From Reduction to Replacement: Challenges and Proposed Solutions for Animal-Free Safety Assessment of Hydrocarbon UVCB Substances

Abstract

Highlights • UVCB substances derived from petroleum and renewable feedstocks are a category of complex substances spanning a continuum of hydrocarbon distributions, with well-established hazard profiles.• Read-across and predictive models developed based on historical datasets have been extensively used to reduce animal testing.• Full replacement of animal testing remains challenging because of UVCB complexity and difficult-to-test properties.• Eight key scientific, technical and regulatory challenges limiting animal-free UVCB assessment are identified and practical short-, mid- and long-term solutions are proposed to address these challenges.• A roadmap aligned with the European Commission initiative to phase out animal testing is presented using hydrocarbon UVCB as a case study. The transition to animal-free chemical safety assessment is expected to follow a different timeline for UVCB substances as compared to most industrial chemicals.