The specific OECD Test Guidelines for Chemicals (including nanomaterials) form the basis for the harmonised assessment of potential hazards to humans and the environment worldwide. Reference is made to the Test Guidelines in the European Regulation on the Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH). The testing and information requirements set out in REACH have to be fulfilled using the techniques specified in the Test Guidelines.
The introduction of testing and information requirements for the registration of nanoforms of substances under REACH has made it mandatory to test substances’ morphological properties as an additional criterion for toxicity assessment. In order to ensure the comparability of the results, it is necessary to define standard methods that are suitable for the determination of these properties. In this project, which was funded by the Federal Ministry for the Environment, Conservation and Nuclear Safety (Bundesministerium für Umwelt, Naturschutz und nukleare Sicherheit, BMU) (Funding Code FKZ 3717 66 415 0), the Federal Institute for Occupational Safety and Health (Bundesanstalt für Arbeitsschutz und Arbeitsmedizin, BAuA) developed the part of a new OECD test guideline that describes the pairwise determination of the diameter and length of fibrous nanomaterials and their number size distribution. Only the pairwise determination of both quantities allows the toxicity of fibrous nanomaterials to be assessed.
A draft of the test guideline was drawn up and discussed with the client and a joint expert group made up of experts from the OECD’s Working Party on Manufactured Nanomaterials (WPMN) and Working Group of National Co-ordinators of the Test Guidelines Programme (WNT). An interlaboratory comparison was subsequently organised to validate the measurement instructions given in the test guideline. All the results were recorded in a validation report that, by and large, confirmed the methods under examination were suitable for their intended use. The test guideline was revised on the basis of this report. Both the report and the updated draft test guideline are currently being prepared for submission to the WNT meeting in April 2022.
BAuA was responsible for the overall coordination of the work that was done on behalf of the German Environment Agency (Umweltbundesamt, UBA), and committed to actively support the commenting and approval process at OECD level following the conclusion of the project. The publication of the test guideline is expected towards the end of the first half of 2022.
Unit 4.5 "Particulate Hazardous Substances, Advanced Materials"