicals that are generated in accordance with OECD Test Guidelines and OECD Principles of Good Laboratory Practices are accepted in all OECD countries.