OECD’s Test Guideline Programme Adopts ICAPO-led Project on Nonanimal Respiratory Irritation

New Project to Develop a Test Guideline for Respiratory Irritation: Every year, the Test Guideline Programme reviews many new project proposals. If approved, the Test Guideline Programme dedicates time and resources to the development of these projects, which can vary widely in duration but typically remain on the workplan for 1-3 years. Together with the United States, ICAPO members from the PETA Science Consortium International had their project adopted onto the workplan to develop a Test Guideline on an in vitro reconstructed human respiratory epithelium (RHRE) test method for identifying respiratory tissue irritation. 

Other New Nonanimal Projects: Several other new nonanimal methods were approved and brought onto the Test Guideline Programme this year.

• The new Guidance Document (GD) on biodegradation testing of difficult-to-test substances has the potential to reduce the need for additional animal testing. 
• The revision of OECD GD 280, “Guidance Document on the Determination of in vitro intrinsic clearance using cryopreserved hepatocytes (RT-HEP) or liver S9 subcellular fractions (RT-S9) from rainbow trout and extrapolation to in vivo intrinsic clearance” could decrease fish use.  
• The revision of Test Guideline (TG) 492B, “EpiOcular time-to-toxicity test method for hazard identification and labelling of eye irritating chemicals” would provide an additional in vitro test method option. 
• A Detailed Review Paper on in vitro renal cytotoxicity assays will lay the groundwork for the creation of new in vitro TGs that could replace animal testing.   
• A new TG on a Human Mineralocorticoid Receptor Transactivation Assay: MRTA provides an important in vitro test for endocrine disruption. 

The complete 2026 Test Guideline Work Plan can be found on the Guidelines for the Testing of Chemicals page.