A Tiered Quantification and Source Mapping Framework for Tire Wear Particle Analysis in Environmental Matrices

Tire wear particles (TWPs) are a major source of microplastic emissions, accurate quantification of TWPs remains challenging due to tread composition heterogeneity and inconsistent methods. To improve the quantification accuracy under scarce tire composition data, a novel method was established based on real treads to establish more accurate quantitative curves using pyrolysis gas chromatography-mass spectrometry. For the first time, the rubber content of three types of treads was quantified using a comprehensive group of pyrolysis monomers and derivatives. The approach was validated by tread cryogrinds, which showed the accuracy was improved to 94-113% compared with previous methods. A tiered approach was established to calculate worn tread mass while distinguishing and eliminating interfering signals in matrices. Further, an analytical framework for TWPs in various environmental samples to identify their sources and quantify fluxes was proposed with the availability of auxiliary data. This framework can serve as basis for more efficient management of TWPs contamination.