Updates to OECD In Vitro and In Chemico Test Guidelines

The Organisation for Economic Co-operation and Development (OECD) has published several new or updated in vitro and in chemico test guidelines.

New test guidelines include the following:

  • Test No. 494: Vitrigel-Eye Irritancy Test Method for Identifying Chemicals Not Requiring Classification and Labelling for Eye Irritation or Serious Eye Damage
  • Test No. 495: Ros (Reactive Oxygen Species) Assay for Photoreactivity

Updated versions of existing test guidelines include the following:

  • Test No. 431: In Vitro Skin Corrosion: Reconstructed Human Epidermis (RHE) Test Method. The LabCyte EPI-MODEL24 was added.
  • Test No. 432: In Vitro 3T3 NRU Phototoxicity Test
  • Test No. 439: In Vitro Skin Irritation: Reconstructed Human Epidermis Test Method. Skin+ and epiCS “me-too” tests were added.
  • Test No. 442C: In Chemico Skin Sensitisation. The updated test guideline incorporates a new test method, the Amino acid Derivative Reactivity Assay (ADRA), which addresses the first key event of the adverse outcome pathway (AOP) for skin sensitisation: covalent binding to proteins.
  • Test No. 492: Reconstructed Human Cornea-like Epithelium (RhCE) Test Method for Identifying Chemicals Not Requiring Classification and Labelling for Eye Irritation or Serious Eye Damage. The MCTT HCE™ “me-too” method was added.

Furthermore, new and updated ecotoxicity test guidelines that refine the use of fish in regulatory toxicity testing have been published:

  • Test No. 248: Xenopus Eleutheroembryonic Thyroid Assay (XETA) (refinement method)
  • Test No. 203: Fish, Acute Toxicity Test. Guidance on the optional collection of clinical signs indicating moribundity was added, and opportunities to reduce and replace the use of fish in acute fish toxicity testing were included.