2025 AIChE Annual Meeting

(37a) Chemical Characterization of Tire Wear Particles Via Solvent Extraction

Author

Tire wear particles (TWPs), generated from the abrasion of vehicle tires on road surfaces, are a widespread source of microplastic pollution across all environmental compartments. Growing concern over TWP pollution stems from the chemical complexity of tire rubber additives, which can undergo transformations upon environmental exposure, along with observed toxicity of leachates to aquatic organisms. While certain tire-derived chemicals have been studied, the overall composition of tire rubber remains poorly characterized, hindering risk assessment efforts regarding TWPs, their leachable additives, and their transformation products.

To begin addressing this critical knowledge gap, this study extracted and characterized tire-derived compounds from "lab-generated" TWPs. Samples were prepared from 60 used tires collected from a local tire shop to capture the chemical diversity of tire formulations across numerous tire types and manufacturers. An optimized solvent mixture was used to extract additive compounds, and gas chromatography–mass spectrometry (GC/MS) analysis enabled their identification. These preliminary findings provide an expanded and generalizable view of the chemical complexity of tire rubber, establishing a foundation for future work targeting aqueous leachates and environmental samples from runoff-impacted environments.