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ICCVAM Biennial Report 2020-2021

Biennial Progress Report 2020-2021 Interagency Coordinating Committee on the Validation of Alternative Methods

Testing to Expand the Applicability Domain of Three In Vitro Skin Sensitization Assays

In 2021, OECD issued Guideline 497, Defined Approaches on Skin Sensitisation. Drafted and sponsored by ICCVAM agency scientists and international partners, Guideline 497 is the first internationally harmonized guideline to describe a non-animal approach that can be used to replace an animal test to identify skin sensitizers.

To assess and expand the potential applicability of these defined approaches and those accepted by EPA to a broader range of chemical types, ICCVAM agencies nominated more than 200 chemicals for additional testing in the direct peptide reactivity assay, the KeratinoSens assay, and the human cell line activation test. Chemicals tested included pesticide ingredients and formulations, industrial chemicals, and personal care product ingredients. NTP completed this testing in 2020; reports are being prepared for publication in 2022. A poster describing performance of these test methods individually and in the defined approach for testing of 27 agrochemical formulations (Strickland et al.) was presented at the 11th World Congress on Alternatives and Animal Use in the Life Sciences.