Amendment of Hazardous Materials Regulations to Consider In Vitro Methods for Classification of Corrosives

In August 2021, the Pipeline and Hazardous Materials Safety Administration (PHMSA) of the U.S. Department of Transportation published a Notice of Proposed Rulemaking (86 FR 43844) to amend certain sections of the Hazardous Materials Regulations (49 CFR parts 171 to 180). The purpose of the amendments is to maintain alignment with international regulations and standards relevant to the transportation of hazardous materials. The proposed amendments build on international collaborations of PHMSA with the United Nations to update the classification criteria for Class 8 (corrosive) substances to include in vitro non-animal test methods. The rulemaking incorporates the 2016 version of OECD Test No. 431, In Vitro Skin Corrosion: Reconstructed Human Epidermis (RHE) Test Method, used to assign a packing group to Class 8 materials. The rulemaking also provides an opportunity to assign certain Class 8 materials to a more conservative packing group in lieu of additional in vivo testing, reducing the need for animal testing to transport corrosive materials safely. The public comment period for the proposed rulemaking ended in October 2021 and the final rule is now being reviewed.